[testsuite] Unbuffer the output in gdb.base/multi-forks.c

[deliverable/binutils-gdb.git] / gdb / linux-thread-db.c

diff --git a/gdb/linux-thread-db.c b/gdb/linux-thread-db.c
index 8a80ca3168bcd9d4f79013f897708f06d2e2fab9..1eb457de105823df829f6013ff3d01d5932fe938 100644 (file)
--- a/gdb/linux-thread-db.c
+++ b/gdb/linux-thread-db.c
@@ -1,6 +1,6 @@
 /* libthread_db assisted debugging support, generic parts.
 
-   Copyright (C) 1999-2015 Free Software Foundation, Inc.
+   Copyright (C) 1999-2016 Free Software Foundation, Inc.
 
    This file is part of GDB.
 
@@ -54,11 +54,12 @@
    created, thread IDs (usually, the result of pthread_self), and
    thread-local variables.
 
-   The libthread_db interface originates on Solaris, where it is
-   both more powerful and more complicated.  This implementation
-   only works for LinuxThreads and NPTL, the two glibc threading
-   libraries.  It assumes that each thread is permanently assigned
-   to a single light-weight process (LWP).
+   The libthread_db interface originates on Solaris, where it is both
+   more powerful and more complicated.  This implementation only works
+   for NPTL, the glibc threading library.  It assumes that each thread
+   is permanently assigned to a single light-weight process (LWP).  At
+   some point it also supported the older LinuxThreads library, but it
+   no longer does.
 
    libthread_db-specific information is stored in the "private" field
    of struct thread_info.  When the field is NULL we do not yet have
@@ -1226,7 +1227,7 @@ find_new_threads_callback (const td_thrhandle_t *th_p, void *data)
   ptid = ptid_build (info->pid, ti.ti_lid, 0);
   tp = find_thread_ptid (ptid);
   if (tp == NULL || tp->priv == NULL)
-    thread_from_lwp (ptid);
+    record_thread (info, tp, ptid, th_p, &ti);
 
   return 0;
 }
@@ -1323,17 +1324,11 @@ thread_db_find_new_threads_1 (ptid_t ptid)
   thread_db_find_new_threads_2 (ptid, 0);
 }
 
-static int
-update_thread_core (struct lwp_info *info, void *closure)
-{
-  info->core = linux_common_core_of_thread (info->ptid);
-  return 0;
-}
-
-/* Update the thread list using td_ta_thr_iter.  */
+/* Implement the to_update_thread_list target method for this
+   target.  */
 
 static void
-thread_db_update_thread_list_td_ta_thr_iter (struct target_ops *ops)
+thread_db_update_thread_list (struct target_ops *ops)
 {
   struct thread_db_info *info;
   struct inferior *inf;
@@ -1355,34 +1350,25 @@ thread_db_update_thread_list_td_ta_thr_iter (struct target_ops *ops)
       if (thread == NULL || thread->executing)
        continue;
 
+      /* It's best to avoid td_ta_thr_iter if possible.  That walks
+        data structures in the inferior's address space that may be
+        corrupted, or, if the target is running, the list may change
+        while we walk it.  In the latter case, it's possible that a
+        thread exits just at the exact time that causes GDB to get
+        stuck in an infinite loop.  To avoid pausing all threads
+        whenever the core wants to refresh the thread list, we
+        instead use thread_from_lwp immediately when we see an LWP
+        stop.  That uses thread_db entry points that do not walk
+        libpthread's thread list, so should be safe, as well as more
+        efficient.  */
+      if (target_has_execution_1 (thread->ptid))
+       continue;
+
       thread_db_find_new_threads_1 (thread->ptid);
     }
-}
 
-/* Implement the to_update_thread_list target method for this
-   target.  */
-
-static void
-thread_db_update_thread_list (struct target_ops *ops)
-{
-  /* It's best to avoid td_ta_thr_iter if possible.  That walks data
-     structures in the inferior's address space that may be corrupted,
-     or, if the target is running, the list may change while we walk
-     it.  In the latter case, it's possible that a thread exits just
-     at the exact time that causes GDB to get stuck in an infinite
-     loop.  To avoid pausing all threads whenever the core wants to
-     refresh the thread list, use thread_from_lwp immediately when we
-     see an LWP stop.  That uses  thread_db entry points that do not
-     walk libpthread's thread list, so should be safe, as well as
-     more efficient.  */
-  if (target_has_execution)
-    ops->beneath->to_update_thread_list (ops->beneath);
-  else
-    thread_db_update_thread_list_td_ta_thr_iter (ops);
-
-  if (target_has_execution)
-    iterate_over_lwps (minus_one_ptid /* iterate over all */,
-                      update_thread_core, NULL);
+  /* Give the beneath target a chance to do extra processing.  */
+  ops->beneath->to_update_thread_list (ops->beneath);
 }
 
 static char *
@@ -1717,10 +1703,9 @@ _initialize_thread_db (void)
 
   /* Defer loading of libthread_db.so until inferior is running.
      This allows gdb to load correct libthread_db for a given
-     executable -- there could be mutiple versions of glibc,
-     compiled with LinuxThreads or NPTL, and until there is
-     a running inferior, we can't tell which libthread_db is
-     the correct one to load.  */
+     executable -- there could be multiple versions of glibc,
+     and until there is a running inferior, we can't tell which
+     libthread_db is the correct one to load.  */
 
   libthread_db_search_path = xstrdup (LIBTHREAD_DB_SEARCH_PATH);