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

From: Steven Rostedt
Date: Mon Dec 06 2010 - 21:13:49 EST


From: Steven Rostedt <srostedt@xxxxxxxxxx>

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@xxxxxxxxxxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
---
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


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/