From: "T.Zhou" <t1zhou@163.com>
To: peterz@infradead.org
Cc: mingo@redhat.com, linux-kernel@vger.kernel.org
Subject: [PATCH] sched: Assign !p->on_cpu to the second parameter of smp_cond_load_acquire()
Date: Fri, 1 Jul 2016 11:08:01 +0800 [thread overview]
Message-ID: <20160701030801.GA15593@root> (raw)
The second parameter of smp_cond_load_acquire() should be !p->on_cpu
cause remote wakeup need to ensure that: if the task is running on
prev cpu, it should be descheduled before doing the actual wakeup.
Signed-off-by: T.Zhou <t1zhou@163.com>
---
kernel/sched/core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 3387e4f..8e6fef6 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2047,7 +2047,7 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
* This ensures that tasks getting woken will be fully ordered against
* their previous state and preserve Program Order.
*/
- smp_cond_load_acquire(&p->on_cpu, !VAL);
+ smp_cond_load_acquire(&p->on_cpu, !p->on_cpu);
p->sched_contributes_to_load = !!task_contributes_to_load(p);
p->state = TASK_WAKING;
--
2.7.3
next reply other threads:[~2016-07-01 3:36 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-07-01 3:08 T.Zhou [this message]
2016-07-01 6:55 ` [PATCH] sched: Assign !p->on_cpu to the second parameter of smp_cond_load_acquire() Peter Zijlstra
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20160701030801.GA15593@root \
--to=t1zhou@163.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.