unwind: Add comment to unwind_deferred_task_exit()

Explain why unwind_deferred_task_exit() exist and its constraints.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Link: https://patch.msgid.link/20250924080118.893367437@infradead.org
This commit is contained in:
Peter Zijlstra 2025-09-22 15:46:27 +02:00
parent 52a1ec718b
commit ae577ea0bc
1 changed files with 6 additions and 1 deletions

View File

@ -939,7 +939,6 @@ void __noreturn do_exit(long code)
tsk->exit_code = code;
taskstats_exit(tsk, group_dead);
unwind_deferred_task_exit(tsk);
trace_sched_process_exit(tsk, group_dead);
/*
@ -950,6 +949,12 @@ void __noreturn do_exit(long code)
* gets woken up by child-exit notifications.
*/
perf_event_exit_task(tsk);
/*
* PF_EXITING (above) ensures unwind_deferred_request() will no
* longer add new unwinds. While exit_mm() (below) will destroy the
* abaility to do unwinds. So flush any pending unwinds here.
*/
unwind_deferred_task_exit(tsk);
exit_mm();