[PATCH] Decrease number of pointer derefs in multipath.c
authorJesper Juhl <jesper.juhl@gmail.com>
Tue, 10 Jan 2006 04:54:44 +0000 (20:54 -0800)
committerLinus Torvalds <torvalds@g5.osdl.org>
Tue, 10 Jan 2006 16:02:01 +0000 (08:02 -0800)
Decrease the number of pointer derefs in drivers/md/multipath.c

Benefits of the patch:
 - Fewer pointer dereferences should make the code slightly faster.
 - Size of generated code is smaller
 - improved readability

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Alasdair G Kergon <agk@redhat.com>
Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
drivers/md/multipath.c

index e6aa309a66d7b7a4d71525702706f1bae99a8461..96f7af4ae400ad4eaa2dd7d47d9e1a1ce1ca3efa 100644 (file)
@@ -303,6 +303,7 @@ static void print_multipath_conf (multipath_conf_t *conf)
 static int multipath_add_disk(mddev_t *mddev, mdk_rdev_t *rdev)
 {
        multipath_conf_t *conf = mddev->private;
+       struct request_queue *q;
        int found = 0;
        int path;
        struct multipath_info *p;
@@ -311,8 +312,8 @@ static int multipath_add_disk(mddev_t *mddev, mdk_rdev_t *rdev)
 
        for (path=0; path<mddev->raid_disks; path++) 
                if ((p=conf->multipaths+path)->rdev == NULL) {
-                       blk_queue_stack_limits(mddev->queue,
-                                              rdev->bdev->bd_disk->queue);
+                       q = rdev->bdev->bd_disk->queue;
+                       blk_queue_stack_limits(mddev->queue, q);
 
                /* as we don't honour merge_bvec_fn, we must never risk
                 * violating it, so limit ->max_sector to one PAGE, as
@@ -320,7 +321,7 @@ static int multipath_add_disk(mddev_t *mddev, mdk_rdev_t *rdev)
                 * (Note: it is very unlikely that a device with
                 * merge_bvec_fn will be involved in multipath.)
                 */
-                       if (rdev->bdev->bd_disk->queue->merge_bvec_fn &&
+                       if (q->merge_bvec_fn &&
                            mddev->queue->max_sectors > (PAGE_SIZE>>9))
                                blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);