From: Sasha Levin <sasha.levin@oracle.com>
To: linux-kernel@vger.kernel.org
Cc: iamjoonsoo.kim@lge.com, cl@linux.com, brouer@redhat.com,
akpm@linux-foundation.org, Sasha Levin <sasha.levin@oracle.com>
Subject: [PATCH] mm/slub: use unchecked percpu access within preemptible sections
Date: Tue, 20 Jan 2015 23:31:43 -0500 [thread overview]
Message-ID: <1421814703-1869-1-git-send-email-sasha.levin@oracle.com> (raw)
Commit "mm/slub: optimize alloc/free fastpath by removing preemption on/off"
has added access to percpu memory while the code is preemptible.
While those accesses are okay, this creates a huge amount of warnings from
the code that checks for that.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
---
mm/slub.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/mm/slub.c b/mm/slub.c
index 907fabe..9b72b9c 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2431,8 +2431,8 @@ redo:
* to check if it is matched or not.
*/
do {
- tid = this_cpu_read(s->cpu_slab->tid);
- c = this_cpu_ptr(s->cpu_slab);
+ tid = raw_cpu_read(s->cpu_slab->tid);
+ c = raw_cpu_ptr(s->cpu_slab);
} while (IS_ENABLED(CONFIG_PREEMPT) && unlikely(tid != c->tid));
/*
@@ -2700,8 +2700,8 @@ redo:
* during the cmpxchg then the free will succedd.
*/
do {
- tid = this_cpu_read(s->cpu_slab->tid);
- c = this_cpu_ptr(s->cpu_slab);
+ tid = raw_cpu_read(s->cpu_slab->tid);
+ c = raw_cpu_ptr(s->cpu_slab);
} while (IS_ENABLED(CONFIG_PREEMPT) && unlikely(tid != c->tid));
/* Same with comment on barrier() in slab_alloc_node() */
--
1.7.10.4
next reply other threads:[~2015-01-21 4:32 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-01-21 4:31 Sasha Levin [this message]
2015-01-22 1:59 ` Joonsoo Kim
2015-01-22 2:27 ` Sasha Levin
2015-01-22 5:13 ` Joonsoo Kim
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=1421814703-1869-1-git-send-email-sasha.levin@oracle.com \
--to=sasha.levin@oracle.com \
--cc=akpm@linux-foundation.org \
--cc=brouer@redhat.com \
--cc=cl@linux.com \
--cc=iamjoonsoo.kim@lge.com \
--cc=linux-kernel@vger.kernel.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 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®