diff options
Diffstat (limited to 'drivers/md/bcache/writeback.c')
-rw-r--r-- | drivers/md/bcache/writeback.c | 133 |
1 files changed, 59 insertions, 74 deletions
diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c index 9ee0005874cd..3f0ff3aab6f2 100644 --- a/drivers/md/bcache/writeback.c +++ b/drivers/md/bcache/writeback.c @@ -235,19 +235,27 @@ static void update_writeback_rate(struct work_struct *work) return; } - if (atomic_read(&dc->has_dirty) && dc->writeback_percent) { - /* - * If the whole cache set is idle, set_at_max_writeback_rate() - * will set writeback rate to a max number. Then it is - * unncessary to update writeback rate for an idle cache set - * in maximum writeback rate number(s). - */ - if (!set_at_max_writeback_rate(c, dc)) { - down_read(&dc->writeback_lock); + /* + * If the whole cache set is idle, set_at_max_writeback_rate() + * will set writeback rate to a max number. Then it is + * unncessary to update writeback rate for an idle cache set + * in maximum writeback rate number(s). + */ + if (atomic_read(&dc->has_dirty) && dc->writeback_percent && + !set_at_max_writeback_rate(c, dc)) { + do { + if (!down_read_trylock((&dc->writeback_lock))) { + dc->rate_update_retry++; + if (dc->rate_update_retry <= + BCH_WBRATE_UPDATE_MAX_SKIPS) + break; + down_read(&dc->writeback_lock); + dc->rate_update_retry = 0; + } __update_writeback_rate(dc); update_gc_after_writeback(c); up_read(&dc->writeback_lock); - } + } while (0); } @@ -805,13 +813,11 @@ static int bch_writeback_thread(void *arg) /* Init */ #define INIT_KEYS_EACH_TIME 500000 -#define INIT_KEYS_SLEEP_MS 100 struct sectors_dirty_init { struct btree_op op; unsigned int inode; size_t count; - struct bkey start; }; static int sectors_dirty_init_fn(struct btree_op *_op, struct btree *b, @@ -827,11 +833,8 @@ static int sectors_dirty_init_fn(struct btree_op *_op, struct btree *b, KEY_START(k), KEY_SIZE(k)); op->count++; - if (atomic_read(&b->c->search_inflight) && - !(op->count % INIT_KEYS_EACH_TIME)) { - bkey_copy_key(&op->start, k); - return -EAGAIN; - } + if (!(op->count % INIT_KEYS_EACH_TIME)) + cond_resched(); return MAP_CONTINUE; } @@ -846,24 +849,16 @@ static int bch_root_node_dirty_init(struct cache_set *c, bch_btree_op_init(&op.op, -1); op.inode = d->id; op.count = 0; - op.start = KEY(op.inode, 0, 0); - - do { - ret = bcache_btree(map_keys_recurse, - k, - c->root, - &op.op, - &op.start, - sectors_dirty_init_fn, - 0); - if (ret == -EAGAIN) - schedule_timeout_interruptible( - msecs_to_jiffies(INIT_KEYS_SLEEP_MS)); - else if (ret < 0) { - pr_warn("sectors dirty init failed, ret=%d!\n", ret); - break; - } - } while (ret == -EAGAIN); + + ret = bcache_btree(map_keys_recurse, + k, + c->root, + &op.op, + &KEY(op.inode, 0, 0), + sectors_dirty_init_fn, + 0); + if (ret < 0) + pr_warn("sectors dirty init failed, ret=%d!\n", ret); return ret; } @@ -907,7 +902,6 @@ static int bch_dirty_init_thread(void *arg) goto out; } skip_nr--; - cond_resched(); } if (p) { @@ -917,7 +911,6 @@ static int bch_dirty_init_thread(void *arg) p = NULL; prev_idx = cur_idx; - cond_resched(); } out: @@ -948,67 +941,56 @@ void bch_sectors_dirty_init(struct bcache_device *d) struct btree_iter iter; struct sectors_dirty_init op; struct cache_set *c = d->c; - struct bch_dirty_init_state *state; - char name[32]; + struct bch_dirty_init_state state; /* Just count root keys if no leaf node */ + rw_lock(0, c->root, c->root->level); if (c->root->level == 0) { bch_btree_op_init(&op.op, -1); op.inode = d->id; op.count = 0; - op.start = KEY(op.inode, 0, 0); for_each_key_filter(&c->root->keys, k, &iter, bch_ptr_invalid) sectors_dirty_init_fn(&op.op, c->root, k); - return; - } - state = kzalloc(sizeof(struct bch_dirty_init_state), GFP_KERNEL); - if (!state) { - pr_warn("sectors dirty init failed: cannot allocate memory\n"); + rw_unlock(0, c->root); return; } - state->c = c; - state->d = d; - state->total_threads = bch_btre_dirty_init_thread_nr(); - state->key_idx = 0; - spin_lock_init(&state->idx_lock); - atomic_set(&state->started, 0); - atomic_set(&state->enough, 0); - init_waitqueue_head(&state->wait); - - for (i = 0; i < state->total_threads; i++) { - /* Fetch latest state->enough earlier */ + memset(&state, 0, sizeof(struct bch_dirty_init_state)); + state.c = c; + state.d = d; + state.total_threads = bch_btre_dirty_init_thread_nr(); + state.key_idx = 0; + spin_lock_init(&state.idx_lock); + atomic_set(&state.started, 0); + atomic_set(&state.enough, 0); + init_waitqueue_head(&state.wait); + + for (i = 0; i < state.total_threads; i++) { + /* Fetch latest state.enough earlier */ smp_mb__before_atomic(); - if (atomic_read(&state->enough)) + if (atomic_read(&state.enough)) break; - state->infos[i].state = state; - atomic_inc(&state->started); - snprintf(name, sizeof(name), "bch_dirty_init[%d]", i); - - state->infos[i].thread = - kthread_run(bch_dirty_init_thread, - &state->infos[i], - name); - if (IS_ERR(state->infos[i].thread)) { + state.infos[i].state = &state; + state.infos[i].thread = + kthread_run(bch_dirty_init_thread, &state.infos[i], + "bch_dirtcnt[%d]", i); + if (IS_ERR(state.infos[i].thread)) { pr_err("fails to run thread bch_dirty_init[%d]\n", i); for (--i; i >= 0; i--) - kthread_stop(state->infos[i].thread); + kthread_stop(state.infos[i].thread); goto out; } + atomic_inc(&state.started); } - /* - * Must wait for all threads to stop. - */ - wait_event_interruptible(state->wait, - atomic_read(&state->started) == 0); - out: - kfree(state); + /* Must wait for all threads to stop. */ + wait_event(state.wait, atomic_read(&state.started) == 0); + rw_unlock(0, c->root); } void bch_cached_dev_writeback_init(struct cached_dev *dc) @@ -1032,6 +1014,9 @@ void bch_cached_dev_writeback_init(struct cached_dev *dc) dc->writeback_rate_fp_term_high = 1000; dc->writeback_rate_i_term_inverse = 10000; + /* For dc->writeback_lock contention in update_writeback_rate() */ + dc->rate_update_retry = 0; + WARN_ON(test_and_clear_bit(BCACHE_DEV_WB_RUNNING, &dc->disk.flags)); INIT_DELAYED_WORK(&dc->writeback_rate_update, update_writeback_rate); } |