coredump: change wait_for_dump_helpers() to use wait_event_interruptible()
wait_for_dump_helpers() calls wake_up/kill_fasync from inside the
wait_event-like loop. This is not needed and in fact this is not
strictly correct, we can/should do this only once after we change
pipe->writers. We could even check if it becomes zero.
Change this code to use use wait_event_interruptible(), this can also
help to make this wait freezable.
With this patch we check pipe->readers without pipe_lock(), this is
fine. Once we see pipe->readers == 1 we know that the handler
decremented the counter, this is all we need.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Mandeep Singh Baines <msb@chromium.org>
Cc: Neil Horman <nhorman@redhat.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 file changed