Tejun Heo e93ad19d05 cpuset: make mm migration asynchronous ... If "cpuset.memory_migrate" is set, when a process is moved from one cpuset to another with a different memory node mask, pages in used by the process are migrated to the new set of nodes. This was performed synchronously in the ->attach() callback, which is synchronized against process management. Recently, the synchronization was changed from per-process rwsem to global percpu rwsem for simplicity and optimization. Combined with the synchronous mm migration, this led to deadlocks because mm migration could schedule a work item which may in turn try to create a new worker blocking on the process management lock held from cgroup process migration path. This heavy an operation shouldn't be performed synchronously from that deep inside cgroup migration in the first place. This patch punts the actual migration to an ordered workqueue and updates cgroup process migration and cpuset config update paths to flush the workqueue after all locks are released. This way, the operations still seem synchronous to userland without entangling mm migration with process management synchronization. CPU hotplug can also invoke mm migration but there's no reason for it to wait for mm migrations and thus doesn't synchronize against their completions. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-and-tested-by: Christian Borntraeger <borntraeger@de.ibm.com> Cc: stable@vger.kernel.org # v4.4+		2016-01-22 10:22:46 -05:00
..
bpf	net: bpf: reject invalid shifts	2016-01-12 17:06:53 -05:00
configs
debug	module: use a structure to encapsulate layout.	2015-12-04 22:46:25 +01:00
events	ptrace: use fsuid, fsgid, effective creds for fs access checks	2016-01-20 17:09:18 -08:00
gcov	gcov: use within_module() helper.	2015-12-04 22:46:25 +01:00
irq	PCI changes for the v4.5 merge window:	2016-01-21 11:52:16 -08:00
livepatch	livepatch: Cleanup module page permission changes	2015-12-04 22:51:07 +01:00
locking	Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2016-01-11 14:18:38 -08:00
power	PM / sleep: Add support for read-only sysfs attributes	2016-01-04 22:28:59 +01:00
printk	kernel: printk: specify alignment for struct printk_log	2016-01-20 17:09:18 -08:00
rcu	Merge branches 'doc.2015.12.05a', 'exp.2015.12.07a', 'fixes.2015.12.07a', 'list.2015.12.04b' and 'torture.2015.12.05a' into HEAD	2015-12-07 17:02:54 -08:00
sched	More power management and ACPI updates for v4.5-rc1	2016-01-20 19:06:49 -08:00
time	Merge branch 'pm-cpuidle'	2016-01-21 00:43:21 +01:00
trace	Not much new with tracing for this release. Mostly just clean ups and	2016-01-12 20:04:15 -08:00
.gitignore	certs: add .gitignore to stop git nagging about x509_certificate_list	2015-10-21 15:18:35 +01:00
acct.c
async.c	async: export current_is_async()	2015-11-19 17:51:48 +01:00
audit.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security	2016-01-17 19:13:15 -08:00
audit.h	security: Make inode argument of inode_getsecid non-const	2015-12-24 11:09:39 -05:00
audit_fsnotify.c
audit_tree.c	audit: audit_tree_match can be boolean	2015-11-04 08:23:51 -05:00
audit_watch.c
auditfilter.c	audit: fix comment block whitespace	2015-11-04 08:23:51 -05:00
auditsc.c	security: Make inode argument of inode_getsecid non-const	2015-12-24 11:09:39 -05:00
backtracetest.c
bounds.c
capability.c
cgroup.c	cpuset: make mm migration asynchronous	2016-01-22 10:22:46 -05:00
cgroup_freezer.c	cgroup: kill cgrp_ss_priv[CGROUP_CANFORK_COUNT] and friends	2015-12-03 10:24:08 -05:00
cgroup_pids.c	cgroup_pids: fix a typo.	2015-12-14 14:54:37 -05:00
compat.c
configs.c
context_tracking.c	context_tracking: Switch to new static_branch API	2015-11-24 09:56:43 +01:00
cpu.c	kernel/cpu.c: make set_cpu_* static inlines	2016-01-20 17:09:18 -08:00
cpu_pm.c
cpuset.c	cpuset: make mm migration asynchronous	2016-01-22 10:22:46 -05:00
crash_dump.c
cred.c	kmemcg: account certain kmem allocations to memcg	2016-01-14 16:00:49 -08:00
delayacct.c	kmemcg: account certain kmem allocations to memcg	2016-01-14 16:00:49 -08:00
dma.c
elfcore.c
exec_domain.c
exit.c	exit: remove unneeded declaration of exit_mm()	2016-01-20 17:09:18 -08:00
extable.c
fork.c	mm: rework virtual memory accounting	2016-01-14 16:00:49 -08:00
freezer.c
futex.c	ptrace: use fsuid, fsgid, effective creds for fs access checks	2016-01-20 17:09:18 -08:00
futex_compat.c	ptrace: use fsuid, fsgid, effective creds for fs access checks	2016-01-20 17:09:18 -08:00
groups.c
hung_task.c
irq_work.c	treewide: Remove old email address	2015-11-23 09:44:58 +01:00
jump_label.c	treewide: Remove old email address	2015-11-23 09:44:58 +01:00
kallsyms.c
kcmp.c	ptrace: use fsuid, fsgid, effective creds for fs access checks	2016-01-20 17:09:18 -08:00
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kexec.c	kexec: set KEXEC_TYPE_CRASH before sanity_check_segment_list()	2016-01-20 17:09:18 -08:00
kexec_core.c	kernel/kexec_core.c: use list_for_each_entry_safe in kimage_free_page_list	2016-01-20 17:09:18 -08:00
kexec_file.c	kexec: move some memembers and definitions within the scope of CONFIG_KEXEC_FILE	2016-01-20 17:09:18 -08:00
kexec_internal.h	kexec: move some memembers and definitions within the scope of CONFIG_KEXEC_FILE	2016-01-20 17:09:18 -08:00
kmod.c	kmod: don't run async usermode helper as a child of kworker thread	2015-10-23 17:55:10 +09:00
kprobes.c
ksysfs.c	rcu: Remove TINY_RCU bloat from pointless boot parameters	2015-12-07 16:59:37 -08:00
kthread.c
latencytop.c
Makefile
membarrier.c
memremap.c	mm, x86: get_user_pages() for dax mappings	2016-01-15 17:56:32 -08:00
module-internal.h
module.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching	2016-01-14 16:38:02 -08:00
module_signing.c	KEYS: Merge the type-specific data with the payload data	2015-10-21 15:18:36 +01:00
notifier.c
nsproxy.c
padata.c
panic.c	printk: do cond_resched() between lines while outputting to consoles	2016-01-16 11:17:25 -08:00
params.c	Nothing exciting, minor tweaks and cleanups.	2015-11-09 15:53:39 -08:00
pid.c	kmemcg: account certain kmem allocations to memcg	2016-01-14 16:00:49 -08:00
pid_namespace.c
profile.c
ptrace.c	ptrace: use fsuid, fsgid, effective creds for fs access checks	2016-01-20 17:09:18 -08:00
range.c
reboot.c
relay.c
resource.c	restrict /dev/mem to idle io memory ranges	2016-01-09 06:30:49 -08:00
seccomp.c	seccomp, ptrace: add support for dumping seccomp filters	2015-10-27 19:55:13 -07:00
signal.c	kernel/signal.c: unexport sigsuspend()	2015-11-20 16:17:32 -08:00
smp.c	mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd	2015-11-06 17:50:42 -08:00
smpboot.c	stop_machine: Kill smp_hotplug_thread->pre_unpark, introduce stop_machine_unpark()	2015-10-20 10:23:55 +02:00
smpboot.h
softirq.c
stacktrace.c
stop_machine.c	kernel/stop_machine.c: remove CONFIG_SMP dependencies	2016-01-16 11:17:24 -08:00
sys.c	prctl: take mmap sem for writing to protect against others	2016-01-20 17:09:18 -08:00
sys_ni.c	vfs: add copy_file_range syscall and vfs helper	2015-12-01 14:00:53 -05:00
sysctl.c	sysctl: enable strict writes	2016-01-20 17:09:18 -08:00
sysctl_binary.c
task_work.c
taskstats.c
test_kprobes.c
torture.c
tracepoint.c	tracepoint: Give priority to probes of tracepoints	2015-10-25 21:33:54 -04:00
tsacct.c
uid16.c
up.c
user-return-notifier.c
user.c
user_namespace.c	kernel/*: switch to memdup_user_nul()	2016-01-04 10:27:55 -05:00
utsname.c
utsname_sysctl.c
watchdog.c	Merge branch 'for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq	2016-01-11 18:53:13 -08:00
workqueue.c	workqueue: simplify the apply_workqueue_attrs_locked()	2016-01-07 11:04:34 -05:00
workqueue_internal.h