Commit 87192a2a49c475cf322cb143e0fa63b0102d8567
Committed by
Linus Torvalds
Linus Torvalds
1 parent
ae55e1aaa7
Exists in
master
and in
6 other branches
vfs: cache request_queue in struct block_device
This makes it possible to get from the inode to the request_queue with one less cache miss. Used in followon optimization. The livetime of the pointer is the same as the gendisk. This assumes that the queue will always stay the same in the gendisk while it's visible to block_devices. I think that's safe correct? Signed-off-by: Andi Kleen <ak@linux.intel.com> Acked-by: Jeff Moyer <jmoyer@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Showing 2 changed files with 5 additions and 0 deletions Side-by-side Diff
fs/block_dev.c
| ... | ... | @@ -1139,6 +1139,7 @@ |
| 1139 | 1139 | mutex_lock_nested(&bdev->bd_mutex, for_part); |
| 1140 | 1140 | if (!bdev->bd_openers) { |
| 1141 | 1141 | bdev->bd_disk = disk; |
| 1142 | + bdev->bd_queue = disk->queue; | |
| 1142 | 1143 | bdev->bd_contains = bdev; |
| 1143 | 1144 | if (!partno) { |
| 1144 | 1145 | struct backing_dev_info *bdi; |
| ... | ... | @@ -1159,6 +1160,7 @@ |
| 1159 | 1160 | disk_put_part(bdev->bd_part); |
| 1160 | 1161 | bdev->bd_part = NULL; |
| 1161 | 1162 | bdev->bd_disk = NULL; |
| 1163 | + bdev->bd_queue = NULL; | |
| 1162 | 1164 | mutex_unlock(&bdev->bd_mutex); |
| 1163 | 1165 | disk_unblock_events(disk); |
| 1164 | 1166 | put_disk(disk); |
| ... | ... | @@ -1232,6 +1234,7 @@ |
| 1232 | 1234 | disk_put_part(bdev->bd_part); |
| 1233 | 1235 | bdev->bd_disk = NULL; |
| 1234 | 1236 | bdev->bd_part = NULL; |
| 1237 | + bdev->bd_queue = NULL; | |
| 1235 | 1238 | bdev_inode_switch_bdi(bdev->bd_inode, &default_backing_dev_info); |
| 1236 | 1239 | if (bdev != bdev->bd_contains) |
| 1237 | 1240 | __blkdev_put(bdev->bd_contains, mode, 1); |
include/linux/fs.h
| ... | ... | @@ -660,6 +660,7 @@ |
| 660 | 660 | * must be enforced here for CRIS, to let the least significant bit |
| 661 | 661 | * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON. |
| 662 | 662 | */ |
| 663 | +struct request_queue; | |
| 663 | 664 | |
| 664 | 665 | struct block_device { |
| 665 | 666 | dev_t bd_dev; /* not a kdev_t - it's a search key */ |
| ... | ... | @@ -682,6 +683,7 @@ |
| 682 | 683 | unsigned bd_part_count; |
| 683 | 684 | int bd_invalidated; |
| 684 | 685 | struct gendisk * bd_disk; |
| 686 | + struct request_queue * bd_queue; | |
| 685 | 687 | struct list_head bd_list; |
| 686 | 688 | /* |
| 687 | 689 | * Private data. You must have bd_claim'ed the block_device |