A patch I wrote made GDB pull the thread list sooner when debugging
with target remote, and I noticed an intended consequence. GDB
started bouncing around the currently selected remote/general thread
more frequently. E.g.:
Sending packet: $qTMinFTPILen#3b...Packet received: 5
+Sending packet: $Hgp726d.726d#53...Packet received: OK
Sending packet: $m400680,40#2f...Packet received: 85c0741455bff00d60004889e5ffd05de97bffffff0f1f00e973ffffff0f1f00554889e5c745fc00000000c745fc01000000e900000000c745fc02000000b800
+Sending packet: $Hgp726d.7278#28...Packet received: OK
Sending packet: $m4006b2,1#28...Packet received: e9
Fast tracepoint 2 at 0x4006b2: file gdb/testsuite/gdb.trace/range-stepping.c, line 53.
Sending packet: $qTStatus#49...Packet received: T0;tnotrun:0;tframes:0;tcreated:0;tfree:500000;tsize:500000;circular:0;disconn:0;starttime:0;stoptime:0;username:;notes::
This ended up breaking "tstart" when one has fast tracepoints set,
because gdbserver isn't expecting an Hg packet in response to
qRelocInsn:
(gdb) ftrace *set_point
Fast tracepoint 3 at 0x4006b2: file gdb/testsuite/gdb.trace/range-stepping.c, line 53.
(gdb) PASS: gdb.trace/range-stepping.exp: ftrace: ftrace *set_point
tstart
gdbserver: Malformed response to qRelocInsn, ignoring: Hgp2783.2783
Target does not support this command.
(gdb) FAIL: gdb.trace/range-stepping.exp: ftrace: tstart
remote_trace_start should probably start by making sure the remote
current thread matches inferior_ptid (calling set_general_thread), but
still, reducing unnecessary bouncing is a good idea. It happens
because the memory/symbol/breakpoint routines use
switch_to_program_space_and_thread to do something in the right
context and then revert back to the previously current thread.
The fix is to simply make any_thread_of_process,
find_inferior_for_program_space, etc. give preference to the current
thread/inferior it if matches.
gdb/
2014-10-02 Pedro Alves <palves@redhat.com>
* gdbthread.h (any_thread_of_process, any_live_thread_of_process):
Adjust comments.
* inferior.c (find_inferior_for_program_space): Give preference to
the current inferior.
* inferior.h (find_inferior_for_program_space): Update comment.
* progspace.c (switch_to_program_space_and_thread): Prefer the
current inferior if it's bound to the program space requested. If
the inferior found doesn't have a PID yet, don't bother looking up
a thread.
* progspace.h (switch_to_program_space_and_thread): Adjust
comment.
* thread.c (any_thread_of_process, any_live_thread_of_process):
Give preference to the current thread.
+2014-10-02 Pedro Alves <palves@redhat.com>
+
+ * gdbthread.h (any_thread_of_process, any_live_thread_of_process):
+ Adjust comments.
+ * inferior.c (find_inferior_for_program_space): Give preference to
+ the current inferior.
+ * inferior.h (find_inferior_for_program_space): Update comment.
+ * progspace.c (switch_to_program_space_and_thread): Prefer the
+ current inferior if it's bound to the program space requested. If
+ the inferior found doesn't have a PID yet, don't bother looking up
+ a thread.
+ * progspace.h (switch_to_program_space_and_thread): Adjust
+ comment.
+ * thread.c (any_thread_of_process, any_live_thread_of_process):
+ Give preference to the current thread.
+
2014-10-01 Pedro Alves <palves@redhat.com>
* breakpoint.c (insert_bp_location): Error out if inserting a
returns the first thread in the list. */
struct thread_info *first_thread_of_process (int pid);
-/* Returns any thread of process PID. */
+/* Returns any thread of process PID, giving preference to the current
+ thread. */
extern struct thread_info *any_thread_of_process (int pid);
-/* Returns any non-exited thread of process PID, giving preference for
- not executing threads. */
+/* Returns any non-exited thread of process PID, giving preference to
+ the current thread, and to not executing threads. */
extern struct thread_info *any_live_thread_of_process (int pid);
/* Change the ptid of thread OLD_PTID to NEW_PTID. */
return NULL;
}
-/* Find an inferior bound to PSPACE. */
+/* See inferior.h. */
struct inferior *
find_inferior_for_program_space (struct program_space *pspace)
{
- struct inferior *inf;
+ struct inferior *inf = current_inferior ();
+
+ if (inf->pspace == pspace)
+ return inf;
for (inf = inferior_list; inf != NULL; inf = inf->next)
{
/* Search function to lookup an inferior by GDB 'num'. */
extern struct inferior *find_inferior_id (int num);
-/* Find an inferior bound to PSPACE. */
+/* Find an inferior bound to PSPACE, giving preference to the current
+ inferior. */
extern struct inferior *
find_inferior_for_program_space (struct program_space *pspace);
return old_chain;
}
-/* Switches full context to program space PSPACE. Switches to the
- first thread found bound to PSPACE. */
+/* See progspace.h */
void
switch_to_program_space_and_thread (struct program_space *pspace)
struct inferior *inf;
inf = find_inferior_for_program_space (pspace);
- if (inf != NULL)
+ if (inf != NULL && inf->pid != 0)
{
struct thread_info *tp;
extern struct cleanup *save_current_space_and_thread (void);
/* Switches full context to program space PSPACE. Switches to the
- first thread found bound to PSPACE. */
+ first thread found bound to PSPACE, giving preference to the
+ current thread, if there's one and it isn't executing. */
extern void switch_to_program_space_and_thread (struct program_space *pspace);
/* Create a new address space object, and add it to the list. */
{
struct thread_info *tp;
- for (tp = thread_list; tp; tp = tp->next)
+ gdb_assert (pid != 0);
+
+ /* Prefer the current thread. */
+ if (ptid_get_pid (inferior_ptid) == pid)
+ return inferior_thread ();
+
+ ALL_NON_EXITED_THREADS (tp)
if (ptid_get_pid (tp->ptid) == pid)
return tp;
struct thread_info *
any_live_thread_of_process (int pid)
{
+ struct thread_info *curr_tp = NULL;
struct thread_info *tp;
struct thread_info *tp_executing = NULL;
- for (tp = thread_list; tp; tp = tp->next)
- if (tp->state != THREAD_EXITED && ptid_get_pid (tp->ptid) == pid)
+ gdb_assert (pid != 0);
+
+ /* Prefer the current thread if it's not executing. */
+ if (ptid_get_pid (inferior_ptid) == pid)
+ {
+ /* If the current thread is dead, forget it. If it's not
+ executing, use it. Otherwise, still choose it (below), but
+ only if no other non-executing thread is found. */
+ curr_tp = inferior_thread ();
+ if (curr_tp->state == THREAD_EXITED)
+ curr_tp = NULL;
+ else if (!curr_tp->executing)
+ return curr_tp;
+ }
+
+ ALL_NON_EXITED_THREADS (tp)
+ if (ptid_get_pid (tp->ptid) == pid)
{
- if (tp->executing)
- tp_executing = tp;
- else
+ if (!tp->executing)
return tp;
+
+ tp_executing = tp;
}
+ /* If both the current thread and all live threads are executing,
+ prefer the current thread. */
+ if (curr_tp != NULL)
+ return curr_tp;
+
+ /* Otherwise, just return an executing thread, if any. */
return tp_executing;
}
projects / thirdparty / binutils-gdb.git / commitdiff
