From afd495a8264fb25cef49834b5c3559b8aaa612ee Mon Sep 17 00:00:00 2001 From: David Sterba Date: Fri, 24 Aug 2018 15:57:38 +0200 Subject: [PATCH] btrfs: use assertion helpers for spinning readers Use the helpers where open coded. On non-debug builds, the warnings will not trigger and extent_buffer::spining_readers become unused and can be moved to the appropriate section, saving a few bytes. Reviewed-by: Nikolay Borisov Reviewed-by: Johannes Thumshirn Signed-off-by: David Sterba --- fs/btrfs/extent_io.c | 2 +- fs/btrfs/extent_io.h | 2 +- fs/btrfs/locking.c | 14 ++++++-------- 3 files changed, 8 insertions(+), 10 deletions(-) diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index fc0451c3e24e..f010475f74fd 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -4681,7 +4681,6 @@ __alloc_extent_buffer(struct btrfs_fs_info *fs_info, u64 start, atomic_set(&eb->read_locks, 0); atomic_set(&eb->blocking_readers, 0); atomic_set(&eb->blocking_writers, 0); - atomic_set(&eb->spinning_readers, 0); eb->lock_nested = 0; init_waitqueue_head(&eb->write_lock_wq); init_waitqueue_head(&eb->read_lock_wq); @@ -4701,6 +4700,7 @@ __alloc_extent_buffer(struct btrfs_fs_info *fs_info, u64 start, #ifdef CONFIG_BTRFS_DEBUG atomic_set(&eb->spinning_writers, 0); + atomic_set(&eb->spinning_readers, 0); #endif return eb; diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h index 3577ef33bc36..89e56df64d6c 100644 --- a/fs/btrfs/extent_io.h +++ b/fs/btrfs/extent_io.h @@ -165,7 +165,6 @@ struct extent_buffer { atomic_t read_locks; atomic_t blocking_writers; atomic_t blocking_readers; - atomic_t spinning_readers; short lock_nested; /* >= 0 if eb belongs to a log tree, -1 otherwise */ short log_index; @@ -185,6 +184,7 @@ struct extent_buffer { struct page *pages[INLINE_EXTENT_BUFFER_PAGES]; #ifdef CONFIG_BTRFS_DEBUG atomic_t spinning_writers; + atomic_t spinning_readers; struct list_head leak_list; #endif }; diff --git a/fs/btrfs/locking.c b/fs/btrfs/locking.c index 2dd3ae524aa3..47bcd288977d 100644 --- a/fs/btrfs/locking.c +++ b/fs/btrfs/locking.c @@ -62,8 +62,7 @@ void btrfs_set_lock_blocking_read(struct extent_buffer *eb) return; btrfs_assert_tree_read_locked(eb); atomic_inc(&eb->blocking_readers); - WARN_ON(atomic_read(&eb->spinning_readers) == 0); - atomic_dec(&eb->spinning_readers); + btrfs_assert_spinning_readers_put(eb); read_unlock(&eb->lock); } @@ -95,7 +94,7 @@ void btrfs_clear_lock_blocking_read(struct extent_buffer *eb) return; BUG_ON(atomic_read(&eb->blocking_readers) == 0); read_lock(&eb->lock); - atomic_inc(&eb->spinning_readers); + btrfs_assert_spinning_readers_get(eb); /* atomic_dec_and_test implies a barrier */ if (atomic_dec_and_test(&eb->blocking_readers)) cond_wake_up_nomb(&eb->read_lock_wq); @@ -150,7 +149,7 @@ again: goto again; } atomic_inc(&eb->read_locks); - atomic_inc(&eb->spinning_readers); + btrfs_assert_spinning_readers_get(eb); } /* @@ -169,7 +168,7 @@ int btrfs_tree_read_lock_atomic(struct extent_buffer *eb) return 0; } atomic_inc(&eb->read_locks); - atomic_inc(&eb->spinning_readers); + btrfs_assert_spinning_readers_get(eb); return 1; } @@ -190,7 +189,7 @@ int btrfs_try_tree_read_lock(struct extent_buffer *eb) return 0; } atomic_inc(&eb->read_locks); - atomic_inc(&eb->spinning_readers); + btrfs_assert_spinning_readers_get(eb); return 1; } @@ -232,8 +231,7 @@ void btrfs_tree_read_unlock(struct extent_buffer *eb) return; } btrfs_assert_tree_read_locked(eb); - WARN_ON(atomic_read(&eb->spinning_readers) == 0); - atomic_dec(&eb->spinning_readers); + btrfs_assert_spinning_readers_put(eb); atomic_dec(&eb->read_locks); read_unlock(&eb->lock); } -- 2.30.2