Pedro Alves 65706a29ba Remote thread create/exit events ... When testing with "maint set target-non-stop on", a few threading-related tests expose an issue that requires new RSP packets. Say there are 3 threads running, 1-3. If GDB tries to stop thread 1, 2 and 3, and then waits for their stops, but meanwhile say, thread 2 exits, GDB hangs forever waiting for a stop for thread 2 that won't ever happen. This patch fixes the issue by adding support for thread exit events to the protocol. However, we don't want these always enabled, as they're useless most of the time, and would slow down remote debugging. So I made it so that GDB can enable/disable them, and then made gdb do that around the cases that need it, which currently is only infrun.c:stop_all_threads. In turn, if we have thread exit events, then the extra "thread x exited" traffic slows down attach-many-short-lived-threads.exp enough that gdb has trouble keeping up with new threads that are spawned while gdb tries to stop existing ones. To fix that I added support for the counterpart thread created events too. Enabling those when we try to stop threads ensures that new threads never get a chance to themselves start new threads, killing the race. gdb/doc/ChangeLog: 2015-11-30 Pedro Alves <palves@redhat.com> * gdb.texinfo (Remote Configuration): List "set/show remote thread-events" command in configuration table. (Stop Reply Packets): Document "T05 create" stop reason and 'w' stop reply. (General Query Packets): Document QThreadEvents packet. Document QThreadEvents qSupported feature. gdb/gdbserver/ChangeLog: 2015-11-30 Pedro Alves <palves@redhat.com> * linux-low.c (handle_extended_wait): Assert that the LWP's waitstatus is TARGET_WAITKIND_IGNORE. If GDB wants to hear about thread create events, leave the new child's status pending. (linux_low_filter_event): If GDB wants to hear about thread exit events, leave the LWP marked dead and don't delete it. (linux_wait_for_event_filtered): Don't check for thread exit. (filter_exit_event): New function. (linux_wait_1): Use it, when returning an exit event. (linux_resume_one_lwp_throw): Assert that the LWP's waitstatus is TARGET_WAITKIND_IGNORE. * remote-utils.c (prepare_resume_reply): Handle TARGET_WAITKIND_THREAD_CREATED and TARGET_WAITKIND_THREAD_EXITED. * server.c (report_thread_events): New global. (handle_general_set): Handle QThreadEvents. (handle_query) <qSupported>: Handle and report QThreadEvents+; (handle_target_event): Handle TARGET_WAITKIND_THREAD_CREATED and TARGET_WAITKIND_THREAD_EXITED. * server.h (report_thread_events): Declare. gdb/ChangeLog: 2015-11-30 Pedro Alves <palves@redhat.com> * NEWS (New commands): Mention "set/show remote thread-events" commands. (New remote packets): Mention thread created/exited stop reasons and QThreadEvents packet. * infrun.c (disable_thread_events): New function. (stop_all_threads): Disable/enable thread create/exit events. Handle TARGET_WAITKIND_THREAD_EXITED. (handle_inferior_event_1): Handle TARGET_WAITKIND_THREAD_CREATED and TARGET_WAITKIND_THREAD_EXITED. * remote.c (remove_child_of_pending_fork): Also remove threads of threads that have TARGET_WAITKIND_THREAD_EXITED events. (remote_parse_stop_reply): Handle "create" magic register. Handle 'w' stop reply. (initialize_remote): Install remote_thread_events as to_thread_events target hook. (remote_thread_events): New function. * target-delegates.c: Regenerate. * target.c (target_thread_events): New function. * target.h (struct target_ops) <to_thread_events>: New field. (target_thread_events): Declare. * target/waitstatus.c (target_waitstatus_to_string): Handle TARGET_WAITKIND_THREAD_CREATED and TARGET_WAITKIND_THREAD_EXITED. * target/waitstatus.h (enum target_waitkind) <TARGET_WAITKIND_THREAD_CREATED, TARGET_WAITKIND_THREAD_EXITED): New values.		2015-11-30 18:40:30 +00:00
..
resume.h
target.h	Revert the previous 7 commits of: Validate binary before use	2015-07-15 20:27:32 +02:00
wait.h
waitstatus.c	Remote thread create/exit events	2015-11-30 18:40:30 +00:00
waitstatus.h	Remote thread create/exit events	2015-11-30 18:40:30 +00:00