linux/kernel
Martin Schwidefsky 79741dd357 [PATCH] idle cputime accounting
The cpu time spent by the idle process actually doing something is
currently accounted as idle time. This is plain wrong, the architectures
that support VIRT_CPU_ACCOUNTING=y can do better: distinguish between the
time spent doing nothing and the time spent by idle doing work. The first
is accounted with account_idle_time and the second with account_system_time.
The architectures that use the account_xxx_time interface directly and not
the account_xxx_ticks interface now need to do the check for the idle
process in their arch code. In particular to improve the system vs true
idle time accounting the arch code needs to measure the true idle time
instead of just testing for the idle process.
To improve the tick based accounting as well we would need an architecture
primitive that can tell us if the pt_regs of the interrupted context
points to the magic instruction that halts the cpu.

In addition idle time is no more added to the stime of the idle process.
This field now contains the system time of the idle process as it should
be. On systems without VIRT_CPU_ACCOUNTING this will always be zero as
every tick that occurs while idle is running will be accounted as idle
time.

This patch contains the necessary common code changes to be able to
distinguish idle system time and true idle time. The architectures with
support for VIRT_CPU_ACCOUNTING need some changes to exploit this.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-31 15:11:46 +01:00
..
irq Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-12-30 16:20:19 -08:00
power Merge branches 'tracing/ftrace', 'tracing/ring-buffer' and 'tracing/urgent' into tracing/core 2008-12-19 09:42:40 +01:00
time [PATCH] idle cputime accounting 2008-12-31 15:11:46 +01:00
trace tracing: removed duplicated #include 2008-12-30 17:35:40 -08:00
.gitignore
acct.c CRED: Wrap task credential accesses in the core kernel 2008-11-14 10:39:12 +11:00
audit_tree.c Fix inotify watch removal/umount races 2008-11-15 12:26:44 -08:00
audit.c [PATCH] fix broken timestamps in AVC generated by kernel threads 2008-12-09 02:27:41 -05:00
audit.h
auditfilter.c Fix inotify watch removal/umount races 2008-11-15 12:26:44 -08:00
auditsc.c Merge branch 'next' into for-linus 2008-12-25 11:40:09 +11:00
backtracetest.c
bounds.c
capability.c CRED: Inaugurate COW credentials 2008-11-14 10:39:23 +11:00
cgroup_debug.c cgroups: fix probable race with put_css_set[_taskexit] and find_css_set 2008-10-20 08:52:38 -07:00
cgroup_freezer.c freezer_cg: disable writing freezer.state of root cgroup 2008-11-12 17:17:16 -08:00
cgroup.c Merge branch 'next' into for-linus 2008-12-25 11:40:09 +11:00
compat.c Merge branches 'timers/clocksource', 'timers/hrtimers', 'timers/nohz', 'timers/ntp', 'timers/posixtimers' and 'timers/debug' into v28-timers-for-linus 2008-10-20 13:14:06 +02:00
configs.c kernel/configs.c: remove useless comments 2008-10-20 08:52:34 -07:00
cpu.c cpuinit fixes in kernel/* 2008-11-30 10:03:37 -08:00
cpuset.c sched, cpusets: fix warning in kernel/cpuset.c 2008-11-29 20:39:29 +01:00
cred-internals.h CRED: Inaugurate COW credentials 2008-11-14 10:39:23 +11:00
cred.c User namespaces: set of cleanups (v2) 2008-11-24 18:57:41 -05:00
delayacct.c schedstat: consolidate per-task cpu runtime stats 2008-12-18 13:54:01 +01:00
dma-coherent.c dma-coherent: export dma_[alloc|release]_from_coherent methods 2008-08-22 08:34:53 +02:00
dma.c kernel/dma.c: remove a CVS keyword 2008-10-16 11:21:30 -07:00
exec_domain.c proc: move /proc/execdomains to kernel/exec_domain.c 2008-10-23 14:30:41 +04:00
exit.c Merge branch 'for-2.6.29' of git://git.kernel.dk/linux-2.6-block 2008-12-30 17:20:05 -08:00
extable.c Merge branch 'core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-12-30 16:10:19 -08:00
fork.c aio: make the lookup_ioctx() lockless 2008-12-29 08:29:50 +01:00
freezer.c freezer_cg: use thaw_process() in unfreeze_cgroup() 2008-10-30 11:38:45 -07:00
futex_compat.c CRED: Use RCU to access another task's creds and to release a task's own creds 2008-11-14 10:39:19 +11:00
futex.c Merge branch 'core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-12-30 16:10:19 -08:00
hrtimer.c hrtimers: fix warning in kernel/hrtimer.c 2008-12-19 00:45:32 +01:00
itimer.c timers: fix itimer/many thread hang 2008-09-14 16:25:35 +02:00
kallsyms.c allow stripping of generated symbols under CONFIG_KALLSYMS_ALL 2008-12-19 22:47:10 +01:00
Kconfig.freezer container freezer: implement freezer cgroup subsystem 2008-10-20 08:52:34 -07:00
Kconfig.hz sched: fix SCHED_HRTICK dependency 2008-07-28 14:37:38 +02:00
Kconfig.preempt rcu: provide RCU options on non-preempt architectures too 2008-12-25 09:31:28 +01:00
kexec.c kexec: fix crash_save_vmcoreinfo_init build problem 2008-10-20 15:28:50 -07:00
kfifo.c
kgdb.c kgdb: call touch_softlockup_watchdog on resume 2008-10-06 13:50:59 -05:00
kmod.c CRED: Inaugurate COW credentials 2008-11-14 10:39:23 +11:00
kprobes.c kernel/kprobes.c: don't pad kretprobe_table_locks[] on uniprocessor builds 2008-11-12 17:17:17 -08:00
ksysfs.c profiling: dynamically enable readprofile at runtime 2008-10-16 11:21:31 -07:00
kthread.c tracepoints: add DECLARE_TRACE() and DEFINE_TRACE() 2008-11-16 09:01:36 +01:00
latencytop.c KSYM_SYMBOL_LEN fixes 2008-12-10 08:01:54 -08:00
lockdep_internals.h lockdep: build fix 2008-08-13 12:55:10 +02:00
lockdep_proc.c lockstat: contend with points 2008-10-20 15:43:10 +02:00
lockdep.c Merge branch 'core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-12-30 16:10:19 -08:00
Makefile Merge branch 'core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-12-30 16:10:19 -08:00
marker.c markers/tracpoints: fix non-modular build 2008-11-16 09:52:03 +01:00
module.c tracing/function-graph-tracer: introduce __notrace_funcgraph to filter special functions 2008-12-08 15:11:44 +01:00
mutex-debug.c
mutex-debug.h
mutex.c mutex: __used is needed for function referenced only from inline asm 2008-11-24 10:00:28 +01:00
mutex.h
notifier.c Merge commit 'v2.6.28-rc6' into core/debug 2008-11-26 08:22:50 +01:00
ns_cgroup.c cgroup_clone: use pid of newly created task for new cgroup 2008-07-25 10:53:37 -07:00
nsproxy.c User namespaces: set of cleanups (v2) 2008-11-24 18:57:41 -05:00
panic.c Merge branch 'core/debug' into core/core 2008-12-25 13:53:11 +01:00
params.c Fix compile warning in kernel/params.c 2008-10-23 12:09:00 -07:00
pid_namespace.c pid_ns: (BUG 11391) change ->child_reaper when init->group_leader exits 2008-09-02 19:21:38 -07:00
pid.c pidns: remove now unused find_pid function. 2008-07-25 10:53:45 -07:00
pm_qos_params.c pm_qos_requirement might sleep 2008-09-02 19:21:40 -07:00
posix-cpu-timers.c Merge commit 'v2.6.28' into core/core 2008-12-25 13:51:46 +01:00
posix-timers.c Merge branches 'timers/clocksource', 'timers/hpet', 'timers/hrtimers', 'timers/nohz', 'timers/ntp', 'timers/posixtimers' and 'timers/rtc' into timers/core 2008-12-25 18:02:25 +01:00
printk.c printk: fix discarding message when recursion_bug 2008-12-19 22:52:47 +01:00
profile.c Merge commit 'v2.6.28-rc7' into tracing/core 2008-12-04 09:07:19 +01:00
ptrace.c Merge branch 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-12-28 12:21:10 -08:00
rcuclassic.c rcu: make rcu-stall debug printout more standard 2008-11-03 18:34:55 +01:00
rcupdate.c rcupdate: fix bug of rcu_barrier*() 2008-10-21 15:59:53 +02:00
rcupreempt_trace.c "Tree RCU": scalable classic RCU implementation 2008-12-18 21:56:04 +01:00
rcupreempt.c "Tree RCU": scalable classic RCU implementation 2008-12-18 21:56:04 +01:00
rcutorture.c rcu: fix rcutorture behavior during reboot 2008-12-17 00:04:40 +01:00
rcutree_trace.c "Tree RCU": scalable classic RCU implementation 2008-12-18 21:56:04 +01:00
rcutree.c "Tree RCU": scalable classic RCU implementation 2008-12-18 21:56:04 +01:00
relay.c relayfs: fix infinite loop with splice() 2008-12-10 08:01:52 -08:00
res_counter.c cgroup files: convert res_counter_write() to be a cgroups write_string() handler 2008-07-25 10:53:36 -07:00
resource.c resources: skip sanity check of busy resources 2008-12-16 23:30:49 +01:00
rtmutex_common.h
rtmutex-debug.c
rtmutex-debug.h
rtmutex-tester.c sysdev: Pass the attribute to the low level sysdev show/store function 2008-07-21 21:55:02 -07:00
rtmutex.c hrtimer: convert kernel/* to the new hrtimer apis 2008-09-05 21:35:13 -07:00
rtmutex.h
rwsem.c
sched_clock.c Revert "sched_clock: prevent scd->clock from moving backwards" 2008-12-14 16:23:17 -08:00
sched_cpupri.c
sched_cpupri.h
sched_debug.c sched: add uid information to sched_debug for CONFIG_USER_SCHED 2008-12-01 20:39:50 +01:00
sched_fair.c sched: optimize update_curr() 2008-12-16 09:46:33 +01:00
sched_features.h sched: backward looking buddy 2008-11-05 10:30:14 +01:00
sched_idletask.c sched: add CONFIG_SMP consistency 2008-10-22 10:01:52 +02:00
sched_rt.c Merge branch 'sched/urgent'; commit 'v2.6.28' into sched/core 2008-12-25 13:42:23 +01:00
sched_stats.h schedstat: consolidate per-task cpu runtime stats 2008-12-18 13:54:01 +01:00
sched.c [PATCH] idle cputime accounting 2008-12-31 15:11:46 +01:00
seccomp.c
semaphore.c semaphore: __down_common: use signal_pending_state() 2008-08-05 14:33:47 -07:00
signal.c Merge branch 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-12-28 12:21:10 -08:00
smp.c generic-ipi: fix the smp_mb() placement 2008-11-06 08:41:56 +01:00
softirq.c Merge branches 'core/debugobjects', 'core/iommu', 'core/locking', 'core/printk', 'core/rcu', 'core/resources', 'core/softirq' and 'core/stacktrace' into core/core 2008-12-25 14:06:29 +01:00
softlockup.c Merge commit 'v2.6.28' into core/core 2008-12-25 13:51:46 +01:00
spinlock.c lockdep: spin_lock_nest_lock(), checkpatch fixes 2008-08-13 13:56:51 +02:00
srcu.c
stacktrace.c stacktrace: provide save_stack_trace_tsk() weak alias 2008-12-25 11:44:43 +01:00
stop_machine.c stop_machine: fix race with return value (fixes Bug #11989) 2008-11-16 15:09:52 -08:00
sys_ni.c reintroduce accept4 2008-11-19 18:49:57 -08:00
sys.c Merge branch 'core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-12-30 16:10:19 -08:00
sysctl_check.c [XFS] remove restricted chown parameter from xfs linux 2008-10-30 18:30:09 +11:00
sysctl.c Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6 2008-12-28 20:19:47 -08:00
taskstats.c taskstats: remove initialization of static per-cpu variable 2008-07-25 10:53:47 -07:00
test_kprobes.c
time.c select: add a timespec_add_safe() function 2008-09-05 21:34:57 -07:00
timeconst.pl
timer.c [PATCH] idle cputime accounting 2008-12-31 15:11:46 +01:00
tracepoint.c markers/tracpoints: fix non-modular build 2008-11-16 09:52:03 +01:00
tsacct.c CRED: Use RCU to access another task's creds and to release a task's own creds 2008-11-14 10:39:19 +11:00
uid16.c CRED: Wrap current->cred and a few other accessors 2008-11-14 10:39:18 +11:00
user_namespace.c User namespaces: set of cleanups (v2) 2008-11-24 18:57:41 -05:00
user.c Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-12-28 12:27:58 -08:00
utsname_sysctl.c sysctl: simplify ->strategy 2008-10-16 11:21:47 -07:00
utsname.c removed unused #include <linux/version.h>'s 2008-08-23 12:14:12 -07:00
wait.c wait: kill is_sync_wait() 2008-10-16 11:21:31 -07:00
workqueue.c Merge branch 'master' into next 2008-11-14 11:29:12 +11:00