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| author | Joe Thornber <ejt@redhat.com> | 2016-12-15 10:57:31 +0100 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2017-03-07 19:28:31 +0100 |
| commit | b29d4986d0da1a27cd35917cdb433672f5c95d7f (patch) | |
| tree | a5d94b86cf1eb759bfef5761015135d747e80561 /drivers/md/dm-cache-metadata.h | |
| parent | dm bio prison v2: new interface for the bio prison (diff) | |
| download | linux-b29d4986d0da1a27cd35917cdb433672f5c95d7f.tar.xz linux-b29d4986d0da1a27cd35917cdb433672f5c95d7f.zip | |
dm cache: significant rework to leverage dm-bio-prison-v2
The cache policy interfaces have been updated to work well with the new
bio-prison v2 interface's ability to queue work immediately (promotion,
demotion, etc) -- overriding benefit being reduced latency on processing
IO through the cache. Previously such work would be left for the DM
cache core to queue on various lists and then process in batches later
-- this caused a serious delay in latency for IO driven by the cache.
The background tracker code was factored out so that all cache policies
can make use of it.
Also, the "cleaner" policy has been removed and is now a variant of the
smq policy that simply disallows migrations.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Diffstat (limited to 'drivers/md/dm-cache-metadata.h')
| -rw-r--r-- | drivers/md/dm-cache-metadata.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/md/dm-cache-metadata.h b/drivers/md/dm-cache-metadata.h index 4f07c08cf107..179ed5bf81a3 100644 --- a/drivers/md/dm-cache-metadata.h +++ b/drivers/md/dm-cache-metadata.h @@ -50,6 +50,8 @@ #define DM_CACHE_FEATURE_COMPAT_RO_SUPP 0UL #define DM_CACHE_FEATURE_INCOMPAT_SUPP 0UL +struct dm_cache_metadata; + /* * Reopens or creates a new, empty metadata volume. Returns an ERR_PTR on * failure. If reopening then features must match. |