From: "Theodore Ts'o" <tytso@mit.edu>
To: Christoph Lameter <cl@linux-foundation.org>,
Pekka Enberg <penberg@cs.helsinki.fi>,
Matt Mackall <mpm@selenic.com>,
linux-mm@kvack.org
Cc: linux-kernel@vger.kernel.org
Subject: Should we be using unlikely() around tests of GFP_ZERO?
Date: Sun, 02 Jan 2011 18:48:01 -0500 [thread overview]
Message-ID: <E1PZXeb-0004AV-2b@tytso-glaptop> (raw)
Given the patches being busily submitted by trivial patch submitters to
make use kmem_cache_zalloc(), et. al, I believe we should remove the
unlikely() tests around the (gfp_flags & __GFP_ZERO) tests, such as:
- if (unlikely((flags & __GFP_ZERO) && objp))
+ if ((flags & __GFP_ZERO) && objp)
memset(objp, 0, obj_size(cachep));
Agreed? If so, I'll send a patch...
- Ted
WARNING: multiple messages have this Message-ID (diff)
From: "Theodore Ts'o" <tytso@mit.edu>
To: Christoph Lameter <cl@linux-foundation.org>,
Pekka Enberg <penberg@cs.helsinki.fi>,
Matt Mackall <mpm@selenic.com>,
linux-mm@kvack.org
Cc: linux-kernel@vger.kernel.org
Subject: Should we be using unlikely() around tests of GFP_ZERO?
Date: Sun, 02 Jan 2011 18:48:01 -0500 [thread overview]
Message-ID: <E1PZXeb-0004AV-2b@tytso-glaptop> (raw)
Given the patches being busily submitted by trivial patch submitters to
make use kmem_cache_zalloc(), et. al, I believe we should remove the
unlikely() tests around the (gfp_flags & __GFP_ZERO) tests, such as:
- if (unlikely((flags & __GFP_ZERO) && objp))
+ if ((flags & __GFP_ZERO) && objp)
memset(objp, 0, obj_size(cachep));
Agreed? If so, I'll send a patch...
- Ted
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next reply other threads:[~2011-01-03 2:50 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-01-02 23:48 Theodore Ts'o [this message]
2011-01-02 23:48 ` Should we be using unlikely() around tests of GFP_ZERO? Theodore Ts'o
2011-01-03 3:46 ` Minchan Kim
2011-01-03 3:46 ` Minchan Kim
2011-01-03 7:40 ` Pekka Enberg
2011-01-03 7:40 ` Pekka Enberg
2011-01-03 13:45 ` Steven Rostedt
2011-01-03 13:45 ` Steven Rostedt
2011-01-03 14:10 ` Pekka Enberg
2011-01-03 14:10 ` Pekka Enberg
2011-01-03 14:26 ` Steven Rostedt
2011-01-03 14:26 ` Steven Rostedt
2011-01-03 13:58 ` Ted Ts'o
2011-01-03 13:58 ` Ted Ts'o
2011-01-03 14:09 ` Pekka Enberg
2011-01-03 14:09 ` Pekka Enberg
2011-01-03 17:23 ` Matt Mackall
2011-01-03 17:23 ` Matt Mackall
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