linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: WANG Chao <wcwxyz@gmail.com>
To: Ingo Molnar <mingo@redhat.com>, Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Subject: [PATCH v3] sched: unlikely corrupted stack end
Date: Wed, 15 Jun 2016 16:53:50 +0800	[thread overview]
Message-ID: <20160615085350.32777-1-wcwxyz@gmail.com> (raw)
In-Reply-To: <20160615082554.GA18748@gmail.com>

unlikely() was dropped in commit ce03e4137bb2 ("sched/core: Drop
unlikely behind BUG_ON()"), but commit 29d6455178a0 ("sched: panic on
corrupted stack end") dropped BUG_ON() and called panic directly.

Now we should bring unlikely() back for branch prediction. While we're
at it, it's better and cleaner to add unlikely() to
task_stack_end_corrupted() macro.

Signed-off-by: WANG Chao <wcwxyz@gmail.com>
---
 include/linux/sched.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 6e42ada26345..74a02bf30827 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -2998,7 +2998,7 @@ static inline unsigned long *end_of_stack(struct task_struct *p)
 
 #endif
 #define task_stack_end_corrupted(task) \
-		(*(end_of_stack(task)) != STACK_END_MAGIC)
+		(unlikely(*(end_of_stack(task)) != STACK_END_MAGIC))
 
 static inline int object_is_on_stack(void *obj)
 {
-- 
2.9.0

  reply	other threads:[~2016-06-15  8:54 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-06-14  6:43 [PATCH] " WANG Chao
2016-06-14  7:43 ` Ingo Molnar
2016-06-14  8:17 ` Peter Zijlstra
2016-06-14  8:24 ` [PATCH v2] " WANG Chao
2016-06-14  8:56   ` Ingo Molnar
2016-06-14 10:17     ` WANG Chao
2016-06-14 10:26       ` Ingo Molnar
2016-06-14 16:55         ` WANG Chao
2016-06-15  8:25           ` Ingo Molnar
2016-06-15  8:53             ` WANG Chao [this message]
2016-06-14  9:08   ` kbuild test robot

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=20160615085350.32777-1-wcwxyz@gmail.com \
    --to=wcwxyz@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=peterz@infradead.org \
    --subject='Re: [PATCH v3] sched: unlikely corrupted stack end' \
    /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

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).