From: Steven Rostedt <rostedt@goodmis.org>
To: linux-kernel@vger.kernel.org
Cc: Al Viro <viro@zeniv.linux.org.uk>, Christoph Hellwig <hch@lst.de>,
Andrew Morton <akpm@linux-foundation.org>
Subject: [PATCH 2/2] fs: Remove unlikely() from fget_light()
Date: Mon, 13 Dec 2010 19:38:09 -0500 [thread overview]
Message-ID: <20101214004040.586626794@goodmis.org> (raw)
In-Reply-To: 20101214003807.693481687@goodmis.org
[-- Attachment #1: 0002-fs-Remove-unlikely-from-fget_light.patch --]
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From: Steven Rostedt <srostedt@redhat.com>
There's an unlikely() in fget_light() that assumes the file ref count
will be 1. Running the annotate branch profiler on a desktop that is
performing daily tasks (running firefox, evolution, xchat and is also part
of a distcc farm), it shows that the ref count is not 1 that often.
correct incorrect % Function File Line
------- --------- - -------- ---- ----
1035099358 6209599193 85 fget_light file_table.c 315
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
fs/file_table.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/fs/file_table.c b/fs/file_table.c
index c3dee38..c3e89ad 100644
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -311,7 +311,7 @@ struct file *fget_light(unsigned int fd, int *fput_needed)
struct files_struct *files = current->files;
*fput_needed = 0;
- if (likely((atomic_read(&files->count) == 1))) {
+ if (atomic_read(&files->count) == 1) {
file = fcheck_files(files, fd);
} else {
rcu_read_lock();
--
1.7.2.3
prev parent reply other threads:[~2010-12-14 0:40 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-12-14 0:38 [PATCH 0/2] fs: Removal of unlikely likelys Steven Rostedt
2010-12-14 0:38 ` [PATCH 1/2] fs: Remove unlikely() from fput_light() Steven Rostedt
2010-12-14 0:38 ` Steven Rostedt [this message]
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