From: Christoph Lameter <cl@linux.com>
To: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: David Rientjes <rientjes@google.com>, torvalds@linux-foundation.org
Cc: Andi Kleen <andi@firstfloor.org>
Cc: tj@kernel.org
Cc: Metathronius Galabant <m.galabant@googlemail.com>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Adrian Drzewiecki <z@drze.net>
Cc: linux-kernel@vger.kernel.org
Subject: [slub p4 2/7] slub: Remove useless statements in __slab_alloc
Date: Tue, 09 Aug 2011 16:12:23 -0500 [thread overview]
Message-ID: <20110809211259.776343341@linux.com> (raw)
In-Reply-To: 20110809211221.831975979@linux.com
[-- Attachment #1: remove_useless_page_null --]
[-- Type: text/plain, Size: 1155 bytes --]
Two statements in __slab_alloc() do not have any effect.
1. c->page is already set to NULL by deactivate_slab() called right before.
2. gfpflags are masked in new_slab() before being passed to the page
allocator. There is no need to mask gfpflags in __slab_alloc in particular
since most frequent processing in __slab_alloc does not require the use of a
gfpmask.
Cc: torvalds@linux-foundation.org
Signed-off-by: Christoph Lameter <cl@linux.com>
---
mm/slub.c | 4 ----
1 file changed, 4 deletions(-)
Index: linux-2.6/mm/slub.c
===================================================================
--- linux-2.6.orig/mm/slub.c 2011-08-01 11:03:15.000000000 -0500
+++ linux-2.6/mm/slub.c 2011-08-01 11:04:06.385859038 -0500
@@ -2064,9 +2064,6 @@ static void *__slab_alloc(struct kmem_ca
c = this_cpu_ptr(s->cpu_slab);
#endif
- /* We handle __GFP_ZERO in the caller */
- gfpflags &= ~__GFP_ZERO;
-
page = c->page;
if (!page)
goto new_slab;
@@ -2163,7 +2160,6 @@ debug:
c->freelist = get_freepointer(s, object);
deactivate_slab(s, c);
- c->page = NULL;
c->node = NUMA_NO_NODE;
local_irq_restore(flags);
return object;
next prev parent reply other threads:[~2011-08-09 21:14 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-08-09 21:12 [slub p4 0/7] slub: per cpu partial lists V4 Christoph Lameter
2011-08-09 21:12 ` [slub p4 1/7] slub: free slabs without holding locks (V2) Christoph Lameter
2011-08-20 10:32 ` Pekka Enberg
2011-08-20 15:58 ` Christoph Lameter
2011-08-09 21:12 ` Christoph Lameter [this message]
2011-08-20 10:44 ` [slub p4 2/7] slub: Remove useless statements in __slab_alloc Pekka Enberg
2011-08-20 16:01 ` Christoph Lameter
2011-08-09 21:12 ` [slub p4 3/7] slub: Prepare inuse field in new_slab() Christoph Lameter
2011-08-09 21:12 ` [slub p4 4/7] slub: pass kmem_cache_cpu pointer to get_partial() Christoph Lameter
2011-08-09 21:12 ` [slub p4 5/7] slub: return object pointer from get_partial() / new_slab() Christoph Lameter
2011-08-09 21:12 ` [slub p4 6/7] slub: per cpu cache for partial pages Christoph Lameter
2011-08-20 10:40 ` Pekka Enberg
2011-08-20 16:00 ` Christoph Lameter
[not found] ` <CAF1ivSaH9fh6_QvuBkLc5t=zC4mPEAD5ZzsxOuPruDwG9MiZzw@mail.gmail.com>
2011-08-24 7:26 ` Lin Ming
2011-08-24 13:57 ` Christoph Lameter
2011-08-09 21:12 ` [slub p4 7/7] slub: update slabinfo tools to report per cpu partial list statistics Christoph Lameter
2011-08-13 18:28 ` [slub p4 0/7] slub: per cpu partial lists V4 David Rientjes
2011-08-15 8:44 ` Pekka Enberg
2011-08-15 14:29 ` Christoph Lameter
2011-08-20 10:48 ` Pekka Enberg
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=20110809211259.776343341@linux.com \
--to=cl@linux.com \
--cc=penberg@cs.helsinki.fi \
--cc=rientjes@google.com \
--cc=torvalds@linux-foundation.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;
as well as URLs for NNTP newsgroup(s).