diff options
| author | Oleg Nesterov <oleg@redhat.com> | 2024-01-23 16:34:00 +0100 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-02-07 21:20:33 -0800 |
| commit | c1be35a16b2f1fe21f4f26f9de030ad6eaaf6a25 (patch) | |
| tree | d7ca24b5723bb9e8aaec90de0e06f9d22c026972 | |
| parent | 7601df8031fd67310af891897ef6cc0df4209305 (diff) | |
exit: wait_task_zombie: kill the no longer necessary spin_lock_irq(siglock)
After the recent changes nobody use siglock to read the values protected
by stats_lock, we can kill spin_lock_irq(¤t->sighand->siglock) and
update the comment.
With this patch only __exit_signal() and thread_group_start_cputime() take
stats_lock under siglock.
Link: https://lkml.kernel.org/r/20240123153359.GA21866@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Dylan Hatch <dylanbhatch@google.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | kernel/exit.c | 10 |
1 files changed, 3 insertions, 7 deletions
diff --git a/kernel/exit.c b/kernel/exit.c index 3988a02efaef..dfb963d2f862 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -1127,17 +1127,14 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p) * and nobody can change them. * * psig->stats_lock also protects us from our sub-threads - * which can reap other children at the same time. Until - * we change k_getrusage()-like users to rely on this lock - * we have to take ->siglock as well. + * which can reap other children at the same time. * * We use thread_group_cputime_adjusted() to get times for * the thread group, which consolidates times for all threads * in the group including the group leader. */ thread_group_cputime_adjusted(p, &tgutime, &tgstime); - spin_lock_irq(¤t->sighand->siglock); - write_seqlock(&psig->stats_lock); + write_seqlock_irq(&psig->stats_lock); psig->cutime += tgutime + sig->cutime; psig->cstime += tgstime + sig->cstime; psig->cgtime += task_gtime(p) + sig->gtime + sig->cgtime; @@ -1160,8 +1157,7 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p) psig->cmaxrss = maxrss; task_io_accounting_add(&psig->ioac, &p->ioac); task_io_accounting_add(&psig->ioac, &sig->ioac); - write_sequnlock(&psig->stats_lock); - spin_unlock_irq(¤t->sighand->siglock); + write_sequnlock_irq(&psig->stats_lock); } if (wo->wo_rusage) |