[RFC][PATCH 09/10] fs: Remove unlikely() from fget_light()

Steven Rostedt
2010-12-07T02:13:44Z

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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