diff options
Diffstat (limited to 'drivers/md/bcache/alloc.c')
-rw-r--r-- | drivers/md/bcache/alloc.c | 89 |
1 files changed, 59 insertions, 30 deletions
diff --git a/drivers/md/bcache/alloc.c b/drivers/md/bcache/alloc.c index 4c9852d92b0..c0d37d08244 100644 --- a/drivers/md/bcache/alloc.c +++ b/drivers/md/bcache/alloc.c @@ -132,10 +132,16 @@ bool bch_bucket_add_unused(struct cache *ca, struct bucket *b) { BUG_ON(GC_MARK(b) || GC_SECTORS_USED(b)); - if (fifo_used(&ca->free) > ca->watermark[WATERMARK_MOVINGGC] && - CACHE_REPLACEMENT(&ca->sb) == CACHE_REPLACEMENT_FIFO) - return false; + if (CACHE_REPLACEMENT(&ca->sb) == CACHE_REPLACEMENT_FIFO) { + unsigned i; + + for (i = 0; i < RESERVE_NONE; i++) + if (!fifo_full(&ca->free[i])) + goto add; + return false; + } +add: b->prio = 0; if (can_inc_bucket_gen(b) && @@ -162,8 +168,21 @@ static void invalidate_one_bucket(struct cache *ca, struct bucket *b) fifo_push(&ca->free_inc, b - ca->buckets); } -#define bucket_prio(b) \ - (((unsigned) (b->prio - ca->set->min_prio)) * GC_SECTORS_USED(b)) +/* + * Determines what order we're going to reuse buckets, smallest bucket_prio() + * first: we also take into account the number of sectors of live data in that + * bucket, and in order for that multiply to make sense we have to scale bucket + * + * Thus, we scale the bucket priorities so that the bucket with the smallest + * prio is worth 1/8th of what INITIAL_PRIO is worth. + */ + +#define bucket_prio(b) \ +({ \ + unsigned min_prio = (INITIAL_PRIO - ca->set->min_prio) / 8; \ + \ + (b->prio - ca->set->min_prio + min_prio) * GC_SECTORS_USED(b); \ +}) #define bucket_max_cmp(l, r) (bucket_prio(l) < bucket_prio(r)) #define bucket_min_cmp(l, r) (bucket_prio(l) > bucket_prio(r)) @@ -304,6 +323,21 @@ do { \ __set_current_state(TASK_RUNNING); \ } while (0) +static int bch_allocator_push(struct cache *ca, long bucket) +{ + unsigned i; + + /* Prios/gens are actually the most important reserve */ + if (fifo_push(&ca->free[RESERVE_PRIO], bucket)) + return true; + + for (i = 0; i < RESERVE_NR; i++) + if (fifo_push(&ca->free[i], bucket)) + return true; + + return false; +} + static int bch_allocator_thread(void *arg) { struct cache *ca = arg; @@ -336,9 +370,7 @@ static int bch_allocator_thread(void *arg) mutex_lock(&ca->set->bucket_lock); } - allocator_wait(ca, !fifo_full(&ca->free)); - - fifo_push(&ca->free, bucket); + allocator_wait(ca, bch_allocator_push(ca, bucket)); wake_up(&ca->set->bucket_wait); } @@ -365,34 +397,29 @@ static int bch_allocator_thread(void *arg) } } -long bch_bucket_alloc(struct cache *ca, unsigned watermark, bool wait) +long bch_bucket_alloc(struct cache *ca, unsigned reserve, bool wait) { DEFINE_WAIT(w); struct bucket *b; long r; /* fastpath */ - if (fifo_used(&ca->free) > ca->watermark[watermark]) { - fifo_pop(&ca->free, r); + if (fifo_pop(&ca->free[RESERVE_NONE], r) || + fifo_pop(&ca->free[reserve], r)) goto out; - } if (!wait) return -1; - while (1) { - if (fifo_used(&ca->free) > ca->watermark[watermark]) { - fifo_pop(&ca->free, r); - break; - } - + do { prepare_to_wait(&ca->set->bucket_wait, &w, TASK_UNINTERRUPTIBLE); mutex_unlock(&ca->set->bucket_lock); schedule(); mutex_lock(&ca->set->bucket_lock); - } + } while (!fifo_pop(&ca->free[RESERVE_NONE], r) && + !fifo_pop(&ca->free[reserve], r)); finish_wait(&ca->set->bucket_wait, &w); out: @@ -401,12 +428,14 @@ out: if (expensive_debug_checks(ca->set)) { size_t iter; long i; + unsigned j; for (iter = 0; iter < prio_buckets(ca) * 2; iter++) BUG_ON(ca->prio_buckets[iter] == (uint64_t) r); - fifo_for_each(i, &ca->free, iter) - BUG_ON(i == r); + for (j = 0; j < RESERVE_NR; j++) + fifo_for_each(i, &ca->free[j], iter) + BUG_ON(i == r); fifo_for_each(i, &ca->free_inc, iter) BUG_ON(i == r); fifo_for_each(i, &ca->unused, iter) @@ -419,7 +448,7 @@ out: SET_GC_SECTORS_USED(b, ca->sb.bucket_size); - if (watermark <= WATERMARK_METADATA) { + if (reserve <= RESERVE_PRIO) { SET_GC_MARK(b, GC_MARK_METADATA); SET_GC_MOVE(b, 0); b->prio = BTREE_PRIO; @@ -445,7 +474,7 @@ void bch_bucket_free(struct cache_set *c, struct bkey *k) } } -int __bch_bucket_alloc_set(struct cache_set *c, unsigned watermark, +int __bch_bucket_alloc_set(struct cache_set *c, unsigned reserve, struct bkey *k, int n, bool wait) { int i; @@ -459,7 +488,7 @@ int __bch_bucket_alloc_set(struct cache_set *c, unsigned watermark, for (i = 0; i < n; i++) { struct cache *ca = c->cache_by_alloc[i]; - long b = bch_bucket_alloc(ca, watermark, wait); + long b = bch_bucket_alloc(ca, reserve, wait); if (b == -1) goto err; @@ -478,12 +507,12 @@ err: return -1; } -int bch_bucket_alloc_set(struct cache_set *c, unsigned watermark, +int bch_bucket_alloc_set(struct cache_set *c, unsigned reserve, struct bkey *k, int n, bool wait) { int ret; mutex_lock(&c->bucket_lock); - ret = __bch_bucket_alloc_set(c, watermark, k, n, wait); + ret = __bch_bucket_alloc_set(c, reserve, k, n, wait); mutex_unlock(&c->bucket_lock); return ret; } @@ -573,8 +602,8 @@ bool bch_alloc_sectors(struct cache_set *c, struct bkey *k, unsigned sectors, while (!(b = pick_data_bucket(c, k, write_point, &alloc.key))) { unsigned watermark = write_prio - ? WATERMARK_MOVINGGC - : WATERMARK_NONE; + ? RESERVE_MOVINGGC + : RESERVE_NONE; spin_unlock(&c->data_bucket_lock); @@ -689,7 +718,7 @@ int bch_cache_allocator_init(struct cache *ca) * Then 8 for btree allocations * Then half for the moving garbage collector */ - +#if 0 ca->watermark[WATERMARK_PRIO] = 0; ca->watermark[WATERMARK_METADATA] = prio_buckets(ca); @@ -699,6 +728,6 @@ int bch_cache_allocator_init(struct cache *ca) ca->watermark[WATERMARK_NONE] = ca->free.size / 2 + ca->watermark[WATERMARK_MOVINGGC]; - +#endif return 0; } |