Chris Metcalf
fe4ba3c343
watchdog: add watchdog_cpumask sysctl to assist nohz ...
Change the default behavior of watchdog so it only runs on the
housekeeping cores when nohz_full is enabled at build and boot time.
Allow modifying the set of cores the watchdog is currently running on
with a new kernel.watchdog_cpumask sysctl.
In the current system, the watchdog subsystem runs a periodic timer that
schedules the watchdog kthread to run. However, nohz_full cores are
designed to allow userspace application code running on those cores to
have 100% access to the CPU. So the watchdog system prevents the
nohz_full application code from being able to run the way it wants to,
thus the motivation to suppress the watchdog on nohz_full cores, which
this patchset provides by default.
However, if we disable the watchdog globally, then the housekeeping
cores can't benefit from the watchdog functionality. So we allow
disabling it only on some cores. See Documentation/lockup-watchdogs.txt
for more information.
[jhubbard@nvidia.com: fix a watchdog crash in some configurations]
Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-24 17:49:40 -07:00
bpf: fix 64-bit divide
2015-04-27 23:11:49 -04:00
x86: Add "make tinyconfig" to configure the tiniest possible kernel
2014-08-08 16:30:24 -07:00
debug: prevent entering debug mode on panic/exception.
2015-02-19 12:39:03 -06:00
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2015-06-22 18:57:44 -07:00
gcov: fix softlockups
2015-04-17 09:04:08 -04:00
Merge branch 'irq/for-x86' into irq/core
2015-06-20 19:14:31 +02:00
Merge branches 'for-4.1/upstream-fixes', 'for-4.2/kaslr' and 'for-4.2/upstream' into for-linus
2015-06-22 16:26:56 +02:00
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2015-06-22 18:57:44 -07:00
PM / sleep: Return -EBUSY from suspend_enter() on wakeup detection
2015-05-19 02:26:56 +02:00
TTY/Serial patches for 4.1-rc1
2015-04-21 09:33:10 -07:00
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2015-06-22 18:57:44 -07:00
Power management and ACPI material for v4.2-rc1
2015-06-23 14:18:07 -07:00
Power management and ACPI material for v4.2-rc1
2015-06-23 14:18:07 -07:00
tracing: Have filter check for balanced ops
2015-06-17 07:13:30 -04:00
acct: check FMODE_CAN_WRITE
2015-04-11 22:27:55 -04:00
kernel/async.c: switch to pr_foo()
2014-10-09 22:26:04 -04:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2015-04-26 17:22:07 -07:00
Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit
2015-04-22 14:49:23 -07:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2015-04-26 17:22:07 -07:00
VFS: audit: d_backing_inode() annotations
2015-04-15 15:06:55 -04:00
Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit
2015-02-11 20:07:47 -08:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2015-04-26 17:22:07 -07:00
page-cgroup: get rid of NR_PCG_FLAGS
2014-08-08 15:57:18 -07:00
kernel: conditionally support non-root users, groups and capabilities
2015-04-15 16:35:22 -07:00
cgroup: remove use of seq_printf return value
2015-04-15 16:35:25 -07:00
cgroup: rename cgroup_subsys->base_cftypes to ->legacy_cftypes
2014-07-15 11:05:09 -04:00
compat: cleanup coding in compat_get_bitmap() and compat_put_bitmap()
2015-06-04 23:57:18 +02:00
context_tracking: Inherit TIF_NOHZ through forks instead of context switches
2015-05-07 12:02:51 +02:00
cpu: Remove new instance of __cpuinit that crept back in
2015-05-27 12:58:39 -07:00
kernel, cpuset: remove exception for __GFP_THISNODE
2015-04-14 16:49:03 -07:00
crash_dump: Make is_kdump_kernel() accessible from modules
2014-08-25 15:42:19 -07:00
kernel: conditionally support non-root users, groups and capabilities
2015-04-15 16:35:22 -07:00
delayacct: Remove braindamaged type conversions
2014-07-23 10:18:06 -07:00
Remove rest of exec domains.
2015-04-12 21:03:31 +02:00
Remove execution domain support
2015-04-12 20:58:24 +02:00
ftrace/x86/extable: Add is_ftrace_trampoline() function
2014-11-19 15:25:26 -05:00
sched/preempt, mm/fault: Count pagefault_disable() levels in pagefault_disabled
2015-05-19 08:39:13 +02:00
freezer: remove obsolete comments in __thaw_task()
2014-10-21 23:44:20 +02:00
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2015-06-22 18:57:44 -07:00
kernel: conditionally support non-root users, groups and capabilities
2015-04-15 16:35:22 -07:00
kernel/hung_task.c: change hung_task.c to use for_each_process_thread()
2015-04-15 16:35:22 -07:00
percpu: Convert remaining __get_cpu_var uses in 3.18-rcX
2014-10-29 11:18:18 -04:00
kernel/kallsyms.c: use __seq_open_private()
2014-10-14 02:18:16 +02:00
kcmp: fix standard comparison bug
2014-09-10 15:42:12 -07:00
locking/qrwlock: Rename QUEUE_RWLOCK to QUEUED_RWLOCKS
2015-05-12 09:46:00 +02:00
kexec: allocate the kexec control page with KEXEC_CONTROL_MEMORY_GFP
2015-04-23 16:52:01 +02:00
usermodehelper: kill the kmod_thread_locker logic
2014-12-10 17:41:17 -08:00
kprobes: makes kprobes/enabled works correctly for optimized kprobes.
2015-02-13 21:21:42 -08:00
kernel/kthread.c: partial revert of 81c98869fa ("kthread: ensure locality of task_struct allocations")
2014-10-09 22:25:51 -04:00
modsign: change default key details
2015-04-30 09:35:41 -07:00
module: Call module notifier on failure after complete_formation()
2015-05-09 03:29:24 +09:30
rcu: Make SRCU optional by using CONFIG_SRCU
2015-01-06 11:04:29 -08:00
bury struct proc_ns in fs/proc
2014-12-04 14:34:54 -05:00
padata: use %*pb[l] to print bitmaps including cpumasks and nodemasks
2015-02-13 21:21:38 -08:00
livepatch: kernel: add TAINT_LIVEPATCH
2014-12-22 15:40:48 +01:00
params: handle quotes properly for values not of form foo="bar".
2015-04-15 13:31:23 +09:30
fork: report pid reservation failure properly
2015-04-17 09:04:06 -04:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2014-12-16 15:53:03 -08:00
profile: use %*pb[l] to print bitmaps including cpumasks and nodemasks
2015-02-13 21:21:38 -08:00
ptrace: ptrace_detach() can no longer race with SIGKILL
2015-04-17 09:04:06 -04:00
kernel: avoid overflow in cmp_range
2015-01-17 10:02:23 +13:00
kernel/reboot.c: add orderly_reboot for graceful reboot
2015-04-15 16:35:23 -07:00
VFS: kernel/: d_inode() annotations
2015-04-15 15:06:55 -04:00
kernel/resource.c: remove deprecated __check_region() and friends
2015-04-15 16:35:22 -07:00
seccomp: cap SECCOMP_RET_ERRNO data to MAX_ERRNO
2015-02-17 14:34:55 -08:00
signals, sched: Change all uses of JOBCTL_* from 'int' to 'long'
2015-05-08 12:04:36 +02:00
smp: Fix error case handling in smp_call_function_*()
2015-04-19 13:19:23 -07:00
watchdog: add watchdog_cpumask sysctl to assist nohz
2015-06-24 17:49:40 -07:00
Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2015-02-09 15:24:03 -08:00
stacktrace: introduce snprint_stack_trace for buffer output
2014-12-13 12:42:48 -08:00
sched/stop_machine: Fix deadlock between multiple stop_two_cpus()
2015-06-19 10:03:12 +02:00
x86/mpx: Clean up the code by not passing a task pointer around when unnecessary
2015-06-09 12:24:30 +02:00
kernel: conditionally support non-root users, groups and capabilities
2015-04-15 16:35:22 -07:00
watchdog: add watchdog_cpumask sysctl to assist nohz
2015-06-24 17:49:40 -07:00
kernel: add panic_on_warn
2014-12-10 17:41:10 -08:00
KEYS: validate certificate trust only with builtin keys
2014-07-17 09:35:17 -04:00
netlink: make nlmsg_end() and genlmsg_end() void
2015-01-18 01:03:45 -05:00
kernel/test_kprobes.c: use current logging functions
2014-08-08 15:57:18 -07:00
rcu: Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE()
2015-05-27 12:56:15 -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
groups: Consolidate the setgroups permission checks
2014-12-05 17:19:27 -06:00
scheduler: Replace __get_cpu_var with this_cpu_ptr
2014-08-26 13:45:45 -04:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
2014-12-17 12:31:40 -08:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
2014-12-17 12:31:40 -08:00
copy address of proc_ns_ops into ns_common
2014-12-04 14:34:47 -05:00
sysctl: convert use of typedef ctl_table to struct ctl_table
2014-06-06 16:08:16 -07:00
watchdog: add watchdog_cpumask sysctl to assist nohz
2015-06-24 17:49:40 -07:00
workqueue: Reorder sysfs code
2015-04-06 11:16:04 -04:00
fe4ba3c343