diff options
| author | Josef Bacik | 2018-07-03 11:14:53 -0400 |
|---|---|---|
| committer | Jens Axboe | 2018-07-09 09:07:54 -0600 |
| commit | 0d1e0c7cd5909d6c6aa0957179318e13fcca971a (patch) | |
| tree | 891b19b5a5c21e0a9daddcf281892184113265dc | |
| parent | 903d23f0a354f226fa78f1c1c34b60aaf992e812 (diff) | |
blk: introduce REQ_SWAP
Just like REQ_META, it's important to know the IO coming down is swap
in order to guard against potential IO priority inversion issues with
cgroups. Add REQ_SWAP and use it for all swap IO, and add it to our
bio_issue_as_root_blkg helper.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | include/linux/blk-cgroup.h | 2 | ||||
| -rw-r--r-- | include/linux/blk_types.h | 3 | ||||
| -rw-r--r-- | mm/page_io.c | 2 |
3 files changed, 4 insertions, 3 deletions
diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h index b41292726c0f..a8f9ba8f33a4 100644 --- a/include/linux/blk-cgroup.h +++ b/include/linux/blk-cgroup.h @@ -254,7 +254,7 @@ static inline struct blkcg *bio_blkcg(struct bio *bio) */ static inline bool bio_issue_as_root_blkg(struct bio *bio) { - return (bio->bi_opf & REQ_META); + return (bio->bi_opf & (REQ_META | REQ_SWAP)) != 0; } /** diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index 3364d42ebe08..0ffc34c5cc83 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -329,7 +329,7 @@ enum req_flag_bits { /* for driver use */ __REQ_DRV, - + __REQ_SWAP, /* swapping request. */ __REQ_NR_BITS, /* stops here */ }; @@ -351,6 +351,7 @@ enum req_flag_bits { #define REQ_NOUNMAP (1ULL << __REQ_NOUNMAP) #define REQ_DRV (1ULL << __REQ_DRV) +#define REQ_SWAP (1ULL << __REQ_SWAP) #define REQ_FAILFAST_MASK \ (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER) diff --git a/mm/page_io.c b/mm/page_io.c index b41cf9644585..a552cb37e220 100644 --- a/mm/page_io.c +++ b/mm/page_io.c @@ -338,7 +338,7 @@ int __swap_writepage(struct page *page, struct writeback_control *wbc, ret = -ENOMEM; goto out; } - bio->bi_opf = REQ_OP_WRITE | wbc_to_write_flags(wbc); + bio->bi_opf = REQ_OP_WRITE | REQ_SWAP | wbc_to_write_flags(wbc); count_swpout_vm_event(page); set_page_writeback(page); unlock_page(page); |