Tejun Heo 5456088635 workqueue: apply __WQ_ORDERED to create_singlethread_workqueue() ... commit e09c2c2954 upstream. create_singlethread_workqueue() is a compat interface for single threaded workqueue which maps to ordered workqueue w/ rescuer in the current implementation. create_singlethread_workqueue() currently implemented by invoking alloc_workqueue() w/ appropriate parameters. 8719dceae2 ("workqueue: reject adjusting max_active or applying attrs to ordered workqueues") introduced __WQ_ORDERED to protect ordered workqueues against dynamic attribute changes which can break ordering guarantees but forgot to apply it to create_singlethread_workqueue(). This in itself is okay as nobody currently uses dynamic attribute change on workqueues created with create_singlethread_workqueue(). However, 4c16bd327c ("workqueue: implement NUMA affinity for unbound workqueues") broke singlethreaded guarantee for ordered workqueues through allocating a separate pool_workqueue on each NUMA node by default. A later change 8a2b753844 ("workqueue: fix ordered workqueues in NUMA setups") fixed it by allocating only one global pool_workqueue if __WQ_ORDERED is set. Combined, the __WQ_ORDERED omission in create_singlethread_workqueue() became critical breaking its single threadedness and ordering guarantee. Let's make create_singlethread_workqueue() wrap alloc_ordered_workqueue() instead so that it inherits __WQ_ORDERED and can implicitly track future ordered_workqueue changes. v2: I missed that __WQ_ORDERED now protects against pwq splitting across NUMA nodes and incorrectly described the patch as a nice-to-have fix to protect against future dynamic attribute usages. Oleg pointed out that this is actually a critical breakage due to 8a2b753844 ("workqueue: fix ordered workqueues in NUMA setups"). Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Mike Anderson <mike.anderson@us.ibm.com> Cc: Oleg Nesterov <onestero@redhat.com> Cc: Gustavo Luiz Duarte <gduarte@redhat.com> Cc: Tomas Henzl <thenzl@redhat.com> Fixes: 4c16bd327c ("workqueue: implement NUMA affinity for unbound workqueues") Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2014-10-05 14:54:12 -07:00
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acpi	ACPI / hotplug: Fix conflicted PCI bridge notify handlers	2013-12-04 10:57:04 -08:00
asm-generic	mm: use paravirt friendly ops for NUMA hinting ptes	2014-05-30 21:52:12 -07:00
clocksource	clocksource: arch_timer: use virtual counters	2014-01-09 12:24:26 -08:00
crypto	crypto: scatterwalk - Use sg_chain_ptr on chain entries	2013-12-11 22:36:29 -08:00
drm	drm/radeon: add additional SI pci ids	2014-09-05 16:28:36 -07:00
dt-bindings
keys
linux	workqueue: apply __WQ_ORDERED to create_singlethread_workqueue()	2014-10-05 14:54:12 -07:00
math-emu
media	media: v4l2: added missing mutex.h include to v4l2-ctrls.h	2013-09-26 17:18:26 -07:00
memory
misc
net	ip: make IP identifiers less predictable	2014-08-14 09:24:15 +08:00
pcmcia
ras
rdma
rxrpc
scsi	scsi: fix our current target reap infrastructure	2014-05-30 21:52:11 -07:00
sound	ALSA: control: Protect user controls against concurrent access	2014-06-26 15:12:43 -04:00
target	target: Report correct response length for some commands	2014-06-30 20:09:45 -07:00
trace	tracing: Fix syscall_*regfunc() vs copy_process() race	2014-07-06 18:54:16 -07:00
uapi	ALSA: compress: Cancel the optimization of compiler and fix the size of struct for all platform.	2014-06-26 15:12:41 -04:00
video	Merge branch 'fbdev-3.10-fixes' of git://gitorious.org/linux-omap-dss2/linux into linux-fbdev/for-3.10-fixes	2013-05-29 17:00:34 +08:00
xen	xenbus: delay xenbus frontend resume if xenstored is not running	2013-05-29 09:04:19 -04:00
Kbuild