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| author | Pedro Alves <pedro@palves.net> | 2020-07-04 19:31:21 +0100 |
|---|---|---|
| committer | Pedro Alves <palves@redhat.com> | 2020-07-10 23:49:34 +0100 |
| commit | 42bd97a6b1e5fa845af116ce52af1a8a3a58be7c (patch) | |
| tree | 5a37f0776f61dd71d9165418a063e92d47cea1a8 | |
| parent | 43667cc6f65e60e2c15f3bb84e45730b537db5fa (diff) | |
| download | binutils-42bd97a6b1e5fa845af116ce52af1a8a3a58be7c.zip binutils-42bd97a6b1e5fa845af116ce52af1a8a3a58be7c.tar.gz binutils-42bd97a6b1e5fa845af116ce52af1a8a3a58be7c.tar.bz2 | |
Avoid constant stream of TARGET_WAITKIND_NO_RESUMED
If we hit the synchronous execution command case described by
handle_no_resumed, and handle_no_resumed determines that the event
should be ignored, because it found a thread that is executing, we end
up in prepare_to_wait.
There, if the current target is not registered in the event loop right
now, we call mark_infrun_async_event_handler. With that event handler
marked, the event loop calls again into fetch_inferior_event, which
calls target_wait, which returns TARGET_WAITKIND_NO_RESUMED, and we
end up in handle_no_resumed, again ignoring the event and marking
infrun_async_event_handler. The result is that GDB is now always
keeping the CPU 100% busy in this loop, even though it continues to be
able to react to input and to real target events, because we still go
through the event-loop.
The problem is that marking of the infrun_async_event_handler in
prepare_to_wait. That is there to handle targets that don't support
asynchronous execution. So the correct predicate is whether async
execution is supported, not whether the target is async right now.
gdb/ChangeLog:
PR gdb/26199
* infrun.c (prepare_to_wait): Check target_can_async_p instead of
target_is_async_p.
| -rw-r--r-- | gdb/ChangeLog | 6 | ||||
| -rw-r--r-- | gdb/infrun.c | 6 |
2 files changed, 11 insertions, 1 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 679f2d2..09198ef 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,6 +1,12 @@ 2020-07-10 Pedro Alves <pedro@palves.net> PR gdb/26199 + * infrun.c (prepare_to_wait): Check target_can_async_p instead of + target_is_async_p. + +2020-07-10 Pedro Alves <pedro@palves.net> + + PR gdb/26199 * target.c (target_pass_ctrlc): Look at the inferior's non-exited threads, not all threads. diff --git a/gdb/infrun.c b/gdb/infrun.c index 6b655d4..a01e096 100644 --- a/gdb/infrun.c +++ b/gdb/infrun.c @@ -8116,7 +8116,11 @@ prepare_to_wait (struct execution_control_state *ecs) ecs->wait_some_more = 1; - if (!target_is_async_p ()) + /* If the target can't async, emulate it by marking the infrun event + handler such that as soon as we get back to the event-loop, we + immediately end up in fetch_inferior_event again calling + target_wait. */ + if (!target_can_async_p ()) mark_infrun_async_event_handler (); } |