1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2015 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20 #include "linux-low.h"
21 #include "nat/linux-osdata.h"
26 #include "nat/linux-nat.h"
27 #include "nat/linux-waitpid.h"
29 #include "nat/gdb_ptrace.h"
30 #include "nat/linux-ptrace.h"
31 #include "nat/linux-procfs.h"
32 #include "nat/linux-personality.h"
34 #include <sys/ioctl.h>
37 #include <sys/syscall.h>
41 #include <sys/types.h>
46 #include "filestuff.h"
47 #include "tracepoint.h"
50 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
51 then ELFMAG0 will have been defined. If it didn't get included by
52 gdb_proc_service.h then including it will likely introduce a duplicate
53 definition of elf_fpregset_t. */
56 #include "nat/linux-namespaces.h"
59 #define SPUFS_MAGIC 0x23c9b64e
62 #ifdef HAVE_PERSONALITY
63 # include <sys/personality.h>
64 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
65 # define ADDR_NO_RANDOMIZE 0x0040000
74 #define W_STOPCODE(sig) ((sig) << 8 | 0x7f)
77 /* This is the kernel's hard limit. Not to be confused with
83 /* Some targets did not define these ptrace constants from the start,
84 so gdbserver defines them locally here. In the future, these may
85 be removed after they are added to asm/ptrace.h. */
86 #if !(defined(PT_TEXT_ADDR) \
87 || defined(PT_DATA_ADDR) \
88 || defined(PT_TEXT_END_ADDR))
89 #if defined(__mcoldfire__)
90 /* These are still undefined in 3.10 kernels. */
91 #define PT_TEXT_ADDR 49*4
92 #define PT_DATA_ADDR 50*4
93 #define PT_TEXT_END_ADDR 51*4
94 /* BFIN already defines these since at least 2.6.32 kernels. */
96 #define PT_TEXT_ADDR 220
97 #define PT_TEXT_END_ADDR 224
98 #define PT_DATA_ADDR 228
99 /* These are still undefined in 3.10 kernels. */
100 #elif defined(__TMS320C6X__)
101 #define PT_TEXT_ADDR (0x10000*4)
102 #define PT_DATA_ADDR (0x10004*4)
103 #define PT_TEXT_END_ADDR (0x10008*4)
107 #ifdef HAVE_LINUX_BTRACE
108 # include "nat/linux-btrace.h"
109 # include "btrace-common.h"
112 #ifndef HAVE_ELF32_AUXV_T
113 /* Copied from glibc's elf.h. */
116 uint32_t a_type
; /* Entry type */
119 uint32_t a_val
; /* Integer value */
120 /* We use to have pointer elements added here. We cannot do that,
121 though, since it does not work when using 32-bit definitions
122 on 64-bit platforms and vice versa. */
127 #ifndef HAVE_ELF64_AUXV_T
128 /* Copied from glibc's elf.h. */
131 uint64_t a_type
; /* Entry type */
134 uint64_t a_val
; /* Integer value */
135 /* We use to have pointer elements added here. We cannot do that,
136 though, since it does not work when using 32-bit definitions
137 on 64-bit platforms and vice versa. */
144 /* See nat/linux-nat.h. */
147 ptid_of_lwp (struct lwp_info
*lwp
)
149 return ptid_of (get_lwp_thread (lwp
));
152 /* See nat/linux-nat.h. */
155 lwp_set_arch_private_info (struct lwp_info
*lwp
,
156 struct arch_lwp_info
*info
)
158 lwp
->arch_private
= info
;
161 /* See nat/linux-nat.h. */
163 struct arch_lwp_info
*
164 lwp_arch_private_info (struct lwp_info
*lwp
)
166 return lwp
->arch_private
;
169 /* See nat/linux-nat.h. */
172 lwp_is_stopped (struct lwp_info
*lwp
)
177 /* See nat/linux-nat.h. */
179 enum target_stop_reason
180 lwp_stop_reason (struct lwp_info
*lwp
)
182 return lwp
->stop_reason
;
185 /* A list of all unknown processes which receive stop signals. Some
186 other process will presumably claim each of these as forked
187 children momentarily. */
189 struct simple_pid_list
191 /* The process ID. */
194 /* The status as reported by waitpid. */
198 struct simple_pid_list
*next
;
200 struct simple_pid_list
*stopped_pids
;
202 /* Trivial list manipulation functions to keep track of a list of new
203 stopped processes. */
206 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
208 struct simple_pid_list
*new_pid
= xmalloc (sizeof (struct simple_pid_list
));
211 new_pid
->status
= status
;
212 new_pid
->next
= *listp
;
217 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
219 struct simple_pid_list
**p
;
221 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
222 if ((*p
)->pid
== pid
)
224 struct simple_pid_list
*next
= (*p
)->next
;
226 *statusp
= (*p
)->status
;
234 enum stopping_threads_kind
236 /* Not stopping threads presently. */
237 NOT_STOPPING_THREADS
,
239 /* Stopping threads. */
242 /* Stopping and suspending threads. */
243 STOPPING_AND_SUSPENDING_THREADS
246 /* This is set while stop_all_lwps is in effect. */
247 enum stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
249 /* FIXME make into a target method? */
250 int using_threads
= 1;
252 /* True if we're presently stabilizing threads (moving them out of
254 static int stabilizing_threads
;
256 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
257 int step
, int signal
, siginfo_t
*info
);
258 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
259 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
260 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
261 static int linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
262 int *wstat
, int options
);
263 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
264 static struct lwp_info
*add_lwp (ptid_t ptid
);
265 static int linux_stopped_by_watchpoint (void);
266 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
267 static void proceed_all_lwps (void);
268 static int finish_step_over (struct lwp_info
*lwp
);
269 static int kill_lwp (unsigned long lwpid
, int signo
);
271 /* When the event-loop is doing a step-over, this points at the thread
273 ptid_t step_over_bkpt
;
275 /* True if the low target can hardware single-step. Such targets
276 don't need a BREAKPOINT_REINSERT_ADDR callback. */
279 can_hardware_single_step (void)
281 return (the_low_target
.breakpoint_reinsert_addr
== NULL
);
284 /* True if the low target supports memory breakpoints. If so, we'll
285 have a GET_PC implementation. */
288 supports_breakpoints (void)
290 return (the_low_target
.get_pc
!= NULL
);
293 /* Returns true if this target can support fast tracepoints. This
294 does not mean that the in-process agent has been loaded in the
298 supports_fast_tracepoints (void)
300 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
303 /* True if LWP is stopped in its stepping range. */
306 lwp_in_step_range (struct lwp_info
*lwp
)
308 CORE_ADDR pc
= lwp
->stop_pc
;
310 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
313 struct pending_signals
317 struct pending_signals
*prev
;
320 /* The read/write ends of the pipe registered as waitable file in the
322 static int linux_event_pipe
[2] = { -1, -1 };
324 /* True if we're currently in async mode. */
325 #define target_is_async_p() (linux_event_pipe[0] != -1)
327 static void send_sigstop (struct lwp_info
*lwp
);
328 static void wait_for_sigstop (void);
330 /* Return non-zero if HEADER is a 64-bit ELF file. */
333 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
335 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
336 && header
->e_ident
[EI_MAG1
] == ELFMAG1
337 && header
->e_ident
[EI_MAG2
] == ELFMAG2
338 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
340 *machine
= header
->e_machine
;
341 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
348 /* Return non-zero if FILE is a 64-bit ELF file,
349 zero if the file is not a 64-bit ELF file,
350 and -1 if the file is not accessible or doesn't exist. */
353 elf_64_file_p (const char *file
, unsigned int *machine
)
358 fd
= open (file
, O_RDONLY
);
362 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
369 return elf_64_header_p (&header
, machine
);
372 /* Accepts an integer PID; Returns true if the executable PID is
373 running is a 64-bit ELF file.. */
376 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
380 sprintf (file
, "/proc/%d/exe", pid
);
381 return elf_64_file_p (file
, machine
);
385 delete_lwp (struct lwp_info
*lwp
)
387 struct thread_info
*thr
= get_lwp_thread (lwp
);
390 debug_printf ("deleting %ld\n", lwpid_of (thr
));
393 free (lwp
->arch_private
);
397 /* Add a process to the common process list, and set its private
400 static struct process_info
*
401 linux_add_process (int pid
, int attached
)
403 struct process_info
*proc
;
405 proc
= add_process (pid
, attached
);
406 proc
->priv
= xcalloc (1, sizeof (*proc
->priv
));
408 if (the_low_target
.new_process
!= NULL
)
409 proc
->priv
->arch_private
= the_low_target
.new_process ();
414 static CORE_ADDR
get_pc (struct lwp_info
*lwp
);
416 /* Handle a GNU/Linux extended wait response. If we see a clone
417 event, we need to add the new LWP to our list (and return 0 so as
418 not to report the trap to higher layers). */
421 handle_extended_wait (struct lwp_info
*event_lwp
, int wstat
)
423 int event
= linux_ptrace_get_extended_event (wstat
);
424 struct thread_info
*event_thr
= get_lwp_thread (event_lwp
);
425 struct lwp_info
*new_lwp
;
427 if ((event
== PTRACE_EVENT_FORK
) || (event
== PTRACE_EVENT_VFORK
)
428 || (event
== PTRACE_EVENT_CLONE
))
431 unsigned long new_pid
;
434 /* Get the pid of the new lwp. */
435 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_thr
), (PTRACE_TYPE_ARG3
) 0,
438 /* If we haven't already seen the new PID stop, wait for it now. */
439 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
441 /* The new child has a pending SIGSTOP. We can't affect it until it
442 hits the SIGSTOP, but we're already attached. */
444 ret
= my_waitpid (new_pid
, &status
, __WALL
);
447 perror_with_name ("waiting for new child");
448 else if (ret
!= new_pid
)
449 warning ("wait returned unexpected PID %d", ret
);
450 else if (!WIFSTOPPED (status
))
451 warning ("wait returned unexpected status 0x%x", status
);
454 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
)
456 struct process_info
*parent_proc
;
457 struct process_info
*child_proc
;
458 struct lwp_info
*child_lwp
;
459 struct thread_info
*child_thr
;
460 struct target_desc
*tdesc
;
462 ptid
= ptid_build (new_pid
, new_pid
, 0);
466 debug_printf ("HEW: Got fork event from LWP %ld, "
468 ptid_get_lwp (ptid_of (event_thr
)),
469 ptid_get_pid (ptid
));
472 /* Add the new process to the tables and clone the breakpoint
473 lists of the parent. We need to do this even if the new process
474 will be detached, since we will need the process object and the
475 breakpoints to remove any breakpoints from memory when we
476 detach, and the client side will access registers. */
477 child_proc
= linux_add_process (new_pid
, 0);
478 gdb_assert (child_proc
!= NULL
);
479 child_lwp
= add_lwp (ptid
);
480 gdb_assert (child_lwp
!= NULL
);
481 child_lwp
->stopped
= 1;
482 child_lwp
->must_set_ptrace_flags
= 1;
483 child_lwp
->status_pending_p
= 0;
484 child_thr
= get_lwp_thread (child_lwp
);
485 child_thr
->last_resume_kind
= resume_stop
;
486 child_thr
->last_status
.kind
= TARGET_WAITKIND_STOPPED
;
488 parent_proc
= get_thread_process (event_thr
);
489 child_proc
->attached
= parent_proc
->attached
;
490 clone_all_breakpoints (&child_proc
->breakpoints
,
491 &child_proc
->raw_breakpoints
,
492 parent_proc
->breakpoints
);
494 tdesc
= xmalloc (sizeof (struct target_desc
));
495 copy_target_description (tdesc
, parent_proc
->tdesc
);
496 child_proc
->tdesc
= tdesc
;
498 /* Clone arch-specific process data. */
499 if (the_low_target
.new_fork
!= NULL
)
500 the_low_target
.new_fork (parent_proc
, child_proc
);
502 /* Save fork info in the parent thread. */
503 if (event
== PTRACE_EVENT_FORK
)
504 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_FORKED
;
505 else if (event
== PTRACE_EVENT_VFORK
)
506 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORKED
;
508 event_lwp
->waitstatus
.value
.related_pid
= ptid
;
510 /* The status_pending field contains bits denoting the
511 extended event, so when the pending event is handled,
512 the handler will look at lwp->waitstatus. */
513 event_lwp
->status_pending_p
= 1;
514 event_lwp
->status_pending
= wstat
;
516 /* Report the event. */
521 debug_printf ("HEW: Got clone event "
522 "from LWP %ld, new child is LWP %ld\n",
523 lwpid_of (event_thr
), new_pid
);
525 ptid
= ptid_build (pid_of (event_thr
), new_pid
, 0);
526 new_lwp
= add_lwp (ptid
);
528 /* Either we're going to immediately resume the new thread
529 or leave it stopped. linux_resume_one_lwp is a nop if it
530 thinks the thread is currently running, so set this first
531 before calling linux_resume_one_lwp. */
532 new_lwp
->stopped
= 1;
534 /* If we're suspending all threads, leave this one suspended
536 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
)
537 new_lwp
->suspended
= 1;
539 /* Normally we will get the pending SIGSTOP. But in some cases
540 we might get another signal delivered to the group first.
541 If we do get another signal, be sure not to lose it. */
542 if (WSTOPSIG (status
) != SIGSTOP
)
544 new_lwp
->stop_expected
= 1;
545 new_lwp
->status_pending_p
= 1;
546 new_lwp
->status_pending
= status
;
549 /* Don't report the event. */
552 else if (event
== PTRACE_EVENT_VFORK_DONE
)
554 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORK_DONE
;
556 /* Report the event. */
560 internal_error (__FILE__
, __LINE__
, _("unknown ptrace event %d"), event
);
563 /* Return the PC as read from the regcache of LWP, without any
567 get_pc (struct lwp_info
*lwp
)
569 struct thread_info
*saved_thread
;
570 struct regcache
*regcache
;
573 if (the_low_target
.get_pc
== NULL
)
576 saved_thread
= current_thread
;
577 current_thread
= get_lwp_thread (lwp
);
579 regcache
= get_thread_regcache (current_thread
, 1);
580 pc
= (*the_low_target
.get_pc
) (regcache
);
583 debug_printf ("pc is 0x%lx\n", (long) pc
);
585 current_thread
= saved_thread
;
589 /* This function should only be called if LWP got a SIGTRAP.
590 The SIGTRAP could mean several things.
592 On i386, where decr_pc_after_break is non-zero:
594 If we were single-stepping this process using PTRACE_SINGLESTEP, we
595 will get only the one SIGTRAP. The value of $eip will be the next
596 instruction. If the instruction we stepped over was a breakpoint,
597 we need to decrement the PC.
599 If we continue the process using PTRACE_CONT, we will get a
600 SIGTRAP when we hit a breakpoint. The value of $eip will be
601 the instruction after the breakpoint (i.e. needs to be
602 decremented). If we report the SIGTRAP to GDB, we must also
603 report the undecremented PC. If the breakpoint is removed, we
604 must resume at the decremented PC.
606 On a non-decr_pc_after_break machine with hardware or kernel
609 If we either single-step a breakpoint instruction, or continue and
610 hit a breakpoint instruction, our PC will point at the breakpoint
614 check_stopped_by_breakpoint (struct lwp_info
*lwp
)
617 CORE_ADDR sw_breakpoint_pc
;
618 struct thread_info
*saved_thread
;
619 #if USE_SIGTRAP_SIGINFO
623 if (the_low_target
.get_pc
== NULL
)
627 sw_breakpoint_pc
= pc
- the_low_target
.decr_pc_after_break
;
629 /* breakpoint_at reads from the current thread. */
630 saved_thread
= current_thread
;
631 current_thread
= get_lwp_thread (lwp
);
633 #if USE_SIGTRAP_SIGINFO
634 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
635 (PTRACE_TYPE_ARG3
) 0, &siginfo
) == 0)
637 if (siginfo
.si_signo
== SIGTRAP
)
639 if (siginfo
.si_code
== GDB_ARCH_TRAP_BRKPT
)
643 struct thread_info
*thr
= get_lwp_thread (lwp
);
645 debug_printf ("CSBB: %s stopped by software breakpoint\n",
646 target_pid_to_str (ptid_of (thr
)));
649 /* Back up the PC if necessary. */
650 if (pc
!= sw_breakpoint_pc
)
652 struct regcache
*regcache
653 = get_thread_regcache (current_thread
, 1);
654 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
657 lwp
->stop_pc
= sw_breakpoint_pc
;
658 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
659 current_thread
= saved_thread
;
662 else if (siginfo
.si_code
== TRAP_HWBKPT
)
666 struct thread_info
*thr
= get_lwp_thread (lwp
);
668 debug_printf ("CSBB: %s stopped by hardware "
669 "breakpoint/watchpoint\n",
670 target_pid_to_str (ptid_of (thr
)));
674 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
675 current_thread
= saved_thread
;
678 else if (siginfo
.si_code
== TRAP_TRACE
)
682 struct thread_info
*thr
= get_lwp_thread (lwp
);
684 debug_printf ("CSBB: %s stopped by trace\n",
685 target_pid_to_str (ptid_of (thr
)));
691 /* We may have just stepped a breakpoint instruction. E.g., in
692 non-stop mode, GDB first tells the thread A to step a range, and
693 then the user inserts a breakpoint inside the range. In that
694 case we need to report the breakpoint PC. */
695 if ((!lwp
->stepping
|| lwp
->stop_pc
== sw_breakpoint_pc
)
696 && (*the_low_target
.breakpoint_at
) (sw_breakpoint_pc
))
700 struct thread_info
*thr
= get_lwp_thread (lwp
);
702 debug_printf ("CSBB: %s stopped by software breakpoint\n",
703 target_pid_to_str (ptid_of (thr
)));
706 /* Back up the PC if necessary. */
707 if (pc
!= sw_breakpoint_pc
)
709 struct regcache
*regcache
710 = get_thread_regcache (current_thread
, 1);
711 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
714 lwp
->stop_pc
= sw_breakpoint_pc
;
715 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
716 current_thread
= saved_thread
;
720 if (hardware_breakpoint_inserted_here (pc
))
724 struct thread_info
*thr
= get_lwp_thread (lwp
);
726 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
727 target_pid_to_str (ptid_of (thr
)));
731 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
732 current_thread
= saved_thread
;
737 current_thread
= saved_thread
;
741 static struct lwp_info
*
742 add_lwp (ptid_t ptid
)
744 struct lwp_info
*lwp
;
746 lwp
= (struct lwp_info
*) xmalloc (sizeof (*lwp
));
747 memset (lwp
, 0, sizeof (*lwp
));
749 if (the_low_target
.new_thread
!= NULL
)
750 the_low_target
.new_thread (lwp
);
752 lwp
->thread
= add_thread (ptid
, lwp
);
757 /* Start an inferior process and returns its pid.
758 ALLARGS is a vector of program-name and args. */
761 linux_create_inferior (char *program
, char **allargs
)
763 struct lwp_info
*new_lwp
;
766 struct cleanup
*restore_personality
767 = maybe_disable_address_space_randomization (disable_randomization
);
769 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
775 perror_with_name ("fork");
780 ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
782 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
783 signal (__SIGRTMIN
+ 1, SIG_DFL
);
788 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
789 stdout to stderr so that inferior i/o doesn't corrupt the connection.
790 Also, redirect stdin to /dev/null. */
791 if (remote_connection_is_stdio ())
794 open ("/dev/null", O_RDONLY
);
796 if (write (2, "stdin/stdout redirected\n",
797 sizeof ("stdin/stdout redirected\n") - 1) < 0)
799 /* Errors ignored. */;
803 execv (program
, allargs
);
805 execvp (program
, allargs
);
807 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
813 do_cleanups (restore_personality
);
815 linux_add_process (pid
, 0);
817 ptid
= ptid_build (pid
, pid
, 0);
818 new_lwp
= add_lwp (ptid
);
819 new_lwp
->must_set_ptrace_flags
= 1;
824 /* Implement the arch_setup target_ops method. */
827 linux_arch_setup (void)
829 the_low_target
.arch_setup ();
832 /* Attach to an inferior process. Returns 0 on success, ERRNO on
836 linux_attach_lwp (ptid_t ptid
)
838 struct lwp_info
*new_lwp
;
839 int lwpid
= ptid_get_lwp (ptid
);
841 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
845 new_lwp
= add_lwp (ptid
);
847 /* We need to wait for SIGSTOP before being able to make the next
848 ptrace call on this LWP. */
849 new_lwp
->must_set_ptrace_flags
= 1;
851 if (linux_proc_pid_is_stopped (lwpid
))
854 debug_printf ("Attached to a stopped process\n");
856 /* The process is definitely stopped. It is in a job control
857 stop, unless the kernel predates the TASK_STOPPED /
858 TASK_TRACED distinction, in which case it might be in a
859 ptrace stop. Make sure it is in a ptrace stop; from there we
860 can kill it, signal it, et cetera.
862 First make sure there is a pending SIGSTOP. Since we are
863 already attached, the process can not transition from stopped
864 to running without a PTRACE_CONT; so we know this signal will
865 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
866 probably already in the queue (unless this kernel is old
867 enough to use TASK_STOPPED for ptrace stops); but since
868 SIGSTOP is not an RT signal, it can only be queued once. */
869 kill_lwp (lwpid
, SIGSTOP
);
871 /* Finally, resume the stopped process. This will deliver the
872 SIGSTOP (or a higher priority signal, just like normal
873 PTRACE_ATTACH), which we'll catch later on. */
874 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
877 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
880 There are several cases to consider here:
882 1) gdbserver has already attached to the process and is being notified
883 of a new thread that is being created.
884 In this case we should ignore that SIGSTOP and resume the
885 process. This is handled below by setting stop_expected = 1,
886 and the fact that add_thread sets last_resume_kind ==
889 2) This is the first thread (the process thread), and we're attaching
890 to it via attach_inferior.
891 In this case we want the process thread to stop.
892 This is handled by having linux_attach set last_resume_kind ==
893 resume_stop after we return.
895 If the pid we are attaching to is also the tgid, we attach to and
896 stop all the existing threads. Otherwise, we attach to pid and
897 ignore any other threads in the same group as this pid.
899 3) GDB is connecting to gdbserver and is requesting an enumeration of all
901 In this case we want the thread to stop.
902 FIXME: This case is currently not properly handled.
903 We should wait for the SIGSTOP but don't. Things work apparently
904 because enough time passes between when we ptrace (ATTACH) and when
905 gdb makes the next ptrace call on the thread.
907 On the other hand, if we are currently trying to stop all threads, we
908 should treat the new thread as if we had sent it a SIGSTOP. This works
909 because we are guaranteed that the add_lwp call above added us to the
910 end of the list, and so the new thread has not yet reached
911 wait_for_sigstop (but will). */
912 new_lwp
->stop_expected
= 1;
917 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
918 already attached. Returns true if a new LWP is found, false
922 attach_proc_task_lwp_callback (ptid_t ptid
)
924 /* Is this a new thread? */
925 if (find_thread_ptid (ptid
) == NULL
)
927 int lwpid
= ptid_get_lwp (ptid
);
931 debug_printf ("Found new lwp %d\n", lwpid
);
933 err
= linux_attach_lwp (ptid
);
935 /* Be quiet if we simply raced with the thread exiting. EPERM
936 is returned if the thread's task still exists, and is marked
937 as exited or zombie, as well as other conditions, so in that
938 case, confirm the status in /proc/PID/status. */
940 || (err
== EPERM
&& linux_proc_pid_is_gone (lwpid
)))
944 debug_printf ("Cannot attach to lwp %d: "
945 "thread is gone (%d: %s)\n",
946 lwpid
, err
, strerror (err
));
951 warning (_("Cannot attach to lwp %d: %s"),
953 linux_ptrace_attach_fail_reason_string (ptid
, err
));
961 /* Attach to PID. If PID is the tgid, attach to it and all
965 linux_attach (unsigned long pid
)
967 ptid_t ptid
= ptid_build (pid
, pid
, 0);
970 /* Attach to PID. We will check for other threads
972 err
= linux_attach_lwp (ptid
);
974 error ("Cannot attach to process %ld: %s",
975 pid
, linux_ptrace_attach_fail_reason_string (ptid
, err
));
977 linux_add_process (pid
, 1);
981 struct thread_info
*thread
;
983 /* Don't ignore the initial SIGSTOP if we just attached to this
984 process. It will be collected by wait shortly. */
985 thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
986 thread
->last_resume_kind
= resume_stop
;
989 /* We must attach to every LWP. If /proc is mounted, use that to
990 find them now. On the one hand, the inferior may be using raw
991 clone instead of using pthreads. On the other hand, even if it
992 is using pthreads, GDB may not be connected yet (thread_db needs
993 to do symbol lookups, through qSymbol). Also, thread_db walks
994 structures in the inferior's address space to find the list of
995 threads/LWPs, and those structures may well be corrupted. Note
996 that once thread_db is loaded, we'll still use it to list threads
997 and associate pthread info with each LWP. */
998 linux_proc_attach_tgid_threads (pid
, attach_proc_task_lwp_callback
);
1009 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
1011 struct counter
*counter
= args
;
1013 if (ptid_get_pid (entry
->id
) == counter
->pid
)
1015 if (++counter
->count
> 1)
1023 last_thread_of_process_p (int pid
)
1025 struct counter counter
= { pid
, 0 };
1027 return (find_inferior (&all_threads
,
1028 second_thread_of_pid_p
, &counter
) == NULL
);
1034 linux_kill_one_lwp (struct lwp_info
*lwp
)
1036 struct thread_info
*thr
= get_lwp_thread (lwp
);
1037 int pid
= lwpid_of (thr
);
1039 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1040 there is no signal context, and ptrace(PTRACE_KILL) (or
1041 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1042 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1043 alternative is to kill with SIGKILL. We only need one SIGKILL
1044 per process, not one for each thread. But since we still support
1045 linuxthreads, and we also support debugging programs using raw
1046 clone without CLONE_THREAD, we send one for each thread. For
1047 years, we used PTRACE_KILL only, so we're being a bit paranoid
1048 about some old kernels where PTRACE_KILL might work better
1049 (dubious if there are any such, but that's why it's paranoia), so
1050 we try SIGKILL first, PTRACE_KILL second, and so we're fine
1054 kill_lwp (pid
, SIGKILL
);
1057 int save_errno
= errno
;
1059 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1060 target_pid_to_str (ptid_of (thr
)),
1061 save_errno
? strerror (save_errno
) : "OK");
1065 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1068 int save_errno
= errno
;
1070 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1071 target_pid_to_str (ptid_of (thr
)),
1072 save_errno
? strerror (save_errno
) : "OK");
1076 /* Kill LWP and wait for it to die. */
1079 kill_wait_lwp (struct lwp_info
*lwp
)
1081 struct thread_info
*thr
= get_lwp_thread (lwp
);
1082 int pid
= ptid_get_pid (ptid_of (thr
));
1083 int lwpid
= ptid_get_lwp (ptid_of (thr
));
1088 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid
, pid
);
1092 linux_kill_one_lwp (lwp
);
1094 /* Make sure it died. Notes:
1096 - The loop is most likely unnecessary.
1098 - We don't use linux_wait_for_event as that could delete lwps
1099 while we're iterating over them. We're not interested in
1100 any pending status at this point, only in making sure all
1101 wait status on the kernel side are collected until the
1104 - We don't use __WALL here as the __WALL emulation relies on
1105 SIGCHLD, and killing a stopped process doesn't generate
1106 one, nor an exit status.
1108 res
= my_waitpid (lwpid
, &wstat
, 0);
1109 if (res
== -1 && errno
== ECHILD
)
1110 res
= my_waitpid (lwpid
, &wstat
, __WCLONE
);
1111 } while (res
> 0 && WIFSTOPPED (wstat
));
1113 /* Even if it was stopped, the child may have already disappeared.
1114 E.g., if it was killed by SIGKILL. */
1115 if (res
< 0 && errno
!= ECHILD
)
1116 perror_with_name ("kill_wait_lwp");
1119 /* Callback for `find_inferior'. Kills an lwp of a given process,
1120 except the leader. */
1123 kill_one_lwp_callback (struct inferior_list_entry
*entry
, void *args
)
1125 struct thread_info
*thread
= (struct thread_info
*) entry
;
1126 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1127 int pid
= * (int *) args
;
1129 if (ptid_get_pid (entry
->id
) != pid
)
1132 /* We avoid killing the first thread here, because of a Linux kernel (at
1133 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1134 the children get a chance to be reaped, it will remain a zombie
1137 if (lwpid_of (thread
) == pid
)
1140 debug_printf ("lkop: is last of process %s\n",
1141 target_pid_to_str (entry
->id
));
1145 kill_wait_lwp (lwp
);
1150 linux_kill (int pid
)
1152 struct process_info
*process
;
1153 struct lwp_info
*lwp
;
1155 process
= find_process_pid (pid
);
1156 if (process
== NULL
)
1159 /* If we're killing a running inferior, make sure it is stopped
1160 first, as PTRACE_KILL will not work otherwise. */
1161 stop_all_lwps (0, NULL
);
1163 find_inferior (&all_threads
, kill_one_lwp_callback
, &pid
);
1165 /* See the comment in linux_kill_one_lwp. We did not kill the first
1166 thread in the list, so do so now. */
1167 lwp
= find_lwp_pid (pid_to_ptid (pid
));
1172 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1176 kill_wait_lwp (lwp
);
1178 the_target
->mourn (process
);
1180 /* Since we presently can only stop all lwps of all processes, we
1181 need to unstop lwps of other processes. */
1182 unstop_all_lwps (0, NULL
);
1186 /* Get pending signal of THREAD, for detaching purposes. This is the
1187 signal the thread last stopped for, which we need to deliver to the
1188 thread when detaching, otherwise, it'd be suppressed/lost. */
1191 get_detach_signal (struct thread_info
*thread
)
1193 enum gdb_signal signo
= GDB_SIGNAL_0
;
1195 struct lwp_info
*lp
= get_thread_lwp (thread
);
1197 if (lp
->status_pending_p
)
1198 status
= lp
->status_pending
;
1201 /* If the thread had been suspended by gdbserver, and it stopped
1202 cleanly, then it'll have stopped with SIGSTOP. But we don't
1203 want to deliver that SIGSTOP. */
1204 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1205 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1208 /* Otherwise, we may need to deliver the signal we
1210 status
= lp
->last_status
;
1213 if (!WIFSTOPPED (status
))
1216 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1217 target_pid_to_str (ptid_of (thread
)));
1221 /* Extended wait statuses aren't real SIGTRAPs. */
1222 if (WSTOPSIG (status
) == SIGTRAP
&& linux_is_extended_waitstatus (status
))
1225 debug_printf ("GPS: lwp %s had stopped with extended "
1226 "status: no pending signal\n",
1227 target_pid_to_str (ptid_of (thread
)));
1231 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1233 if (program_signals_p
&& !program_signals
[signo
])
1236 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1237 target_pid_to_str (ptid_of (thread
)),
1238 gdb_signal_to_string (signo
));
1241 else if (!program_signals_p
1242 /* If we have no way to know which signals GDB does not
1243 want to have passed to the program, assume
1244 SIGTRAP/SIGINT, which is GDB's default. */
1245 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1248 debug_printf ("GPS: lwp %s had signal %s, "
1249 "but we don't know if we should pass it. "
1250 "Default to not.\n",
1251 target_pid_to_str (ptid_of (thread
)),
1252 gdb_signal_to_string (signo
));
1258 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1259 target_pid_to_str (ptid_of (thread
)),
1260 gdb_signal_to_string (signo
));
1262 return WSTOPSIG (status
);
1267 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
1269 struct thread_info
*thread
= (struct thread_info
*) entry
;
1270 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1271 int pid
= * (int *) args
;
1274 if (ptid_get_pid (entry
->id
) != pid
)
1277 /* If there is a pending SIGSTOP, get rid of it. */
1278 if (lwp
->stop_expected
)
1281 debug_printf ("Sending SIGCONT to %s\n",
1282 target_pid_to_str (ptid_of (thread
)));
1284 kill_lwp (lwpid_of (thread
), SIGCONT
);
1285 lwp
->stop_expected
= 0;
1288 /* Flush any pending changes to the process's registers. */
1289 regcache_invalidate_thread (thread
);
1291 /* Pass on any pending signal for this thread. */
1292 sig
= get_detach_signal (thread
);
1294 /* Finally, let it resume. */
1295 if (the_low_target
.prepare_to_resume
!= NULL
)
1296 the_low_target
.prepare_to_resume (lwp
);
1297 if (ptrace (PTRACE_DETACH
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
1298 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1299 error (_("Can't detach %s: %s"),
1300 target_pid_to_str (ptid_of (thread
)),
1308 linux_detach (int pid
)
1310 struct process_info
*process
;
1312 process
= find_process_pid (pid
);
1313 if (process
== NULL
)
1316 /* Stop all threads before detaching. First, ptrace requires that
1317 the thread is stopped to sucessfully detach. Second, thread_db
1318 may need to uninstall thread event breakpoints from memory, which
1319 only works with a stopped process anyway. */
1320 stop_all_lwps (0, NULL
);
1322 #ifdef USE_THREAD_DB
1323 thread_db_detach (process
);
1326 /* Stabilize threads (move out of jump pads). */
1327 stabilize_threads ();
1329 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
1331 the_target
->mourn (process
);
1333 /* Since we presently can only stop all lwps of all processes, we
1334 need to unstop lwps of other processes. */
1335 unstop_all_lwps (0, NULL
);
1339 /* Remove all LWPs that belong to process PROC from the lwp list. */
1342 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
1344 struct thread_info
*thread
= (struct thread_info
*) entry
;
1345 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1346 struct process_info
*process
= proc
;
1348 if (pid_of (thread
) == pid_of (process
))
1355 linux_mourn (struct process_info
*process
)
1357 struct process_info_private
*priv
;
1359 #ifdef USE_THREAD_DB
1360 thread_db_mourn (process
);
1363 find_inferior (&all_threads
, delete_lwp_callback
, process
);
1365 /* Freeing all private data. */
1366 priv
= process
->priv
;
1367 free (priv
->arch_private
);
1369 process
->priv
= NULL
;
1371 remove_process (process
);
1375 linux_join (int pid
)
1380 ret
= my_waitpid (pid
, &status
, 0);
1381 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1383 } while (ret
!= -1 || errno
!= ECHILD
);
1386 /* Return nonzero if the given thread is still alive. */
1388 linux_thread_alive (ptid_t ptid
)
1390 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1392 /* We assume we always know if a thread exits. If a whole process
1393 exited but we still haven't been able to report it to GDB, we'll
1394 hold on to the last lwp of the dead process. */
1401 /* Return 1 if this lwp still has an interesting status pending. If
1402 not (e.g., it had stopped for a breakpoint that is gone), return
1406 thread_still_has_status_pending_p (struct thread_info
*thread
)
1408 struct lwp_info
*lp
= get_thread_lwp (thread
);
1410 if (!lp
->status_pending_p
)
1413 /* If we got a `vCont;t', but we haven't reported a stop yet, do
1414 report any status pending the LWP may have. */
1415 if (thread
->last_resume_kind
== resume_stop
1416 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
1419 if (thread
->last_resume_kind
!= resume_stop
1420 && (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1421 || lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1423 struct thread_info
*saved_thread
;
1427 gdb_assert (lp
->last_status
!= 0);
1431 saved_thread
= current_thread
;
1432 current_thread
= thread
;
1434 if (pc
!= lp
->stop_pc
)
1437 debug_printf ("PC of %ld changed\n",
1442 #if !USE_SIGTRAP_SIGINFO
1443 else if (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1444 && !(*the_low_target
.breakpoint_at
) (pc
))
1447 debug_printf ("previous SW breakpoint of %ld gone\n",
1451 else if (lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
1452 && !hardware_breakpoint_inserted_here (pc
))
1455 debug_printf ("previous HW breakpoint of %ld gone\n",
1461 current_thread
= saved_thread
;
1466 debug_printf ("discarding pending breakpoint status\n");
1467 lp
->status_pending_p
= 0;
1475 /* Return 1 if this lwp has an interesting status pending. */
1477 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1479 struct thread_info
*thread
= (struct thread_info
*) entry
;
1480 struct lwp_info
*lp
= get_thread_lwp (thread
);
1481 ptid_t ptid
= * (ptid_t
*) arg
;
1483 /* Check if we're only interested in events from a specific process
1484 or a specific LWP. */
1485 if (!ptid_match (ptid_of (thread
), ptid
))
1488 if (lp
->status_pending_p
1489 && !thread_still_has_status_pending_p (thread
))
1491 linux_resume_one_lwp (lp
, lp
->stepping
, GDB_SIGNAL_0
, NULL
);
1495 return lp
->status_pending_p
;
1499 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1501 ptid_t ptid
= *(ptid_t
*) data
;
1504 if (ptid_get_lwp (ptid
) != 0)
1505 lwp
= ptid_get_lwp (ptid
);
1507 lwp
= ptid_get_pid (ptid
);
1509 if (ptid_get_lwp (entry
->id
) == lwp
)
1516 find_lwp_pid (ptid_t ptid
)
1518 struct inferior_list_entry
*thread
1519 = find_inferior (&all_threads
, same_lwp
, &ptid
);
1524 return get_thread_lwp ((struct thread_info
*) thread
);
1527 /* Return the number of known LWPs in the tgid given by PID. */
1532 struct inferior_list_entry
*inf
, *tmp
;
1535 ALL_INFERIORS (&all_threads
, inf
, tmp
)
1537 if (ptid_get_pid (inf
->id
) == pid
)
1544 /* The arguments passed to iterate_over_lwps. */
1546 struct iterate_over_lwps_args
1548 /* The FILTER argument passed to iterate_over_lwps. */
1551 /* The CALLBACK argument passed to iterate_over_lwps. */
1552 iterate_over_lwps_ftype
*callback
;
1554 /* The DATA argument passed to iterate_over_lwps. */
1558 /* Callback for find_inferior used by iterate_over_lwps to filter
1559 calls to the callback supplied to that function. Returning a
1560 nonzero value causes find_inferiors to stop iterating and return
1561 the current inferior_list_entry. Returning zero indicates that
1562 find_inferiors should continue iterating. */
1565 iterate_over_lwps_filter (struct inferior_list_entry
*entry
, void *args_p
)
1567 struct iterate_over_lwps_args
*args
1568 = (struct iterate_over_lwps_args
*) args_p
;
1570 if (ptid_match (entry
->id
, args
->filter
))
1572 struct thread_info
*thr
= (struct thread_info
*) entry
;
1573 struct lwp_info
*lwp
= get_thread_lwp (thr
);
1575 return (*args
->callback
) (lwp
, args
->data
);
1581 /* See nat/linux-nat.h. */
1584 iterate_over_lwps (ptid_t filter
,
1585 iterate_over_lwps_ftype callback
,
1588 struct iterate_over_lwps_args args
= {filter
, callback
, data
};
1589 struct inferior_list_entry
*entry
;
1591 entry
= find_inferior (&all_threads
, iterate_over_lwps_filter
, &args
);
1595 return get_thread_lwp ((struct thread_info
*) entry
);
1598 /* Detect zombie thread group leaders, and "exit" them. We can't reap
1599 their exits until all other threads in the group have exited. */
1602 check_zombie_leaders (void)
1604 struct process_info
*proc
, *tmp
;
1606 ALL_PROCESSES (proc
, tmp
)
1608 pid_t leader_pid
= pid_of (proc
);
1609 struct lwp_info
*leader_lp
;
1611 leader_lp
= find_lwp_pid (pid_to_ptid (leader_pid
));
1614 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1615 "num_lwps=%d, zombie=%d\n",
1616 leader_pid
, leader_lp
!= NULL
, num_lwps (leader_pid
),
1617 linux_proc_pid_is_zombie (leader_pid
));
1619 if (leader_lp
!= NULL
1620 /* Check if there are other threads in the group, as we may
1621 have raced with the inferior simply exiting. */
1622 && !last_thread_of_process_p (leader_pid
)
1623 && linux_proc_pid_is_zombie (leader_pid
))
1625 /* A leader zombie can mean one of two things:
1627 - It exited, and there's an exit status pending
1628 available, or only the leader exited (not the whole
1629 program). In the latter case, we can't waitpid the
1630 leader's exit status until all other threads are gone.
1632 - There are 3 or more threads in the group, and a thread
1633 other than the leader exec'd. On an exec, the Linux
1634 kernel destroys all other threads (except the execing
1635 one) in the thread group, and resets the execing thread's
1636 tid to the tgid. No exit notification is sent for the
1637 execing thread -- from the ptracer's perspective, it
1638 appears as though the execing thread just vanishes.
1639 Until we reap all other threads except the leader and the
1640 execing thread, the leader will be zombie, and the
1641 execing thread will be in `D (disc sleep)'. As soon as
1642 all other threads are reaped, the execing thread changes
1643 it's tid to the tgid, and the previous (zombie) leader
1644 vanishes, giving place to the "new" leader. We could try
1645 distinguishing the exit and exec cases, by waiting once
1646 more, and seeing if something comes out, but it doesn't
1647 sound useful. The previous leader _does_ go away, and
1648 we'll re-add the new one once we see the exec event
1649 (which is just the same as what would happen if the
1650 previous leader did exit voluntarily before some other
1655 "CZL: Thread group leader %d zombie "
1656 "(it exited, or another thread execd).\n",
1659 delete_lwp (leader_lp
);
1664 /* Callback for `find_inferior'. Returns the first LWP that is not
1665 stopped. ARG is a PTID filter. */
1668 not_stopped_callback (struct inferior_list_entry
*entry
, void *arg
)
1670 struct thread_info
*thr
= (struct thread_info
*) entry
;
1671 struct lwp_info
*lwp
;
1672 ptid_t filter
= *(ptid_t
*) arg
;
1674 if (!ptid_match (ptid_of (thr
), filter
))
1677 lwp
= get_thread_lwp (thr
);
1684 /* This function should only be called if the LWP got a SIGTRAP.
1686 Handle any tracepoint steps or hits. Return true if a tracepoint
1687 event was handled, 0 otherwise. */
1690 handle_tracepoints (struct lwp_info
*lwp
)
1692 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1693 int tpoint_related_event
= 0;
1695 gdb_assert (lwp
->suspended
== 0);
1697 /* If this tracepoint hit causes a tracing stop, we'll immediately
1698 uninsert tracepoints. To do this, we temporarily pause all
1699 threads, unpatch away, and then unpause threads. We need to make
1700 sure the unpausing doesn't resume LWP too. */
1703 /* And we need to be sure that any all-threads-stopping doesn't try
1704 to move threads out of the jump pads, as it could deadlock the
1705 inferior (LWP could be in the jump pad, maybe even holding the
1708 /* Do any necessary step collect actions. */
1709 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1711 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1713 /* See if we just hit a tracepoint and do its main collect
1715 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1719 gdb_assert (lwp
->suspended
== 0);
1720 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1722 if (tpoint_related_event
)
1725 debug_printf ("got a tracepoint event\n");
1732 /* Convenience wrapper. Returns true if LWP is presently collecting a
1736 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1737 struct fast_tpoint_collect_status
*status
)
1739 CORE_ADDR thread_area
;
1740 struct thread_info
*thread
= get_lwp_thread (lwp
);
1742 if (the_low_target
.get_thread_area
== NULL
)
1745 /* Get the thread area address. This is used to recognize which
1746 thread is which when tracing with the in-process agent library.
1747 We don't read anything from the address, and treat it as opaque;
1748 it's the address itself that we assume is unique per-thread. */
1749 if ((*the_low_target
.get_thread_area
) (lwpid_of (thread
), &thread_area
) == -1)
1752 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1755 /* The reason we resume in the caller, is because we want to be able
1756 to pass lwp->status_pending as WSTAT, and we need to clear
1757 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1758 refuses to resume. */
1761 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
1763 struct thread_info
*saved_thread
;
1765 saved_thread
= current_thread
;
1766 current_thread
= get_lwp_thread (lwp
);
1769 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1770 && supports_fast_tracepoints ()
1771 && agent_loaded_p ())
1773 struct fast_tpoint_collect_status status
;
1777 debug_printf ("Checking whether LWP %ld needs to move out of the "
1779 lwpid_of (current_thread
));
1781 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
1784 || (WSTOPSIG (*wstat
) != SIGILL
1785 && WSTOPSIG (*wstat
) != SIGFPE
1786 && WSTOPSIG (*wstat
) != SIGSEGV
1787 && WSTOPSIG (*wstat
) != SIGBUS
))
1789 lwp
->collecting_fast_tracepoint
= r
;
1793 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
1795 /* Haven't executed the original instruction yet.
1796 Set breakpoint there, and wait till it's hit,
1797 then single-step until exiting the jump pad. */
1798 lwp
->exit_jump_pad_bkpt
1799 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
1803 debug_printf ("Checking whether LWP %ld needs to move out of "
1804 "the jump pad...it does\n",
1805 lwpid_of (current_thread
));
1806 current_thread
= saved_thread
;
1813 /* If we get a synchronous signal while collecting, *and*
1814 while executing the (relocated) original instruction,
1815 reset the PC to point at the tpoint address, before
1816 reporting to GDB. Otherwise, it's an IPA lib bug: just
1817 report the signal to GDB, and pray for the best. */
1819 lwp
->collecting_fast_tracepoint
= 0;
1822 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
1823 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
1826 struct regcache
*regcache
;
1828 /* The si_addr on a few signals references the address
1829 of the faulting instruction. Adjust that as
1831 if ((WSTOPSIG (*wstat
) == SIGILL
1832 || WSTOPSIG (*wstat
) == SIGFPE
1833 || WSTOPSIG (*wstat
) == SIGBUS
1834 || WSTOPSIG (*wstat
) == SIGSEGV
)
1835 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
1836 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
1837 /* Final check just to make sure we don't clobber
1838 the siginfo of non-kernel-sent signals. */
1839 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
1841 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
1842 ptrace (PTRACE_SETSIGINFO
, lwpid_of (current_thread
),
1843 (PTRACE_TYPE_ARG3
) 0, &info
);
1846 regcache
= get_thread_regcache (current_thread
, 1);
1847 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
1848 lwp
->stop_pc
= status
.tpoint_addr
;
1850 /* Cancel any fast tracepoint lock this thread was
1852 force_unlock_trace_buffer ();
1855 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
1858 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
1859 "stopping all threads momentarily.\n");
1861 stop_all_lwps (1, lwp
);
1863 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
1864 lwp
->exit_jump_pad_bkpt
= NULL
;
1866 unstop_all_lwps (1, lwp
);
1868 gdb_assert (lwp
->suspended
>= 0);
1874 debug_printf ("Checking whether LWP %ld needs to move out of the "
1876 lwpid_of (current_thread
));
1878 current_thread
= saved_thread
;
1882 /* Enqueue one signal in the "signals to report later when out of the
1886 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1888 struct pending_signals
*p_sig
;
1889 struct thread_info
*thread
= get_lwp_thread (lwp
);
1892 debug_printf ("Deferring signal %d for LWP %ld.\n",
1893 WSTOPSIG (*wstat
), lwpid_of (thread
));
1897 struct pending_signals
*sig
;
1899 for (sig
= lwp
->pending_signals_to_report
;
1902 debug_printf (" Already queued %d\n",
1905 debug_printf (" (no more currently queued signals)\n");
1908 /* Don't enqueue non-RT signals if they are already in the deferred
1909 queue. (SIGSTOP being the easiest signal to see ending up here
1911 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
1913 struct pending_signals
*sig
;
1915 for (sig
= lwp
->pending_signals_to_report
;
1919 if (sig
->signal
== WSTOPSIG (*wstat
))
1922 debug_printf ("Not requeuing already queued non-RT signal %d"
1931 p_sig
= xmalloc (sizeof (*p_sig
));
1932 p_sig
->prev
= lwp
->pending_signals_to_report
;
1933 p_sig
->signal
= WSTOPSIG (*wstat
);
1934 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1935 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
1938 lwp
->pending_signals_to_report
= p_sig
;
1941 /* Dequeue one signal from the "signals to report later when out of
1942 the jump pad" list. */
1945 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1947 struct thread_info
*thread
= get_lwp_thread (lwp
);
1949 if (lwp
->pending_signals_to_report
!= NULL
)
1951 struct pending_signals
**p_sig
;
1953 p_sig
= &lwp
->pending_signals_to_report
;
1954 while ((*p_sig
)->prev
!= NULL
)
1955 p_sig
= &(*p_sig
)->prev
;
1957 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
1958 if ((*p_sig
)->info
.si_signo
!= 0)
1959 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
1965 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
1966 WSTOPSIG (*wstat
), lwpid_of (thread
));
1970 struct pending_signals
*sig
;
1972 for (sig
= lwp
->pending_signals_to_report
;
1975 debug_printf (" Still queued %d\n",
1978 debug_printf (" (no more queued signals)\n");
1987 /* Fetch the possibly triggered data watchpoint info and store it in
1990 On some archs, like x86, that use debug registers to set
1991 watchpoints, it's possible that the way to know which watched
1992 address trapped, is to check the register that is used to select
1993 which address to watch. Problem is, between setting the watchpoint
1994 and reading back which data address trapped, the user may change
1995 the set of watchpoints, and, as a consequence, GDB changes the
1996 debug registers in the inferior. To avoid reading back a stale
1997 stopped-data-address when that happens, we cache in LP the fact
1998 that a watchpoint trapped, and the corresponding data address, as
1999 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
2000 registers meanwhile, we have the cached data we can rely on. */
2003 check_stopped_by_watchpoint (struct lwp_info
*child
)
2005 if (the_low_target
.stopped_by_watchpoint
!= NULL
)
2007 struct thread_info
*saved_thread
;
2009 saved_thread
= current_thread
;
2010 current_thread
= get_lwp_thread (child
);
2012 if (the_low_target
.stopped_by_watchpoint ())
2014 child
->stop_reason
= TARGET_STOPPED_BY_WATCHPOINT
;
2016 if (the_low_target
.stopped_data_address
!= NULL
)
2017 child
->stopped_data_address
2018 = the_low_target
.stopped_data_address ();
2020 child
->stopped_data_address
= 0;
2023 current_thread
= saved_thread
;
2026 return child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
2029 /* Return the ptrace options that we want to try to enable. */
2032 linux_low_ptrace_options (int attached
)
2037 options
|= PTRACE_O_EXITKILL
;
2039 if (report_fork_events
)
2040 options
|= PTRACE_O_TRACEFORK
;
2042 if (report_vfork_events
)
2043 options
|= (PTRACE_O_TRACEVFORK
| PTRACE_O_TRACEVFORKDONE
);
2048 /* Do low-level handling of the event, and check if we should go on
2049 and pass it to caller code. Return the affected lwp if we are, or
2052 static struct lwp_info
*
2053 linux_low_filter_event (int lwpid
, int wstat
)
2055 struct lwp_info
*child
;
2056 struct thread_info
*thread
;
2057 int have_stop_pc
= 0;
2059 child
= find_lwp_pid (pid_to_ptid (lwpid
));
2061 /* If we didn't find a process, one of two things presumably happened:
2062 - A process we started and then detached from has exited. Ignore it.
2063 - A process we are controlling has forked and the new child's stop
2064 was reported to us by the kernel. Save its PID. */
2065 if (child
== NULL
&& WIFSTOPPED (wstat
))
2067 add_to_pid_list (&stopped_pids
, lwpid
, wstat
);
2070 else if (child
== NULL
)
2073 thread
= get_lwp_thread (child
);
2077 child
->last_status
= wstat
;
2079 /* Check if the thread has exited. */
2080 if ((WIFEXITED (wstat
) || WIFSIGNALED (wstat
)))
2083 debug_printf ("LLFE: %d exited.\n", lwpid
);
2084 if (num_lwps (pid_of (thread
)) > 1)
2087 /* If there is at least one more LWP, then the exit signal was
2088 not the end of the debugged application and should be
2095 /* This was the last lwp in the process. Since events are
2096 serialized to GDB core, and we can't report this one
2097 right now, but GDB core and the other target layers will
2098 want to be notified about the exit code/signal, leave the
2099 status pending for the next time we're able to report
2101 mark_lwp_dead (child
, wstat
);
2106 gdb_assert (WIFSTOPPED (wstat
));
2108 if (WIFSTOPPED (wstat
))
2110 struct process_info
*proc
;
2112 /* Architecture-specific setup after inferior is running. */
2113 proc
= find_process_pid (pid_of (thread
));
2114 if (proc
->tdesc
== NULL
)
2118 struct thread_info
*saved_thread
;
2120 /* This needs to happen after we have attached to the
2121 inferior and it is stopped for the first time, but
2122 before we access any inferior registers. */
2123 saved_thread
= current_thread
;
2124 current_thread
= thread
;
2126 the_low_target
.arch_setup ();
2128 current_thread
= saved_thread
;
2132 /* The process is started, but GDBserver will do
2133 architecture-specific setup after the program stops at
2134 the first instruction. */
2135 child
->status_pending_p
= 1;
2136 child
->status_pending
= wstat
;
2142 if (WIFSTOPPED (wstat
) && child
->must_set_ptrace_flags
)
2144 struct process_info
*proc
= find_process_pid (pid_of (thread
));
2145 int options
= linux_low_ptrace_options (proc
->attached
);
2147 linux_enable_event_reporting (lwpid
, options
);
2148 child
->must_set_ptrace_flags
= 0;
2151 /* Be careful to not overwrite stop_pc until
2152 check_stopped_by_breakpoint is called. */
2153 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2154 && linux_is_extended_waitstatus (wstat
))
2156 child
->stop_pc
= get_pc (child
);
2157 if (handle_extended_wait (child
, wstat
))
2159 /* The event has been handled, so just return without
2165 /* Check first whether this was a SW/HW breakpoint before checking
2166 watchpoints, because at least s390 can't tell the data address of
2167 hardware watchpoint hits, and returns stopped-by-watchpoint as
2168 long as there's a watchpoint set. */
2169 if (WIFSTOPPED (wstat
) && linux_wstatus_maybe_breakpoint (wstat
))
2171 if (check_stopped_by_breakpoint (child
))
2175 /* Note that TRAP_HWBKPT can indicate either a hardware breakpoint
2176 or hardware watchpoint. Check which is which if we got
2177 TARGET_STOPPED_BY_HW_BREAKPOINT. */
2178 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2179 && (child
->stop_reason
== TARGET_STOPPED_BY_NO_REASON
2180 || child
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
2181 check_stopped_by_watchpoint (child
);
2184 child
->stop_pc
= get_pc (child
);
2186 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGSTOP
2187 && child
->stop_expected
)
2190 debug_printf ("Expected stop.\n");
2191 child
->stop_expected
= 0;
2193 if (thread
->last_resume_kind
== resume_stop
)
2195 /* We want to report the stop to the core. Treat the
2196 SIGSTOP as a normal event. */
2198 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2199 target_pid_to_str (ptid_of (thread
)));
2201 else if (stopping_threads
!= NOT_STOPPING_THREADS
)
2203 /* Stopping threads. We don't want this SIGSTOP to end up
2206 debug_printf ("LLW: SIGSTOP caught for %s "
2207 "while stopping threads.\n",
2208 target_pid_to_str (ptid_of (thread
)));
2213 /* This is a delayed SIGSTOP. Filter out the event. */
2215 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2216 child
->stepping
? "step" : "continue",
2217 target_pid_to_str (ptid_of (thread
)));
2219 linux_resume_one_lwp (child
, child
->stepping
, 0, NULL
);
2224 child
->status_pending_p
= 1;
2225 child
->status_pending
= wstat
;
2229 /* Resume LWPs that are currently stopped without any pending status
2230 to report, but are resumed from the core's perspective. */
2233 resume_stopped_resumed_lwps (struct inferior_list_entry
*entry
)
2235 struct thread_info
*thread
= (struct thread_info
*) entry
;
2236 struct lwp_info
*lp
= get_thread_lwp (thread
);
2239 && !lp
->status_pending_p
2240 && thread
->last_resume_kind
!= resume_stop
2241 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
2243 int step
= thread
->last_resume_kind
== resume_step
;
2246 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2247 target_pid_to_str (ptid_of (thread
)),
2248 paddress (lp
->stop_pc
),
2251 linux_resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2255 /* Wait for an event from child(ren) WAIT_PTID, and return any that
2256 match FILTER_PTID (leaving others pending). The PTIDs can be:
2257 minus_one_ptid, to specify any child; a pid PTID, specifying all
2258 lwps of a thread group; or a PTID representing a single lwp. Store
2259 the stop status through the status pointer WSTAT. OPTIONS is
2260 passed to the waitpid call. Return 0 if no event was found and
2261 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2262 was found. Return the PID of the stopped child otherwise. */
2265 linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
2266 int *wstatp
, int options
)
2268 struct thread_info
*event_thread
;
2269 struct lwp_info
*event_child
, *requested_child
;
2270 sigset_t block_mask
, prev_mask
;
2273 /* N.B. event_thread points to the thread_info struct that contains
2274 event_child. Keep them in sync. */
2275 event_thread
= NULL
;
2277 requested_child
= NULL
;
2279 /* Check for a lwp with a pending status. */
2281 if (ptid_equal (filter_ptid
, minus_one_ptid
) || ptid_is_pid (filter_ptid
))
2283 event_thread
= (struct thread_info
*)
2284 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2285 if (event_thread
!= NULL
)
2286 event_child
= get_thread_lwp (event_thread
);
2287 if (debug_threads
&& event_thread
)
2288 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread
));
2290 else if (!ptid_equal (filter_ptid
, null_ptid
))
2292 requested_child
= find_lwp_pid (filter_ptid
);
2294 if (stopping_threads
== NOT_STOPPING_THREADS
2295 && requested_child
->status_pending_p
2296 && requested_child
->collecting_fast_tracepoint
)
2298 enqueue_one_deferred_signal (requested_child
,
2299 &requested_child
->status_pending
);
2300 requested_child
->status_pending_p
= 0;
2301 requested_child
->status_pending
= 0;
2302 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
2305 if (requested_child
->suspended
2306 && requested_child
->status_pending_p
)
2308 internal_error (__FILE__
, __LINE__
,
2309 "requesting an event out of a"
2310 " suspended child?");
2313 if (requested_child
->status_pending_p
)
2315 event_child
= requested_child
;
2316 event_thread
= get_lwp_thread (event_child
);
2320 if (event_child
!= NULL
)
2323 debug_printf ("Got an event from pending child %ld (%04x)\n",
2324 lwpid_of (event_thread
), event_child
->status_pending
);
2325 *wstatp
= event_child
->status_pending
;
2326 event_child
->status_pending_p
= 0;
2327 event_child
->status_pending
= 0;
2328 current_thread
= event_thread
;
2329 return lwpid_of (event_thread
);
2332 /* But if we don't find a pending event, we'll have to wait.
2334 We only enter this loop if no process has a pending wait status.
2335 Thus any action taken in response to a wait status inside this
2336 loop is responding as soon as we detect the status, not after any
2339 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2340 all signals while here. */
2341 sigfillset (&block_mask
);
2342 sigprocmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2344 /* Always pull all events out of the kernel. We'll randomly select
2345 an event LWP out of all that have events, to prevent
2347 while (event_child
== NULL
)
2351 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2354 - If the thread group leader exits while other threads in the
2355 thread group still exist, waitpid(TGID, ...) hangs. That
2356 waitpid won't return an exit status until the other threads
2357 in the group are reaped.
2359 - When a non-leader thread execs, that thread just vanishes
2360 without reporting an exit (so we'd hang if we waited for it
2361 explicitly in that case). The exec event is reported to
2362 the TGID pid (although we don't currently enable exec
2365 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2368 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2369 ret
, errno
? strerror (errno
) : "ERRNO-OK");
2375 debug_printf ("LLW: waitpid %ld received %s\n",
2376 (long) ret
, status_to_str (*wstatp
));
2379 /* Filter all events. IOW, leave all events pending. We'll
2380 randomly select an event LWP out of all that have events
2382 linux_low_filter_event (ret
, *wstatp
);
2383 /* Retry until nothing comes out of waitpid. A single
2384 SIGCHLD can indicate more than one child stopped. */
2388 /* Now that we've pulled all events out of the kernel, resume
2389 LWPs that don't have an interesting event to report. */
2390 if (stopping_threads
== NOT_STOPPING_THREADS
)
2391 for_each_inferior (&all_threads
, resume_stopped_resumed_lwps
);
2393 /* ... and find an LWP with a status to report to the core, if
2395 event_thread
= (struct thread_info
*)
2396 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2397 if (event_thread
!= NULL
)
2399 event_child
= get_thread_lwp (event_thread
);
2400 *wstatp
= event_child
->status_pending
;
2401 event_child
->status_pending_p
= 0;
2402 event_child
->status_pending
= 0;
2406 /* Check for zombie thread group leaders. Those can't be reaped
2407 until all other threads in the thread group are. */
2408 check_zombie_leaders ();
2410 /* If there are no resumed children left in the set of LWPs we
2411 want to wait for, bail. We can't just block in
2412 waitpid/sigsuspend, because lwps might have been left stopped
2413 in trace-stop state, and we'd be stuck forever waiting for
2414 their status to change (which would only happen if we resumed
2415 them). Even if WNOHANG is set, this return code is preferred
2416 over 0 (below), as it is more detailed. */
2417 if ((find_inferior (&all_threads
,
2418 not_stopped_callback
,
2419 &wait_ptid
) == NULL
))
2422 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2423 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2427 /* No interesting event to report to the caller. */
2428 if ((options
& WNOHANG
))
2431 debug_printf ("WNOHANG set, no event found\n");
2433 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2437 /* Block until we get an event reported with SIGCHLD. */
2439 debug_printf ("sigsuspend'ing\n");
2441 sigsuspend (&prev_mask
);
2442 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2446 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2448 current_thread
= event_thread
;
2450 /* Check for thread exit. */
2451 if (! WIFSTOPPED (*wstatp
))
2453 gdb_assert (last_thread_of_process_p (pid_of (event_thread
)));
2456 debug_printf ("LWP %d is the last lwp of process. "
2457 "Process %ld exiting.\n",
2458 pid_of (event_thread
), lwpid_of (event_thread
));
2459 return lwpid_of (event_thread
);
2462 return lwpid_of (event_thread
);
2465 /* Wait for an event from child(ren) PTID. PTIDs can be:
2466 minus_one_ptid, to specify any child; a pid PTID, specifying all
2467 lwps of a thread group; or a PTID representing a single lwp. Store
2468 the stop status through the status pointer WSTAT. OPTIONS is
2469 passed to the waitpid call. Return 0 if no event was found and
2470 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2471 was found. Return the PID of the stopped child otherwise. */
2474 linux_wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2476 return linux_wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2479 /* Count the LWP's that have had events. */
2482 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
2484 struct thread_info
*thread
= (struct thread_info
*) entry
;
2485 struct lwp_info
*lp
= get_thread_lwp (thread
);
2488 gdb_assert (count
!= NULL
);
2490 /* Count only resumed LWPs that have an event pending. */
2491 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2492 && lp
->status_pending_p
)
2498 /* Select the LWP (if any) that is currently being single-stepped. */
2501 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2503 struct thread_info
*thread
= (struct thread_info
*) entry
;
2504 struct lwp_info
*lp
= get_thread_lwp (thread
);
2506 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2507 && thread
->last_resume_kind
== resume_step
2508 && lp
->status_pending_p
)
2514 /* Select the Nth LWP that has had an event. */
2517 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2519 struct thread_info
*thread
= (struct thread_info
*) entry
;
2520 struct lwp_info
*lp
= get_thread_lwp (thread
);
2521 int *selector
= data
;
2523 gdb_assert (selector
!= NULL
);
2525 /* Select only resumed LWPs that have an event pending. */
2526 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2527 && lp
->status_pending_p
)
2528 if ((*selector
)-- == 0)
2534 /* Select one LWP out of those that have events pending. */
2537 select_event_lwp (struct lwp_info
**orig_lp
)
2540 int random_selector
;
2541 struct thread_info
*event_thread
= NULL
;
2543 /* In all-stop, give preference to the LWP that is being
2544 single-stepped. There will be at most one, and it's the LWP that
2545 the core is most interested in. If we didn't do this, then we'd
2546 have to handle pending step SIGTRAPs somehow in case the core
2547 later continues the previously-stepped thread, otherwise we'd
2548 report the pending SIGTRAP, and the core, not having stepped the
2549 thread, wouldn't understand what the trap was for, and therefore
2550 would report it to the user as a random signal. */
2554 = (struct thread_info
*) find_inferior (&all_threads
,
2555 select_singlestep_lwp_callback
,
2557 if (event_thread
!= NULL
)
2560 debug_printf ("SEL: Select single-step %s\n",
2561 target_pid_to_str (ptid_of (event_thread
)));
2564 if (event_thread
== NULL
)
2566 /* No single-stepping LWP. Select one at random, out of those
2567 which have had events. */
2569 /* First see how many events we have. */
2570 find_inferior (&all_threads
, count_events_callback
, &num_events
);
2571 gdb_assert (num_events
> 0);
2573 /* Now randomly pick a LWP out of those that have had
2575 random_selector
= (int)
2576 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2578 if (debug_threads
&& num_events
> 1)
2579 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2580 num_events
, random_selector
);
2583 = (struct thread_info
*) find_inferior (&all_threads
,
2584 select_event_lwp_callback
,
2588 if (event_thread
!= NULL
)
2590 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2592 /* Switch the event LWP. */
2593 *orig_lp
= event_lp
;
2597 /* Decrement the suspend count of an LWP. */
2600 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2602 struct thread_info
*thread
= (struct thread_info
*) entry
;
2603 struct lwp_info
*lwp
= get_thread_lwp (thread
);
2605 /* Ignore EXCEPT. */
2611 gdb_assert (lwp
->suspended
>= 0);
2615 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2619 unsuspend_all_lwps (struct lwp_info
*except
)
2621 find_inferior (&all_threads
, unsuspend_one_lwp
, except
);
2624 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2625 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2627 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2628 static ptid_t
linux_wait_1 (ptid_t ptid
,
2629 struct target_waitstatus
*ourstatus
,
2630 int target_options
);
2632 /* Stabilize threads (move out of jump pads).
2634 If a thread is midway collecting a fast tracepoint, we need to
2635 finish the collection and move it out of the jump pad before
2636 reporting the signal.
2638 This avoids recursion while collecting (when a signal arrives
2639 midway, and the signal handler itself collects), which would trash
2640 the trace buffer. In case the user set a breakpoint in a signal
2641 handler, this avoids the backtrace showing the jump pad, etc..
2642 Most importantly, there are certain things we can't do safely if
2643 threads are stopped in a jump pad (or in its callee's). For
2646 - starting a new trace run. A thread still collecting the
2647 previous run, could trash the trace buffer when resumed. The trace
2648 buffer control structures would have been reset but the thread had
2649 no way to tell. The thread could even midway memcpy'ing to the
2650 buffer, which would mean that when resumed, it would clobber the
2651 trace buffer that had been set for a new run.
2653 - we can't rewrite/reuse the jump pads for new tracepoints
2654 safely. Say you do tstart while a thread is stopped midway while
2655 collecting. When the thread is later resumed, it finishes the
2656 collection, and returns to the jump pad, to execute the original
2657 instruction that was under the tracepoint jump at the time the
2658 older run had been started. If the jump pad had been rewritten
2659 since for something else in the new run, the thread would now
2660 execute the wrong / random instructions. */
2663 linux_stabilize_threads (void)
2665 struct thread_info
*saved_thread
;
2666 struct thread_info
*thread_stuck
;
2669 = (struct thread_info
*) find_inferior (&all_threads
,
2670 stuck_in_jump_pad_callback
,
2672 if (thread_stuck
!= NULL
)
2675 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2676 lwpid_of (thread_stuck
));
2680 saved_thread
= current_thread
;
2682 stabilizing_threads
= 1;
2685 for_each_inferior (&all_threads
, move_out_of_jump_pad_callback
);
2687 /* Loop until all are stopped out of the jump pads. */
2688 while (find_inferior (&all_threads
, lwp_running
, NULL
) != NULL
)
2690 struct target_waitstatus ourstatus
;
2691 struct lwp_info
*lwp
;
2694 /* Note that we go through the full wait even loop. While
2695 moving threads out of jump pad, we need to be able to step
2696 over internal breakpoints and such. */
2697 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2699 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2701 lwp
= get_thread_lwp (current_thread
);
2706 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2707 || current_thread
->last_resume_kind
== resume_stop
)
2709 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2710 enqueue_one_deferred_signal (lwp
, &wstat
);
2715 find_inferior (&all_threads
, unsuspend_one_lwp
, NULL
);
2717 stabilizing_threads
= 0;
2719 current_thread
= saved_thread
;
2724 = (struct thread_info
*) find_inferior (&all_threads
,
2725 stuck_in_jump_pad_callback
,
2727 if (thread_stuck
!= NULL
)
2728 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
2729 lwpid_of (thread_stuck
));
2733 static void async_file_mark (void);
2735 /* Convenience function that is called when the kernel reports an
2736 event that is not passed out to GDB. */
2739 ignore_event (struct target_waitstatus
*ourstatus
)
2741 /* If we got an event, there may still be others, as a single
2742 SIGCHLD can indicate more than one child stopped. This forces
2743 another target_wait call. */
2746 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2750 /* Return non-zero if WAITSTATUS reflects an extended linux
2751 event. Otherwise, return zero. */
2754 extended_event_reported (const struct target_waitstatus
*waitstatus
)
2756 if (waitstatus
== NULL
)
2759 return (waitstatus
->kind
== TARGET_WAITKIND_FORKED
2760 || waitstatus
->kind
== TARGET_WAITKIND_VFORKED
2761 || waitstatus
->kind
== TARGET_WAITKIND_VFORK_DONE
);
2764 /* Wait for process, returns status. */
2767 linux_wait_1 (ptid_t ptid
,
2768 struct target_waitstatus
*ourstatus
, int target_options
)
2771 struct lwp_info
*event_child
;
2774 int step_over_finished
;
2775 int bp_explains_trap
;
2776 int maybe_internal_trap
;
2784 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid
));
2787 /* Translate generic target options into linux options. */
2789 if (target_options
& TARGET_WNOHANG
)
2792 bp_explains_trap
= 0;
2795 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2797 if (ptid_equal (step_over_bkpt
, null_ptid
))
2798 pid
= linux_wait_for_event (ptid
, &w
, options
);
2802 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
2803 target_pid_to_str (step_over_bkpt
));
2804 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2809 gdb_assert (target_options
& TARGET_WNOHANG
);
2813 debug_printf ("linux_wait_1 ret = null_ptid, "
2814 "TARGET_WAITKIND_IGNORE\n");
2818 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2825 debug_printf ("linux_wait_1 ret = null_ptid, "
2826 "TARGET_WAITKIND_NO_RESUMED\n");
2830 ourstatus
->kind
= TARGET_WAITKIND_NO_RESUMED
;
2834 event_child
= get_thread_lwp (current_thread
);
2836 /* linux_wait_for_event only returns an exit status for the last
2837 child of a process. Report it. */
2838 if (WIFEXITED (w
) || WIFSIGNALED (w
))
2842 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
2843 ourstatus
->value
.integer
= WEXITSTATUS (w
);
2847 debug_printf ("linux_wait_1 ret = %s, exited with "
2849 target_pid_to_str (ptid_of (current_thread
)),
2856 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
2857 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
2861 debug_printf ("linux_wait_1 ret = %s, terminated with "
2863 target_pid_to_str (ptid_of (current_thread
)),
2869 return ptid_of (current_thread
);
2872 /* If step-over executes a breakpoint instruction, it means a
2873 gdb/gdbserver breakpoint had been planted on top of a permanent
2874 breakpoint. The PC has been adjusted by
2875 check_stopped_by_breakpoint to point at the breakpoint address.
2876 Advance the PC manually past the breakpoint, otherwise the
2877 program would keep trapping the permanent breakpoint forever. */
2878 if (!ptid_equal (step_over_bkpt
, null_ptid
)
2879 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
)
2881 unsigned int increment_pc
= the_low_target
.breakpoint_len
;
2885 debug_printf ("step-over for %s executed software breakpoint\n",
2886 target_pid_to_str (ptid_of (current_thread
)));
2889 if (increment_pc
!= 0)
2891 struct regcache
*regcache
2892 = get_thread_regcache (current_thread
, 1);
2894 event_child
->stop_pc
+= increment_pc
;
2895 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
2897 if (!(*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))
2898 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2902 /* If this event was not handled before, and is not a SIGTRAP, we
2903 report it. SIGILL and SIGSEGV are also treated as traps in case
2904 a breakpoint is inserted at the current PC. If this target does
2905 not support internal breakpoints at all, we also report the
2906 SIGTRAP without further processing; it's of no concern to us. */
2908 = (supports_breakpoints ()
2909 && (WSTOPSIG (w
) == SIGTRAP
2910 || ((WSTOPSIG (w
) == SIGILL
2911 || WSTOPSIG (w
) == SIGSEGV
)
2912 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
2914 if (maybe_internal_trap
)
2916 /* Handle anything that requires bookkeeping before deciding to
2917 report the event or continue waiting. */
2919 /* First check if we can explain the SIGTRAP with an internal
2920 breakpoint, or if we should possibly report the event to GDB.
2921 Do this before anything that may remove or insert a
2923 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
2925 /* We have a SIGTRAP, possibly a step-over dance has just
2926 finished. If so, tweak the state machine accordingly,
2927 reinsert breakpoints and delete any reinsert (software
2928 single-step) breakpoints. */
2929 step_over_finished
= finish_step_over (event_child
);
2931 /* Now invoke the callbacks of any internal breakpoints there. */
2932 check_breakpoints (event_child
->stop_pc
);
2934 /* Handle tracepoint data collecting. This may overflow the
2935 trace buffer, and cause a tracing stop, removing
2937 trace_event
= handle_tracepoints (event_child
);
2939 if (bp_explains_trap
)
2941 /* If we stepped or ran into an internal breakpoint, we've
2942 already handled it. So next time we resume (from this
2943 PC), we should step over it. */
2945 debug_printf ("Hit a gdbserver breakpoint.\n");
2947 if (breakpoint_here (event_child
->stop_pc
))
2948 event_child
->need_step_over
= 1;
2953 /* We have some other signal, possibly a step-over dance was in
2954 progress, and it should be cancelled too. */
2955 step_over_finished
= finish_step_over (event_child
);
2958 /* We have all the data we need. Either report the event to GDB, or
2959 resume threads and keep waiting for more. */
2961 /* If we're collecting a fast tracepoint, finish the collection and
2962 move out of the jump pad before delivering a signal. See
2963 linux_stabilize_threads. */
2966 && WSTOPSIG (w
) != SIGTRAP
2967 && supports_fast_tracepoints ()
2968 && agent_loaded_p ())
2971 debug_printf ("Got signal %d for LWP %ld. Check if we need "
2972 "to defer or adjust it.\n",
2973 WSTOPSIG (w
), lwpid_of (current_thread
));
2975 /* Allow debugging the jump pad itself. */
2976 if (current_thread
->last_resume_kind
!= resume_step
2977 && maybe_move_out_of_jump_pad (event_child
, &w
))
2979 enqueue_one_deferred_signal (event_child
, &w
);
2982 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
2983 WSTOPSIG (w
), lwpid_of (current_thread
));
2985 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
2987 return ignore_event (ourstatus
);
2991 if (event_child
->collecting_fast_tracepoint
)
2994 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
2995 "Check if we're already there.\n",
2996 lwpid_of (current_thread
),
2997 event_child
->collecting_fast_tracepoint
);
3001 event_child
->collecting_fast_tracepoint
3002 = linux_fast_tracepoint_collecting (event_child
, NULL
);
3004 if (event_child
->collecting_fast_tracepoint
!= 1)
3006 /* No longer need this breakpoint. */
3007 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
3010 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3011 "stopping all threads momentarily.\n");
3013 /* Other running threads could hit this breakpoint.
3014 We don't handle moribund locations like GDB does,
3015 instead we always pause all threads when removing
3016 breakpoints, so that any step-over or
3017 decr_pc_after_break adjustment is always taken
3018 care of while the breakpoint is still
3020 stop_all_lwps (1, event_child
);
3022 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
3023 event_child
->exit_jump_pad_bkpt
= NULL
;
3025 unstop_all_lwps (1, event_child
);
3027 gdb_assert (event_child
->suspended
>= 0);
3031 if (event_child
->collecting_fast_tracepoint
== 0)
3034 debug_printf ("fast tracepoint finished "
3035 "collecting successfully.\n");
3037 /* We may have a deferred signal to report. */
3038 if (dequeue_one_deferred_signal (event_child
, &w
))
3041 debug_printf ("dequeued one signal.\n");
3046 debug_printf ("no deferred signals.\n");
3048 if (stabilizing_threads
)
3050 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3051 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3055 debug_printf ("linux_wait_1 ret = %s, stopped "
3056 "while stabilizing threads\n",
3057 target_pid_to_str (ptid_of (current_thread
)));
3061 return ptid_of (current_thread
);
3067 /* Check whether GDB would be interested in this event. */
3069 /* If GDB is not interested in this signal, don't stop other
3070 threads, and don't report it to GDB. Just resume the inferior
3071 right away. We do this for threading-related signals as well as
3072 any that GDB specifically requested we ignore. But never ignore
3073 SIGSTOP if we sent it ourselves, and do not ignore signals when
3074 stepping - they may require special handling to skip the signal
3075 handler. Also never ignore signals that could be caused by a
3077 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
3080 && current_thread
->last_resume_kind
!= resume_step
3082 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3083 (current_process ()->priv
->thread_db
!= NULL
3084 && (WSTOPSIG (w
) == __SIGRTMIN
3085 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
3088 (pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
3089 && !(WSTOPSIG (w
) == SIGSTOP
3090 && current_thread
->last_resume_kind
== resume_stop
)
3091 && !linux_wstatus_maybe_breakpoint (w
))))
3093 siginfo_t info
, *info_p
;
3096 debug_printf ("Ignored signal %d for LWP %ld.\n",
3097 WSTOPSIG (w
), lwpid_of (current_thread
));
3099 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
3100 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
3104 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3105 WSTOPSIG (w
), info_p
);
3106 return ignore_event (ourstatus
);
3109 /* Note that all addresses are always "out of the step range" when
3110 there's no range to begin with. */
3111 in_step_range
= lwp_in_step_range (event_child
);
3113 /* If GDB wanted this thread to single step, and the thread is out
3114 of the step range, we always want to report the SIGTRAP, and let
3115 GDB handle it. Watchpoints should always be reported. So should
3116 signals we can't explain. A SIGTRAP we can't explain could be a
3117 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3118 do, we're be able to handle GDB breakpoints on top of internal
3119 breakpoints, by handling the internal breakpoint and still
3120 reporting the event to GDB. If we don't, we're out of luck, GDB
3121 won't see the breakpoint hit. */
3122 report_to_gdb
= (!maybe_internal_trap
3123 || (current_thread
->last_resume_kind
== resume_step
3125 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3126 || (!step_over_finished
&& !in_step_range
3127 && !bp_explains_trap
&& !trace_event
)
3128 || (gdb_breakpoint_here (event_child
->stop_pc
)
3129 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
3130 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
))
3131 || extended_event_reported (&event_child
->waitstatus
));
3133 run_breakpoint_commands (event_child
->stop_pc
);
3135 /* We found no reason GDB would want us to stop. We either hit one
3136 of our own breakpoints, or finished an internal step GDB
3137 shouldn't know about. */
3142 if (bp_explains_trap
)
3143 debug_printf ("Hit a gdbserver breakpoint.\n");
3144 if (step_over_finished
)
3145 debug_printf ("Step-over finished.\n");
3147 debug_printf ("Tracepoint event.\n");
3148 if (lwp_in_step_range (event_child
))
3149 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3150 paddress (event_child
->stop_pc
),
3151 paddress (event_child
->step_range_start
),
3152 paddress (event_child
->step_range_end
));
3153 if (extended_event_reported (&event_child
->waitstatus
))
3155 char *str
= target_waitstatus_to_string (ourstatus
);
3156 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3157 lwpid_of (get_lwp_thread (event_child
)), str
);
3162 /* We're not reporting this breakpoint to GDB, so apply the
3163 decr_pc_after_break adjustment to the inferior's regcache
3166 if (the_low_target
.set_pc
!= NULL
)
3168 struct regcache
*regcache
3169 = get_thread_regcache (current_thread
, 1);
3170 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3173 /* We may have finished stepping over a breakpoint. If so,
3174 we've stopped and suspended all LWPs momentarily except the
3175 stepping one. This is where we resume them all again. We're
3176 going to keep waiting, so use proceed, which handles stepping
3177 over the next breakpoint. */
3179 debug_printf ("proceeding all threads.\n");
3181 if (step_over_finished
)
3182 unsuspend_all_lwps (event_child
);
3184 proceed_all_lwps ();
3185 return ignore_event (ourstatus
);
3190 if (current_thread
->last_resume_kind
== resume_step
)
3192 if (event_child
->step_range_start
== event_child
->step_range_end
)
3193 debug_printf ("GDB wanted to single-step, reporting event.\n");
3194 else if (!lwp_in_step_range (event_child
))
3195 debug_printf ("Out of step range, reporting event.\n");
3197 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
3198 debug_printf ("Stopped by watchpoint.\n");
3199 else if (gdb_breakpoint_here (event_child
->stop_pc
))
3200 debug_printf ("Stopped by GDB breakpoint.\n");
3202 debug_printf ("Hit a non-gdbserver trap event.\n");
3205 /* Alright, we're going to report a stop. */
3207 if (!stabilizing_threads
)
3209 /* In all-stop, stop all threads. */
3211 stop_all_lwps (0, NULL
);
3213 /* If we're not waiting for a specific LWP, choose an event LWP
3214 from among those that have had events. Giving equal priority
3215 to all LWPs that have had events helps prevent
3217 if (ptid_equal (ptid
, minus_one_ptid
))
3219 event_child
->status_pending_p
= 1;
3220 event_child
->status_pending
= w
;
3222 select_event_lwp (&event_child
);
3224 /* current_thread and event_child must stay in sync. */
3225 current_thread
= get_lwp_thread (event_child
);
3227 event_child
->status_pending_p
= 0;
3228 w
= event_child
->status_pending
;
3231 if (step_over_finished
)
3235 /* If we were doing a step-over, all other threads but
3236 the stepping one had been paused in start_step_over,
3237 with their suspend counts incremented. We don't want
3238 to do a full unstop/unpause, because we're in
3239 all-stop mode (so we want threads stopped), but we
3240 still need to unsuspend the other threads, to
3241 decrement their `suspended' count back. */
3242 unsuspend_all_lwps (event_child
);
3246 /* If we just finished a step-over, then all threads had
3247 been momentarily paused. In all-stop, that's fine,
3248 we want threads stopped by now anyway. In non-stop,
3249 we need to re-resume threads that GDB wanted to be
3251 unstop_all_lwps (1, event_child
);
3255 /* Stabilize threads (move out of jump pads). */
3257 stabilize_threads ();
3261 /* If we just finished a step-over, then all threads had been
3262 momentarily paused. In all-stop, that's fine, we want
3263 threads stopped by now anyway. In non-stop, we need to
3264 re-resume threads that GDB wanted to be running. */
3265 if (step_over_finished
)
3266 unstop_all_lwps (1, event_child
);
3269 if (extended_event_reported (&event_child
->waitstatus
))
3271 /* If the reported event is a fork, vfork or exec, let GDB know. */
3272 ourstatus
->kind
= event_child
->waitstatus
.kind
;
3273 ourstatus
->value
= event_child
->waitstatus
.value
;
3275 /* Clear the event lwp's waitstatus since we handled it already. */
3276 event_child
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3279 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3281 /* Now that we've selected our final event LWP, un-adjust its PC if
3282 it was a software breakpoint, and the client doesn't know we can
3283 adjust the breakpoint ourselves. */
3284 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3285 && !swbreak_feature
)
3287 int decr_pc
= the_low_target
.decr_pc_after_break
;
3291 struct regcache
*regcache
3292 = get_thread_regcache (current_thread
, 1);
3293 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
+ decr_pc
);
3297 if (current_thread
->last_resume_kind
== resume_stop
3298 && WSTOPSIG (w
) == SIGSTOP
)
3300 /* A thread that has been requested to stop by GDB with vCont;t,
3301 and it stopped cleanly, so report as SIG0. The use of
3302 SIGSTOP is an implementation detail. */
3303 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3305 else if (current_thread
->last_resume_kind
== resume_stop
3306 && WSTOPSIG (w
) != SIGSTOP
)
3308 /* A thread that has been requested to stop by GDB with vCont;t,
3309 but, it stopped for other reasons. */
3310 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3312 else if (ourstatus
->kind
== TARGET_WAITKIND_STOPPED
)
3314 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3317 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
3321 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3322 target_pid_to_str (ptid_of (current_thread
)),
3323 ourstatus
->kind
, ourstatus
->value
.sig
);
3327 return ptid_of (current_thread
);
3330 /* Get rid of any pending event in the pipe. */
3332 async_file_flush (void)
3338 ret
= read (linux_event_pipe
[0], &buf
, 1);
3339 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3342 /* Put something in the pipe, so the event loop wakes up. */
3344 async_file_mark (void)
3348 async_file_flush ();
3351 ret
= write (linux_event_pipe
[1], "+", 1);
3352 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3354 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3355 be awakened anyway. */
3359 linux_wait (ptid_t ptid
,
3360 struct target_waitstatus
*ourstatus
, int target_options
)
3364 /* Flush the async file first. */
3365 if (target_is_async_p ())
3366 async_file_flush ();
3370 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
3372 while ((target_options
& TARGET_WNOHANG
) == 0
3373 && ptid_equal (event_ptid
, null_ptid
)
3374 && ourstatus
->kind
== TARGET_WAITKIND_IGNORE
);
3376 /* If at least one stop was reported, there may be more. A single
3377 SIGCHLD can signal more than one child stop. */
3378 if (target_is_async_p ()
3379 && (target_options
& TARGET_WNOHANG
) != 0
3380 && !ptid_equal (event_ptid
, null_ptid
))
3386 /* Send a signal to an LWP. */
3389 kill_lwp (unsigned long lwpid
, int signo
)
3391 /* Use tkill, if possible, in case we are using nptl threads. If tkill
3392 fails, then we are not using nptl threads and we should be using kill. */
3396 static int tkill_failed
;
3403 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3404 if (errno
!= ENOSYS
)
3411 return kill (lwpid
, signo
);
3415 linux_stop_lwp (struct lwp_info
*lwp
)
3421 send_sigstop (struct lwp_info
*lwp
)
3425 pid
= lwpid_of (get_lwp_thread (lwp
));
3427 /* If we already have a pending stop signal for this process, don't
3429 if (lwp
->stop_expected
)
3432 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
3438 debug_printf ("Sending sigstop to lwp %d\n", pid
);
3440 lwp
->stop_expected
= 1;
3441 kill_lwp (pid
, SIGSTOP
);
3445 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
3447 struct thread_info
*thread
= (struct thread_info
*) entry
;
3448 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3450 /* Ignore EXCEPT. */
3461 /* Increment the suspend count of an LWP, and stop it, if not stopped
3464 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
3467 struct thread_info
*thread
= (struct thread_info
*) entry
;
3468 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3470 /* Ignore EXCEPT. */
3476 return send_sigstop_callback (entry
, except
);
3480 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3482 /* It's dead, really. */
3485 /* Store the exit status for later. */
3486 lwp
->status_pending_p
= 1;
3487 lwp
->status_pending
= wstat
;
3489 /* Prevent trying to stop it. */
3492 /* No further stops are expected from a dead lwp. */
3493 lwp
->stop_expected
= 0;
3496 /* Wait for all children to stop for the SIGSTOPs we just queued. */
3499 wait_for_sigstop (void)
3501 struct thread_info
*saved_thread
;
3506 saved_thread
= current_thread
;
3507 if (saved_thread
!= NULL
)
3508 saved_tid
= saved_thread
->entry
.id
;
3510 saved_tid
= null_ptid
; /* avoid bogus unused warning */
3513 debug_printf ("wait_for_sigstop: pulling events\n");
3515 /* Passing NULL_PTID as filter indicates we want all events to be
3516 left pending. Eventually this returns when there are no
3517 unwaited-for children left. */
3518 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
3520 gdb_assert (ret
== -1);
3522 if (saved_thread
== NULL
|| linux_thread_alive (saved_tid
))
3523 current_thread
= saved_thread
;
3527 debug_printf ("Previously current thread died.\n");
3531 /* We can't change the current inferior behind GDB's back,
3532 otherwise, a subsequent command may apply to the wrong
3534 current_thread
= NULL
;
3538 /* Set a valid thread as current. */
3539 set_desired_thread (0);
3544 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3545 move it out, because we need to report the stop event to GDB. For
3546 example, if the user puts a breakpoint in the jump pad, it's
3547 because she wants to debug it. */
3550 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
3552 struct thread_info
*thread
= (struct thread_info
*) entry
;
3553 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3555 gdb_assert (lwp
->suspended
== 0);
3556 gdb_assert (lwp
->stopped
);
3558 /* Allow debugging the jump pad, gdb_collect, etc.. */
3559 return (supports_fast_tracepoints ()
3560 && agent_loaded_p ()
3561 && (gdb_breakpoint_here (lwp
->stop_pc
)
3562 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3563 || thread
->last_resume_kind
== resume_step
)
3564 && linux_fast_tracepoint_collecting (lwp
, NULL
));
3568 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
3570 struct thread_info
*thread
= (struct thread_info
*) entry
;
3571 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3574 gdb_assert (lwp
->suspended
== 0);
3575 gdb_assert (lwp
->stopped
);
3577 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3579 /* Allow debugging the jump pad, gdb_collect, etc. */
3580 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3581 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
3582 && thread
->last_resume_kind
!= resume_step
3583 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3586 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
3591 lwp
->status_pending_p
= 0;
3592 enqueue_one_deferred_signal (lwp
, wstat
);
3595 debug_printf ("Signal %d for LWP %ld deferred "
3597 WSTOPSIG (*wstat
), lwpid_of (thread
));
3600 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
3607 lwp_running (struct inferior_list_entry
*entry
, void *data
)
3609 struct thread_info
*thread
= (struct thread_info
*) entry
;
3610 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3619 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
3620 If SUSPEND, then also increase the suspend count of every LWP,
3624 stop_all_lwps (int suspend
, struct lwp_info
*except
)
3626 /* Should not be called recursively. */
3627 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
3632 debug_printf ("stop_all_lwps (%s, except=%s)\n",
3633 suspend
? "stop-and-suspend" : "stop",
3635 ? target_pid_to_str (ptid_of (get_lwp_thread (except
)))
3639 stopping_threads
= (suspend
3640 ? STOPPING_AND_SUSPENDING_THREADS
3641 : STOPPING_THREADS
);
3644 find_inferior (&all_threads
, suspend_and_send_sigstop_callback
, except
);
3646 find_inferior (&all_threads
, send_sigstop_callback
, except
);
3647 wait_for_sigstop ();
3648 stopping_threads
= NOT_STOPPING_THREADS
;
3652 debug_printf ("stop_all_lwps done, setting stopping_threads "
3653 "back to !stopping\n");
3658 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
3659 SIGNAL is nonzero, give it that signal. */
3662 linux_resume_one_lwp_throw (struct lwp_info
*lwp
,
3663 int step
, int signal
, siginfo_t
*info
)
3665 struct thread_info
*thread
= get_lwp_thread (lwp
);
3666 struct thread_info
*saved_thread
;
3667 int fast_tp_collecting
;
3668 struct process_info
*proc
= get_thread_process (thread
);
3670 /* Note that target description may not be initialised
3671 (proc->tdesc == NULL) at this point because the program hasn't
3672 stopped at the first instruction yet. It means GDBserver skips
3673 the extra traps from the wrapper program (see option --wrapper).
3674 Code in this function that requires register access should be
3675 guarded by proc->tdesc == NULL or something else. */
3677 if (lwp
->stopped
== 0)
3680 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
3682 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
3684 /* Cancel actions that rely on GDB not changing the PC (e.g., the
3685 user used the "jump" command, or "set $pc = foo"). */
3686 if (thread
->while_stepping
!= NULL
&& lwp
->stop_pc
!= get_pc (lwp
))
3688 /* Collecting 'while-stepping' actions doesn't make sense
3690 release_while_stepping_state_list (thread
);
3693 /* If we have pending signals or status, and a new signal, enqueue the
3694 signal. Also enqueue the signal if we are waiting to reinsert a
3695 breakpoint; it will be picked up again below. */
3697 && (lwp
->status_pending_p
3698 || lwp
->pending_signals
!= NULL
3699 || lwp
->bp_reinsert
!= 0
3700 || fast_tp_collecting
))
3702 struct pending_signals
*p_sig
;
3703 p_sig
= xmalloc (sizeof (*p_sig
));
3704 p_sig
->prev
= lwp
->pending_signals
;
3705 p_sig
->signal
= signal
;
3707 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3709 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
3710 lwp
->pending_signals
= p_sig
;
3713 if (lwp
->status_pending_p
)
3716 debug_printf ("Not resuming lwp %ld (%s, signal %d, stop %s);"
3717 " has pending status\n",
3718 lwpid_of (thread
), step
? "step" : "continue", signal
,
3719 lwp
->stop_expected
? "expected" : "not expected");
3723 saved_thread
= current_thread
;
3724 current_thread
= thread
;
3727 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
3728 lwpid_of (thread
), step
? "step" : "continue", signal
,
3729 lwp
->stop_expected
? "expected" : "not expected");
3731 /* This bit needs some thinking about. If we get a signal that
3732 we must report while a single-step reinsert is still pending,
3733 we often end up resuming the thread. It might be better to
3734 (ew) allow a stack of pending events; then we could be sure that
3735 the reinsert happened right away and not lose any signals.
3737 Making this stack would also shrink the window in which breakpoints are
3738 uninserted (see comment in linux_wait_for_lwp) but not enough for
3739 complete correctness, so it won't solve that problem. It may be
3740 worthwhile just to solve this one, however. */
3741 if (lwp
->bp_reinsert
!= 0)
3744 debug_printf (" pending reinsert at 0x%s\n",
3745 paddress (lwp
->bp_reinsert
));
3747 if (can_hardware_single_step ())
3749 if (fast_tp_collecting
== 0)
3752 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
3754 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
3761 /* Postpone any pending signal. It was enqueued above. */
3765 if (fast_tp_collecting
== 1)
3768 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
3769 " (exit-jump-pad-bkpt)\n",
3772 /* Postpone any pending signal. It was enqueued above. */
3775 else if (fast_tp_collecting
== 2)
3778 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
3779 " single-stepping\n",
3782 if (can_hardware_single_step ())
3786 internal_error (__FILE__
, __LINE__
,
3787 "moving out of jump pad single-stepping"
3788 " not implemented on this target");
3791 /* Postpone any pending signal. It was enqueued above. */
3795 /* If we have while-stepping actions in this thread set it stepping.
3796 If we have a signal to deliver, it may or may not be set to
3797 SIG_IGN, we don't know. Assume so, and allow collecting
3798 while-stepping into a signal handler. A possible smart thing to
3799 do would be to set an internal breakpoint at the signal return
3800 address, continue, and carry on catching this while-stepping
3801 action only when that breakpoint is hit. A future
3803 if (thread
->while_stepping
!= NULL
3804 && can_hardware_single_step ())
3807 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
3812 if (proc
->tdesc
!= NULL
&& the_low_target
.get_pc
!= NULL
)
3814 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
3816 lwp
->stop_pc
= (*the_low_target
.get_pc
) (regcache
);
3820 debug_printf (" %s from pc 0x%lx\n", step
? "step" : "continue",
3821 (long) lwp
->stop_pc
);
3825 /* If we have pending signals, consume one unless we are trying to
3826 reinsert a breakpoint or we're trying to finish a fast tracepoint
3828 if (lwp
->pending_signals
!= NULL
3829 && lwp
->bp_reinsert
== 0
3830 && fast_tp_collecting
== 0)
3832 struct pending_signals
**p_sig
;
3834 p_sig
= &lwp
->pending_signals
;
3835 while ((*p_sig
)->prev
!= NULL
)
3836 p_sig
= &(*p_sig
)->prev
;
3838 signal
= (*p_sig
)->signal
;
3839 if ((*p_sig
)->info
.si_signo
!= 0)
3840 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
3847 if (the_low_target
.prepare_to_resume
!= NULL
)
3848 the_low_target
.prepare_to_resume (lwp
);
3850 regcache_invalidate_thread (thread
);
3852 lwp
->stepping
= step
;
3853 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (thread
),
3854 (PTRACE_TYPE_ARG3
) 0,
3855 /* Coerce to a uintptr_t first to avoid potential gcc warning
3856 of coercing an 8 byte integer to a 4 byte pointer. */
3857 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
3859 current_thread
= saved_thread
;
3861 perror_with_name ("resuming thread");
3863 /* Successfully resumed. Clear state that no longer makes sense,
3864 and mark the LWP as running. Must not do this before resuming
3865 otherwise if that fails other code will be confused. E.g., we'd
3866 later try to stop the LWP and hang forever waiting for a stop
3867 status. Note that we must not throw after this is cleared,
3868 otherwise handle_zombie_lwp_error would get confused. */
3870 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3873 /* Called when we try to resume a stopped LWP and that errors out. If
3874 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
3875 or about to become), discard the error, clear any pending status
3876 the LWP may have, and return true (we'll collect the exit status
3877 soon enough). Otherwise, return false. */
3880 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
3882 struct thread_info
*thread
= get_lwp_thread (lp
);
3884 /* If we get an error after resuming the LWP successfully, we'd
3885 confuse !T state for the LWP being gone. */
3886 gdb_assert (lp
->stopped
);
3888 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
3889 because even if ptrace failed with ESRCH, the tracee may be "not
3890 yet fully dead", but already refusing ptrace requests. In that
3891 case the tracee has 'R (Running)' state for a little bit
3892 (observed in Linux 3.18). See also the note on ESRCH in the
3893 ptrace(2) man page. Instead, check whether the LWP has any state
3894 other than ptrace-stopped. */
3896 /* Don't assume anything if /proc/PID/status can't be read. */
3897 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
3899 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3900 lp
->status_pending_p
= 0;
3906 /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
3907 disappears while we try to resume it. */
3910 linux_resume_one_lwp (struct lwp_info
*lwp
,
3911 int step
, int signal
, siginfo_t
*info
)
3915 linux_resume_one_lwp_throw (lwp
, step
, signal
, info
);
3917 CATCH (ex
, RETURN_MASK_ERROR
)
3919 if (!check_ptrace_stopped_lwp_gone (lwp
))
3920 throw_exception (ex
);
3925 struct thread_resume_array
3927 struct thread_resume
*resume
;
3931 /* This function is called once per thread via find_inferior.
3932 ARG is a pointer to a thread_resume_array struct.
3933 We look up the thread specified by ENTRY in ARG, and mark the thread
3934 with a pointer to the appropriate resume request.
3936 This algorithm is O(threads * resume elements), but resume elements
3937 is small (and will remain small at least until GDB supports thread
3941 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
3943 struct thread_info
*thread
= (struct thread_info
*) entry
;
3944 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3946 struct thread_resume_array
*r
;
3950 for (ndx
= 0; ndx
< r
->n
; ndx
++)
3952 ptid_t ptid
= r
->resume
[ndx
].thread
;
3953 if (ptid_equal (ptid
, minus_one_ptid
)
3954 || ptid_equal (ptid
, entry
->id
)
3955 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
3957 || (ptid_get_pid (ptid
) == pid_of (thread
)
3958 && (ptid_is_pid (ptid
)
3959 || ptid_get_lwp (ptid
) == -1)))
3961 if (r
->resume
[ndx
].kind
== resume_stop
3962 && thread
->last_resume_kind
== resume_stop
)
3965 debug_printf ("already %s LWP %ld at GDB's request\n",
3966 (thread
->last_status
.kind
3967 == TARGET_WAITKIND_STOPPED
)
3975 lwp
->resume
= &r
->resume
[ndx
];
3976 thread
->last_resume_kind
= lwp
->resume
->kind
;
3978 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
3979 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
3981 /* If we had a deferred signal to report, dequeue one now.
3982 This can happen if LWP gets more than one signal while
3983 trying to get out of a jump pad. */
3985 && !lwp
->status_pending_p
3986 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
3988 lwp
->status_pending_p
= 1;
3991 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
3992 "leaving status pending.\n",
3993 WSTOPSIG (lwp
->status_pending
),
4001 /* No resume action for this thread. */
4007 /* find_inferior callback for linux_resume.
4008 Set *FLAG_P if this lwp has an interesting status pending. */
4011 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
4013 struct thread_info
*thread
= (struct thread_info
*) entry
;
4014 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4016 /* LWPs which will not be resumed are not interesting, because
4017 we might not wait for them next time through linux_wait. */
4018 if (lwp
->resume
== NULL
)
4021 if (thread_still_has_status_pending_p (thread
))
4022 * (int *) flag_p
= 1;
4027 /* Return 1 if this lwp that GDB wants running is stopped at an
4028 internal breakpoint that we need to step over. It assumes that any
4029 required STOP_PC adjustment has already been propagated to the
4030 inferior's regcache. */
4033 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
4035 struct thread_info
*thread
= (struct thread_info
*) entry
;
4036 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4037 struct thread_info
*saved_thread
;
4039 struct process_info
*proc
= get_thread_process (thread
);
4041 /* GDBserver is skipping the extra traps from the wrapper program,
4042 don't have to do step over. */
4043 if (proc
->tdesc
== NULL
)
4046 /* LWPs which will not be resumed are not interesting, because we
4047 might not wait for them next time through linux_wait. */
4052 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4057 if (thread
->last_resume_kind
== resume_stop
)
4060 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4066 gdb_assert (lwp
->suspended
>= 0);
4071 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4076 if (!lwp
->need_step_over
)
4079 debug_printf ("Need step over [LWP %ld]? No\n", lwpid_of (thread
));
4082 if (lwp
->status_pending_p
)
4085 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4091 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4095 /* If the PC has changed since we stopped, then don't do anything,
4096 and let the breakpoint/tracepoint be hit. This happens if, for
4097 instance, GDB handled the decr_pc_after_break subtraction itself,
4098 GDB is OOL stepping this thread, or the user has issued a "jump"
4099 command, or poked thread's registers herself. */
4100 if (pc
!= lwp
->stop_pc
)
4103 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4104 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4106 paddress (lwp
->stop_pc
), paddress (pc
));
4108 lwp
->need_step_over
= 0;
4112 saved_thread
= current_thread
;
4113 current_thread
= thread
;
4115 /* We can only step over breakpoints we know about. */
4116 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
4118 /* Don't step over a breakpoint that GDB expects to hit
4119 though. If the condition is being evaluated on the target's side
4120 and it evaluate to false, step over this breakpoint as well. */
4121 if (gdb_breakpoint_here (pc
)
4122 && gdb_condition_true_at_breakpoint (pc
)
4123 && gdb_no_commands_at_breakpoint (pc
))
4126 debug_printf ("Need step over [LWP %ld]? yes, but found"
4127 " GDB breakpoint at 0x%s; skipping step over\n",
4128 lwpid_of (thread
), paddress (pc
));
4130 current_thread
= saved_thread
;
4136 debug_printf ("Need step over [LWP %ld]? yes, "
4137 "found breakpoint at 0x%s\n",
4138 lwpid_of (thread
), paddress (pc
));
4140 /* We've found an lwp that needs stepping over --- return 1 so
4141 that find_inferior stops looking. */
4142 current_thread
= saved_thread
;
4144 /* If the step over is cancelled, this is set again. */
4145 lwp
->need_step_over
= 0;
4150 current_thread
= saved_thread
;
4153 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4155 lwpid_of (thread
), paddress (pc
));
4160 /* Start a step-over operation on LWP. When LWP stopped at a
4161 breakpoint, to make progress, we need to remove the breakpoint out
4162 of the way. If we let other threads run while we do that, they may
4163 pass by the breakpoint location and miss hitting it. To avoid
4164 that, a step-over momentarily stops all threads while LWP is
4165 single-stepped while the breakpoint is temporarily uninserted from
4166 the inferior. When the single-step finishes, we reinsert the
4167 breakpoint, and let all threads that are supposed to be running,
4170 On targets that don't support hardware single-step, we don't
4171 currently support full software single-stepping. Instead, we only
4172 support stepping over the thread event breakpoint, by asking the
4173 low target where to place a reinsert breakpoint. Since this
4174 routine assumes the breakpoint being stepped over is a thread event
4175 breakpoint, it usually assumes the return address of the current
4176 function is a good enough place to set the reinsert breakpoint. */
4179 start_step_over (struct lwp_info
*lwp
)
4181 struct thread_info
*thread
= get_lwp_thread (lwp
);
4182 struct thread_info
*saved_thread
;
4187 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4190 stop_all_lwps (1, lwp
);
4191 gdb_assert (lwp
->suspended
== 0);
4194 debug_printf ("Done stopping all threads for step-over.\n");
4196 /* Note, we should always reach here with an already adjusted PC,
4197 either by GDB (if we're resuming due to GDB's request), or by our
4198 caller, if we just finished handling an internal breakpoint GDB
4199 shouldn't care about. */
4202 saved_thread
= current_thread
;
4203 current_thread
= thread
;
4205 lwp
->bp_reinsert
= pc
;
4206 uninsert_breakpoints_at (pc
);
4207 uninsert_fast_tracepoint_jumps_at (pc
);
4209 if (can_hardware_single_step ())
4215 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
4216 set_reinsert_breakpoint (raddr
);
4220 current_thread
= saved_thread
;
4222 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4224 /* Require next event from this LWP. */
4225 step_over_bkpt
= thread
->entry
.id
;
4229 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
4230 start_step_over, if still there, and delete any reinsert
4231 breakpoints we've set, on non hardware single-step targets. */
4234 finish_step_over (struct lwp_info
*lwp
)
4236 if (lwp
->bp_reinsert
!= 0)
4239 debug_printf ("Finished step over.\n");
4241 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4242 may be no breakpoint to reinsert there by now. */
4243 reinsert_breakpoints_at (lwp
->bp_reinsert
);
4244 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
4246 lwp
->bp_reinsert
= 0;
4248 /* Delete any software-single-step reinsert breakpoints. No
4249 longer needed. We don't have to worry about other threads
4250 hitting this trap, and later not being able to explain it,
4251 because we were stepping over a breakpoint, and we hold all
4252 threads but LWP stopped while doing that. */
4253 if (!can_hardware_single_step ())
4254 delete_reinsert_breakpoints ();
4256 step_over_bkpt
= null_ptid
;
4263 /* This function is called once per thread. We check the thread's resume
4264 request, which will tell us whether to resume, step, or leave the thread
4265 stopped; and what signal, if any, it should be sent.
4267 For threads which we aren't explicitly told otherwise, we preserve
4268 the stepping flag; this is used for stepping over gdbserver-placed
4271 If pending_flags was set in any thread, we queue any needed
4272 signals, since we won't actually resume. We already have a pending
4273 event to report, so we don't need to preserve any step requests;
4274 they should be re-issued if necessary. */
4277 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
4279 struct thread_info
*thread
= (struct thread_info
*) entry
;
4280 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4282 int leave_all_stopped
= * (int *) arg
;
4285 if (lwp
->resume
== NULL
)
4288 if (lwp
->resume
->kind
== resume_stop
)
4291 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread
));
4296 debug_printf ("stopping LWP %ld\n", lwpid_of (thread
));
4298 /* Stop the thread, and wait for the event asynchronously,
4299 through the event loop. */
4305 debug_printf ("already stopped LWP %ld\n",
4308 /* The LWP may have been stopped in an internal event that
4309 was not meant to be notified back to GDB (e.g., gdbserver
4310 breakpoint), so we should be reporting a stop event in
4313 /* If the thread already has a pending SIGSTOP, this is a
4314 no-op. Otherwise, something later will presumably resume
4315 the thread and this will cause it to cancel any pending
4316 operation, due to last_resume_kind == resume_stop. If
4317 the thread already has a pending status to report, we
4318 will still report it the next time we wait - see
4319 status_pending_p_callback. */
4321 /* If we already have a pending signal to report, then
4322 there's no need to queue a SIGSTOP, as this means we're
4323 midway through moving the LWP out of the jumppad, and we
4324 will report the pending signal as soon as that is
4326 if (lwp
->pending_signals_to_report
== NULL
)
4330 /* For stop requests, we're done. */
4332 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4336 /* If this thread which is about to be resumed has a pending status,
4337 then don't resume any threads - we can just report the pending
4338 status. Make sure to queue any signals that would otherwise be
4339 sent. In all-stop mode, we do this decision based on if *any*
4340 thread has a pending status. If there's a thread that needs the
4341 step-over-breakpoint dance, then don't resume any other thread
4342 but that particular one. */
4343 leave_pending
= (lwp
->status_pending_p
|| leave_all_stopped
);
4348 debug_printf ("resuming LWP %ld\n", lwpid_of (thread
));
4350 step
= (lwp
->resume
->kind
== resume_step
);
4351 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
4356 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread
));
4358 /* If we have a new signal, enqueue the signal. */
4359 if (lwp
->resume
->sig
!= 0)
4361 struct pending_signals
*p_sig
;
4362 p_sig
= xmalloc (sizeof (*p_sig
));
4363 p_sig
->prev
= lwp
->pending_signals
;
4364 p_sig
->signal
= lwp
->resume
->sig
;
4365 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
4367 /* If this is the same signal we were previously stopped by,
4368 make sure to queue its siginfo. We can ignore the return
4369 value of ptrace; if it fails, we'll skip
4370 PTRACE_SETSIGINFO. */
4371 if (WIFSTOPPED (lwp
->last_status
)
4372 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
4373 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4376 lwp
->pending_signals
= p_sig
;
4380 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4386 linux_resume (struct thread_resume
*resume_info
, size_t n
)
4388 struct thread_resume_array array
= { resume_info
, n
};
4389 struct thread_info
*need_step_over
= NULL
;
4391 int leave_all_stopped
;
4396 debug_printf ("linux_resume:\n");
4399 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
4401 /* If there is a thread which would otherwise be resumed, which has
4402 a pending status, then don't resume any threads - we can just
4403 report the pending status. Make sure to queue any signals that
4404 would otherwise be sent. In non-stop mode, we'll apply this
4405 logic to each thread individually. We consume all pending events
4406 before considering to start a step-over (in all-stop). */
4409 find_inferior (&all_threads
, resume_status_pending_p
, &any_pending
);
4411 /* If there is a thread which would otherwise be resumed, which is
4412 stopped at a breakpoint that needs stepping over, then don't
4413 resume any threads - have it step over the breakpoint with all
4414 other threads stopped, then resume all threads again. Make sure
4415 to queue any signals that would otherwise be delivered or
4417 if (!any_pending
&& supports_breakpoints ())
4419 = (struct thread_info
*) find_inferior (&all_threads
,
4420 need_step_over_p
, NULL
);
4422 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
4426 if (need_step_over
!= NULL
)
4427 debug_printf ("Not resuming all, need step over\n");
4428 else if (any_pending
)
4429 debug_printf ("Not resuming, all-stop and found "
4430 "an LWP with pending status\n");
4432 debug_printf ("Resuming, no pending status or step over needed\n");
4435 /* Even if we're leaving threads stopped, queue all signals we'd
4436 otherwise deliver. */
4437 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
4440 start_step_over (get_thread_lwp (need_step_over
));
4444 debug_printf ("linux_resume done\n");
4449 /* This function is called once per thread. We check the thread's
4450 last resume request, which will tell us whether to resume, step, or
4451 leave the thread stopped. Any signal the client requested to be
4452 delivered has already been enqueued at this point.
4454 If any thread that GDB wants running is stopped at an internal
4455 breakpoint that needs stepping over, we start a step-over operation
4456 on that particular thread, and leave all others stopped. */
4459 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
4461 struct thread_info
*thread
= (struct thread_info
*) entry
;
4462 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4469 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread
));
4474 debug_printf (" LWP %ld already running\n", lwpid_of (thread
));
4478 if (thread
->last_resume_kind
== resume_stop
4479 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
4482 debug_printf (" client wants LWP to remain %ld stopped\n",
4487 if (lwp
->status_pending_p
)
4490 debug_printf (" LWP %ld has pending status, leaving stopped\n",
4495 gdb_assert (lwp
->suspended
>= 0);
4500 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread
));
4504 if (thread
->last_resume_kind
== resume_stop
4505 && lwp
->pending_signals_to_report
== NULL
4506 && lwp
->collecting_fast_tracepoint
== 0)
4508 /* We haven't reported this LWP as stopped yet (otherwise, the
4509 last_status.kind check above would catch it, and we wouldn't
4510 reach here. This LWP may have been momentarily paused by a
4511 stop_all_lwps call while handling for example, another LWP's
4512 step-over. In that case, the pending expected SIGSTOP signal
4513 that was queued at vCont;t handling time will have already
4514 been consumed by wait_for_sigstop, and so we need to requeue
4515 another one here. Note that if the LWP already has a SIGSTOP
4516 pending, this is a no-op. */
4519 debug_printf ("Client wants LWP %ld to stop. "
4520 "Making sure it has a SIGSTOP pending\n",
4526 step
= thread
->last_resume_kind
== resume_step
;
4527 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4532 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
4534 struct thread_info
*thread
= (struct thread_info
*) entry
;
4535 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4541 gdb_assert (lwp
->suspended
>= 0);
4543 return proceed_one_lwp (entry
, except
);
4546 /* When we finish a step-over, set threads running again. If there's
4547 another thread that may need a step-over, now's the time to start
4548 it. Eventually, we'll move all threads past their breakpoints. */
4551 proceed_all_lwps (void)
4553 struct thread_info
*need_step_over
;
4555 /* If there is a thread which would otherwise be resumed, which is
4556 stopped at a breakpoint that needs stepping over, then don't
4557 resume any threads - have it step over the breakpoint with all
4558 other threads stopped, then resume all threads again. */
4560 if (supports_breakpoints ())
4563 = (struct thread_info
*) find_inferior (&all_threads
,
4564 need_step_over_p
, NULL
);
4566 if (need_step_over
!= NULL
)
4569 debug_printf ("proceed_all_lwps: found "
4570 "thread %ld needing a step-over\n",
4571 lwpid_of (need_step_over
));
4573 start_step_over (get_thread_lwp (need_step_over
));
4579 debug_printf ("Proceeding, no step-over needed\n");
4581 find_inferior (&all_threads
, proceed_one_lwp
, NULL
);
4584 /* Stopped LWPs that the client wanted to be running, that don't have
4585 pending statuses, are set to run again, except for EXCEPT, if not
4586 NULL. This undoes a stop_all_lwps call. */
4589 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
4595 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
4596 lwpid_of (get_lwp_thread (except
)));
4598 debug_printf ("unstopping all lwps\n");
4602 find_inferior (&all_threads
, unsuspend_and_proceed_one_lwp
, except
);
4604 find_inferior (&all_threads
, proceed_one_lwp
, except
);
4608 debug_printf ("unstop_all_lwps done\n");
4614 #ifdef HAVE_LINUX_REGSETS
4616 #define use_linux_regsets 1
4618 /* Returns true if REGSET has been disabled. */
4621 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
4623 return (info
->disabled_regsets
!= NULL
4624 && info
->disabled_regsets
[regset
- info
->regsets
]);
4627 /* Disable REGSET. */
4630 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
4634 dr_offset
= regset
- info
->regsets
;
4635 if (info
->disabled_regsets
== NULL
)
4636 info
->disabled_regsets
= xcalloc (1, info
->num_regsets
);
4637 info
->disabled_regsets
[dr_offset
] = 1;
4641 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
4642 struct regcache
*regcache
)
4644 struct regset_info
*regset
;
4645 int saw_general_regs
= 0;
4649 pid
= lwpid_of (current_thread
);
4650 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
4655 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
4658 buf
= xmalloc (regset
->size
);
4660 nt_type
= regset
->nt_type
;
4664 iov
.iov_len
= regset
->size
;
4665 data
= (void *) &iov
;
4671 res
= ptrace (regset
->get_request
, pid
,
4672 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4674 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4680 /* If we get EIO on a regset, do not try it again for
4681 this process mode. */
4682 disable_regset (regsets_info
, regset
);
4684 else if (errno
== ENODATA
)
4686 /* ENODATA may be returned if the regset is currently
4687 not "active". This can happen in normal operation,
4688 so suppress the warning in this case. */
4693 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
4700 if (regset
->type
== GENERAL_REGS
)
4701 saw_general_regs
= 1;
4702 regset
->store_function (regcache
, buf
);
4706 if (saw_general_regs
)
4713 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
4714 struct regcache
*regcache
)
4716 struct regset_info
*regset
;
4717 int saw_general_regs
= 0;
4721 pid
= lwpid_of (current_thread
);
4722 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
4727 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
4728 || regset
->fill_function
== NULL
)
4731 buf
= xmalloc (regset
->size
);
4733 /* First fill the buffer with the current register set contents,
4734 in case there are any items in the kernel's regset that are
4735 not in gdbserver's regcache. */
4737 nt_type
= regset
->nt_type
;
4741 iov
.iov_len
= regset
->size
;
4742 data
= (void *) &iov
;
4748 res
= ptrace (regset
->get_request
, pid
,
4749 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4751 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4756 /* Then overlay our cached registers on that. */
4757 regset
->fill_function (regcache
, buf
);
4759 /* Only now do we write the register set. */
4761 res
= ptrace (regset
->set_request
, pid
,
4762 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4764 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
4772 /* If we get EIO on a regset, do not try it again for
4773 this process mode. */
4774 disable_regset (regsets_info
, regset
);
4776 else if (errno
== ESRCH
)
4778 /* At this point, ESRCH should mean the process is
4779 already gone, in which case we simply ignore attempts
4780 to change its registers. See also the related
4781 comment in linux_resume_one_lwp. */
4787 perror ("Warning: ptrace(regsets_store_inferior_registers)");
4790 else if (regset
->type
== GENERAL_REGS
)
4791 saw_general_regs
= 1;
4794 if (saw_general_regs
)
4800 #else /* !HAVE_LINUX_REGSETS */
4802 #define use_linux_regsets 0
4803 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
4804 #define regsets_store_inferior_registers(regsets_info, regcache) 1
4808 /* Return 1 if register REGNO is supported by one of the regset ptrace
4809 calls or 0 if it has to be transferred individually. */
4812 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
4814 unsigned char mask
= 1 << (regno
% 8);
4815 size_t index
= regno
/ 8;
4817 return (use_linux_regsets
4818 && (regs_info
->regset_bitmap
== NULL
4819 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
4822 #ifdef HAVE_LINUX_USRREGS
4825 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
4829 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
4830 error ("Invalid register number %d.", regnum
);
4832 addr
= usrregs
->regmap
[regnum
];
4837 /* Fetch one register. */
4839 fetch_register (const struct usrregs_info
*usrregs
,
4840 struct regcache
*regcache
, int regno
)
4847 if (regno
>= usrregs
->num_regs
)
4849 if ((*the_low_target
.cannot_fetch_register
) (regno
))
4852 regaddr
= register_addr (usrregs
, regno
);
4856 size
= ((register_size (regcache
->tdesc
, regno
)
4857 + sizeof (PTRACE_XFER_TYPE
) - 1)
4858 & -sizeof (PTRACE_XFER_TYPE
));
4859 buf
= alloca (size
);
4861 pid
= lwpid_of (current_thread
);
4862 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4865 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
4866 ptrace (PTRACE_PEEKUSER
, pid
,
4867 /* Coerce to a uintptr_t first to avoid potential gcc warning
4868 of coercing an 8 byte integer to a 4 byte pointer. */
4869 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
4870 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4872 error ("reading register %d: %s", regno
, strerror (errno
));
4875 if (the_low_target
.supply_ptrace_register
)
4876 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
4878 supply_register (regcache
, regno
, buf
);
4881 /* Store one register. */
4883 store_register (const struct usrregs_info
*usrregs
,
4884 struct regcache
*regcache
, int regno
)
4891 if (regno
>= usrregs
->num_regs
)
4893 if ((*the_low_target
.cannot_store_register
) (regno
))
4896 regaddr
= register_addr (usrregs
, regno
);
4900 size
= ((register_size (regcache
->tdesc
, regno
)
4901 + sizeof (PTRACE_XFER_TYPE
) - 1)
4902 & -sizeof (PTRACE_XFER_TYPE
));
4903 buf
= alloca (size
);
4904 memset (buf
, 0, size
);
4906 if (the_low_target
.collect_ptrace_register
)
4907 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
4909 collect_register (regcache
, regno
, buf
);
4911 pid
= lwpid_of (current_thread
);
4912 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4915 ptrace (PTRACE_POKEUSER
, pid
,
4916 /* Coerce to a uintptr_t first to avoid potential gcc warning
4917 about coercing an 8 byte integer to a 4 byte pointer. */
4918 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
4919 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
4922 /* At this point, ESRCH should mean the process is
4923 already gone, in which case we simply ignore attempts
4924 to change its registers. See also the related
4925 comment in linux_resume_one_lwp. */
4929 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
4930 error ("writing register %d: %s", regno
, strerror (errno
));
4932 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4936 /* Fetch all registers, or just one, from the child process.
4937 If REGNO is -1, do this for all registers, skipping any that are
4938 assumed to have been retrieved by regsets_fetch_inferior_registers,
4939 unless ALL is non-zero.
4940 Otherwise, REGNO specifies which register (so we can save time). */
4942 usr_fetch_inferior_registers (const struct regs_info
*regs_info
,
4943 struct regcache
*regcache
, int regno
, int all
)
4945 struct usrregs_info
*usr
= regs_info
->usrregs
;
4949 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
4950 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
4951 fetch_register (usr
, regcache
, regno
);
4954 fetch_register (usr
, regcache
, regno
);
4957 /* Store our register values back into the inferior.
4958 If REGNO is -1, do this for all registers, skipping any that are
4959 assumed to have been saved by regsets_store_inferior_registers,
4960 unless ALL is non-zero.
4961 Otherwise, REGNO specifies which register (so we can save time). */
4963 usr_store_inferior_registers (const struct regs_info
*regs_info
,
4964 struct regcache
*regcache
, int regno
, int all
)
4966 struct usrregs_info
*usr
= regs_info
->usrregs
;
4970 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
4971 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
4972 store_register (usr
, regcache
, regno
);
4975 store_register (usr
, regcache
, regno
);
4978 #else /* !HAVE_LINUX_USRREGS */
4980 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
4981 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
4987 linux_fetch_registers (struct regcache
*regcache
, int regno
)
4991 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
4995 if (the_low_target
.fetch_register
!= NULL
4996 && regs_info
->usrregs
!= NULL
)
4997 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
4998 (*the_low_target
.fetch_register
) (regcache
, regno
);
5000 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
5001 if (regs_info
->usrregs
!= NULL
)
5002 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
5006 if (the_low_target
.fetch_register
!= NULL
5007 && (*the_low_target
.fetch_register
) (regcache
, regno
))
5010 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5012 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
5014 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5015 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
5020 linux_store_registers (struct regcache
*regcache
, int regno
)
5024 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5028 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5030 if (regs_info
->usrregs
!= NULL
)
5031 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
5035 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5037 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5039 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5040 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
5045 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5046 to debugger memory starting at MYADDR. */
5049 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
5051 int pid
= lwpid_of (current_thread
);
5052 register PTRACE_XFER_TYPE
*buffer
;
5053 register CORE_ADDR addr
;
5060 /* Try using /proc. Don't bother for one word. */
5061 if (len
>= 3 * sizeof (long))
5065 /* We could keep this file open and cache it - possibly one per
5066 thread. That requires some juggling, but is even faster. */
5067 sprintf (filename
, "/proc/%d/mem", pid
);
5068 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
5072 /* If pread64 is available, use it. It's faster if the kernel
5073 supports it (only one syscall), and it's 64-bit safe even on
5074 32-bit platforms (for instance, SPARC debugging a SPARC64
5077 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
5080 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
5081 bytes
= read (fd
, myaddr
, len
);
5088 /* Some data was read, we'll try to get the rest with ptrace. */
5098 /* Round starting address down to longword boundary. */
5099 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5100 /* Round ending address up; get number of longwords that makes. */
5101 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5102 / sizeof (PTRACE_XFER_TYPE
));
5103 /* Allocate buffer of that many longwords. */
5104 buffer
= (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
5106 /* Read all the longwords */
5108 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5110 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5111 about coercing an 8 byte integer to a 4 byte pointer. */
5112 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
5113 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5114 (PTRACE_TYPE_ARG4
) 0);
5120 /* Copy appropriate bytes out of the buffer. */
5123 i
*= sizeof (PTRACE_XFER_TYPE
);
5124 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
5126 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5133 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5134 memory at MEMADDR. On failure (cannot write to the inferior)
5135 returns the value of errno. Always succeeds if LEN is zero. */
5138 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
5141 /* Round starting address down to longword boundary. */
5142 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5143 /* Round ending address up; get number of longwords that makes. */
5145 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5146 / sizeof (PTRACE_XFER_TYPE
);
5148 /* Allocate buffer of that many longwords. */
5149 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*)
5150 alloca (count
* sizeof (PTRACE_XFER_TYPE
));
5152 int pid
= lwpid_of (current_thread
);
5156 /* Zero length write always succeeds. */
5162 /* Dump up to four bytes. */
5163 unsigned int val
= * (unsigned int *) myaddr
;
5169 val
= val
& 0xffffff;
5170 debug_printf ("Writing %0*x to 0x%08lx in process %d\n",
5171 2 * ((len
< 4) ? len
: 4), val
, (long)memaddr
, pid
);
5174 /* Fill start and end extra bytes of buffer with existing memory data. */
5177 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5178 about coercing an 8 byte integer to a 4 byte pointer. */
5179 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
5180 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5181 (PTRACE_TYPE_ARG4
) 0);
5189 = ptrace (PTRACE_PEEKTEXT
, pid
,
5190 /* Coerce to a uintptr_t first to avoid potential gcc warning
5191 about coercing an 8 byte integer to a 4 byte pointer. */
5192 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
5193 * sizeof (PTRACE_XFER_TYPE
)),
5194 (PTRACE_TYPE_ARG4
) 0);
5199 /* Copy data to be written over corresponding part of buffer. */
5201 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5204 /* Write the entire buffer. */
5206 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5209 ptrace (PTRACE_POKETEXT
, pid
,
5210 /* Coerce to a uintptr_t first to avoid potential gcc warning
5211 about coercing an 8 byte integer to a 4 byte pointer. */
5212 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5213 (PTRACE_TYPE_ARG4
) buffer
[i
]);
5222 linux_look_up_symbols (void)
5224 #ifdef USE_THREAD_DB
5225 struct process_info
*proc
= current_process ();
5227 if (proc
->priv
->thread_db
!= NULL
)
5230 /* If the kernel supports tracing clones, then we don't need to
5231 use the magic thread event breakpoint to learn about
5233 thread_db_init (!linux_supports_traceclone ());
5238 linux_request_interrupt (void)
5240 extern unsigned long signal_pid
;
5242 /* Send a SIGINT to the process group. This acts just like the user
5243 typed a ^C on the controlling terminal. */
5244 kill (-signal_pid
, SIGINT
);
5247 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5248 to debugger memory starting at MYADDR. */
5251 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
5253 char filename
[PATH_MAX
];
5255 int pid
= lwpid_of (current_thread
);
5257 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5259 fd
= open (filename
, O_RDONLY
);
5263 if (offset
!= (CORE_ADDR
) 0
5264 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5267 n
= read (fd
, myaddr
, len
);
5274 /* These breakpoint and watchpoint related wrapper functions simply
5275 pass on the function call if the target has registered a
5276 corresponding function. */
5279 linux_supports_z_point_type (char z_type
)
5281 return (the_low_target
.supports_z_point_type
!= NULL
5282 && the_low_target
.supports_z_point_type (z_type
));
5286 linux_insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5287 int size
, struct raw_breakpoint
*bp
)
5289 if (type
== raw_bkpt_type_sw
)
5290 return insert_memory_breakpoint (bp
);
5291 else if (the_low_target
.insert_point
!= NULL
)
5292 return the_low_target
.insert_point (type
, addr
, size
, bp
);
5294 /* Unsupported (see target.h). */
5299 linux_remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5300 int size
, struct raw_breakpoint
*bp
)
5302 if (type
== raw_bkpt_type_sw
)
5303 return remove_memory_breakpoint (bp
);
5304 else if (the_low_target
.remove_point
!= NULL
)
5305 return the_low_target
.remove_point (type
, addr
, size
, bp
);
5307 /* Unsupported (see target.h). */
5311 /* Implement the to_stopped_by_sw_breakpoint target_ops
5315 linux_stopped_by_sw_breakpoint (void)
5317 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5319 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
5322 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
5326 linux_supports_stopped_by_sw_breakpoint (void)
5328 return USE_SIGTRAP_SIGINFO
;
5331 /* Implement the to_stopped_by_hw_breakpoint target_ops
5335 linux_stopped_by_hw_breakpoint (void)
5337 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5339 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
5342 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
5346 linux_supports_stopped_by_hw_breakpoint (void)
5348 return USE_SIGTRAP_SIGINFO
;
5351 /* Implement the supports_conditional_breakpoints target_ops
5355 linux_supports_conditional_breakpoints (void)
5357 /* GDBserver needs to step over the breakpoint if the condition is
5358 false. GDBserver software single step is too simple, so disable
5359 conditional breakpoints if the target doesn't have hardware single
5361 return can_hardware_single_step ();
5365 linux_stopped_by_watchpoint (void)
5367 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5369 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
5373 linux_stopped_data_address (void)
5375 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5377 return lwp
->stopped_data_address
;
5380 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
5381 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
5382 && defined(PT_TEXT_END_ADDR)
5384 /* This is only used for targets that define PT_TEXT_ADDR,
5385 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5386 the target has different ways of acquiring this information, like
5389 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5390 to tell gdb about. */
5393 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
5395 unsigned long text
, text_end
, data
;
5396 int pid
= lwpid_of (current_thread
);
5400 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
5401 (PTRACE_TYPE_ARG4
) 0);
5402 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
5403 (PTRACE_TYPE_ARG4
) 0);
5404 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
5405 (PTRACE_TYPE_ARG4
) 0);
5409 /* Both text and data offsets produced at compile-time (and so
5410 used by gdb) are relative to the beginning of the program,
5411 with the data segment immediately following the text segment.
5412 However, the actual runtime layout in memory may put the data
5413 somewhere else, so when we send gdb a data base-address, we
5414 use the real data base address and subtract the compile-time
5415 data base-address from it (which is just the length of the
5416 text segment). BSS immediately follows data in both
5419 *data_p
= data
- (text_end
- text
);
5428 linux_qxfer_osdata (const char *annex
,
5429 unsigned char *readbuf
, unsigned const char *writebuf
,
5430 CORE_ADDR offset
, int len
)
5432 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
5435 /* Convert a native/host siginfo object, into/from the siginfo in the
5436 layout of the inferiors' architecture. */
5439 siginfo_fixup (siginfo_t
*siginfo
, void *inf_siginfo
, int direction
)
5443 if (the_low_target
.siginfo_fixup
!= NULL
)
5444 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
5446 /* If there was no callback, or the callback didn't do anything,
5447 then just do a straight memcpy. */
5451 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
5453 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
5458 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
5459 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
5463 char inf_siginfo
[sizeof (siginfo_t
)];
5465 if (current_thread
== NULL
)
5468 pid
= lwpid_of (current_thread
);
5471 debug_printf ("%s siginfo for lwp %d.\n",
5472 readbuf
!= NULL
? "Reading" : "Writing",
5475 if (offset
>= sizeof (siginfo
))
5478 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5481 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
5482 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
5483 inferior with a 64-bit GDBSERVER should look the same as debugging it
5484 with a 32-bit GDBSERVER, we need to convert it. */
5485 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
5487 if (offset
+ len
> sizeof (siginfo
))
5488 len
= sizeof (siginfo
) - offset
;
5490 if (readbuf
!= NULL
)
5491 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
5494 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
5496 /* Convert back to ptrace layout before flushing it out. */
5497 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
5499 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5506 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
5507 so we notice when children change state; as the handler for the
5508 sigsuspend in my_waitpid. */
5511 sigchld_handler (int signo
)
5513 int old_errno
= errno
;
5519 /* fprintf is not async-signal-safe, so call write
5521 if (write (2, "sigchld_handler\n",
5522 sizeof ("sigchld_handler\n") - 1) < 0)
5523 break; /* just ignore */
5527 if (target_is_async_p ())
5528 async_file_mark (); /* trigger a linux_wait */
5534 linux_supports_non_stop (void)
5540 linux_async (int enable
)
5542 int previous
= target_is_async_p ();
5545 debug_printf ("linux_async (%d), previous=%d\n",
5548 if (previous
!= enable
)
5551 sigemptyset (&mask
);
5552 sigaddset (&mask
, SIGCHLD
);
5554 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
5558 if (pipe (linux_event_pipe
) == -1)
5560 linux_event_pipe
[0] = -1;
5561 linux_event_pipe
[1] = -1;
5562 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
5564 warning ("creating event pipe failed.");
5568 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
5569 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
5571 /* Register the event loop handler. */
5572 add_file_handler (linux_event_pipe
[0],
5573 handle_target_event
, NULL
);
5575 /* Always trigger a linux_wait. */
5580 delete_file_handler (linux_event_pipe
[0]);
5582 close (linux_event_pipe
[0]);
5583 close (linux_event_pipe
[1]);
5584 linux_event_pipe
[0] = -1;
5585 linux_event_pipe
[1] = -1;
5588 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
5595 linux_start_non_stop (int nonstop
)
5597 /* Register or unregister from event-loop accordingly. */
5598 linux_async (nonstop
);
5600 if (target_is_async_p () != (nonstop
!= 0))
5607 linux_supports_multi_process (void)
5612 /* Check if fork events are supported. */
5615 linux_supports_fork_events (void)
5617 return linux_supports_tracefork ();
5620 /* Check if vfork events are supported. */
5623 linux_supports_vfork_events (void)
5625 return linux_supports_tracefork ();
5628 /* Callback for 'find_inferior'. Set the (possibly changed) ptrace
5629 options for the specified lwp. */
5632 reset_lwp_ptrace_options_callback (struct inferior_list_entry
*entry
,
5635 struct thread_info
*thread
= (struct thread_info
*) entry
;
5636 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5640 /* Stop the lwp so we can modify its ptrace options. */
5641 lwp
->must_set_ptrace_flags
= 1;
5642 linux_stop_lwp (lwp
);
5646 /* Already stopped; go ahead and set the ptrace options. */
5647 struct process_info
*proc
= find_process_pid (pid_of (thread
));
5648 int options
= linux_low_ptrace_options (proc
->attached
);
5650 linux_enable_event_reporting (lwpid_of (thread
), options
);
5651 lwp
->must_set_ptrace_flags
= 0;
5657 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
5658 ptrace flags for all inferiors. This is in case the new GDB connection
5659 doesn't support the same set of events that the previous one did. */
5662 linux_handle_new_gdb_connection (void)
5666 /* Request that all the lwps reset their ptrace options. */
5667 find_inferior (&all_threads
, reset_lwp_ptrace_options_callback
, &pid
);
5671 linux_supports_disable_randomization (void)
5673 #ifdef HAVE_PERSONALITY
5681 linux_supports_agent (void)
5687 linux_supports_range_stepping (void)
5689 if (*the_low_target
.supports_range_stepping
== NULL
)
5692 return (*the_low_target
.supports_range_stepping
) ();
5695 /* Enumerate spufs IDs for process PID. */
5697 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
5703 struct dirent
*entry
;
5705 sprintf (path
, "/proc/%ld/fd", pid
);
5706 dir
= opendir (path
);
5711 while ((entry
= readdir (dir
)) != NULL
)
5717 fd
= atoi (entry
->d_name
);
5721 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
5722 if (stat (path
, &st
) != 0)
5724 if (!S_ISDIR (st
.st_mode
))
5727 if (statfs (path
, &stfs
) != 0)
5729 if (stfs
.f_type
!= SPUFS_MAGIC
)
5732 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
5734 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
5744 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
5745 object type, using the /proc file system. */
5747 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
5748 unsigned const char *writebuf
,
5749 CORE_ADDR offset
, int len
)
5751 long pid
= lwpid_of (current_thread
);
5756 if (!writebuf
&& !readbuf
)
5764 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
5767 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
5768 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
5773 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5780 ret
= write (fd
, writebuf
, (size_t) len
);
5782 ret
= read (fd
, readbuf
, (size_t) len
);
5788 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
5789 struct target_loadseg
5791 /* Core address to which the segment is mapped. */
5793 /* VMA recorded in the program header. */
5795 /* Size of this segment in memory. */
5799 # if defined PT_GETDSBT
5800 struct target_loadmap
5802 /* Protocol version number, must be zero. */
5804 /* Pointer to the DSBT table, its size, and the DSBT index. */
5805 unsigned *dsbt_table
;
5806 unsigned dsbt_size
, dsbt_index
;
5807 /* Number of segments in this map. */
5809 /* The actual memory map. */
5810 struct target_loadseg segs
[/*nsegs*/];
5812 # define LINUX_LOADMAP PT_GETDSBT
5813 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
5814 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
5816 struct target_loadmap
5818 /* Protocol version number, must be zero. */
5820 /* Number of segments in this map. */
5822 /* The actual memory map. */
5823 struct target_loadseg segs
[/*nsegs*/];
5825 # define LINUX_LOADMAP PTRACE_GETFDPIC
5826 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
5827 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
5831 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
5832 unsigned char *myaddr
, unsigned int len
)
5834 int pid
= lwpid_of (current_thread
);
5836 struct target_loadmap
*data
= NULL
;
5837 unsigned int actual_length
, copy_length
;
5839 if (strcmp (annex
, "exec") == 0)
5840 addr
= (int) LINUX_LOADMAP_EXEC
;
5841 else if (strcmp (annex
, "interp") == 0)
5842 addr
= (int) LINUX_LOADMAP_INTERP
;
5846 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
5852 actual_length
= sizeof (struct target_loadmap
)
5853 + sizeof (struct target_loadseg
) * data
->nsegs
;
5855 if (offset
< 0 || offset
> actual_length
)
5858 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
5859 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
5863 # define linux_read_loadmap NULL
5864 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
5867 linux_process_qsupported (const char *query
)
5869 if (the_low_target
.process_qsupported
!= NULL
)
5870 the_low_target
.process_qsupported (query
);
5874 linux_supports_tracepoints (void)
5876 if (*the_low_target
.supports_tracepoints
== NULL
)
5879 return (*the_low_target
.supports_tracepoints
) ();
5883 linux_read_pc (struct regcache
*regcache
)
5885 if (the_low_target
.get_pc
== NULL
)
5888 return (*the_low_target
.get_pc
) (regcache
);
5892 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
5894 gdb_assert (the_low_target
.set_pc
!= NULL
);
5896 (*the_low_target
.set_pc
) (regcache
, pc
);
5900 linux_thread_stopped (struct thread_info
*thread
)
5902 return get_thread_lwp (thread
)->stopped
;
5905 /* This exposes stop-all-threads functionality to other modules. */
5908 linux_pause_all (int freeze
)
5910 stop_all_lwps (freeze
, NULL
);
5913 /* This exposes unstop-all-threads functionality to other gdbserver
5917 linux_unpause_all (int unfreeze
)
5919 unstop_all_lwps (unfreeze
, NULL
);
5923 linux_prepare_to_access_memory (void)
5925 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5928 linux_pause_all (1);
5933 linux_done_accessing_memory (void)
5935 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5938 linux_unpause_all (1);
5942 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
5943 CORE_ADDR collector
,
5946 CORE_ADDR
*jump_entry
,
5947 CORE_ADDR
*trampoline
,
5948 ULONGEST
*trampoline_size
,
5949 unsigned char *jjump_pad_insn
,
5950 ULONGEST
*jjump_pad_insn_size
,
5951 CORE_ADDR
*adjusted_insn_addr
,
5952 CORE_ADDR
*adjusted_insn_addr_end
,
5955 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
5956 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
5957 jump_entry
, trampoline
, trampoline_size
,
5958 jjump_pad_insn
, jjump_pad_insn_size
,
5959 adjusted_insn_addr
, adjusted_insn_addr_end
,
5963 static struct emit_ops
*
5964 linux_emit_ops (void)
5966 if (the_low_target
.emit_ops
!= NULL
)
5967 return (*the_low_target
.emit_ops
) ();
5973 linux_get_min_fast_tracepoint_insn_len (void)
5975 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
5978 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
5981 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
5982 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
5984 char filename
[PATH_MAX
];
5986 const int auxv_size
= is_elf64
5987 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
5988 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
5990 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5992 fd
= open (filename
, O_RDONLY
);
5998 while (read (fd
, buf
, auxv_size
) == auxv_size
5999 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
6003 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
6005 switch (aux
->a_type
)
6008 *phdr_memaddr
= aux
->a_un
.a_val
;
6011 *num_phdr
= aux
->a_un
.a_val
;
6017 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
6019 switch (aux
->a_type
)
6022 *phdr_memaddr
= aux
->a_un
.a_val
;
6025 *num_phdr
= aux
->a_un
.a_val
;
6033 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
6035 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6036 "phdr_memaddr = %ld, phdr_num = %d",
6037 (long) *phdr_memaddr
, *num_phdr
);
6044 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6047 get_dynamic (const int pid
, const int is_elf64
)
6049 CORE_ADDR phdr_memaddr
, relocation
;
6051 unsigned char *phdr_buf
;
6052 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
6054 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
6057 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
6058 phdr_buf
= alloca (num_phdr
* phdr_size
);
6060 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
6063 /* Compute relocation: it is expected to be 0 for "regular" executables,
6064 non-zero for PIE ones. */
6066 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
6069 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6071 if (p
->p_type
== PT_PHDR
)
6072 relocation
= phdr_memaddr
- p
->p_vaddr
;
6076 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6078 if (p
->p_type
== PT_PHDR
)
6079 relocation
= phdr_memaddr
- p
->p_vaddr
;
6082 if (relocation
== -1)
6084 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6085 any real world executables, including PIE executables, have always
6086 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6087 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6088 or present DT_DEBUG anyway (fpc binaries are statically linked).
6090 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6092 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6097 for (i
= 0; i
< num_phdr
; i
++)
6101 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6103 if (p
->p_type
== PT_DYNAMIC
)
6104 return p
->p_vaddr
+ relocation
;
6108 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6110 if (p
->p_type
== PT_DYNAMIC
)
6111 return p
->p_vaddr
+ relocation
;
6118 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6119 can be 0 if the inferior does not yet have the library list initialized.
6120 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6121 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6124 get_r_debug (const int pid
, const int is_elf64
)
6126 CORE_ADDR dynamic_memaddr
;
6127 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
6128 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
6131 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
6132 if (dynamic_memaddr
== 0)
6135 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
6139 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
6140 #ifdef DT_MIPS_RLD_MAP
6144 unsigned char buf
[sizeof (Elf64_Xword
)];
6148 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6150 if (linux_read_memory (dyn
->d_un
.d_val
,
6151 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6156 #endif /* DT_MIPS_RLD_MAP */
6158 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6159 map
= dyn
->d_un
.d_val
;
6161 if (dyn
->d_tag
== DT_NULL
)
6166 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
6167 #ifdef DT_MIPS_RLD_MAP
6171 unsigned char buf
[sizeof (Elf32_Word
)];
6175 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6177 if (linux_read_memory (dyn
->d_un
.d_val
,
6178 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6183 #endif /* DT_MIPS_RLD_MAP */
6185 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6186 map
= dyn
->d_un
.d_val
;
6188 if (dyn
->d_tag
== DT_NULL
)
6192 dynamic_memaddr
+= dyn_size
;
6198 /* Read one pointer from MEMADDR in the inferior. */
6201 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
6205 /* Go through a union so this works on either big or little endian
6206 hosts, when the inferior's pointer size is smaller than the size
6207 of CORE_ADDR. It is assumed the inferior's endianness is the
6208 same of the superior's. */
6211 CORE_ADDR core_addr
;
6216 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
6219 if (ptr_size
== sizeof (CORE_ADDR
))
6220 *ptr
= addr
.core_addr
;
6221 else if (ptr_size
== sizeof (unsigned int))
6224 gdb_assert_not_reached ("unhandled pointer size");
6229 struct link_map_offsets
6231 /* Offset and size of r_debug.r_version. */
6232 int r_version_offset
;
6234 /* Offset and size of r_debug.r_map. */
6237 /* Offset to l_addr field in struct link_map. */
6240 /* Offset to l_name field in struct link_map. */
6243 /* Offset to l_ld field in struct link_map. */
6246 /* Offset to l_next field in struct link_map. */
6249 /* Offset to l_prev field in struct link_map. */
6253 /* Construct qXfer:libraries-svr4:read reply. */
6256 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
6257 unsigned const char *writebuf
,
6258 CORE_ADDR offset
, int len
)
6261 unsigned document_len
;
6262 struct process_info_private
*const priv
= current_process ()->priv
;
6263 char filename
[PATH_MAX
];
6266 static const struct link_map_offsets lmo_32bit_offsets
=
6268 0, /* r_version offset. */
6269 4, /* r_debug.r_map offset. */
6270 0, /* l_addr offset in link_map. */
6271 4, /* l_name offset in link_map. */
6272 8, /* l_ld offset in link_map. */
6273 12, /* l_next offset in link_map. */
6274 16 /* l_prev offset in link_map. */
6277 static const struct link_map_offsets lmo_64bit_offsets
=
6279 0, /* r_version offset. */
6280 8, /* r_debug.r_map offset. */
6281 0, /* l_addr offset in link_map. */
6282 8, /* l_name offset in link_map. */
6283 16, /* l_ld offset in link_map. */
6284 24, /* l_next offset in link_map. */
6285 32 /* l_prev offset in link_map. */
6287 const struct link_map_offsets
*lmo
;
6288 unsigned int machine
;
6290 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
6291 int allocated
= 1024;
6293 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
6294 int header_done
= 0;
6296 if (writebuf
!= NULL
)
6298 if (readbuf
== NULL
)
6301 pid
= lwpid_of (current_thread
);
6302 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
6303 is_elf64
= elf_64_file_p (filename
, &machine
);
6304 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
6305 ptr_size
= is_elf64
? 8 : 4;
6307 while (annex
[0] != '\0')
6313 sep
= strchr (annex
, '=');
6318 if (len
== 5 && startswith (annex
, "start"))
6320 else if (len
== 4 && startswith (annex
, "prev"))
6324 annex
= strchr (sep
, ';');
6331 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
6338 if (priv
->r_debug
== 0)
6339 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
6341 /* We failed to find DT_DEBUG. Such situation will not change
6342 for this inferior - do not retry it. Report it to GDB as
6343 E01, see for the reasons at the GDB solib-svr4.c side. */
6344 if (priv
->r_debug
== (CORE_ADDR
) -1)
6347 if (priv
->r_debug
!= 0)
6349 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
6350 (unsigned char *) &r_version
,
6351 sizeof (r_version
)) != 0
6354 warning ("unexpected r_debug version %d", r_version
);
6356 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
6357 &lm_addr
, ptr_size
) != 0)
6359 warning ("unable to read r_map from 0x%lx",
6360 (long) priv
->r_debug
+ lmo
->r_map_offset
);
6365 document
= xmalloc (allocated
);
6366 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
6367 p
= document
+ strlen (document
);
6370 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
6371 &l_name
, ptr_size
) == 0
6372 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
6373 &l_addr
, ptr_size
) == 0
6374 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
6375 &l_ld
, ptr_size
) == 0
6376 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
6377 &l_prev
, ptr_size
) == 0
6378 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
6379 &l_next
, ptr_size
) == 0)
6381 unsigned char libname
[PATH_MAX
];
6383 if (lm_prev
!= l_prev
)
6385 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
6386 (long) lm_prev
, (long) l_prev
);
6390 /* Ignore the first entry even if it has valid name as the first entry
6391 corresponds to the main executable. The first entry should not be
6392 skipped if the dynamic loader was loaded late by a static executable
6393 (see solib-svr4.c parameter ignore_first). But in such case the main
6394 executable does not have PT_DYNAMIC present and this function already
6395 exited above due to failed get_r_debug. */
6398 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
6403 /* Not checking for error because reading may stop before
6404 we've got PATH_MAX worth of characters. */
6406 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
6407 libname
[sizeof (libname
) - 1] = '\0';
6408 if (libname
[0] != '\0')
6410 /* 6x the size for xml_escape_text below. */
6411 size_t len
= 6 * strlen ((char *) libname
);
6416 /* Terminate `<library-list-svr4'. */
6421 while (allocated
< p
- document
+ len
+ 200)
6423 /* Expand to guarantee sufficient storage. */
6424 uintptr_t document_len
= p
- document
;
6426 document
= xrealloc (document
, 2 * allocated
);
6428 p
= document
+ document_len
;
6431 name
= xml_escape_text ((char *) libname
);
6432 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
6433 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
6434 name
, (unsigned long) lm_addr
,
6435 (unsigned long) l_addr
, (unsigned long) l_ld
);
6446 /* Empty list; terminate `<library-list-svr4'. */
6450 strcpy (p
, "</library-list-svr4>");
6452 document_len
= strlen (document
);
6453 if (offset
< document_len
)
6454 document_len
-= offset
;
6457 if (len
> document_len
)
6460 memcpy (readbuf
, document
+ offset
, len
);
6466 #ifdef HAVE_LINUX_BTRACE
6468 /* See to_enable_btrace target method. */
6470 static struct btrace_target_info
*
6471 linux_low_enable_btrace (ptid_t ptid
, const struct btrace_config
*conf
)
6473 struct btrace_target_info
*tinfo
;
6475 tinfo
= linux_enable_btrace (ptid
, conf
);
6477 if (tinfo
!= NULL
&& tinfo
->ptr_bits
== 0)
6479 struct thread_info
*thread
= find_thread_ptid (ptid
);
6480 struct regcache
*regcache
= get_thread_regcache (thread
, 0);
6482 tinfo
->ptr_bits
= register_size (regcache
->tdesc
, 0) * 8;
6488 /* See to_disable_btrace target method. */
6491 linux_low_disable_btrace (struct btrace_target_info
*tinfo
)
6493 enum btrace_error err
;
6495 err
= linux_disable_btrace (tinfo
);
6496 return (err
== BTRACE_ERR_NONE
? 0 : -1);
6499 /* Encode an Intel(R) Processor Trace configuration. */
6502 linux_low_encode_pt_config (struct buffer
*buffer
,
6503 const struct btrace_data_pt_config
*config
)
6505 buffer_grow_str (buffer
, "<pt-config>\n");
6507 switch (config
->cpu
.vendor
)
6510 buffer_xml_printf (buffer
, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
6511 "model=\"%u\" stepping=\"%u\"/>\n",
6512 config
->cpu
.family
, config
->cpu
.model
,
6513 config
->cpu
.stepping
);
6520 buffer_grow_str (buffer
, "</pt-config>\n");
6523 /* Encode a raw buffer. */
6526 linux_low_encode_raw (struct buffer
*buffer
, const gdb_byte
*data
,
6532 /* We use hex encoding - see common/rsp-low.h. */
6533 buffer_grow_str (buffer
, "<raw>\n");
6539 elem
[0] = tohex ((*data
>> 4) & 0xf);
6540 elem
[1] = tohex (*data
++ & 0xf);
6542 buffer_grow (buffer
, elem
, 2);
6545 buffer_grow_str (buffer
, "</raw>\n");
6548 /* See to_read_btrace target method. */
6551 linux_low_read_btrace (struct btrace_target_info
*tinfo
, struct buffer
*buffer
,
6554 struct btrace_data btrace
;
6555 struct btrace_block
*block
;
6556 enum btrace_error err
;
6559 btrace_data_init (&btrace
);
6561 err
= linux_read_btrace (&btrace
, tinfo
, type
);
6562 if (err
!= BTRACE_ERR_NONE
)
6564 if (err
== BTRACE_ERR_OVERFLOW
)
6565 buffer_grow_str0 (buffer
, "E.Overflow.");
6567 buffer_grow_str0 (buffer
, "E.Generic Error.");
6572 switch (btrace
.format
)
6574 case BTRACE_FORMAT_NONE
:
6575 buffer_grow_str0 (buffer
, "E.No Trace.");
6578 case BTRACE_FORMAT_BTS
:
6579 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
6580 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
6583 VEC_iterate (btrace_block_s
, btrace
.variant
.bts
.blocks
, i
, block
);
6585 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
6586 paddress (block
->begin
), paddress (block
->end
));
6588 buffer_grow_str0 (buffer
, "</btrace>\n");
6591 case BTRACE_FORMAT_PT
:
6592 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
6593 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
6594 buffer_grow_str (buffer
, "<pt>\n");
6596 linux_low_encode_pt_config (buffer
, &btrace
.variant
.pt
.config
);
6598 linux_low_encode_raw (buffer
, btrace
.variant
.pt
.data
,
6599 btrace
.variant
.pt
.size
);
6601 buffer_grow_str (buffer
, "</pt>\n");
6602 buffer_grow_str0 (buffer
, "</btrace>\n");
6606 buffer_grow_str0 (buffer
, "E.Unsupported Trace Format.");
6610 btrace_data_fini (&btrace
);
6614 btrace_data_fini (&btrace
);
6618 /* See to_btrace_conf target method. */
6621 linux_low_btrace_conf (const struct btrace_target_info
*tinfo
,
6622 struct buffer
*buffer
)
6624 const struct btrace_config
*conf
;
6626 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
6627 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
6629 conf
= linux_btrace_conf (tinfo
);
6632 switch (conf
->format
)
6634 case BTRACE_FORMAT_NONE
:
6637 case BTRACE_FORMAT_BTS
:
6638 buffer_xml_printf (buffer
, "<bts");
6639 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
6640 buffer_xml_printf (buffer
, " />\n");
6643 case BTRACE_FORMAT_PT
:
6644 buffer_xml_printf (buffer
, "<pt");
6645 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->pt
.size
);
6646 buffer_xml_printf (buffer
, "/>\n");
6651 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
6654 #endif /* HAVE_LINUX_BTRACE */
6656 /* See nat/linux-nat.h. */
6659 current_lwp_ptid (void)
6661 return ptid_of (current_thread
);
6664 static struct target_ops linux_target_ops
= {
6665 linux_create_inferior
,
6675 linux_fetch_registers
,
6676 linux_store_registers
,
6677 linux_prepare_to_access_memory
,
6678 linux_done_accessing_memory
,
6681 linux_look_up_symbols
,
6682 linux_request_interrupt
,
6684 linux_supports_z_point_type
,
6687 linux_stopped_by_sw_breakpoint
,
6688 linux_supports_stopped_by_sw_breakpoint
,
6689 linux_stopped_by_hw_breakpoint
,
6690 linux_supports_stopped_by_hw_breakpoint
,
6691 linux_supports_conditional_breakpoints
,
6692 linux_stopped_by_watchpoint
,
6693 linux_stopped_data_address
,
6694 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
6695 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
6696 && defined(PT_TEXT_END_ADDR)
6701 #ifdef USE_THREAD_DB
6702 thread_db_get_tls_address
,
6707 hostio_last_error_from_errno
,
6710 linux_supports_non_stop
,
6712 linux_start_non_stop
,
6713 linux_supports_multi_process
,
6714 linux_supports_fork_events
,
6715 linux_supports_vfork_events
,
6716 linux_handle_new_gdb_connection
,
6717 #ifdef USE_THREAD_DB
6718 thread_db_handle_monitor_command
,
6722 linux_common_core_of_thread
,
6724 linux_process_qsupported
,
6725 linux_supports_tracepoints
,
6728 linux_thread_stopped
,
6732 linux_stabilize_threads
,
6733 linux_install_fast_tracepoint_jump_pad
,
6735 linux_supports_disable_randomization
,
6736 linux_get_min_fast_tracepoint_insn_len
,
6737 linux_qxfer_libraries_svr4
,
6738 linux_supports_agent
,
6739 #ifdef HAVE_LINUX_BTRACE
6740 linux_supports_btrace
,
6741 linux_low_enable_btrace
,
6742 linux_low_disable_btrace
,
6743 linux_low_read_btrace
,
6744 linux_low_btrace_conf
,
6752 linux_supports_range_stepping
,
6753 linux_proc_pid_to_exec_file
,
6754 linux_mntns_open_cloexec
,
6756 linux_mntns_readlink
,
6760 linux_init_signals ()
6762 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
6763 to find what the cancel signal actually is. */
6764 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
6765 signal (__SIGRTMIN
+1, SIG_IGN
);
6769 #ifdef HAVE_LINUX_REGSETS
6771 initialize_regsets_info (struct regsets_info
*info
)
6773 for (info
->num_regsets
= 0;
6774 info
->regsets
[info
->num_regsets
].size
>= 0;
6775 info
->num_regsets
++)
6781 initialize_low (void)
6783 struct sigaction sigchld_action
;
6784 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
6785 set_target_ops (&linux_target_ops
);
6786 set_breakpoint_data (the_low_target
.breakpoint
,
6787 the_low_target
.breakpoint_len
);
6788 linux_init_signals ();
6789 linux_ptrace_init_warnings ();
6791 sigchld_action
.sa_handler
= sigchld_handler
;
6792 sigemptyset (&sigchld_action
.sa_mask
);
6793 sigchld_action
.sa_flags
= SA_RESTART
;
6794 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
6796 initialize_low_arch ();
6798 linux_check_ptrace_features ();