diff options
| author | George Wang <xuw2015@gmail.com> | 2015-05-29 07:39:34 +1000 |
|---|---|---|
| committer | Dave Chinner <david@fromorbit.com> | 2015-05-29 07:39:34 +1000 |
| commit | 74f9ce1cf2830b94e189f4e99678dbf19aa3bc90 (patch) | |
| tree | fda31de04c0e47f9ddfe5b9ef4d0a17106233491 | |
| parent | 5ebe6afaf0057ac3eaeb98defd5456894b446d22 (diff) | |
| download | op-kernel-dev-74f9ce1cf2830b94e189f4e99678dbf19aa3bc90.zip op-kernel-dev-74f9ce1cf2830b94e189f4e99678dbf19aa3bc90.tar.gz | |
xfs: use percpu_counter_read_positive for mp->m_icount
Function percpu_counter_read just return the current counter, which can be
negative. This will cause the checking of "allocated inode
counts <= m_maxicount" false positive. Use percpu_counter_read_positive can
solve this problem, and be consistent with the purpose to introduce percpu
mechanism to xfs.
Signed-off-by: George Wang <xuw2015@gmail.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
| -rw-r--r-- | fs/xfs/libxfs/xfs_ialloc.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/fs/xfs/libxfs/xfs_ialloc.c b/fs/xfs/libxfs/xfs_ialloc.c index 07349a1..1c9e755 100644 --- a/fs/xfs/libxfs/xfs_ialloc.c +++ b/fs/xfs/libxfs/xfs_ialloc.c @@ -376,7 +376,7 @@ xfs_ialloc_ag_alloc( */ newlen = args.mp->m_ialloc_inos; if (args.mp->m_maxicount && - percpu_counter_read(&args.mp->m_icount) + newlen > + percpu_counter_read_positive(&args.mp->m_icount) + newlen > args.mp->m_maxicount) return -ENOSPC; args.minlen = args.maxlen = args.mp->m_ialloc_blks; @@ -1339,10 +1339,13 @@ xfs_dialloc( * If we have already hit the ceiling of inode blocks then clear * okalloc so we scan all available agi structures for a free * inode. + * + * Read rough value of mp->m_icount by percpu_counter_read_positive, + * which will sacrifice the preciseness but improve the performance. */ if (mp->m_maxicount && - percpu_counter_read(&mp->m_icount) + mp->m_ialloc_inos > - mp->m_maxicount) { + percpu_counter_read_positive(&mp->m_icount) + mp->m_ialloc_inos + > mp->m_maxicount) { noroom = 1; okalloc = 0; } |
