1
linux/kernel
Arjan van de Ven 4c36a5dec2 [PATCH] round_jiffies infrastructure
Introduce a round_jiffies() function as well as a round_jiffies_relative()
function.  These functions round a jiffies value to the next whole second.
The primary purpose of this rounding is to cause all "we don't care exactly
when" timers to happen at the same jiffy.

This avoids multiple timers firing within the second for no real reason;
with dynamic ticks these extra timers cause wakeups from deep sleep CPU
sleep states and thus waste power.

The exact wakeup moment is skewed by the cpu number, to avoid all cpus from
waking up at the exact same time (and hitting the same lock/cachelines
there)

[akpm@osdl.org: fix variable type]
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-10 09:57:22 -08:00
..
irq [PATCH] CPEI gets warning at kernel/irq/migration.c:27/move_masked_irq() 2006-12-08 08:28:37 -08:00
power [PATCH] struct seq_operations and struct file_operations constification 2006-12-07 08:39:46 -08:00
time [PATCH] time_adjust cleared before use 2006-10-28 11:30:55 -07:00
.gitignore
acct.c [PATCH] kernel: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:42 -08:00
audit.c [PATCH] Add include/linux/freezer.h and move definitions from sched.h 2006-12-07 08:39:27 -08:00
audit.h [PATCH] audit: AUDIT_PERM support 2006-09-11 13:32:30 -04:00
auditfilter.c [PATCH] kernel core: replace kmalloc+memset with kzalloc 2006-12-07 08:39:41 -08:00
auditsc.c [PATCH] struct path: convert kernel 2006-12-08 08:28:46 -08:00
capability.c [PATCH] pidspace: is_init() 2006-09-29 09:18:12 -07:00
compat.c [PATCH] Create compat_sys_migrate_pages 2006-11-03 12:27:59 -08:00
configs.c [PATCH] struct seq_operations and struct file_operations constification 2006-12-07 08:39:46 -08:00
cpu.c [PATCH] suspend: don't change cpus_allowed for task initiating the suspend 2006-12-07 08:39:28 -08:00
cpuset.c [PATCH] struct path: convert kernel 2006-12-08 08:28:46 -08:00
delayacct.c [PATCH] slab: remove kmem_cache_t 2006-12-07 08:39:25 -08:00
dma.c [PATCH] struct seq_operations and struct file_operations constification 2006-12-07 08:39:46 -08:00
exec_domain.c
exit.c [PATCH] fdtable: Remove the free_files field 2006-12-10 09:57:22 -08:00
extable.c
fork.c [PATCH] fdtable: Remove the free_files field 2006-12-10 09:57:22 -08:00
futex_compat.c [PATCH] __user annotations: futex 2006-10-10 15:37:22 -07:00
futex.c [PATCH] kernel: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:42 -08:00
hrtimer.c [PATCH] posix-timers: Fix clock_nanosleep() doesn't return the remaining time in compatibility mode 2006-09-29 09:18:15 -07:00
itimer.c
kallsyms.c [PATCH] move kallsyms data to .rodata 2006-12-08 08:28:37 -08:00
Kconfig.hz [PATCH] HZ: 300Hz support 2006-12-07 08:39:36 -08:00
Kconfig.preempt
kexec.c Merge branch 'release' of master.kernel.org:/pub/scm/linux/kernel/git/aegl/linux-2.6 2006-12-07 15:39:22 -08:00
kfifo.c [PATCH] memory ordering in __kfifo primitives 2006-09-29 09:18:13 -07:00
kmod.c [PATCH] rename struct namespace to struct mnt_namespace 2006-12-08 08:28:51 -08:00
kprobes.c [PATCH] kprobes: enable booster on the preemptible kernel 2006-12-07 08:39:38 -08:00
ksysfs.c
kthread.c WorkStruct: Pass the work_struct pointer instead of context data 2006-11-22 14:55:48 +00:00
latency.c [PATCH] severing module.h->sched.h 2006-12-04 02:00:22 -05:00
lockdep_internals.h [PATCH] lockdep: more chains 2006-12-07 08:39:43 -08:00
lockdep_proc.c [PATCH] struct seq_operations and struct file_operations constification 2006-12-07 08:39:46 -08:00
lockdep.c Merge branch 'for-linus' of git://one.firstfloor.org/home/andi/git/linux-2.6 2006-12-07 08:59:11 -08:00
Makefile [PATCH] srcu-3: RCU variant permitting read-side blocking 2006-10-04 07:55:30 -07:00
module.c [PATCH] struct seq_operations and struct file_operations constification 2006-12-07 08:39:46 -08:00
mutex-debug.c [PATCH] lockdep: show more details about self-test failures 2006-12-07 08:39:43 -08:00
mutex-debug.h [PATCH] lockdep: better lock debugging 2006-07-03 15:27:01 -07:00
mutex.c [PATCH] lockdep: avoid lockdep warning in md 2006-12-08 08:28:39 -08:00
mutex.h [PATCH] lockdep: prove mutex locking correctness 2006-07-03 15:27:04 -07:00
nsproxy.c [PATCH] to nsproxy 2006-12-08 08:28:52 -08:00
panic.c [PATCH] x86: Clean up x86 NMI sysctls 2006-09-30 01:47:55 +02:00
params.c [PATCH] module_subsys: initialize earlier 2006-09-29 09:18:08 -07:00
pid.c [PATCH] add child reaper to pid_namespace 2006-12-08 08:28:52 -08:00
posix-cpu-timers.c [PATCH] posix-cpu-timers: prevent signal delivery starvation 2006-10-17 08:18:43 -07:00
posix-timers.c [PATCH] slab: remove kmem_cache_t 2006-12-07 08:39:25 -08:00
printk.c [PATCH] add ignore_loglevel boot option 2006-12-07 08:39:47 -08:00
profile.c [PATCH] struct seq_operations and struct file_operations constification 2006-12-07 08:39:46 -08:00
ptrace.c [PATCH] pidspace: is_init() 2006-09-29 09:18:12 -07:00
rcupdate.c [PATCH] rcu: add a prefetch() in rcu_do_batch() 2006-12-07 08:39:40 -08:00
rcutorture.c [PATCH] Add Sparse annotations to SRCU wrapper functions in rcutorture 2006-12-07 08:39:44 -08:00
relay.c [PATCH] kernel: change uses of f_{dentry, vfsmnt} to use f_path 2006-12-08 08:28:42 -08:00
resource.c [PATCH] struct seq_operations and struct file_operations constification 2006-12-07 08:39:46 -08:00
rtmutex_common.h
rtmutex-debug.c Remove all inclusions of <linux/config.h> 2006-10-04 03:38:54 -04:00
rtmutex-debug.h [PATCH] lockdep: better lock debugging 2006-07-03 15:27:01 -07:00
rtmutex-tester.c [PATCH] Add include/linux/freezer.h and move definitions from sched.h 2006-12-07 08:39:27 -08:00
rtmutex.c [PATCH] clean up and remove some extra spinlocks from rtmutex 2006-09-29 09:18:09 -07:00
rtmutex.h [PATCH] lockdep: better lock debugging 2006-07-03 15:27:01 -07:00
rwsem.c [PATCH] lockdep: prove rwsem locking correctness 2006-07-03 15:27:04 -07:00
sched.c [PATCH] kernel/sched.c: whitespace cleanups 2006-12-10 09:57:20 -08:00
seccomp.c
signal.c [PATCH] add child reaper to pid_namespace 2006-12-08 08:28:52 -08:00
softirq.c [PATCH] softirq: remove BUG_ONs which can incorrectly trigger 2006-12-07 08:39:43 -08:00
softlockup.c [PATCH] check return value of cpu_callback 2006-09-29 09:18:14 -07:00
spinlock.c [PATCH] lockdep: spin_lock_irqsave_nested() 2006-11-25 13:28:34 -08:00
srcu.c [PATCH] SRCU: report out-of-memory errors 2006-10-04 07:55:30 -07:00
stacktrace.c [PATCH] lockdep: stacktrace subsystem, core 2006-07-03 15:27:02 -07:00
stop_machine.c [PATCH] stop_machine.c copyright 2006-09-29 09:18:24 -07:00
sys_ni.c [PATCH] Create compat_sys_migrate_pages 2006-11-03 12:27:59 -08:00
sys.c [PATCH] sys_setpgid: eliminate unnecessary do_each_task_pid(PIDTYPE_PGID) 2006-12-08 08:28:52 -08:00
sysctl.c [PATCH] sysctl: remove unused "context" param 2006-12-10 09:55:41 -08:00
taskstats.c [PATCH] taskstats: cleanup reply assembling 2006-12-07 08:39:34 -08:00
time.c [PATCH] NTP: Move all the NTP related code to ntp.c 2006-10-01 00:39:26 -07:00
timer.c [PATCH] round_jiffies infrastructure 2006-12-10 09:57:22 -08:00
tsacct.c [PATCH] io-accounting: via taskstats 2006-12-10 09:55:41 -08:00
uid16.c
unwind.c [PATCH] unwinder: move .eh_frame to RODATA 2006-12-07 02:14:19 +01:00
user.c [PATCH] slab: remove kmem_cache_t 2006-12-07 08:39:25 -08:00
utsname.c [PATCH] namespaces: utsname: implement CLONE_NEWUTS flag 2006-10-02 07:57:22 -07:00
wait.c [PATCH] uninline init_waitqueue_head() 2006-07-10 13:24:25 -07:00
workqueue.c [PATCH] WorkStruct: Use direct assignment rather than cmpxchg() 2006-12-09 12:25:08 -08:00