Commit Graph

323025 Commits

Author SHA1 Message Date
Trond Myklebust
849b286fd0 NFSv4.1: nfs4_proc_layoutreturn must always drop the plh_block_lgets count
Currently it does not do so if the RPC call failed to start. Fix is to
move the decrement of plh_block_lgets into nfs4_layoutreturn_release.

Also remove a redundant test of task->tk_status in nfs4_layoutreturn_done:
if lrp->res.lrs_present is set, then obviously the RPC call succeeded.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:18 -04:00
Trond Myklebust
65857d5768 NFSv4.1: _pnfs_return_layout() shouldn't invalidate the layout on failure
Failure of the layoutreturn allocation fails is not a good reason to
mark the pnfs_layout_hdr as having failed a layoutget or i/o. Just
exit cleanly.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:18 -04:00
Trond Myklebust
e5929f3cff NFSv4.1: Remove the NFS_LAYOUT_RETURNED state
It serves no purpose that the test for whether or not we have valid
layout segments doesn't already serve.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:17 -04:00
Trond Myklebust
173f77e9c5 NFSv4.1: Clear NFS_LAYOUT_BULK_RECALL when the layout segments are freed
Once all the affected layout segments have been freed up, clear the
NFS_LAYOUT_BULK_RECALL flag so that we can reuse the pnfs_layout_hdr

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:17 -04:00
Trond Myklebust
8006bfba36 NFSv4.1: Get rid of the NFS_LAYOUT_DESTROYED state
We already have a mechanism for blocking LAYOUTGET by means of the
plh_block_lgets counter. The only "service" that NFS_LAYOUT_DESTROYED
provides at this point is to block layoutget once the layout segment
list is empty, which basically means that you have to wait until
the pnfs_layout_hdr is destroyed before you can do pNFS on that file
again.

This patch enables the reuse of the pnfs_layout_hdr if the layout
segment list is empty.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:16 -04:00
Trond Myklebust
579342785f NFSv4.1: Remove unused 'default allocation' for pnfs_alloc_layout_hdr()
...and ditto for pnfs_free_layout_hdr()

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:16 -04:00
Trond Myklebust
a9136d4914 NFSv4.1: Get rid of pNFS spin lock debugging asserts...
These are all in static declared functions that are called only once.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:16 -04:00
Trond Myklebust
8f0d27dc5d NFSv4.1: Balance pnfs_layout_hdr refcount in pnfs_layout_(insert|remove)_lseg
Ensure that the reference count for pnfs_layout_hdr reverts to the
original value after a call to pnfs_layout_remove_lseg().

Note that the caller is expected to hold a reference to the struct
pnfs_layout_hdr.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:15 -04:00
Trond Myklebust
905ca191cf NFSv4.1: Clean up pnfs_put_lseg()
There is no longer a need to use pnfs_free_lseg_list(). Just call
pnfs_free_lseg() directly.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:15 -04:00
Trond Myklebust
9c6263819f NFSv4.1: Clean up the removal of pnfs_layout_hdr from the server list
Move the code into pnfs_free_layout_hdr(), and add checks to
get_layout_by_fh_locked to ensure that they don't reference a layout
that is being freed.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:14 -04:00
Trond Myklebust
6622c3ea05 NFSv4.1: Free the pnfs_layout_hdr outside the inode->i_lock
None of the existing pNFS layout drivers seem to require the inode
to be locked while they free the layout header.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:14 -04:00
Trond Myklebust
01d39ce82b NFSv4.1: Remove redundant reference to the pnfs_layout_hdr
Each layout segment already holds a reference to the pnfs_layout_hdr,
so there is no need to hold an extra reference that is released once
the last layout segment is freed.

Ensure that pnfs_find_alloc_layout() always returns a reference
to the pnfs_layout_hdr, which will be matched by the final call to
pnfs_put_layout_hdr() in pnfs_update_layout().

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:13 -04:00
Trond Myklebust
57036a3776 NFSv4.1: Rename the pnfs_put_lseg_common to pnfs_layout_remove_lseg
The latter name is more descriptive of the actual function.
Also rename pnfs_insert_layout to pnfs_layout_insert_lseg.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:13 -04:00
Trond Myklebust
bb346f6397 NFSv4.1: reset the inode MDS threshold counters on layout destruction
Instead of resetting the inode MDS threshold counters when we mark
the layout for destruction, do it as part of freeing the layout.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:12 -04:00
Trond Myklebust
965938b83b NFSv4.1: Get rid of pNFS layout state "NFS_LAYOUT_INVALID"
In all cases where we set NFS_LAYOUT_INVALID, we also set NFS_LAYOUT_DESTROYED.
Furthermore, in all cases where we test for NFS_LAYOUT_INVALID, we should
also be testing for NFS_LAYOUT_DESTROYED, since the latter means that
we hold no valid layout segments.
Ergo the two are redundant.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:12 -04:00
Trond Myklebust
1f7977c136 NFSv4.1: Simplify the pNFS return-on-close code
Confine it to the nfs4_do_close() code.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:12 -04:00
Trond Myklebust
7fdab069b7 NFSv4.1: Fix a race in the pNFS return-on-close code
If we sleep after dropping the inode->i_lock, then we are no longer
atomic with respect to the rpc_wake_up() call in pnfs_layout_remove_lseg().

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:11 -04:00
Trond Myklebust
115ce575cb NFSv4.1: pnfs_layout_io_set_failed must clear invalid lsegs
If pnfs_layout_io_test_failed() authorises a retry of the failed layoutgets,
we should clear the existing layout segments so that we start afresh. Do
this in pnfs_layout_io_set_failed().

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:11 -04:00
Trond Myklebust
3e62121493 NFSv4.1: Don't drop the pnfs_layout_hdr after a layoutget failure
We want to cache the pnfs_layout_hdr after a layoutget or i/o
failure so that pnfs_update_layout() can find it and know when
it is time to retry.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:10 -04:00
Trond Myklebust
830ffb5657 NFSv4.1: Fix a reference leak in pnfs_update_layout
If we exit after the call to pnfs_find_alloc_layout(), we have to ensure
that we put the struct pnfs_layout_hdr.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:10 -04:00
Trond Myklebust
1dfed2737d NFSv4.1: pNFS data servers may be temporarily offline
In cases where the pNFS data server is just temporarily out of service,
we want to mark it as such, and then try again later. Typically that will
be in cases of network connection errors etc.
This patch allows us to mark the devices as being "unavailable" for such
transient errors, and will make them available for retries after a
2 minute timeout period.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:09 -04:00
Trond Myklebust
25c7533357 NFSv4.1: Retry pNFS after a 2 minute timeout
If we had to fall back to read/write through MDS, then assume that we should
retry pNFS after a suitable timeout period.
The following patch sets a timeout of 2 minutes.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:09 -04:00
Trond Myklebust
b9e028fd89 NFSv4.1: Add helpers for setting/reading the I/O fail bit
...and make them local to the pnfs.c file.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:09 -04:00
Trond Myklebust
f86bbcf85d NFSv4.1: Replace dprintk() in pnfs_update_layout with something less buggy
Dereferencing nfsi->layout in order to read plh_flags without holding
a spin lock is bug prone. Furthermore, the dprintk() tells you nothing
about whether or not the call succeeded.
Replace it with something that tells you about whether or not a valid
layout segment was returned for the inode in question.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:08 -04:00
Trond Myklebust
78e4e05c64 NFSv4.1: Replace get_device_info() with filelayout_get_device_info()
Fix the namespace pollution issue.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:08 -04:00
Trond Myklebust
9369a431bc NFSv4.1: Cleanup; add "pnfs_" prefix to put_lseg() and get_lseg()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:07 -04:00
Trond Myklebust
70c3bd2bdf NFSv4.1: Cleanup; add "pnfs_" prefix to get_layout_hdr() and put_layout_hdr()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:07 -04:00
Trond Myklebust
49a85061b0 NFSv4.1: Cleanup add a "pnfs_" prefix to mark_matching_lsegs_invalid
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:06 -04:00
Trond Myklebust
a0b0a6e39b NFS: Clean up the pNFS layoutget interface
Ensure that we do return errors from nfs4_proc_layoutget() and that we
don't mark the layout as having failed if the error was due to a
signal or resource problem on the client side.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:06 -04:00
Trond Myklebust
d19751e7b9 SUNRPC: Get rid of the redundant xprt->shutdown bit field
It is only set after everyone has dereferenced the transport,
and serves no useful purpose: setting it is racy, so all the
socket code, etc still needs to be able to cope with the cases
where they miss reading it.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:05 -04:00
Trond Myklebust
dcfc4f2546 NFS: Write the entire file if a server reboot occurs during fsync()
This is to ensure that we don't clear the NFS_CONTEXT_RESEND_WRITES
flag while there are still writes that haven't been resent.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:05 -04:00
Trond Myklebust
05990d1bf2 NFS: Fix fdatasync/fsync() when confronted with a server reboot
If the server reboots before it can commit the unstable writes to disk,
then nfs_commit_release_pages() will detect this when it compares the
verifier returned by COMMIT to the one returned by WRITE. When this
happens, the client needs to resend those writes in order to guarantee
that they make it to stable storage.

This patch adds a signalling mechanism to notify fsync() that it
needs to retry all writes before it can exit.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:05 -04:00
Trond Myklebust
795a88c968 NFSv4: Convert the nfs4_lock_state->ls_flags to a bit field
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:04 -04:00
Trond Myklebust
2a369153c8 NFS: Clean up helper function nfs4_select_rw_stateid()
We want to be able to pass on the information that the page was not
dirtied under a lock. Instead of adding a flag parameter, do this
by passing a pointer to a 'struct nfs_lock_owner' that may be NULL.

Also reuse this structure in struct nfs_lock_context to carry the
fl_owner_t and pid_t.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:04 -04:00
Trond Myklebust
b3c54de6f8 NFS: Convert nfs_get_lock_context to return an ERR_PTR on failure
We want to be able to distinguish between allocation failures, and
the case where the lock context is not needed (because there are no
locks).

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 16:03:03 -04:00
Trond Myklebust
a11a2bf4de SUNRPC: Optimise away unnecessary data moves in xdr_align_pages
We only have to call xdr_shrink_pagelen() if the remaining RPC
message does not fit in the page buffer length that we supplied
to xdr_align_pages().

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-28 15:58:42 -04:00
Trond Myklebust
13fe4ba1b6 NFSv4.1: decode_getdeviceinfo should check xdr_read_pages() return value
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-26 12:43:10 -04:00
Trond Myklebust
8a9a8b8332 SUNRPC: Fix the return value of xdr_align_pages()
The callers of xdr_align_pages() expect it to return the number of bytes
of actual XDR data remaining in the pages.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-26 12:43:10 -04:00
NeilBrown
62d98c9354 NFS4: avoid underflow when converting error to pointer.
In nfs4_create_sec_client, 'flavor' can hold a negative error
code (returned from nfs4_negotiate_security), even though it
is an 'enum' and hence unsigned.

The code is careful to cast it to an (int) before testing if it
is negative, however it doesn't cast to an (int) before calling
ERR_PTR.

On a machine where "void*" is larger than "int", this results in
the unsigned equivalent of -1 (e.g. 0xffffffff) being converted
to a pointer.  Subsequent code determines that this is not
negative, and so  dereferences it with predictable results.

So: cast 'flavor' to a (signed) int before passing to ERR_PTR.

cc: Benny Halevy <bhalevy@tonian.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-25 10:38:54 -04:00
Wei Yongjun
e8d920c58d NFS: fix the return value check by using IS_ERR
In case of error, the function rpcauth_create() returns ERR_PTR()
and never returns NULL pointer. The NULL test in the return value
check should be replaced with IS_ERR().

dpatch engine is used to auto generated this patch.
(https://github.com/weiyj/dpatch)

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-25 10:36:37 -04:00
Bryan Schumaker
84e28a307e SUNRPC: Set alloc_slot for backchannel tcp ops
f39c1bfb5a (SUNRPC: Fix a UDP transport
regression) introduced the "alloc_slot" function for xprt operations,
but never created one for the backchannel operations.  This patch fixes
a null pointer dereference when mounting NFS over v4.1.

Call Trace:
 [<ffffffffa0207957>] ? xprt_reserve+0x47/0x50 [sunrpc]
 [<ffffffffa02023a4>] call_reserve+0x34/0x60 [sunrpc]
 [<ffffffffa020e280>] __rpc_execute+0x90/0x400 [sunrpc]
 [<ffffffffa020e61a>] rpc_async_schedule+0x2a/0x40 [sunrpc]
 [<ffffffff81073589>] process_one_work+0x139/0x500
 [<ffffffff81070e70>] ? alloc_worker+0x70/0x70
 [<ffffffffa020e5f0>] ? __rpc_execute+0x400/0x400 [sunrpc]
 [<ffffffff81073d1e>] worker_thread+0x15e/0x460
 [<ffffffff8145c839>] ? preempt_schedule+0x49/0x70
 [<ffffffff81073bc0>] ? rescuer_thread+0x230/0x230
 [<ffffffff81079603>] kthread+0x93/0xa0
 [<ffffffff81465d04>] kernel_thread_helper+0x4/0x10
 [<ffffffff81079570>] ? kthread_freezable_should_stop+0x70/0x70
 [<ffffffff81465d00>] ? gs_change+0x13/0x13

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-09-25 10:33:59 -04:00
Trond Myklebust
a519fc7a70 SUNRPC: Ensure that the TCP socket is closed when in CLOSE_WAIT
Instead of doing a shutdown() call, we need to do an actual close().
Ditto if/when the server is sending us junk RPC headers.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: Simon Kirby <sim@hostway.ca>
Cc: stable@vger.kernel.org
2012-09-19 18:16:10 -04:00
Linus Torvalds
c46de2263f Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
 "A small collection of driver fixes/updates and a core fix for 3.6.  It
  contains:

   - Bug fixes for mtip32xx, and support for new hardware (just addition
     of IDs).  They have been queued up for 3.7 for a few weeks as well.

   - rate-limit a failing command error message in block core.

   - A fix for an old cciss bug from Stephen.

   - Prevent overflow of partition count from Alan."

* 'for-linus' of git://git.kernel.dk/linux-block:
  cciss: fix handling of protocol error
  blk: add an upper sanity check on partition adding
  mtip32xx: fix user_buffer check in exec_drive_command
  mtip32xx: Remove dead code
  mtip32xx: Change printk to pr_xxxx
  mtip32xx: Proper reporting of write protect status on big-endian
  mtip32xx: Increase timeout for standby command
  mtip32xx: Handle NCQ commands during the security locked state
  mtip32xx: Add support for new devices
  block: rate-limit the error message from failing commands
2012-09-19 11:04:34 -07:00
Linus Torvalds
077fee0036 SuperH fixes for 3.6-rc7
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Merge tag 'sh-for-linus' of git://github.com/pmundt/linux-sh

Pull SuperH fixes from Paul Mundt.

* tag 'sh-for-linus' of git://github.com/pmundt/linux-sh:
  sh: Fix up TIF_NOTIFY_RESUME sans TIF_SIGPENDING handling.
  sh: pfc: Release spinlock in sh_pfc_gpio_request_enable() error path
  sh: intc: Fix up multi-evt irq association.
2012-09-19 11:03:55 -07:00
Linus Torvalds
cf42d543e5 A quick rpmsg fix from Fernando, fixing two buggy invocations of
dma_free_coherent.
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Merge tag 'rpmsg-3.6-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/rpmsg

Pull rpmsg fix from Ohad Ben-Cohen:
 "A quick rpmsg fix from Fernando, fixing two buggy invocations of
  dma_free_coherent"

* tag 'rpmsg-3.6-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/rpmsg:
  rpmsg: fix dma_free_coherent dev parameter
2012-09-19 11:03:13 -07:00
Linus Torvalds
4b92c17e1d 3 fixes for md in 3.6.
One reverts a recent patch which turns out to not be such a good
 idea.
 Other two fix minor bugs with the new (since 3.3) 'replacement' code
 and have been tagged for -stable.
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Merge tag 'md-3.6-fixes' of git://neil.brown.name/md

Pull md fixes from NeilBrown:
 "3 fixes for md in 3.6.

  One reverts a recent patch which turns out to not be such a good idea.

  Other two fix minor bugs with the new (since 3.3) 'replacement' code
  and have been tagged for -stable."

* tag 'md-3.6-fixes' of git://neil.brown.name/md:
  md: make sure metadata is updated when spares are activated or removed.
  md/raid5: fix calculate of 'degraded' when a replacement becomes active.
  Revert "md/raid5: For odirect-write performance, do not set STRIPE_PREREAD_ACTIVE."
2012-09-19 11:01:38 -07:00
Linus Torvalds
c5c473e29c Merge branch 'for-3.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue / powernow-k8 fix from Tejun Heo:
 "This is the fix for the bug where cpufreq/powernow-k8 was tripping
  BUG_ON() in try_to_wake_up_local() by migrating workqueue worker to a
  different CPU.

    https://bugzilla.kernel.org/show_bug.cgi?id=47301

  As discussed, the fix is now two parts - one to reimplement
  work_on_cpu() so that it doesn't create a new kthread each time and
  the actual fix which makes powernow-k8 use work_on_cpu() instead of
  performing manual migration.

  While pretty late in the merge cycle, both changes are on the safer
  side.  Jiri and I verified two existing users of work_on_cpu() and
  Duncan confirmed that the powernow-k8 fix survived about 18 hours of
  testing."

* 'for-3.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  cpufreq/powernow-k8: workqueue user shouldn't migrate the kworker to another CPU
  workqueue: reimplement work_on_cpu() using system_wq
2012-09-19 11:00:07 -07:00
Tejun Heo
6889125b8b cpufreq/powernow-k8: workqueue user shouldn't migrate the kworker to another CPU
powernowk8_target() runs off a per-cpu work item and if the
cpufreq_policy->cpu is different from the current one, it migrates the
kworker to the target CPU by manipulating current->cpus_allowed.  The
function migrates the kworker back to the original CPU but this is
still broken.  Workqueue concurrency management requires the kworkers
to stay on the same CPU and powernowk8_target() ends up triggerring
BUG_ON(rq != this_rq()) in try_to_wake_up_local() if it contends on
fidvid_mutex and sleeps.

It is unclear why this bug is being reported now.  Duncan says it
appeared to be a regression of 3.6-rc1 and couldn't reproduce it on
3.5.  Bisection seemed to point to 63d95a91 "workqueue: use @pool
instead of @gcwq or @cpu where applicable" which is an non-functional
change.  Given that the reproduce case sometimes took upto days to
trigger, it's easy to be misled while bisecting.  Maybe something made
contention on fidvid_mutex more likely?  I don't know.

This patch fixes the bug by using work_on_cpu() instead if @pol->cpu
isn't the same as the current one.  The code assumes that
cpufreq_policy->cpu is kept online by the caller, which Rafael tells
me is the case.

stable: ed48ece27c ("workqueue: reimplement work_on_cpu() using
        system_wq") should be applied before this; otherwise, the
        behavior could be horrible.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Duncan <1i5t5.duncan@cox.net>
Tested-by: Duncan <1i5t5.duncan@cox.net>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: stable@vger.kernel.org
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=47301
2012-09-19 10:15:01 -07:00
Tejun Heo
ed48ece27c workqueue: reimplement work_on_cpu() using system_wq
The existing work_on_cpu() implementation is hugely inefficient.  It
creates a new kthread, execute that single function and then let the
kthread die on each invocation.

Now that system_wq can handle concurrent executions, there's no
advantage of doing this.  Reimplement work_on_cpu() using system_wq
which makes it simpler and way more efficient.

stable: While this isn't a fix in itself, it's needed to fix a
        workqueue related bug in cpufreq/powernow-k8.  AFAICS, this
        shouldn't break other existing users.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: stable@vger.kernel.org
2012-09-19 10:13:12 -07:00
NeilBrown
6dafab6b13 md: make sure metadata is updated when spares are activated or removed.
It isn't always necessary to update the metadata when spares are
removed as the presence-or-not of a spare isn't really important to
the integrity of an array.
Also activating a spare doesn't always require updating the metadata
as the update on 'recovery-completed' is usually sufficient.

However the introduction of 'replacement' devices have made these
transitions sometimes more important.  For example the 'Replacement'
flag isn't cleared until the original device is removed, so we need
to ensure a metadata update after that 'spare' is removed.

So set MD_CHANGE_DEVS whenever a spare is activated or removed, to
complement the current situation where it is set when a spare is added
or a device is failed (or a number of other less common situations).

This is suitable for -stable as out-of-data metadata could lead
to data corruption.
This is only relevant for 3.3 and later 9when 'replacement' as
introduced.

Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
2012-09-19 12:54:22 +10:00