Repository files (latest commit first)

Filename	Latest commit message	Latest commit date
Tejun Heo ed27b9f7a1 cgroup: don't hold css_set_rwsem across css task iteration ... css_sets are synchronized through css_set_rwsem but the locking scheme is kinda bizarre. The hot paths - fork and exit - have to write lock the rwsem making the rw part pointless; furthermore, many readers already hold cgroup_mutex. One of the readers is css task iteration. It read locks the rwsem over the entire duration of iteration. This leads to silly locking behavior. When cpuset tries to migrate processes of a cgroup to a different NUMA node, css_set_rwsem is held across the entire migration attempt which can take a long time locking out forking, exiting and other cgroup operations. This patch updates css task iteration so that it locks css_set_rwsem only while the iterator is being advanced. css task iteration involves two levels - css_set and task iteration. As css_sets in use are practically immutable, simply pinning the current one is enough for resuming iteration afterwards. Task iteration is tricky as tasks may leave their css_set while iteration is in progress. This is solved by keeping track of active iterators and advancing them if their next task leaves its css_set. v2: put_task_struct() in css_task_iter_next() moved outside css_set_rwsem. A later patch will add cgroup operations to task_struct free path which may grab the same lock and this avoids deadlock possibilities. css_set_move_task() updated to use list_for_each_entry_safe() when walking task_iters and advancing them. This is necessary as advancing an iter may remove it from the list. Signed-off-by: Tejun Heo <tj@kernel.org>		2015-10-15 16:41:52 -04:00
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bpf	bpf: fix out of bounds access in verifier log	2015-09-09 14:11:55 -07:00
configs	kconfig: add xenconfig defconfig helper	2015-06-16 11:04:29 +01:00
debug
events	kexec: split kexec_load syscall from kexec core code	2015-09-10 13:29:01 -07:00
gcov	gcov: add support for GCC 5.1	2015-06-30 19:44:57 -07:00
irq	Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-09-01 14:33:35 -07:00
livepatch	livepatch: Improve error handling in klp_disable_func()	2015-07-14 22:48:06 +02:00
locking	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2015-09-05 20:34:28 -07:00
power	Merge branch 'for-4.3/core' of git://git.kernel.dk/linux-block	2015-09-02 13:10:25 -07:00
printk	kexec: split kexec_load syscall from kexec core code	2015-09-10 13:29:01 -07:00
rcu	rcu,locking: Privatize smp_mb__after_unlock_lock()	2015-08-04 08:49:21 -07:00
sched	userfaultfd: waitqueue: add nr wake parameter to __wake_up_locked_key	2015-09-04 16:54:41 -07:00
time	Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-09-01 14:04:50 -07:00
trace	Mostly this is just clean ups and micro optimizations.	2015-09-08 14:04:14 -07:00
.gitignore
acct.c
async.c
audit.c	Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit	2015-09-08 13:34:59 -07:00
audit.h	Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit	2015-09-08 13:34:59 -07:00
audit_fsnotify.c	audit: clean simple fsnotify implementation	2015-08-06 16:14:53 -04:00
audit_tree.c	Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit	2015-09-08 13:34:59 -07:00
audit_watch.c	Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit	2015-09-08 13:34:59 -07:00
auditfilter.c	audit: implement audit by executable	2015-08-06 16:17:25 -04:00
auditsc.c	Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit	2015-09-08 13:34:59 -07:00
backtracetest.c
bounds.c
capability.c
cgroup.c	cgroup: don't hold css_set_rwsem across css task iteration	2015-10-15 16:41:52 -04:00
cgroup_freezer.c	cgroup: allow a cgroup subsystem to reject a fork	2015-07-14 17:29:23 -04:00
cgroup_pids.c	cgroup: pids: fix invalid get/put usage	2015-08-25 14:19:25 -04:00
compat.c
configs.c
context_tracking.c
cpu.c	Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-08-31 20:26:22 -07:00
cpu_pm.c	kernel/cpu_pm: fix cpu_cluster_pm_exit comment	2015-09-03 02:42:20 +02:00
cpuset.c	cgroup: replace cgroup_has_tasks() with cgroup_is_populated()	2015-10-15 16:41:50 -04:00
crash_dump.c
cred.c	kernel/cred.c: remove unnecessary kdebug atomic reads	2015-09-10 13:29:01 -07:00
delayacct.c
dma.c
elfcore.c
exec_domain.c
exit.c	kernel: exit: fix typo in comment	2015-08-07 13:59:49 +02:00
extable.c	kernel/extable.c: remove duplicated include	2015-09-10 13:29:01 -07:00
fork.c	sched, cgroup: replace signal_struct->group_rwsem with a global percpu_rwsem	2015-09-16 12:53:17 -04:00
freezer.c
futex.c	futex: Make should_fail_futex() static	2015-07-20 21:43:54 +02:00
futex_compat.c
groups.c
hung_task.c
irq_work.c
jump_label.c	locking/static_keys: Add selftest	2015-08-03 11:34:16 +02:00
kallsyms.c
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kexec.c	kexec: split kexec_load syscall from kexec core code	2015-09-10 13:29:01 -07:00
kexec_core.c	kexec: export KERNEL_IMAGE_SIZE to vmcoreinfo	2015-09-10 13:29:01 -07:00
kexec_file.c	kexec: split kexec_file syscall code to kexec_file.c	2015-09-10 13:29:01 -07:00
kexec_internal.h	kexec: split kexec_file syscall code to kexec_file.c	2015-09-10 13:29:01 -07:00
kmod.c	kmod: handle UMH_WAIT_PROC from system unbound workqueue	2015-09-10 13:29:01 -07:00
kprobes.c	perf/x86/hw_breakpoints: Disallow kernel breakpoints unless kprobe-safe	2015-08-04 10:16:54 +02:00
ksysfs.c	kexec: split kexec_load syscall from kexec core code	2015-09-10 13:29:01 -07:00
kthread.c	kernel/kthread.c:kthread_create_on_node(): clarify documentation	2015-09-04 16:54:41 -07:00
latencytop.c
Makefile	sys_membarrier(): system-wide memory barrier (generic, x86)	2015-09-11 15:21:34 -07:00
membarrier.c	sys_membarrier(): system-wide memory barrier (generic, x86)	2015-09-11 15:21:34 -07:00
memremap.c	add devm_memremap_pages	2015-08-27 19:40:58 -04:00
module-internal.h
module.c	module: weaken locking assertion for oops path.	2015-07-29 06:13:22 +09:30
module_signing.c	PKCS#7: Appropriately restrict authenticated attributes and content type	2015-08-12 17:01:01 +01:00
notifier.c	Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-09-01 08:40:25 -07:00
nsproxy.c
padata.c
panic.c	kernel/panic/kexec: fix "crash_kexec_post_notifiers" option issue in oops path	2015-06-30 19:44:57 -07:00
params.c	Minor merge needed, due to function move.	2015-07-01 10:49:25 -07:00
pid.c	rcu: Rename rcu_lockdep_assert() to RCU_LOCKDEP_WARN()	2015-07-22 15:27:32 -07:00
pid_namespace.c
profile.c	mm: rename alloc_pages_exact_node() to __alloc_pages_node()	2015-09-08 15:35:28 -07:00
ptrace.c	seccomp: add ptrace options for suspend/resume	2015-07-15 11:52:52 -07:00
range.c
reboot.c	kexec: split kexec_load syscall from kexec core code	2015-09-10 13:29:01 -07:00
relay.c	kernel/relay.c: use kvfree() in relay_free_page_array()	2015-06-30 19:44:59 -07:00
resource.c	mm: enhance region_is_ram() to region_intersects()	2015-08-10 23:07:05 -04:00
seccomp.c	Merge tag 'seccomp-next' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux into next	2015-07-20 17:19:19 +10:00
signal.c	signal: fix information leak in copy_siginfo_to_user	2015-08-07 04:39:40 +03:00
smp.c
smpboot.c	smpboot: allow passing the cpumask on per-cpu thread registration	2015-09-04 16:54:41 -07:00
smpboot.h
softirq.c
stacktrace.c
stop_machine.c	stop_machine: Remove cpu_stop_work's from list in cpu_stop_park()	2015-08-03 12:21:28 +02:00
sys.c	vfs: Commit to never having exectuables on proc and sysfs.	2015-07-10 10:39:25 -05:00
sys_ni.c	sys_membarrier(): system-wide memory barrier (generic, x86)	2015-09-11 15:21:34 -07:00
sysctl.c	sysctl: fix int -> unsigned long assignments in INT_MIN case	2015-09-10 13:29:01 -07:00
sysctl_binary.c
task_work.c	task_work: remove fifo ordering guarantee	2015-09-05 13:46:58 -07:00
taskstats.c
test_kprobes.c
torture.c
tracepoint.c
tsacct.c
uid16.c
up.c
user-return-notifier.c
user.c
user_namespace.c	capabilities: ambient capabilities	2015-09-04 16:54:41 -07:00
utsname.c
utsname_sysctl.c
watchdog.c	watchdog: rename watchdog_suspend() and watchdog_resume()	2015-09-04 16:54:41 -07:00
workqueue.c	Merge branch 'for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq	2015-09-02 08:02:20 -07:00
workqueue_internal.h