1 files changed, 56 insertions, 38 deletions

diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c
index ab0f6b449111..22e21dc9a037 100644
--- a/drivers/md/bcache/writeback.c
+++ b/drivers/md/bcache/writeback.c
@@ -292,14 +292,12 @@ 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_offset;
-        uint64_t stripe = offset;
+        unsigned stripe_offset, stripe, sectors_dirty;
 
         if (!d)
                 return;
 
-        do_div(stripe, d->stripe_size);
-
+        stripe = offset_to_stripe(d, offset);
         stripe_offset = offset & (d->stripe_size - 1);
 
         while (nr_sectors) {
@@ -309,7 +307,16 @@ void bcache_dev_sectors_dirty_add(struct cache_set *c, unsigned inode,
                 if (nr_sectors < 0)
                         s = -s;
 
-                atomic_add(s, d->stripe_sectors_dirty + stripe);
+                if (stripe >= d->nr_stripes)
+                        return;
+
+                sectors_dirty = atomic_add_return(s,
+                                        d->stripe_sectors_dirty + stripe);
+                if (sectors_dirty == d->stripe_size)
+                        set_bit(stripe, d->full_dirty_stripes);
+                else
+                        clear_bit(stripe, d->full_dirty_stripes);
+
                 nr_sectors -= s;
                 stripe_offset = 0;
                 stripe++;
@@ -321,59 +328,70 @@ static bool dirty_pred(struct keybuf *buf, struct bkey *k)
         return KEY_DIRTY(k);
 }
 
-static bool dirty_full_stripe_pred(struct keybuf *buf, struct bkey *k)
+static void refill_full_stripes(struct cached_dev *dc)
 {
-        uint64_t stripe = KEY_START(k);
-        unsigned nr_sectors = KEY_SIZE(k);
-        struct cached_dev *dc = container_of(buf, struct cached_dev,
-                                             writeback_keys);
+        struct keybuf *buf = &dc->writeback_keys;
+        unsigned start_stripe, stripe, next_stripe;
+        bool wrapped = false;
+
+        stripe = offset_to_stripe(&dc->disk, KEY_OFFSET(&buf->last_scanned));
 
-        if (!KEY_DIRTY(k))
-                return false;
+        if (stripe >= dc->disk.nr_stripes)
+                stripe = 0;
 
-        do_div(stripe, dc->disk.stripe_size);
+        start_stripe = stripe;
 
         while (1) {
-                if (atomic_read(dc->disk.stripe_sectors_dirty + stripe) ==
-                    dc->disk.stripe_size)
-                        return true;
+                stripe = find_next_bit(dc->disk.full_dirty_stripes,
+                                       dc->disk.nr_stripes, stripe);
 
-                if (nr_sectors <= dc->disk.stripe_size)
-                        return false;
+                if (stripe == dc->disk.nr_stripes)
+                        goto next;
 
-                nr_sectors -= dc->disk.stripe_size;
-                stripe++;
+                next_stripe = find_next_zero_bit(dc->disk.full_dirty_stripes,
+                                                 dc->disk.nr_stripes, stripe);
+
+                buf->last_scanned = KEY(dc->disk.id,
+                                        stripe * dc->disk.stripe_size, 0);
+
+                bch_refill_keybuf(dc->disk.c, buf,
+                                  &KEY(dc->disk.id,
+                                       next_stripe * dc->disk.stripe_size, 0),
+                                  dirty_pred);
+
+                if (array_freelist_empty(&buf->freelist))
+                        return;
+
+                stripe = next_stripe;
+next:
+                if (wrapped && stripe > start_stripe)
+                        return;
+
+                if (stripe == dc->disk.nr_stripes) {
+                        stripe = 0;
+                        wrapped = true;
+                }
         }
 }
 
 static bool refill_dirty(struct cached_dev *dc)
 {
         struct keybuf *buf = &dc->writeback_keys;
-        bool searched_from_start = false;
         struct bkey end = KEY(dc->disk.id, MAX_KEY_OFFSET, 0);
+        bool searched_from_start = false;
+
+        if (dc->partial_stripes_expensive) {
+                refill_full_stripes(dc);
+                if (array_freelist_empty(&buf->freelist))
+                        return false;
+        }
 
         if (bkey_cmp(&buf->last_scanned, &end) >= 0) {
                 buf->last_scanned = KEY(dc->disk.id, 0, 0);
                 searched_from_start = true;
         }
 
-        if (dc->partial_stripes_expensive) {
-                uint64_t i;
-
-                for (i = 0; i < dc->disk.nr_stripes; i++)
-                        if (atomic_read(dc->disk.stripe_sectors_dirty + i) ==
-                            dc->disk.stripe_size)
-                                goto full_stripes;
-
-                goto normal_refill;
-full_stripes:
-                searched_from_start = false;    /* not searching entire btree */
-                bch_refill_keybuf(dc->disk.c, buf, &end,
-                                  dirty_full_stripe_pred);
-        } else {
-normal_refill:
-                bch_refill_keybuf(dc->disk.c, buf, &end, dirty_pred);
-        }
+        bch_refill_keybuf(dc->disk.c, buf, &end, dirty_pred);
 
         return bkey_cmp(&buf->last_scanned, &end) >= 0 && searched_from_start;
 }