From: David Sterba <dsterba@suse.com>
Date: Fri, 24 Aug 2018 14:15:51 +0000 (+0200)
Subject: btrfs: use assertion helpers for extent buffer read lock counters
X-Git-Tag: 5.2-smb3~49^2~202
X-Git-Url: http://git.samba.org/samba.git/?p=sfrench%2Fcifs-2.6.git;a=commitdiff_plain;h=5c9c799ab78336a4161b16126952a7e1320a8c77

btrfs: use assertion helpers for extent buffer read lock counters

Use the helpers where open coded. On non-debug builds, the warnings will
not trigger and extent_buffer::read_locks become unused and can be
moved to the appropriate section, saving a few bytes.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
---

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index f010475f74fd..c189b018ed69 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -4678,7 +4678,6 @@ __alloc_extent_buffer(struct btrfs_fs_info *fs_info, u64 start,
 	eb->bflags = 0;
 	rwlock_init(&eb->lock);
 	atomic_set(&eb->write_locks, 0);
-	atomic_set(&eb->read_locks, 0);
 	atomic_set(&eb->blocking_readers, 0);
 	atomic_set(&eb->blocking_writers, 0);
 	eb->lock_nested = 0;
@@ -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);
+	atomic_set(&eb->read_locks, 0);
 #endif
 
 	return eb;
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 89e56df64d6c..41c5d0e9dc75 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -162,7 +162,6 @@ struct extent_buffer {
 
 	/* count of read lock holders on the extent buffer */
 	atomic_t write_locks;
-	atomic_t read_locks;
 	atomic_t blocking_writers;
 	atomic_t blocking_readers;
 	short lock_nested;
@@ -185,6 +184,7 @@ struct extent_buffer {
 #ifdef CONFIG_BTRFS_DEBUG
 	atomic_t spinning_writers;
 	atomic_t spinning_readers;
+	atomic_t read_locks;
 	struct list_head leak_list;
 #endif
 };
diff --git a/fs/btrfs/locking.c b/fs/btrfs/locking.c
index d3bb19835ab4..1088cf322fdd 100644
--- a/fs/btrfs/locking.c
+++ b/fs/btrfs/locking.c
@@ -164,7 +164,7 @@ again:
 			   atomic_read(&eb->blocking_writers) == 0);
 		goto again;
 	}
-	atomic_inc(&eb->read_locks);
+	btrfs_assert_tree_read_locks_get(eb);
 	btrfs_assert_spinning_readers_get(eb);
 }
 
@@ -183,7 +183,7 @@ int btrfs_tree_read_lock_atomic(struct extent_buffer *eb)
 		read_unlock(&eb->lock);
 		return 0;
 	}
-	atomic_inc(&eb->read_locks);
+	btrfs_assert_tree_read_locks_get(eb);
 	btrfs_assert_spinning_readers_get(eb);
 	return 1;
 }
@@ -204,7 +204,7 @@ int btrfs_try_tree_read_lock(struct extent_buffer *eb)
 		read_unlock(&eb->lock);
 		return 0;
 	}
-	atomic_inc(&eb->read_locks);
+	btrfs_assert_tree_read_locks_get(eb);
 	btrfs_assert_spinning_readers_get(eb);
 	return 1;
 }
@@ -248,7 +248,7 @@ void btrfs_tree_read_unlock(struct extent_buffer *eb)
 	}
 	btrfs_assert_tree_read_locked(eb);
 	btrfs_assert_spinning_readers_put(eb);
-	atomic_dec(&eb->read_locks);
+	btrfs_assert_tree_read_locks_put(eb);
 	read_unlock(&eb->lock);
 }
 
@@ -272,7 +272,7 @@ void btrfs_tree_read_unlock_blocking(struct extent_buffer *eb)
 	/* 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);
+	btrfs_assert_tree_read_locks_put(eb);
 }
 
 /*