btrfs: drop optimal argument from find_live_mirror()

Drop optimal argument from the function find_live_mirror() as we can
deduce it in the function itself. Also rename optimal to
preferred_mirror.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 82c21f6..73de042 100644 (file)
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -5275,10 +5275,11 @@ int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info, u64 logical, u64 len)
 
 static int find_live_mirror(struct btrfs_fs_info *fs_info,
                            struct map_lookup *map, int first,
-                           int optimal, int dev_replace_is_ongoing)
+                           int dev_replace_is_ongoing)
 {
        int i;
        int num_stripes;
+       int preferred_mirror;
        int tolerance;
        struct btrfs_device *srcdev;
 
@@ -5290,6 +5291,8 @@ static int find_live_mirror(struct btrfs_fs_info *fs_info,
        else
                num_stripes = map->num_stripes;
 
+       preferred_mirror = first + current->pid % num_stripes;
+
        if (dev_replace_is_ongoing &&
            fs_info->dev_replace.cont_reading_from_srcdev_mode ==
             BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID)
@@ -5303,9 +5306,9 @@ static int find_live_mirror(struct btrfs_fs_info *fs_info,
         * mirror is available
         */
        for (tolerance = 0; tolerance < 2; tolerance++) {
-               if (map->stripes[optimal].dev->bdev &&
-                   (tolerance || map->stripes[optimal].dev != srcdev))
-                       return optimal;
+               if (map->stripes[preferred_mirror].dev->bdev &&
+                   (tolerance || map->stripes[preferred_mirror].dev != srcdev))
+                       return preferred_mirror;
                for (i = first; i < first + num_stripes; i++) {
                        if (map->stripes[i].dev->bdev &&
                            (tolerance || map->stripes[i].dev != srcdev))
@@ -5316,7 +5319,7 @@ static int find_live_mirror(struct btrfs_fs_info *fs_info,
        /* we couldn't find one that doesn't fail.  Just return something
         * and the io error handling code will clean up eventually
         */
-       return optimal;
+       return preferred_mirror;
 }
 
 static inline int parity_smaller(u64 a, u64 b)
@@ -5843,7 +5846,6 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info,
                        stripe_index = mirror_num - 1;
                else {
                        stripe_index = find_live_mirror(fs_info, map, 0,
-                                           current->pid % map->num_stripes,
                                            dev_replace_is_ongoing);
                        mirror_num = stripe_index + 1;
                }
@@ -5871,8 +5873,6 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info,
                        int old_stripe_index = stripe_index;
                        stripe_index = find_live_mirror(fs_info, map,
                                              stripe_index,
-                                             stripe_index +
-                                             current->pid % map->sub_stripes,
                                              dev_replace_is_ongoing);
                        mirror_num = stripe_index - old_stripe_index + 1;
                }