* [PATCH] do_task_stat: don't take rcu_read_lock()
@ 2008-02-20 17:09 Oleg Nesterov
0 siblings, 0 replies; only message in thread
From: Oleg Nesterov @ 2008-02-20 17:09 UTC (permalink / raw)
To: Andrew Morton
Cc: Alan Cox, Eric W. Biederman, Paul E. McKenney, Pavel Emelyanov,
linux-kernel
(depends on "[PATCH 1/2] lock_task_sighand: add rcu lock/unlock",
http://marc.info/?l=linux-kernel&m=120335433821564)
lock_task_sighand() was changed, and do_task_stat() doesn't need rcu_read_lock
any longer. sighand->siglock protects all "interesting" fields.
Except: it doesn't protect ->tty->pgrp, but neither does rcu_read_lock(), this
should be fixed.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
--- MM/fs/proc/array.c~DTS 2008-02-17 23:40:07.000000000 +0300
+++ MM/fs/proc/array.c 2008-02-20 19:53:37.000000000 +0300
@@ -425,7 +425,6 @@ static int do_task_stat(struct seq_file
cutime = cstime = utime = stime = cputime_zero;
cgtime = gtime = cputime_zero;
- rcu_read_lock();
if (lock_task_sighand(task, &flags)) {
struct signal_struct *sig = task->signal;
@@ -469,7 +468,6 @@ static int do_task_stat(struct seq_file
unlock_task_sighand(task, &flags);
}
- rcu_read_unlock();
if (!whole || num_threads < 2)
wchan = get_wchan(task);
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2008-02-20 17:13 UTC | newest]
Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2008-02-20 17:09 [PATCH] do_task_stat: don't take rcu_read_lock() Oleg Nesterov
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®