diff options
| author | Minchan Kim <minchan@kernel.org> | 2017-11-16 02:33:04 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-11-16 03:21:02 +0100 |
| commit | 539a6fea7fdcade532bd3e77be2862a683f8f0c9 (patch) | |
| tree | f3255c208ee4803cea857226b880a9838eccd2c8 | |
| parent | bdi: introduce BDI_CAP_SYNCHRONOUS_IO (diff) | |
| download | linux-539a6fea7fdcade532bd3e77be2862a683f8f0c9.tar.xz linux-539a6fea7fdcade532bd3e77be2862a683f8f0c9.zip | |
mm, swap: introduce SWP_SYNCHRONOUS_IO
If rw-page based fast storage is used for swap devices, we need to
detect it to enhance swap IO operations. This patch is preparation for
optimizing of swap-in operation with next patch.
Link: http://lkml.kernel.org/r/1505886205-9671-4-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | include/linux/swap.h | 3 | ||||
| -rw-r--r-- | mm/swapfile.c | 3 |
2 files changed, 5 insertions, 1 deletions
diff --git a/include/linux/swap.h b/include/linux/swap.h index f02fb5db8914..933d7c0c3542 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -171,8 +171,9 @@ enum { SWP_AREA_DISCARD = (1 << 8), /* single-time swap area discards */ SWP_PAGE_DISCARD = (1 << 9), /* freed swap page-cluster discards */ SWP_STABLE_WRITES = (1 << 10), /* no overwrite PG_writeback pages */ + SWP_SYNCHRONOUS_IO = (1 << 11), /* synchronous IO is efficient */ /* add others here before... */ - SWP_SCANNING = (1 << 11), /* refcount in scan_swap_map */ + SWP_SCANNING = (1 << 12), /* refcount in scan_swap_map */ }; #define SWAP_CLUSTER_MAX 32UL diff --git a/mm/swapfile.c b/mm/swapfile.c index e47a21e64764..cb08fa65819f 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -3169,6 +3169,9 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) if (bdi_cap_stable_pages_required(inode_to_bdi(inode))) p->flags |= SWP_STABLE_WRITES; + if (bdi_cap_synchronous_io(inode_to_bdi(inode))) + p->flags |= SWP_SYNCHRONOUS_IO; + if (p->bdev && blk_queue_nonrot(bdev_get_queue(p->bdev))) { int cpu; unsigned long ci, nr_cluster; |