From 279afbad4e54acbd61bf88a54a73af3bbfdeb5dd Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Wed, 5 Jun 2013 06:21:07 -0700 Subject: bcache: Track dirty data by stripe To make background writeback aware of raid5/6 stripes, we first need to track the amount of dirty data within each stripe - we do this by breaking up the existing sectors_dirty into per stripe atomic_ts Signed-off-by: Kent Overstreet --- drivers/md/bcache/writeback.c | 40 ++++++++++++++++++++++++++++++++++------ 1 file changed, 34 insertions(+), 6 deletions(-) (limited to 'drivers/md/bcache/writeback.c') diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c index 553949eefd51..dd815475c524 100644 --- a/drivers/md/bcache/writeback.c +++ b/drivers/md/bcache/writeback.c @@ -9,6 +9,7 @@ #include "bcache.h" #include "btree.h" #include "debug.h" +#include "writeback.h" #include @@ -38,7 +39,7 @@ static void __update_writeback_rate(struct cached_dev *dc) int change = 0; int64_t error; - int64_t dirty = atomic_long_read(&dc->disk.sectors_dirty); + int64_t dirty = bcache_dev_sectors_dirty(&dc->disk); int64_t derivative = dirty - dc->disk.sectors_dirty_last; dc->disk.sectors_dirty_last = dirty; @@ -183,10 +184,8 @@ void bch_writeback_queue(struct cached_dev *dc) } } -void bch_writeback_add(struct cached_dev *dc, unsigned sectors) +void bch_writeback_add(struct cached_dev *dc) { - atomic_long_add(sectors, &dc->disk.sectors_dirty); - if (!atomic_read(&dc->has_dirty) && !atomic_xchg(&dc->has_dirty, 1)) { atomic_inc(&dc->count); @@ -205,6 +204,34 @@ void bch_writeback_add(struct cached_dev *dc, unsigned sectors) } } +void bcache_dev_sectors_dirty_add(struct cache_set *c, unsigned inode, + uint64_t offset, int nr_sectors) +{ + struct bcache_device *d = c->devices[inode]; + unsigned stripe_size, stripe_offset; + uint64_t stripe; + + if (!d) + return; + + stripe_size = 1 << d->stripe_size_bits; + stripe = offset >> d->stripe_size_bits; + stripe_offset = offset & (stripe_size - 1); + + while (nr_sectors) { + int s = min_t(unsigned, abs(nr_sectors), + stripe_size - stripe_offset); + + if (nr_sectors < 0) + s = -s; + + atomic_add(s, d->stripe_sectors_dirty + stripe); + nr_sectors -= s; + stripe_offset = 0; + stripe++; + } +} + /* Background writeback - IO loop */ static void dirty_io_destructor(struct closure *cl) @@ -392,8 +419,9 @@ static int bch_btree_sectors_dirty_init(struct btree *b, struct btree_op *op, break; if (KEY_DIRTY(k)) - atomic_long_add(KEY_SIZE(k), - &dc->disk.sectors_dirty); + bcache_dev_sectors_dirty_add(b->c, dc->disk.id, + KEY_START(k), + KEY_SIZE(k)); } else { btree(sectors_dirty_init, k, b, op, dc); if (KEY_INODE(k) > dc->disk.id) -- cgit v1.2.3