linux/kernel/workqueue.c, branch v2.6.39

workqueue: fix deadlock in worker_maybe_bind_and_lock()

2011-04-29T16:08:37Z

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

kthread: use kthread_create_on_node()

2011-03-23T00:44:01Z

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

2011-03-16T15:20:19Z

* '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

debugobjects: Add hint for better object identification

2011-03-08T15:10:38Z

In complex subsystems like mac80211 structures can contain several timers and work structs, so identifying a specific instance from the call trace and object type output of debugobjects can be hard. Allow the subsystems which support debugobjects to provide a hint function. This function returns a pointer to a kernel address (preferrably the objects callback function) which is printed along with the debugobjects type. Add hint methods for timer_list, work_struct and hrtimer. [ tglx: Massaged changelog, made it compile ] Signed-off-by: Stanislaw Gruszka LKML-Reference: <20110307085809.GA9334@redhat.com> Signed-off-by: Thomas Gleixner

workqueue: fix build failure introduced by s/freezeable/freezable/

2011-02-21T09:07:23Z

wq:fixes-2.6.38 does s/WQ_FREEZEABLE/WQ_FREEZABLE and wq:for-2.6.39 adds new usage of the flag. The combination of the two creates a build failure after merge. Fix it by renaming all freezeables to freezables. Signed-off-by: Tejun Heo Reported-by: Stephen Rothwell

Merge branch 'master' into for-2.6.39

2011-02-21T08:43:56Z

workqueue: make sure MAYDAY_INITIAL_TIMEOUT is at least 2 jiffies long

2011-02-16T17:10:19Z

MAYDAY_INITIAL_TIMEOUT is defined as HZ / 100 and depending on configuration may end up 0 or 1. Even when it's 1, depending on when the mayday timer is added in the current jiffy interval, it may expire way before a jiffy has passed. Make sure MAYDAY_INITIAL_TIMEOUT is at least two to guarantee that at least a full jiffy has passed before calling rescuers. Signed-off-by: Tejun Heo Reported-by: Ray Jui Cc: stable@kernel.org

workqueue, freezer: unify spelling of 'freeze' + 'able' to 'freezable'

2011-02-16T16:48:59Z

There are two spellings in use for 'freeze' + 'able' - 'freezable' and 'freezeable'. The former is the more prominent one. The latter is mostly used by workqueue and in a few other odd places. Unify the spelling to 'freezable'. Signed-off-by: Tejun Heo Reported-by: Alan Stern Acked-by: "Rafael J. Wysocki" Acked-by: Greg Kroah-Hartman Acked-by: Dmitry Torokhov Cc: David Woodhouse Cc: Alex Dubov Cc: "David S. Miller" Cc: Steven Whitehouse

workqueue: wake up a worker when a rescuer is leaving a gcwq

2011-02-14T13:04:46Z

After executing the matching works, a rescuer leaves the gcwq whether there are more pending works or not. This may decrease the concurrency level to zero and stall execution until a new work item is queued on the gcwq. Make rescuer wake up a regular worker when it leaves a gcwq if there are more works to execute, so that execution isn't stalled. Signed-off-by: Tejun Heo Reported-by: Ray Jui Cc: stable@kernel.org

workqueue: add system_freezeable_wq

2011-02-09T08:37:49Z

Add system wide freezeable workqueue. Signed-off-by: Tejun Heo Acked-by: Dmitry Torokhov Cc: "Rafael J. Wysocki"