diff options
| author | Kent Overstreet <koverstreet@google.com> | 2013-06-05 15:24:39 +0200 |
|---|---|---|
| committer | Kent Overstreet <koverstreet@google.com> | 2013-06-27 06:58:04 +0200 |
| commit | 72c270612bd33192fa836ad0f2939af1ca218292 (patch) | |
| tree | 344129d75f3b5c0abcf77dd4b6340783a126cde8 /drivers/md/bcache/request.c | |
| parent | bcache: Track dirty data by stripe (diff) | |
| download | linux-72c270612bd33192fa836ad0f2939af1ca218292.tar.xz linux-72c270612bd33192fa836ad0f2939af1ca218292.zip | |
bcache: Write out full stripes
Now that we're tracking dirty data per stripe, we can add two
optimizations for raid5/6:
* If a stripe is already dirty, force writes to that stripe to
writeback mode - to help build up full stripes of dirty data
* When flushing dirty data, preferentially write out full stripes first
if there are any.
Signed-off-by: Kent Overstreet <koverstreet@google.com>
Diffstat (limited to 'drivers/md/bcache/request.c')
| -rw-r--r-- | drivers/md/bcache/request.c | 23 |
1 files changed, 7 insertions, 16 deletions
diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c index 017c95fced8e..17bd59704eba 100644 --- a/drivers/md/bcache/request.c +++ b/drivers/md/bcache/request.c @@ -22,8 +22,6 @@ #define CUTOFF_CACHE_ADD 95 #define CUTOFF_CACHE_READA 90 -#define CUTOFF_WRITEBACK 50 -#define CUTOFF_WRITEBACK_SYNC 75 struct kmem_cache *bch_search_cache; @@ -998,17 +996,6 @@ static void cached_dev_write_complete(struct closure *cl) cached_dev_bio_complete(cl); } -static bool should_writeback(struct cached_dev *dc, struct bio *bio) -{ - unsigned threshold = (bio->bi_rw & REQ_SYNC) - ? CUTOFF_WRITEBACK_SYNC - : CUTOFF_WRITEBACK; - - return !atomic_read(&dc->disk.detaching) && - cache_mode(dc, bio) == CACHE_MODE_WRITEBACK && - dc->disk.c->gc_stats.in_use < threshold; -} - static void request_write(struct cached_dev *dc, struct search *s) { struct closure *cl = &s->cl; @@ -1030,12 +1017,16 @@ static void request_write(struct cached_dev *dc, struct search *s) if (bio->bi_rw & REQ_DISCARD) goto skip; + if (should_writeback(dc, s->orig_bio, + cache_mode(dc, bio), + s->op.skip)) { + s->op.skip = false; + s->writeback = true; + } + if (s->op.skip) goto skip; - if (should_writeback(dc, s->orig_bio)) - s->writeback = true; - trace_bcache_write(s->orig_bio, s->writeback, s->op.skip); if (!s->writeback) { |