/* Memory breakpoint operations for the remote server for GDB.
- Copyright (C) 2002, 2003, 2005, 2007, 2008, 2009, 2010
+ Copyright (C) 2002, 2003, 2005, 2007, 2008, 2009, 2010, 2011
Free Software Foundation, Inc.
Contributed by MontaVista Software.
bp->pc = where;
bp->refcount = 1;
- err = (*the_target->read_memory) (where, bp->old_data,
- breakpoint_len);
+ /* Note that there can be fast tracepoint jumps installed in the
+ same memory range, so to get at the original memory, we need to
+ use read_inferior_memory, which masks those out. */
+ err = read_inferior_memory (where, bp->old_data, breakpoint_len);
if (err != 0)
{
if (debug_threads)
return bp;
}
+/* Notice that breakpoint traps are always installed on top of fast
+ tracepoint jumps. This is even if the fast tracepoint is installed
+ at a later time compared to when the breakpoint was installed.
+ This means that a stopping breakpoint or tracepoint has higher
+ "priority". In turn, this allows having fast and slow tracepoints
+ (and breakpoints) at the same address behave correctly. */
+
+
+/* A fast tracepoint jump. */
+
+struct fast_tracepoint_jump
+{
+ struct fast_tracepoint_jump *next;
+
+ /* A reference count. GDB can install more than one fast tracepoint
+ at the same address (each with its own action list, for
+ example). */
+ int refcount;
+
+ /* The fast tracepoint's insertion address. There can only be one
+ of these for a given PC. */
+ CORE_ADDR pc;
+
+ /* Non-zero if this fast tracepoint jump is currently inserted in
+ the inferior. */
+ int inserted;
+
+ /* The length of the jump instruction. */
+ int length;
+
+ /* A poor-man's flexible array member, holding both the jump
+ instruction to insert, and a copy of the instruction that would
+ be in memory had not been a jump there (the shadow memory of the
+ tracepoint jump). */
+ unsigned char insn_and_shadow[0];
+};
+
+/* Fast tracepoint FP's jump instruction to insert. */
+#define fast_tracepoint_jump_insn(fp) \
+ ((fp)->insn_and_shadow + 0)
+
+/* The shadow memory of fast tracepoint jump FP. */
+#define fast_tracepoint_jump_shadow(fp) \
+ ((fp)->insn_and_shadow + (fp)->length)
+
+
+/* Return the fast tracepoint jump set at WHERE. */
+
+static struct fast_tracepoint_jump *
+find_fast_tracepoint_jump_at (CORE_ADDR where)
+{
+ struct process_info *proc = current_process ();
+ struct fast_tracepoint_jump *jp;
+
+ for (jp = proc->fast_tracepoint_jumps; jp != NULL; jp = jp->next)
+ if (jp->pc == where)
+ return jp;
+
+ return NULL;
+}
+
+int
+fast_tracepoint_jump_here (CORE_ADDR where)
+{
+ struct fast_tracepoint_jump *jp = find_fast_tracepoint_jump_at (where);
+
+ return (jp != NULL);
+}
+
+int
+delete_fast_tracepoint_jump (struct fast_tracepoint_jump *todel)
+{
+ struct fast_tracepoint_jump *bp, **bp_link;
+ int ret;
+ struct process_info *proc = current_process ();
+
+ bp = proc->fast_tracepoint_jumps;
+ bp_link = &proc->fast_tracepoint_jumps;
+
+ while (bp)
+ {
+ if (bp == todel)
+ {
+ if (--bp->refcount == 0)
+ {
+ struct fast_tracepoint_jump *prev_bp_link = *bp_link;
+
+ /* Unlink it. */
+ *bp_link = bp->next;
+
+ /* Since there can be breakpoints inserted in the same
+ address range, we use `write_inferior_memory', which
+ takes care of layering breakpoints on top of fast
+ tracepoints, and on top of the buffer we pass it.
+ This works because we've already unlinked the fast
+ tracepoint jump above. Also note that we need to
+ pass the current shadow contents, because
+ write_inferior_memory updates any shadow memory with
+ what we pass here, and we want that to be a nop. */
+ ret = write_inferior_memory (bp->pc,
+ fast_tracepoint_jump_shadow (bp),
+ bp->length);
+ if (ret != 0)
+ {
+ /* Something went wrong, relink the jump. */
+ *bp_link = prev_bp_link;
+
+ if (debug_threads)
+ fprintf (stderr,
+ "Failed to uninsert fast tracepoint jump "
+ "at 0x%s (%s) while deleting it.\n",
+ paddress (bp->pc), strerror (ret));
+ return ret;
+ }
+
+ free (bp);
+ }
+
+ return 0;
+ }
+ else
+ {
+ bp_link = &bp->next;
+ bp = *bp_link;
+ }
+ }
+
+ warning ("Could not find fast tracepoint jump in list.");
+ return ENOENT;
+}
+
+struct fast_tracepoint_jump *
+set_fast_tracepoint_jump (CORE_ADDR where,
+ unsigned char *insn, ULONGEST length)
+{
+ struct process_info *proc = current_process ();
+ struct fast_tracepoint_jump *jp;
+ int err;
+
+ /* We refcount fast tracepoint jumps. Check if we already know
+ about a jump at this address. */
+ jp = find_fast_tracepoint_jump_at (where);
+ if (jp != NULL)
+ {
+ jp->refcount++;
+ return jp;
+ }
+
+ /* We don't, so create a new object. Double the length, because the
+ flexible array member holds both the jump insn, and the
+ shadow. */
+ jp = xcalloc (1, sizeof (*jp) + (length * 2));
+ jp->pc = where;
+ jp->length = length;
+ memcpy (fast_tracepoint_jump_insn (jp), insn, length);
+ jp->refcount = 1;
+
+ /* Note that there can be trap breakpoints inserted in the same
+ address range. To access the original memory contents, we use
+ `read_inferior_memory', which masks out breakpoints. */
+ err = read_inferior_memory (where,
+ fast_tracepoint_jump_shadow (jp), jp->length);
+ if (err != 0)
+ {
+ if (debug_threads)
+ fprintf (stderr,
+ "Failed to read shadow memory of"
+ " fast tracepoint at 0x%s (%s).\n",
+ paddress (where), strerror (err));
+ free (jp);
+ return NULL;
+ }
+
+ /* Link the jump in. */
+ jp->inserted = 1;
+ jp->next = proc->fast_tracepoint_jumps;
+ proc->fast_tracepoint_jumps = jp;
+
+ /* Since there can be trap breakpoints inserted in the same address
+ range, we use use `write_inferior_memory', which takes care of
+ layering breakpoints on top of fast tracepoints, on top of the
+ buffer we pass it. This works because we've already linked in
+ the fast tracepoint jump above. Also note that we need to pass
+ the current shadow contents, because write_inferior_memory
+ updates any shadow memory with what we pass here, and we want
+ that to be a nop. */
+ err = write_inferior_memory (where, fast_tracepoint_jump_shadow (jp),
+ length);
+ if (err != 0)
+ {
+ if (debug_threads)
+ fprintf (stderr,
+ "Failed to insert fast tracepoint jump at 0x%s (%s).\n",
+ paddress (where), strerror (err));
+
+ /* Unlink it. */
+ proc->fast_tracepoint_jumps = jp->next;
+ free (jp);
+
+ return NULL;
+ }
+
+ return jp;
+}
+
+void
+uninsert_fast_tracepoint_jumps_at (CORE_ADDR pc)
+{
+ struct fast_tracepoint_jump *jp;
+ int err;
+
+ jp = find_fast_tracepoint_jump_at (pc);
+ if (jp == NULL)
+ {
+ /* This can happen when we remove all breakpoints while handling
+ a step-over. */
+ if (debug_threads)
+ fprintf (stderr,
+ "Could not find fast tracepoint jump at 0x%s "
+ "in list (uninserting).\n",
+ paddress (pc));
+ return;
+ }
+
+ if (jp->inserted)
+ {
+ jp->inserted = 0;
+
+ /* Since there can be trap breakpoints inserted in the same
+ address range, we use use `write_inferior_memory', which
+ takes care of layering breakpoints on top of fast
+ tracepoints, and on top of the buffer we pass it. This works
+ because we've already marked the fast tracepoint fast
+ tracepoint jump uninserted above. Also note that we need to
+ pass the current shadow contents, because
+ write_inferior_memory updates any shadow memory with what we
+ pass here, and we want that to be a nop. */
+ err = write_inferior_memory (jp->pc,
+ fast_tracepoint_jump_shadow (jp),
+ jp->length);
+ if (err != 0)
+ {
+ jp->inserted = 1;
+
+ if (debug_threads)
+ fprintf (stderr,
+ "Failed to uninsert fast tracepoint jump at 0x%s (%s).\n",
+ paddress (pc), strerror (err));
+ }
+ }
+}
+
+void
+reinsert_fast_tracepoint_jumps_at (CORE_ADDR where)
+{
+ struct fast_tracepoint_jump *jp;
+ int err;
+
+ jp = find_fast_tracepoint_jump_at (where);
+ if (jp == NULL)
+ {
+ /* This can happen when we remove breakpoints when a tracepoint
+ hit causes a tracing stop, while handling a step-over. */
+ if (debug_threads)
+ fprintf (stderr,
+ "Could not find fast tracepoint jump at 0x%s "
+ "in list (reinserting).\n",
+ paddress (where));
+ return;
+ }
+
+ if (jp->inserted)
+ error ("Jump already inserted at reinsert time.");
+
+ jp->inserted = 1;
+
+ /* Since there can be trap breakpoints inserted in the same address
+ range, we use `write_inferior_memory', which takes care of
+ layering breakpoints on top of fast tracepoints, and on top of
+ the buffer we pass it. This works because we've already marked
+ the fast tracepoint jump inserted above. Also note that we need
+ to pass the current shadow contents, because
+ write_inferior_memory updates any shadow memory with what we pass
+ here, and we want that to be a nop. */
+ err = write_inferior_memory (where,
+ fast_tracepoint_jump_shadow (jp), jp->length);
+ if (err != 0)
+ {
+ jp->inserted = 0;
+
+ if (debug_threads)
+ fprintf (stderr,
+ "Failed to reinsert fast tracepoint jump at 0x%s (%s).\n",
+ paddress (where), strerror (err));
+ }
+}
+
struct breakpoint *
set_breakpoint_at (CORE_ADDR where, int (*handler) (CORE_ADDR))
{
*bp_link = bp->next;
- ret = (*the_target->write_memory) (bp->pc, bp->old_data,
- breakpoint_len);
+ /* Since there can be trap breakpoints inserted in the
+ same address range, we use `write_inferior_memory',
+ which takes care of layering breakpoints on top of
+ fast tracepoints, and on top of the buffer we pass
+ it. This works because we've already unlinked the
+ fast tracepoint jump above. Also note that we need
+ to pass the current shadow contents, because
+ write_inferior_memory updates any shadow memory with
+ what we pass here, and we want that to be a nop. */
+ ret = write_inferior_memory (bp->pc, bp->old_data,
+ breakpoint_len);
if (ret != 0)
{
/* Something went wrong, relink the breakpoint. */
int err;
bp->inserted = 0;
- err = (*the_target->write_memory) (bp->pc, bp->old_data,
- breakpoint_len);
+ /* Since there can be fast tracepoint jumps inserted in the same
+ address range, we use `write_inferior_memory', which takes
+ care of layering breakpoints on top of fast tracepoints, and
+ on top of the buffer we pass it. This works because we've
+ already unlinked the fast tracepoint jump above. Also note
+ that we need to pass the current shadow contents, because
+ write_inferior_memory updates any shadow memory with what we
+ pass here, and we want that to be a nop. */
+ err = write_inferior_memory (bp->pc, bp->old_data,
+ breakpoint_len);
if (err != 0)
{
bp->inserted = 1;
uninsert_raw_breakpoint (bp);
}
+void
+uninsert_all_breakpoints (void)
+{
+ struct process_info *proc = current_process ();
+ struct raw_breakpoint *bp;
+
+ for (bp = proc->raw_breakpoints; bp != NULL; bp = bp->next)
+ if (bp->inserted)
+ uninsert_raw_breakpoint (bp);
+}
+
static void
reinsert_raw_breakpoint (struct raw_breakpoint *bp)
{
reinsert_raw_breakpoint (bp);
}
+void
+reinsert_all_breakpoints (void)
+{
+ struct process_info *proc = current_process ();
+ struct raw_breakpoint *bp;
+
+ for (bp = proc->raw_breakpoints; bp != NULL; bp = bp->next)
+ if (!bp->inserted)
+ reinsert_raw_breakpoint (bp);
+}
+
void
check_breakpoints (CORE_ADDR stop_pc)
{
{
struct process_info *proc = current_process ();
struct raw_breakpoint *bp = proc->raw_breakpoints;
+ struct fast_tracepoint_jump *jp = proc->fast_tracepoint_jumps;
CORE_ADDR mem_end = mem_addr + mem_len;
int disabled_one = 0;
+ for (; jp != NULL; jp = jp->next)
+ {
+ CORE_ADDR bp_end = jp->pc + jp->length;
+ CORE_ADDR start, end;
+ int copy_offset, copy_len, buf_offset;
+
+ if (mem_addr >= bp_end)
+ continue;
+ if (jp->pc >= mem_end)
+ continue;
+
+ start = jp->pc;
+ if (mem_addr > start)
+ start = mem_addr;
+
+ end = bp_end;
+ if (end > mem_end)
+ end = mem_end;
+
+ copy_len = end - start;
+ copy_offset = start - jp->pc;
+ buf_offset = start - mem_addr;
+
+ if (jp->inserted)
+ memcpy (buf + buf_offset,
+ fast_tracepoint_jump_shadow (jp) + copy_offset,
+ copy_len);
+ }
+
for (; bp != NULL; bp = bp->next)
{
CORE_ADDR bp_end = bp->pc + breakpoint_len;
{
struct process_info *proc = current_process ();
struct raw_breakpoint *bp = proc->raw_breakpoints;
+ struct fast_tracepoint_jump *jp = proc->fast_tracepoint_jumps;
CORE_ADDR mem_end = mem_addr + mem_len;
int disabled_one = 0;
+ /* First fast tracepoint jumps, then breakpoint traps on top. */
+
+ for (; jp != NULL; jp = jp->next)
+ {
+ CORE_ADDR jp_end = jp->pc + jp->length;
+ CORE_ADDR start, end;
+ int copy_offset, copy_len, buf_offset;
+
+ if (mem_addr >= jp_end)
+ continue;
+ if (jp->pc >= mem_end)
+ continue;
+
+ start = jp->pc;
+ if (mem_addr > start)
+ start = mem_addr;
+
+ end = jp_end;
+ if (end > mem_end)
+ end = mem_end;
+
+ copy_len = end - start;
+ copy_offset = start - jp->pc;
+ buf_offset = start - mem_addr;
+
+ memcpy (fast_tracepoint_jump_shadow (jp) + copy_offset,
+ buf + buf_offset, copy_len);
+ if (jp->inserted)
+ memcpy (buf + buf_offset,
+ fast_tracepoint_jump_insn (jp) + copy_offset, copy_len);
+ }
+
for (; bp != NULL; bp = bp->next)
{
CORE_ADDR bp_end = bp->pc + breakpoint_len;
delete_breakpoint_1 (proc, proc->breakpoints);
}
-/* Release all breakpoints, but do not try to un-insert them from the
- inferior. */
+/* Clear the "inserted" flag in all breakpoints. */
void
-free_all_breakpoints (struct process_info *proc)
+mark_breakpoints_out (struct process_info *proc)
{
struct raw_breakpoint *raw_bp;
for (raw_bp = proc->raw_breakpoints; raw_bp != NULL; raw_bp = raw_bp->next)
raw_bp->inserted = 0;
+}
+
+/* Release all breakpoints, but do not try to un-insert them from the
+ inferior. */
+
+void
+free_all_breakpoints (struct process_info *proc)
+{
+ mark_breakpoints_out (proc);
/* Note: use PROC explicitly instead of deferring to
delete_all_breakpoints --- CURRENT_INFERIOR may already have been
projects / deliverable / binutils-gdb.git / blobdiff