diff options
| author | Nick Piggin <npiggin@suse.de> | 2009-01-06 14:40:26 -0800 | 
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-01-06 15:59:09 -0800 | 
| commit | 856bf4d717feb8c55d4e2f817b71ebb70cfbc67b (patch) | |
| tree | f44790d9b8f42223955d1866645103ac5f9c68a3 | |
| parent | 38f21977663126fef53f5585e7f1653d8ebe55c4 (diff) | |
| download | olio-linux-3.10-856bf4d717feb8c55d4e2f817b71ebb70cfbc67b.tar.xz olio-linux-3.10-856bf4d717feb8c55d4e2f817b71ebb70cfbc67b.zip  | |
fs: sys_sync fix
s_syncing livelock avoidance was breaking data integrity guarantee of
sys_sync, by allowing sys_sync to skip writing or waiting for superblocks
if there is a concurrent sys_sync happening.
This livelock avoidance is much less important now that we don't have the
get_super_to_sync() call after every sb that we sync.  This was replaced
by __put_super_and_need_restart.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | fs/fs-writeback.c | 20 | ||||
| -rw-r--r-- | include/linux/fs.h | 1 | 
2 files changed, 1 insertions, 20 deletions
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index a9ee474f969..e5eaa62fd17 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -652,18 +652,6 @@ void sync_inodes_sb(struct super_block *sb, int wait)  	sync_sb_inodes(sb, &wbc);  } -/* - * Rather lame livelock avoidance. - */ -static void set_sb_syncing(int val) -{ -	struct super_block *sb; -	spin_lock(&sb_lock); -	list_for_each_entry_reverse(sb, &super_blocks, s_list) -		sb->s_syncing = val; -	spin_unlock(&sb_lock); -} -  /**   * sync_inodes - writes all inodes to disk   * @wait: wait for completion @@ -690,9 +678,6 @@ static void __sync_inodes(int wait)  	spin_lock(&sb_lock);  restart:  	list_for_each_entry(sb, &super_blocks, s_list) { -		if (sb->s_syncing) -			continue; -		sb->s_syncing = 1;  		sb->s_count++;  		spin_unlock(&sb_lock);  		down_read(&sb->s_umount); @@ -710,13 +695,10 @@ restart:  void sync_inodes(int wait)  { -	set_sb_syncing(0);  	__sync_inodes(0); -	if (wait) { -		set_sb_syncing(0); +	if (wait)  		__sync_inodes(1); -	}  }  /** diff --git a/include/linux/fs.h b/include/linux/fs.h index fb59673c60b..d7eba77f666 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1133,7 +1133,6 @@ struct super_block {  	struct rw_semaphore	s_umount;  	struct mutex		s_lock;  	int			s_count; -	int			s_syncing;  	int			s_need_sync_fs;  	atomic_t		s_active;  #ifdef CONFIG_SECURITY  |