linux-toradex.git/kernel/workqueue.c, branch Colibri_T30_LinuxImageV2.3Beta1_20140804

arm: workqueue: fix get_pool_nr_running()

2012-11-26T14:07:11+00:00

Unfortunately when merging 15 patches NVIDIA missed 3 resp. 4 lines
which failed UP case (e.g. on PXA). The offending commit in question is

9dfdd9ac17ac9955b431cb962df3d0492384ba0e

The list of commits the above should have included is as follows:

974271c485a4d8bb801decc616748f90aafb07ec
bd7bdd43dcb81bb08240b9401b36a104f77dc135: just some comments missing
63d95a9150ee3bbd4117fcd609dee40313b454d9
11ebea50dbc1ade5994b2c838a096078d4c02399
4ce62e9e30cacc26885cab133ad1de358dd79f21: 2 lines missing
3270476a6c0ce322354df8679652f060d66526dc: one line missing
6575820221f7a4dd6eadecf7bf83cdd154335eda
f2d5a0ee06c1813f985bb9386f3ccc0d0315720f
403c821d452c03be4ced571ac91339a9d3631b17
6037315269d62bf967286ae2670fdd6b6acedab9
bc2ae0f5bb2f39e6db06a62f9d353e4601a332a1
25511a477657884d2164f338341fa89652610507
3ce63377305b694f53e7dd0c72907591c5344224
628c78e7ea19d5b70d2b6a59030362168cdbe1ad: just some comments missing
8db25e7891a47e03db6f04344a9c92be16e391bb

workqueue: CPU hotplug keep idle workers

2012-08-13T21:49:54+00:00

This change merges two patchsets. The first set,
containing 6 patches, reimplements WQ_HIGHPRI
to use a seperate worker_pool. gcwq->pools[0]
is used for normal priority work and pools[1]
for high priority.

The second patchset contains 9 patches and
reimplements CPU hotplug to keep idle workers.
Updates workqueue CPU hotplug path to use a
disassociated global_cwq, which runs as an
unbound one (WQ_UNBOUND). While this requires
rebinding idle workers, overall hotplug path
is much simpler.

Original patchset:
http://thread.gmane.org/gmane.linux.kernel/1329164

Bug 978010

Change-Id: Ic66ec8848a8d111b5278e63ef6a410846dfd8fcc
Signed-off-by: Mitch Luban 
Reviewed-on: http://git-master/r/118387
Reviewed-by: Diwakar Tundlam 
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Peter Boonstoppel 
GVS: Gerrit_Virtual_Submit
Reviewed-by: Bharat Nihalani

workqueue: lock cwq access in drain_workqueue

2011-09-15T01:09:38+00:00

Take cwq->gcwq->lock to avoid racing between drain_workqueue checking to
make sure the workqueues are empty and cwq_dec_nr_in_flight decrementing
and then incrementing nr_active when it activates a delayed work.

We discovered this when a corner case in one of our drivers resulted in
us trying to destroy a workqueue in which the remaining work would
always requeue itself again in the same workqueue.  We would hit this
race condition and trip the BUG_ON on workqueue.c:3080.

Signed-off-by: Thomas Tuttle 
Acked-by: Tejun Heo 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge branch 'for-3.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq

2011-07-22T22:07:15+00:00

* 'for-3.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: separate out drain_workqueue() from destroy_workqueue()
  workqueue: remove cancel_rearming_delayed_work[queue]()

Merge branch 'for-2.6.40' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu

2011-05-24T18:53:42+00:00

* 'for-2.6.40' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu: Unify input section names
  percpu: Avoid extra NOP in percpu_cmpxchg16b_double
  percpu: Cast away printk format warning
  percpu: Always align percpu output section to PAGE_SIZE

Fix up fairly trivial conflict in arch/x86/include/asm/percpu.h as per Tejun

workqueue: separate out drain_workqueue() from destroy_workqueue()

2011-05-20T11:54:46+00:00

There are users which want to drain workqueues without destroying it.
Separate out drain functionality from destroy_workqueue() into
drain_workqueue() and make it accessible to workqueue users.

To guarantee forward-progress, only chain queueing is allowed while
drain is in progress.  If a new work item which isn't chained from the
running or pending work items is queued while draining is in progress,
WARN_ON_ONCE() is triggered.

Signed-off-by: Tejun Heo 
Cc: James Bottomley

workqueue: fix deadlock in worker_maybe_bind_and_lock()

2011-04-29T16:08:37+00:00

If a rescuer and stop_machine() bringing down a CPU race with each
other, they may deadlock on non-preemptive kernel.  The CPU won't
accept a new task, so the rescuer can't migrate to the target CPU,
while stop_machine() can't proceed because the rescuer is holding one
of the CPU retrying migration.  GCWQ_DISASSOCIATED is never cleared
and worker_maybe_bind_and_lock() retries indefinitely.

This problem can be reproduced semi reliably while the system is
entering suspend.

 http://thread.gmane.org/gmane.linux.kernel/1122051

A lot of kudos to Thilo-Alexander for reporting this tricky issue and
painstaking testing.

stable: This affects all kernels with cmwq, so all kernels since and
        including v2.6.36 need this fix.

Signed-off-by: Tejun Heo 
Reported-by: Thilo-Alexander Ginkel 
Tested-by: Thilo-Alexander Ginkel 
Cc: stable@kernel.org

percpu: Always align percpu output section to PAGE_SIZE

2011-03-24T17:50:09+00:00

Percpu allocator honors alignment request upto PAGE_SIZE and both the
percpu addresses in the percpu address space and the translated kernel
addresses should be aligned accordingly.  The calculation of the
former depends on the alignment of percpu output section in the kernel
image.

The linker script macros PERCPU_VADDR() and PERCPU() are used to
define this output section and the latter takes @align parameter.
Several architectures are using @align smaller than PAGE_SIZE breaking
percpu memory alignment.

This patch removes @align parameter from PERCPU(), renames it to
PERCPU_SECTION() and makes it always align to PAGE_SIZE.  While at it,
add PCPU_SETUP_BUG_ON() checks such that alignment problems are
reliably detected and remove percpu alignment comment recently added
in workqueue.c as the condition would trigger BUG way before reaching
there.

For um, this patch raises the alignment of percpu area.  As the area
is in .init, there shouldn't be any noticeable difference.

This problem was discovered by David Howells while debugging boot
failure on mn10300.

Signed-off-by: Tejun Heo 
Acked-by: Mike Frysinger 
Cc: uclinux-dist-devel@blackfin.uclinux.org
Cc: David Howells 
Cc: Jeff Dike 
Cc: user-mode-linux-devel@lists.sourceforge.net

kthread: use kthread_create_on_node()

2011-03-23T00:44:01+00:00

ksoftirqd, kworker, migration, and pktgend kthreads can be created with
kthread_create_on_node(), to get proper NUMA affinities for their stack and
task_struct.

Signed-off-by: Eric Dumazet 
Acked-by: David S. Miller 
Reviewed-by: Andi Kleen 
Acked-by: Rusty Russell 
Acked-by: Tejun Heo 
Cc: Tony Luck 
Cc: Fenghua Yu 
Cc: David Howells 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge branch 'for-2.6.39' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq

2011-03-16T15:20:19+00:00

* 'for-2.6.39' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: fix build failure introduced by s/freezeable/freezable/
  workqueue: add system_freezeable_wq
  rds/ib: use system_wq instead of rds_ib_fmr_wq
  net/9p: replace p9_poll_task with a work
  net/9p: use system_wq instead of p9_mux_wq
  xfs: convert to alloc_workqueue()
  reiserfs: make commit_wq use the default concurrency level
  ocfs2: use system_wq instead of ocfs2_quota_wq
  ext4: convert to alloc_workqueue()
  scsi/scsi_tgt_lib: scsi_tgtd isn't used in memory reclaim path
  scsi/be2iscsi,qla2xxx: convert to alloc_workqueue()
  misc/iwmc3200top: use system_wq instead of dedicated workqueues
  i2o: use alloc_workqueue() instead of create_workqueue()
  acpi: kacpi*_wq don't need WQ_MEM_RECLAIM
  fs/aio: aio_wq isn't used in memory reclaim path
  input/tps6507x-ts: use system_wq instead of dedicated workqueue
  cpufreq: use system_wq instead of dedicated workqueues
  wireless/ipw2x00: use system_wq instead of dedicated workqueues
  arm/omap: use system_wq in mailbox
  workqueue: use WQ_MEM_RECLAIM instead of WQ_RESCUER