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49a2a07514
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Viresh Kumar 49a2a07514 hrtimer: Kick lowres dynticks targets on timer enqueue 
In lowres mode, hrtimers are serviced by the tick instead of a clock
event. It works well as long as the tick stays periodic but we must also
make sure that the hrtimers are serviced in dynticks mode targets,
pretty much like timer list timers do.

Note that all dynticks modes are concerned: get_nohz_timer_target()
tries not to return remote idle CPUs but there is nothing to prevent
the elected target from entering dynticks idle mode until we lock its
base. It's also prefectly legal to enqueue hrtimers on full dynticks CPU.

So there are two requirements to correctly handle dynticks:

1) On target's tick stop time, we must not delay the next tick further
   the next hrtimer.

2) On hrtimer queue time. If the tick of the target is stopped, we must
   wake up that CPU such that it sees the new hrtimer and recalculate
   the next tick accordingly.

The point 1 is well handled currently through get_nohz_timer_interrupt() and
cmp_next_hrtimer_event().

But the point 2 isn't handled at all.

Fixing this is easy though as we have the necessary API ready for that.
All we need is to call wake_up_nohz_cpu() on a target when a newly
enqueued hrtimer requires tick rescheduling, like timer list timer do.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/3d7ea08ce008698e26bd39fe10f55949391073ab.1403507178.git.viresh.kumar@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-06-23 11:23:47 +02:00
..
debug kdb: Use ktime_get_ts() 2014-06-12 16:18:45 +02:00
events Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm into next 2014-06-05 15:57:04 -07:00
gcov gcov: reuse kbasename helper 2013-11-13 12:09:34 +09:00
irq genirq: Improve documentation to match current implementation 2014-05-27 10:16:44 +02:00
locking Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next 2014-06-03 14:00:15 -07:00
power Merge branches 'pnp', 'powercap', 'pm-runtime' and 'pm-opp' 2014-06-03 23:13:00 +02:00
printk kernel/printk: use symbolic defines for console loglevels 2014-06-04 16:54:17 -07:00
rcu Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next 2014-06-03 12:57:53 -07:00
sched numa,sched: fix load_to_imbalanced logic inversion 2014-06-08 14:35:05 -07:00
time hrtimer: Kick lowres dynticks targets on timer enqueue 2014-06-23 11:23:47 +02:00
trace tracing: Use rcu_dereference_sched() for trace event triggers 2014-05-02 23:12:42 -04:00
.gitignore Ignore generated file kernel/x509_certificate_list 2013-12-10 18:21:34 +00:00
acct.c acct: Use ktime_get_ts() 2014-06-12 16:18:44 +02:00
async.c
audit_tree.c inotify: Fix reporting of cookies for inotify events 2014-02-18 11:17:17 +01:00
audit_watch.c inotify: Fix reporting of cookies for inotify events 2014-02-18 11:17:17 +01:00
audit.c ipc, kernel: use Linux headers 2014-06-06 16:08:14 -07:00
audit.h audit: Use struct net not pid_t to remember the network namespce to reply in 2014-03-20 10:10:53 -04:00
auditfilter.c Merge git://git.infradead.org/users/eparis/audit 2014-04-12 12:38:53 -07:00
auditsc.c Merge git://git.infradead.org/users/eparis/audit 2014-04-12 12:38:53 -07:00
backtracetest.c kernel/backtracetest.c: replace no level printk by pr_info() 2014-06-04 16:54:14 -07:00
bounds.c mm: do not allocate page->ptl dynamically, if spinlock_t fits to long 2013-12-20 12:25:45 -08:00
capability.c kernel/capability.c: code clean-up 2014-06-04 16:54:15 -07:00
cgroup_freezer.c cgroup: fix rcu_read_lock() leak in update_if_frozen() 2014-05-13 11:28:30 -04:00
cgroup.c kernfs: move the last knowledge of sysfs out from kernfs 2014-06-03 08:11:18 -07:00
compat.c kernel/compat.c: use sizeof() instead of sizeof 2014-06-04 16:54:19 -07:00
configs.c
context_tracking.c asmlinkage: Add explicit __visible to drivers/*, lib/*, kernel/* 2014-05-05 16:07:46 -07:00
cpu_pm.c
cpu.c kernel/cpu.c: convert printk to pr_foo() 2014-06-04 16:54:14 -07:00
cpuset.c mm: page_alloc: use jump labels to avoid checking number_of_cpusets 2014-06-04 16:54:08 -07:00
crash_dump.c
cred.c
delayacct.c delayacct: Use ktime_get_ts() 2014-06-12 16:18:45 +02:00
dma.c
elfcore.c switch elf_core_write_extra_phdrs() to dump_emit() 2013-11-09 00:16:23 -05:00
exec_domain.c kernel/exec_domain.c: code clean-up 2014-06-04 16:54:15 -07:00
exit.c signals: mv {dis,}allow_signal() from sched.h/exit.c to signal.[ch] 2014-06-06 16:08:11 -07:00
extable.c asmlinkage: Make main_extable_sort_needed visible 2014-02-13 18:13:22 -08:00
fork.c fork: Use ktime_get_ts() 2014-06-12 16:18:45 +02:00
freezer.c libata, freezer: avoid block device removal while system is frozen 2013-12-19 13:50:32 -05:00
futex_compat.c compat: Get rid of (get|put)_compat_time(val|spec) 2014-02-02 14:09:12 -08:00
futex.c Merge branch 'next' (accumulated 3.16 merge window patches) into master 2014-06-08 11:31:16 -07:00
groups.c kernel/groups.c: remove return value of set_groups 2014-04-03 16:21:05 -07:00
hung_task.c kernel/hung_task.c: convert simple_strtoul to kstrtouint 2014-06-04 16:54:15 -07:00
irq_work.c perf/x86: Warn to early_printk() in case irq_work is too slow 2014-02-21 21:49:07 +01:00
jump_label.c static_key: WARN on usage before jump_label_init was called 2013-10-19 19:45:35 -04:00
kallsyms.c kernel: use macros from compiler.h instead of __attribute__((...)) 2014-04-07 16:36:11 -07:00
kcmp.c
Kconfig.freezer
Kconfig.hz kernel: remove CONFIG_USE_GENERIC_SMP_HELPERS 2013-11-15 09:32:22 +09:00
Kconfig.locks
Kconfig.preempt
kexec.c kernel/kexec.c: convert printk to pr_foo() 2014-06-06 16:08:12 -07:00
kmod.c signals: change wait_for_helper() to use kernel_sigaction() 2014-06-06 16:08:12 -07:00
kprobes.c kprobes: use KSYM_NAME_LEN to size identifier buffers 2013-11-13 12:09:26 +09:00
ksysfs.c kobject: Make support for uevent_helper optional. 2014-04-25 12:00:49 -07:00
kthread.c kthread: fix return value of kthread_create() upon SIGKILL. 2014-06-04 16:53:51 -07:00
latencytop.c kernel/latencytop.c: convert seq_printf to seq_puts 2014-06-04 16:54:15 -07:00
Makefile time/timers: Move all time(r) related files into kernel/time 2014-06-23 11:22:35 +02:00
module_signing.c keys: change asymmetric keys to use common hash definitions 2013-10-25 17:15:18 -04:00
module-internal.h KEYS: Separate the kernel signature checking keyring from module signing 2013-09-25 17:17:01 +01:00
module.c Fixed one missing place for the new taint flag, and remove a warning 2014-05-01 10:35:01 -07:00
notifier.c notifier: Substitute rcu_access_pointer() for rcu_dereference_raw() 2014-02-26 06:35:13 -08:00
nsproxy.c
padata.c padata: Fix wrong usage of rcu_dereference() 2013-12-05 21:28:42 +08:00
panic.c kernel/panic.c: add "crash_kexec_post_notifiers" option for kdump after panic_notifers 2014-06-06 16:08:12 -07:00
params.c params: improve standard definitions 2013-12-04 14:09:46 +10:30
pid_namespace.c pid_namespace: pidns_get() should check task_active_pid_ns() != NULL 2014-04-02 16:20:21 -07:00
pid.c pidns: fix free_pid() to handle the first fork failure 2013-09-30 14:31:03 -07:00
profile.c kernel/profile.c: use static const char instead of static char 2014-06-06 16:08:13 -07:00
ptrace.c kernel/compat: convert to COMPAT_SYSCALL_DEFINE 2014-03-06 15:35:10 +01:00
range.c
reboot.c kernel/reboot.c: convert simple_strtoul to kstrtoint 2014-06-04 16:54:15 -07:00
relay.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-04-12 14:49:50 -07:00
res_counter.c kernel/res_counter.c: replace simple_strtoull by kstrtoull 2014-06-04 16:54:15 -07:00
resource.c resources: Clarify sanity check message 2014-05-23 10:47:21 -06:00
seccomp.c kernel/seccomp.c: kernel-doc warning fix 2014-06-06 16:08:15 -07:00
signal.c signals: introduce kernel_sigaction() 2014-06-06 16:08:12 -07:00
smp.c smp: print more useful debug info upon receiving IPI on an offline CPU 2014-06-06 16:08:12 -07:00
smpboot.c
smpboot.h
softirq.c 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
stacktrace.c
stop_machine.c kernel/stop_machine.c: kernel-doc warning fix 2014-06-04 16:54:15 -07:00
sys_ni.c sys_sgetmask/sys_ssetmask: add CONFIG_SGETMASK_SYSCALL 2014-06-04 16:54:14 -07:00
sys.c sched: Consolidate open coded implementations of nice level frobbing into nice_to_rlimit() and rlimit_to_nice() 2014-05-22 11:16:36 +02:00
sysctl_binary.c kernel/sysctl_binary.c: use scnprintf() instead of snprintf() 2013-11-13 12:09:33 +09:00
sysctl.c sysctl: convert use of typedef ctl_table to struct ctl_table 2014-06-06 16:08:16 -07:00
system_certificates.S KEYS: correct alignment of system_certificate_list content in assembly file 2013-12-10 18:25:28 +00:00
system_keyring.c KEYS: correct alignment of system_certificate_list content in assembly file 2013-12-10 18:25:28 +00:00
task_work.c task_work: documentation 2013-09-11 15:58:27 -07:00
taskstats.c genetlink: only pass array to genl_register_family_with_ops() 2013-11-19 16:39:05 -05:00
test_kprobes.c
torture.c torture: Remove __init from torture_init_begin/end 2014-05-14 09:46:30 -07:00
tracepoint.c kernel/tracepoint.c: kernel-doc fixes 2014-06-04 16:54:15 -07:00
tsacct.c tsacct: Use ktime_get_ts() 2014-06-12 16:18:45 +02:00
uid16.c
up.c smp: Rename __smp_call_function_single() to smp_call_function_single_async() 2014-02-24 14:47:15 -08:00
user_namespace.c kernel/user_namespace.c: kernel-doc/checkpatch fixes 2014-06-06 16:08:13 -07:00
user-return-notifier.c
user.c kernel/user.c: drop unused field 'files' from user_struct 2014-06-04 16:54:16 -07:00
utsname_sysctl.c sysctl: convert use of typedef ctl_table to struct ctl_table 2014-06-06 16:08:16 -07:00
utsname.c
watchdog.c kernel/watchdog.c:touch_softlockup_watchdog(): use raw_cpu_write() 2014-04-18 16:40:08 -07:00
workqueue_internal.h
workqueue.c Linux 3.15-rc6 2014-05-22 10:28:56 +02:00