Jack Miller
ab602f7991
shm: make exit_shm work proportional to task activity ...
This is small set of patches our team has had kicking around for a few
versions internally that fixes tasks getting hung on shm_exit when there
are many threads hammering it at once.
Anton wrote a simple test to cause the issue:
http://ozlabs.org/~anton/junkcode/bust_shm_exit.c
Before applying this patchset, this test code will cause either hanging
tracebacks or pthread out of memory errors.
After this patchset, it will still produce output like:
root@somehost:~# ./bust_shm_exit 1024 160
...
INFO: rcu_sched detected stalls on CPUs/tasks: {} (detected by 116, t=2111 jiffies, g=241, c=240, q=7113)
INFO: Stall ended before state dump start
...
But the task will continue to run along happily, so we consider this an
improvement over hanging, even if it's a bit noisy.
This patch (of 3):
exit_shm obtains the ipc_ns shm rwsem for write and holds it while it
walks every shared memory segment in the namespace. Thus the amount of
work is related to the number of shm segments in the namespace not the
number of segments that might need to be cleaned.
In addition, this occurs after the task has been notified the thread has
exited, so the number of tasks waiting for the ns shm rwsem can grow
without bound until memory is exausted.
Add a list to the task struct of all shmids allocated by this task. Init
the list head in copy_process. Use the ns->rwsem for locking. Add
segments after id is added, remove before removing from id.
On unshare of NEW_IPCNS orphan any ids as if the task had exited, similar
to handling of semaphore undo.
I chose a define for the init sequence since its a simple list init,
otherwise it would require a function call to avoid include loops between
the semaphore code and the task struct. Converting the list_del to
list_del_init for the unshare cases would remove the exit followed by
init, but I left it blow up if not inited.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Jack Miller <millerjo@us.ibm.com>
Cc: Davidlohr Bueso <davidlohr@hp.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08 15:57:26 -07:00
net: filter: split 'struct sk_filter' into socket and bpf parts
2014-08-02 15:03:58 -07:00
kdb: Use ktime_get_ts()
2014-06-12 16:18:45 +02:00
mm: memcontrol: rewrite charge API
2014-08-08 15:57:17 -07:00
kernel/gcov/fs.c: remove unnecessary null test before debugfs_remove
2014-08-08 15:57:24 -07:00
Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2014-08-05 17:38:45 -07:00
arch, locking: Ciao arch_mutex_cpu_relax()
2014-07-17 12:32:47 +02:00
ACPI and power management updates for 3.17-rc1
2014-08-06 20:34:19 -07:00
kernel/printk/printk.c: fix bool assignements
2014-08-06 18:01:24 -07:00
Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2014-08-04 15:55:08 -07:00
ACPI and power management updates for 3.17-rc1
2014-08-06 20:34:19 -07:00
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2014-08-05 17:46:42 -07:00
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2014-08-05 17:46:42 -07:00
sched: Make task->start_time nanoseconds based
2014-07-23 10:18:05 -07:00
CAPABILITIES: remove undefined caps from all processes
2014-07-24 21:53:47 +10:00
kernel/auditfilter.c: replace count*size kmalloc by kcalloc
2014-08-06 18:01:12 -07:00
auditsc: audit_krule mask accesses need bounds checking
2014-06-10 08:44:40 -07:00
kernel/backtracetest.c: replace no level printk by pr_info()
2014-06-04 16:54:14 -07:00
page-cgroup: get rid of NR_PCG_FLAGS
2014-08-08 15:57:18 -07:00
CAPABILITIES: remove undefined caps from all processes
2014-07-24 21:53:47 +10:00
Merge branch 'for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
2014-08-04 10:11:28 -07:00
cgroup: rename cgroup_subsys->base_cftypes to ->legacy_cftypes
2014-07-15 11:05:09 -04:00
kernel/compat.c: use sizeof() instead of sizeof
2014-06-04 16:54:19 -07:00
x86/kprobes: Fix build errors and blacklist context_track_user
2014-06-14 09:07:44 +02:00
sched: Rework check_for_tasks()
2014-07-05 11:17:45 +02:00
Merge branch 'for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
2014-08-04 10:11:28 -07:00
delayacct: Remove braindamaged type conversions
2014-07-23 10:18:06 -07:00
kernel/exec_domain.c: code clean-up
2014-06-04 16:54:15 -07:00
kernel/exit.c: fix coding style warnings and errors
2014-08-08 15:57:22 -07:00
shm: make exit_shm work proportional to task activity
2014-08-08 15:57:26 -07:00
futex: Simplify futex_lock_pi_atomic() and make it more robust
2014-06-21 22:26:24 +02:00
kernel/hung_task.c: convert simple_strtoul to kstrtouint
2014-06-04 16:54:15 -07:00
irq_work: Remove BUG_ON in irq_work_run()
2014-07-05 11:17:26 +02:00
kernel/kallsyms.c: fix %pB when there's no symbol at the address
2014-08-08 15:57:18 -07:00
locking/rwsem: Add CONFIG_RWSEM_SPIN_ON_OWNER
2014-07-16 14:57:13 +02:00
kexec: fix build error when hugetlbfs is disabled
2014-07-30 20:09:37 -07:00
signals: change wait_for_helper() to use kernel_sigaction()
2014-06-06 16:08:12 -07:00
kprobes: Fix "Failed to find blacklist" probing errors on ia64 and ppc64
2014-07-18 06:23:40 +02:00
kthread_work: wake up worker only when the worker is idle
2014-07-28 14:07:52 -04:00
kernel/latencytop.c: convert seq_printf to seq_puts
2014-06-04 16:54:15 -07:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
2014-08-06 09:38:14 -07:00
crypto: fips - only panic on bad/missing crypto mod signatures
2014-07-03 21:38:32 +08:00
panic: add TAINT_SOFTLOCKUP
2014-08-08 15:57:24 -07:00
Add module param type 'ullong'
2014-07-17 22:07:37 +02:00
kernel/profile.c: use static const char instead of static char
2014-06-06 16:08:13 -07:00
sched: Remove proliferation of wait_on_bit() action functions
2014-07-16 15:10:39 +02:00
kernel/reboot.c: convert simple_strtoul to kstrtoint
2014-06-04 16:54:15 -07:00
kernel/res_counter.c: replace simple_strtoull by kstrtoull
2014-06-04 16:54:15 -07:00
resources: Clarify sanity check message
2014-05-23 10:47:21 -06:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
2014-08-06 09:38:14 -07:00
signal: Explain local_irq_save() call
2014-07-09 09:14:33 -07:00
kernel/smp.c:on_each_cpu_cond(): fix warning in fallback path
2014-08-06 18:01:22 -07:00
Merge branch 'rcu/next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
2014-05-22 11:36:10 +02:00
kernel/stop_machine.c: kernel-doc warning fix
2014-06-04 16:54:15 -07:00
sched: move no_new_privs into new atomic flags
2014-07-18 12:13:38 -07:00
seccomp: add "seccomp" syscall
2014-07-18 12:13:37 -07:00
mm, hugetlb: remove hugetlb_zero and hugetlb_infinity
2014-08-06 18:01:19 -07:00
ipv6: Allow accepting RA from local IP addresses.
2014-07-01 12:16:24 -07:00
KEYS: validate certificate trust only with builtin keys
2014-07-17 09:35:17 -04:00
kernel/test_kprobes.c: use current logging functions
2014-08-08 15:57:18 -07:00
torture: Avoid format string leak to thead name
2014-07-07 10:12:56 -07:00
tracing: syscall_regfunc() should not skip kernel threads
2014-06-21 00:15:26 -04:00
sched: Make task->start_time nanoseconds based
2014-07-23 10:18:05 -07:00
kernel/user.c: drop unused field 'files' from user_struct
2014-06-04 16:54:16 -07:00
proc: constify seq_operations
2014-08-08 15:57:22 -07:00
sysctl: convert use of typedef ctl_table to struct ctl_table
2014-06-06 16:08:16 -07:00
panic: add TAINT_SOFTLOCKUP
2014-08-08 15:57:24 -07:00
Merge branch 'for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
2014-08-04 10:09:27 -07:00
workqueue: rename manager_mutex to attach_mutex
2014-05-20 10:59:32 -04:00
ab602f7991