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path: root/drivers/md/bcache/alloc.c
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Diffstat (limited to 'drivers/md/bcache/alloc.c')
-rw-r--r--drivers/md/bcache/alloc.c89
1 files changed, 59 insertions, 30 deletions
diff --git a/drivers/md/bcache/alloc.c b/drivers/md/bcache/alloc.c
index 4c9852d92b0a..c0d37d082443 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;
}