mirror_zfs/module/spl
Richard Yao a430c11f0b Make taskq_member() use ->journal_info
The ->journal_info pointer in the task_struct is reserved for use by
filesystems and because the kernel can have multiple file systems on the
same stack due to direct reclaim, each filesystem that touches
->journal_info in a callback function will save the value at the start
of its frame and restore it at the end of its frame.  This allows us to
safely use ->journal_info to store a pointer to the taskq's struct in
taskq threads so that ZFS code paths can detect the presence of a taskq.
This could break if the ZFS code were to use taskq_member from the
context of direct reclaim. However, there are no such uses of it in that
manner, so this is safe.

This eliminates an O(N) list traversal under a spinlock with an O(1)
unlocked pointer comparison.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: tuxoko <tuxoko@gmail.com>
Signed-off-by: Tim Chase <tim@chase2k.com>
Closes #500
2015-12-08 13:24:47 -08:00
..
Makefile.in Support parallel build trees (VPATH builds) 2015-07-17 12:53:11 -07:00
spl-atomic.c Refresh links to web site 2013-03-04 19:09:34 -08:00
spl-condvar.c Rename cv_wait_interruptible() to cv_wait_sig() 2015-06-10 16:36:12 -07:00
spl-cred.c Remove credential configure checks. 2014-10-17 15:11:51 -07:00
spl-err.c Retire legacy debugging infrastructure 2014-11-19 10:35:07 -08:00
spl-generic.c Retire spl_module_init()/spl_module_fini() 2015-02-27 13:43:39 -08:00
spl-kmem-cache.c spl-kmem-cache: include linux/prefetch.h for prefetchw() 2015-12-02 12:45:06 -08:00
spl-kmem.c Optimize vmem_alloc() retry path 2015-02-02 10:57:56 -08:00
spl-kobj.c Fix GFP_KERNEL allocations flags 2015-01-21 15:25:19 -08:00
spl-kstat.c Refactor existing code 2015-01-16 13:55:08 -08:00
spl-mutex.c Remove adaptive mutex implementation 2014-10-17 15:07:28 -07:00
spl-proc.c Default to --disable-debug-kmem 2015-07-21 11:47:10 -07:00
spl-rwlock.c Refresh links to web site 2013-03-04 19:09:34 -08:00
spl-taskq.c Make taskq_member() use ->journal_info 2015-12-08 13:24:47 -08:00
spl-thread.c Retire legacy debugging infrastructure 2014-11-19 10:35:07 -08:00
spl-tsd.c Fix cstyle issues in spl-tsd.c 2015-04-24 14:23:07 -07:00
spl-vmem.c Add hooks for disabling direct reclaim 2015-01-16 13:55:09 -08:00
spl-vnode.c Fix race between getf() and areleasef() 2015-12-03 15:44:47 -08:00
spl-xdr.c Retire legacy debugging infrastructure 2014-11-19 10:35:07 -08:00
spl-zlib.c Refactor existing code 2015-01-16 13:55:08 -08:00