From: David Sterba Date: Mon, 26 Feb 2018 15:15:17 +0000 (+0100) Subject: btrfs: replace waitqueue_actvie with cond_wake_up X-Git-Tag: v4.19~584^2~90 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=093258e6ebaf178bb25da514f0d1f744968cc900;p=platform%2Fkernel%2Flinux-rpi.git btrfs: replace waitqueue_actvie with cond_wake_up Use the wrappers and reduce the amount of low-level details about the waitqueue management. Reviewed-by: Nikolay Borisov Signed-off-by: David Sterba --- diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c index 1061575..d3e447b 100644 --- a/fs/btrfs/compression.c +++ b/fs/btrfs/compression.c @@ -990,12 +990,7 @@ static void __free_workspace(int type, struct list_head *workspace, btrfs_compress_op[idx]->free_workspace(workspace); atomic_dec(total_ws); wake: - /* - * Make sure counter is updated before we wake up waiters. - */ - smp_mb(); - if (waitqueue_active(ws_wait)) - wake_up(ws_wait); + cond_wake_up(ws_wait); } static void free_workspace(int type, struct list_head *ws) diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c index a8d492db..fe6caa7 100644 --- a/fs/btrfs/delayed-inode.c +++ b/fs/btrfs/delayed-inode.c @@ -460,13 +460,10 @@ static void finish_one_item(struct btrfs_delayed_root *delayed_root) { int seq = atomic_inc_return(&delayed_root->items_seq); - /* - * atomic_dec_return implies a barrier for waitqueue_active - */ + /* atomic_dec_return implies a barrier */ if ((atomic_dec_return(&delayed_root->items) < - BTRFS_DELAYED_BACKGROUND || seq % BTRFS_DELAYED_BATCH == 0) && - waitqueue_active(&delayed_root->wait)) - wake_up(&delayed_root->wait); + BTRFS_DELAYED_BACKGROUND || seq % BTRFS_DELAYED_BATCH == 0)) + cond_wake_up_nomb(&delayed_root->wait); } static void __btrfs_remove_delayed_item(struct btrfs_delayed_item *delayed_item) diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c index 12f703e..8994628 100644 --- a/fs/btrfs/dev-replace.c +++ b/fs/btrfs/dev-replace.c @@ -1009,9 +1009,9 @@ void btrfs_dev_replace_clear_lock_blocking( ASSERT(atomic_read(&dev_replace->read_locks) > 0); ASSERT(atomic_read(&dev_replace->blocking_readers) > 0); read_lock(&dev_replace->lock); - if (atomic_dec_and_test(&dev_replace->blocking_readers) && - waitqueue_active(&dev_replace->read_lock_wq)) - wake_up(&dev_replace->read_lock_wq); + /* Barrier implied by atomic_dec_and_test */ + if (atomic_dec_and_test(&dev_replace->blocking_readers)) + cond_wake_up_nomb(&dev_replace->read_lock_wq); } void btrfs_bio_counter_inc_noblocked(struct btrfs_fs_info *fs_info) @@ -1022,9 +1022,7 @@ void btrfs_bio_counter_inc_noblocked(struct btrfs_fs_info *fs_info) void btrfs_bio_counter_sub(struct btrfs_fs_info *fs_info, s64 amount) { percpu_counter_sub(&fs_info->bio_counter, amount); - - if (waitqueue_active(&fs_info->replace_wait)) - wake_up(&fs_info->replace_wait); + cond_wake_up_nomb(&fs_info->replace_wait); } void btrfs_bio_counter_inc_blocked(struct btrfs_fs_info *fs_info) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 5be54ce..fa2ed14 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -11081,12 +11081,7 @@ int btrfs_trim_fs(struct btrfs_fs_info *fs_info, struct fstrim_range *range) void btrfs_end_write_no_snapshotting(struct btrfs_root *root) { percpu_counter_dec(&root->subv_writers->counter); - /* - * Make sure counter is updated before we wake up waiters. - */ - smp_mb(); - if (waitqueue_active(&root->subv_writers->wait)) - wake_up(&root->subv_writers->wait); + cond_wake_up(&root->subv_writers->wait); } int btrfs_start_write_no_snapshotting(struct btrfs_root *root) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 6757fe1..563e63f 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -1156,13 +1156,10 @@ static noinline void async_cow_submit(struct btrfs_work *work) nr_pages = (async_cow->end - async_cow->start + PAGE_SIZE) >> PAGE_SHIFT; - /* - * atomic_sub_return implies a barrier for waitqueue_active - */ + /* atomic_sub_return implies a barrier */ if (atomic_sub_return(nr_pages, &fs_info->async_delalloc_pages) < - 5 * SZ_1M && - waitqueue_active(&fs_info->async_submit_wait)) - wake_up(&fs_info->async_submit_wait); + 5 * SZ_1M) + cond_wake_up_nomb(&fs_info->async_submit_wait); if (async_cow->inode) submit_compressed_extents(async_cow->inode, async_cow); diff --git a/fs/btrfs/locking.c b/fs/btrfs/locking.c index e4faefa..1da768e 100644 --- a/fs/btrfs/locking.c +++ b/fs/btrfs/locking.c @@ -66,22 +66,16 @@ void btrfs_clear_lock_blocking_rw(struct extent_buffer *eb, int rw) write_lock(&eb->lock); WARN_ON(atomic_read(&eb->spinning_writers)); atomic_inc(&eb->spinning_writers); - /* - * atomic_dec_and_test implies a barrier for waitqueue_active - */ - if (atomic_dec_and_test(&eb->blocking_writers) && - waitqueue_active(&eb->write_lock_wq)) - wake_up(&eb->write_lock_wq); + /* atomic_dec_and_test implies a barrier */ + if (atomic_dec_and_test(&eb->blocking_writers)) + cond_wake_up_nomb(&eb->write_lock_wq); } else if (rw == BTRFS_READ_LOCK_BLOCKING) { BUG_ON(atomic_read(&eb->blocking_readers) == 0); read_lock(&eb->lock); atomic_inc(&eb->spinning_readers); - /* - * atomic_dec_and_test implies a barrier for waitqueue_active - */ - if (atomic_dec_and_test(&eb->blocking_readers) && - waitqueue_active(&eb->read_lock_wq)) - wake_up(&eb->read_lock_wq); + /* atomic_dec_and_test implies a barrier */ + if (atomic_dec_and_test(&eb->blocking_readers)) + cond_wake_up_nomb(&eb->read_lock_wq); } } @@ -221,12 +215,9 @@ void btrfs_tree_read_unlock_blocking(struct extent_buffer *eb) } btrfs_assert_tree_read_locked(eb); WARN_ON(atomic_read(&eb->blocking_readers) == 0); - /* - * atomic_dec_and_test implies a barrier for waitqueue_active - */ - if (atomic_dec_and_test(&eb->blocking_readers) && - waitqueue_active(&eb->read_lock_wq)) - wake_up(&eb->read_lock_wq); + /* atomic_dec_and_test implies a barrier */ + if (atomic_dec_and_test(&eb->blocking_readers)) + cond_wake_up_nomb(&eb->read_lock_wq); atomic_dec(&eb->read_locks); } @@ -275,12 +266,9 @@ void btrfs_tree_unlock(struct extent_buffer *eb) if (blockers) { WARN_ON(atomic_read(&eb->spinning_writers)); atomic_dec(&eb->blocking_writers); - /* - * Make sure counter is updated before we wake up waiters. - */ + /* Use the lighter barrier after atomic */ smp_mb__after_atomic(); - if (waitqueue_active(&eb->write_lock_wq)) - wake_up(&eb->write_lock_wq); + cond_wake_up_nomb(&eb->write_lock_wq); } else { WARN_ON(atomic_read(&eb->spinning_writers) != 1); atomic_dec(&eb->spinning_writers); diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c index 6db8bb2..2e1a169 100644 --- a/fs/btrfs/ordered-data.c +++ b/fs/btrfs/ordered-data.c @@ -343,11 +343,8 @@ int btrfs_dec_test_first_ordered_pending(struct inode *inode, if (entry->bytes_left == 0) { ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags); - /* - * Implicit memory barrier after test_and_set_bit - */ - if (waitqueue_active(&entry->wait)) - wake_up(&entry->wait); + /* test_and_set_bit implies a barrier */ + cond_wake_up_nomb(&entry->wait); } else { ret = 1; } @@ -410,11 +407,8 @@ have_entry: if (entry->bytes_left == 0) { ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags); - /* - * Implicit memory barrier after test_and_set_bit - */ - if (waitqueue_active(&entry->wait)) - wake_up(&entry->wait); + /* test_and_set_bit implies a barrier */ + cond_wake_up_nomb(&entry->wait); } else { ret = 1; } diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index c944b47..ff841ab 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -877,12 +877,7 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans, atomic_dec(&cur_trans->num_writers); extwriter_counter_dec(cur_trans, trans->type); - /* - * Make sure counter is updated before we wake up waiters. - */ - smp_mb(); - if (waitqueue_active(&cur_trans->writer_wait)) - wake_up(&cur_trans->writer_wait); + cond_wake_up(&cur_trans->writer_wait); btrfs_put_transaction(cur_trans); if (current->journal_info == trans) diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 2009cea..f8220ec 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -222,11 +222,8 @@ int btrfs_pin_log_trans(struct btrfs_root *root) void btrfs_end_log_trans(struct btrfs_root *root) { if (atomic_dec_and_test(&root->log_writers)) { - /* - * Implicit memory barrier after atomic_dec_and_test - */ - if (waitqueue_active(&root->log_writer_wait)) - wake_up(&root->log_writer_wait); + /* atomic_dec_and_test implies a barrier */ + cond_wake_up_nomb(&root->log_writer_wait); } } @@ -2988,11 +2985,8 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans, mutex_lock(&log_root_tree->log_mutex); if (atomic_dec_and_test(&log_root_tree->log_writers)) { - /* - * Implicit memory barrier after atomic_dec_and_test - */ - if (waitqueue_active(&log_root_tree->log_writer_wait)) - wake_up(&log_root_tree->log_writer_wait); + /* atomic_dec_and_test implies a barrier */ + cond_wake_up_nomb(&log_root_tree->log_writer_wait); } if (ret) { @@ -3116,13 +3110,11 @@ out_wake_log_root: mutex_unlock(&log_root_tree->log_mutex); /* - * The barrier before waitqueue_active is needed so all the updates - * above are seen by the woken threads. It might not be necessary, but - * proving that seems to be hard. + * The barrier before waitqueue_active (in cond_wake_up) is needed so + * all the updates above are seen by the woken threads. It might not be + * necessary, but proving that seems to be hard. */ - smp_mb(); - if (waitqueue_active(&log_root_tree->log_commit_wait[index2])) - wake_up(&log_root_tree->log_commit_wait[index2]); + cond_wake_up(&log_root_tree->log_commit_wait[index2]); out: mutex_lock(&root->log_mutex); btrfs_remove_all_log_ctxs(root, index1, ret); @@ -3131,13 +3123,11 @@ out: mutex_unlock(&root->log_mutex); /* - * The barrier before waitqueue_active is needed so all the updates - * above are seen by the woken threads. It might not be necessary, but - * proving that seems to be hard. + * The barrier before waitqueue_active (in cond_wake_up) is needed so + * all the updates above are seen by the woken threads. It might not be + * necessary, but proving that seems to be hard. */ - smp_mb(); - if (waitqueue_active(&root->log_commit_wait[index1])) - wake_up(&root->log_commit_wait[index1]); + cond_wake_up(&root->log_commit_wait[index1]); return ret; }