linux/fs/xfs/linux-2.6
Dave Chinner e176579e70 xfs: lockless per-ag lookups
When we start taking a reference to the per-ag for every cached
buffer in the system, kernel lockstat profiling on an 8-way create
workload shows the mp->m_perag_lock has higher acquisition rates
than the inode lock and has significantly more contention. That is,
it becomes the highest contended lock in the system.

The perag lookup is trivial to convert to lock-less RCU lookups
because perag structures never go away. Hence the only thing we need
to protect against is tree structure changes during a grow. This can
be done simply by replacing the locking in xfs_perag_get() with RCU
read locking. This removes the mp->m_perag_lock completely from this
path.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
2010-10-18 15:07:44 -05:00
..
kmem.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
kmem.h xfs: replace KM_LARGE with explicit vmalloc use 2010-01-21 13:44:56 -06:00
mrlock.h
sv.h
time.h
xfs_acl.c xfs: split xfs_itrace_entry 2010-07-26 13:16:44 -05:00
xfs_aops.c xfs: do not discard page cache data on EAGAIN 2010-08-24 11:47:51 +10:00
xfs_aops.h direct-io: move aio_complete into ->end_io 2010-07-26 16:09:02 -05:00
xfs_buf.c xfs: log IO completion workqueue is a high priority queue 2010-09-10 10:16:54 -05:00
xfs_buf.h xfs: improve buffer cache hash scalability 2010-09-02 15:14:38 +10:00
xfs_cred.h
xfs_export.c xfs: remove xfs_iput_new 2010-07-26 13:16:44 -05:00
xfs_export.h
xfs_file.c xfs: remove a dmapi leftover 2010-07-26 13:16:47 -05:00
xfs_fs_subr.c xfs: use range primitives for xfs page cache operations 2010-10-18 15:07:24 -05:00
xfs_globals.c
xfs_globals.h
xfs_ioctl32.c xfs: Introduce XFS_IOC_ZERO_RANGE 2010-10-18 15:07:25 -05:00
xfs_ioctl32.h
xfs_ioctl.c xfs: Introduce XFS_IOC_ZERO_RANGE 2010-10-18 15:07:25 -05:00
xfs_ioctl.h xfs: convert attr to use unsigned names 2010-01-20 10:47:48 +11:00
xfs_iops.c xfs: Make fiemap work with sparse files 2010-09-03 09:02:11 -05:00
xfs_iops.h
xfs_linux.h xfs: new truncate sequence 2010-08-09 16:47:42 -04:00
xfs_quotaops.c Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6 2010-08-07 12:57:07 -07:00
xfs_stats.c xfs: switch to seq_file 2009-09-15 12:29:24 -05:00
xfs_stats.h
xfs_super.c xfs: dummy transactions should not dirty VFS state 2010-08-24 11:46:31 +10:00
xfs_super.h xfs: drop dmapi hooks 2010-07-26 13:16:33 -05:00
xfs_sync.c xfs: lockless per-ag lookups 2010-10-18 15:07:44 -05:00
xfs_sync.h xfs: remove explicit xfs_sync_data/xfs_sync_attr calls on umount 2010-07-26 13:16:42 -05:00
xfs_sysctl.c sysctl: Drop & in front of every proc_handler. 2009-11-18 08:37:40 -08:00
xfs_sysctl.h
xfs_trace.c xfs: remove unneeded #include statements 2010-07-26 13:16:33 -05:00
xfs_trace.h convert remaining ->clear_inode() to ->evict_inode() 2010-08-09 16:48:37 -04:00
xfs_version.h
xfs_vnode.h xfs: event tracing support 2009-12-14 23:08:16 -06:00
xfs_xattr.c xfs: constify xattr_handler 2010-05-21 18:31:19 -04:00