diff options
| author | Theodore Ts'o <tytso@mit.edu> | 2017-11-08 22:23:20 -0500 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2017-11-08 22:23:20 -0500 |
| commit | 232530680290ba94ca37852ab10d9556ea28badf (patch) | |
| tree | cf23ba2b6c563adc685f3b9fee830ac7d202546c /fs/ext4/ialloc.c | |
| parent | d77147ff443b255d82c907a632c825b2cc610b10 (diff) | |
| download | linux-232530680290ba94ca37852ab10d9556ea28badf.tar.gz linux-232530680290ba94ca37852ab10d9556ea28badf.tar.bz2 linux-232530680290ba94ca37852ab10d9556ea28badf.zip | |
ext4: improve smp scalability for inode generation
->s_next_generation is protected by s_next_gen_lock but its usage
pattern is very primitive. We don't actually need sequentially
increasing new generation numbers, so let's use prandom_u32() instead.
Reported-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Diffstat (limited to 'fs/ext4/ialloc.c')
| -rw-r--r-- | fs/ext4/ialloc.c | 4 |
1 files changed, 1 insertions, 3 deletions
diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c index ee823022aa34..da79eb5dba40 100644 --- a/fs/ext4/ialloc.c +++ b/fs/ext4/ialloc.c @@ -1138,9 +1138,7 @@ got: inode->i_ino); goto out; } - spin_lock(&sbi->s_next_gen_lock); - inode->i_generation = sbi->s_next_generation++; - spin_unlock(&sbi->s_next_gen_lock); + inode->i_generation = prandom_u32(); /* Precompute checksum seed for inode metadata */ if (ext4_has_metadata_csum(sb)) { |