[PATCH] vfs: does call expand_files when needed

[Liu Aleaxander <aleaxander@gmail.com>]

From: Liu Aleaxander <Aleaxander@gmail.com>
Date: Wed, 18 Nov 2009 10:59:09 +0800
Subject: [PATCH] vfs: does call expand_files when needed

I don't think we should call expand_files every time we open a
file for a new unused fd, so does the expand when necessary.

Signed-off-by: Liu Aleaxander <Aleaxander@gmail.com>
---
 fs/file.c |   27 ++++++++++++++-------------
 1 files changed, 14 insertions(+), 13 deletions(-)

diff --git a/fs/file.c b/fs/file.c
index 87e1290..3f3d0fc 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -452,22 +452,22 @@ repeat:
 	if (fd < files->next_fd)
 		fd = files->next_fd;

-	if (fd < fdt->max_fds)
+	if (likely(fd < fdt->max_fds)) {
 		fd = find_next_zero_bit(fdt->open_fds->fds_bits,
 					   fdt->max_fds, fd);
-
-	error = expand_files(files, fd);
-	if (error < 0)
-		goto out;
-
-	/*
-	 * If we needed to expand the fs array we
-	 * might have blocked - try again.
-	 */
-	if (error)
-		goto repeat;
-
+	} else {
+		error = expand_files(files, fd);
+		if (error < 0)
+			goto out;
+		
+		/*
+		 * If we needed to expand the fs array we
+		 * might have blocked - try again.
+		 */
+		if (error)
+			goto repeat;
+	}
+		
 	if (start <= files->next_fd)
 		files->next_fd = fd + 1;

-- 
1.6.2.5

--
regards
Liu Aleaxander