From 981aa8c091e164ea51dd1e81b71a1f3852bbcceb Mon Sep 17 00:00:00 2001 From: Nicholas Swenson Date: Thu, 7 Nov 2013 17:53:19 -0800 Subject: [PATCH] bcache: bugfix - moving_gc now moves only correct buckets Removed gc_move_threshold because picking buckets only by threshold could lead moving extra buckets (ei. if there are buckets at the threshold that aren't supposed to be moved do to space considerations). This is replaced by a GC_MOVE bit in the gc_mark bitmask. Now only marked buckets get moved. Signed-off-by: Nicholas Swenson Signed-off-by: Kent Overstreet --- drivers/md/bcache/alloc.c | 2 ++ drivers/md/bcache/bcache.h | 6 +++--- drivers/md/bcache/movinggc.c | 8 +++----- 3 files changed, 8 insertions(+), 8 deletions(-) diff --git a/drivers/md/bcache/alloc.c b/drivers/md/bcache/alloc.c index 2b46bf1d7e40..4c9852d92b0a 100644 --- a/drivers/md/bcache/alloc.c +++ b/drivers/md/bcache/alloc.c @@ -421,9 +421,11 @@ out: if (watermark <= WATERMARK_METADATA) { SET_GC_MARK(b, GC_MARK_METADATA); + SET_GC_MOVE(b, 0); b->prio = BTREE_PRIO; } else { SET_GC_MARK(b, GC_MARK_RECLAIMABLE); + SET_GC_MOVE(b, 0); b->prio = INITIAL_PRIO; } diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h index 4beb55a0ff30..a7b1a7631ed2 100644 --- a/drivers/md/bcache/bcache.h +++ b/drivers/md/bcache/bcache.h @@ -197,7 +197,7 @@ struct bucket { uint8_t disk_gen; uint8_t last_gc; /* Most out of date gen in the btree */ uint8_t gc_gen; - uint16_t gc_mark; + uint16_t gc_mark; /* Bitfield used by GC. See below for field */ }; /* @@ -209,7 +209,8 @@ BITMASK(GC_MARK, struct bucket, gc_mark, 0, 2); #define GC_MARK_RECLAIMABLE 0 #define GC_MARK_DIRTY 1 #define GC_MARK_METADATA 2 -BITMASK(GC_SECTORS_USED, struct bucket, gc_mark, 2, 14); +BITMASK(GC_SECTORS_USED, struct bucket, gc_mark, 2, 13); +BITMASK(GC_MOVE, struct bucket, gc_mark, 15, 1); #include "journal.h" #include "stats.h" @@ -445,7 +446,6 @@ struct cache { * call prio_write() to keep gens from wrapping. */ uint8_t need_save_prio; - unsigned gc_move_threshold; /* * If nonzero, we know we aren't going to find any buckets to invalidate diff --git a/drivers/md/bcache/movinggc.c b/drivers/md/bcache/movinggc.c index 46c952379fab..30f347d4e609 100644 --- a/drivers/md/bcache/movinggc.c +++ b/drivers/md/bcache/movinggc.c @@ -25,10 +25,9 @@ static bool moving_pred(struct keybuf *buf, struct bkey *k) unsigned i; for (i = 0; i < KEY_PTRS(k); i++) { - struct cache *ca = PTR_CACHE(c, k, i); struct bucket *g = PTR_BUCKET(c, k, i); - if (GC_SECTORS_USED(g) < ca->gc_move_threshold) + if (GC_MOVE(g)) return true; } @@ -227,9 +226,8 @@ void bch_moving_gc(struct cache_set *c) sectors_to_move -= GC_SECTORS_USED(b); } - ca->gc_move_threshold = bucket_heap_top(ca); - - pr_debug("threshold %u", ca->gc_move_threshold); + while (heap_pop(&ca->heap, b, bucket_cmp)) + SET_GC_MOVE(b, 1); } mutex_unlock(&c->bucket_lock); -- 2.20.1