[PATCH] fix scaled & unscaled cputime accounting
The utimescaled / stimescaled fields in the task structure and the
global cpustat should be set on all architectures. On s390 the calls
to account_user_time_scaled and account_system_time_scaled never have
been added. In addition system time that is accounted as guest time
to the user time of a process is accounted to the scaled system time
instead of the scaled user time.
To fix the bugs and to prevent future forgetfulness this patch merges
account_system_time_scaled into account_system_time and
account_user_time_scaled into account_user_time.
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Michael Neuling <mikey@neuling.org>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/ia64/kernel/time.c b/arch/ia64/kernel/time.c
index 65c10a4..4ee3678 100644
--- a/arch/ia64/kernel/time.c
+++ b/arch/ia64/kernel/time.c
@@ -93,13 +93,11 @@
now = ia64_get_itc();
delta_stime = cycle_to_cputime(pi->ac_stime + (now - pi->ac_stamp));
- account_system_time(prev, 0, delta_stime);
- account_system_time_scaled(prev, delta_stime);
+ account_system_time(prev, 0, delta_stime, delta_stime);
if (pi->ac_utime) {
delta_utime = cycle_to_cputime(pi->ac_utime);
- account_user_time(prev, delta_utime);
- account_user_time_scaled(prev, delta_utime);
+ account_user_time(prev, delta_utime, delta_utime);
}
pi->ac_stamp = ni->ac_stamp = now;
@@ -122,8 +120,7 @@
now = ia64_get_itc();
delta_stime = cycle_to_cputime(ti->ac_stime + (now - ti->ac_stamp));
- account_system_time(tsk, 0, delta_stime);
- account_system_time_scaled(tsk, delta_stime);
+ account_system_time(tsk, 0, delta_stime, delta_stime);
ti->ac_stime = 0;
ti->ac_stamp = now;
@@ -143,8 +140,7 @@
if (ti->ac_utime) {
delta_utime = cycle_to_cputime(ti->ac_utime);
- account_user_time(p, delta_utime);
- account_user_time_scaled(p, delta_utime);
+ account_user_time(p, delta_utime, delta_utime);
ti->ac_utime = 0;
}
}
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index e1f3a51..92650cc 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -256,8 +256,7 @@
delta += sys_time;
get_paca()->system_time = 0;
}
- account_system_time(tsk, 0, delta);
- account_system_time_scaled(tsk, deltascaled);
+ account_system_time(tsk, 0, delta, deltascaled);
per_cpu(cputime_last_delta, smp_processor_id()) = delta;
per_cpu(cputime_scaled_last_delta, smp_processor_id()) = deltascaled;
local_irq_restore(flags);
@@ -275,10 +274,8 @@
utime = get_paca()->user_time;
get_paca()->user_time = 0;
- account_user_time(tsk, utime);
-
utimescaled = cputime_to_scaled(utime);
- account_user_time_scaled(tsk, utimescaled);
+ account_user_time(tsk, utime, utimescaled);
}
/*
diff --git a/arch/s390/kernel/vtime.c b/arch/s390/kernel/vtime.c
index 75a6e62..07283ae 100644
--- a/arch/s390/kernel/vtime.c
+++ b/arch/s390/kernel/vtime.c
@@ -50,12 +50,12 @@
rcu_user_flag = cputime != 0;
S390_lowcore.user_timer -= cputime << 12;
S390_lowcore.steal_clock -= cputime << 12;
- account_user_time(tsk, cputime);
+ account_user_time(tsk, cputime, cputime);
cputime = S390_lowcore.system_timer >> 12;
S390_lowcore.system_timer -= cputime << 12;
S390_lowcore.steal_clock -= cputime << 12;
- account_system_time(tsk, HARDIRQ_OFFSET, cputime);
+ account_system_time(tsk, HARDIRQ_OFFSET, cputime, cputime);
cputime = S390_lowcore.steal_clock;
if ((__s64) cputime > 0) {
@@ -82,12 +82,12 @@
cputime = S390_lowcore.user_timer >> 12;
S390_lowcore.user_timer -= cputime << 12;
S390_lowcore.steal_clock -= cputime << 12;
- account_user_time(tsk, cputime);
+ account_user_time(tsk, cputime, cputime);
cputime = S390_lowcore.system_timer >> 12;
S390_lowcore.system_timer -= cputime << 12;
S390_lowcore.steal_clock -= cputime << 12;
- account_system_time(tsk, 0, cputime);
+ account_system_time(tsk, 0, cputime, cputime);
}
/*
@@ -107,7 +107,7 @@
cputime = S390_lowcore.system_timer >> 12;
S390_lowcore.system_timer -= cputime << 12;
S390_lowcore.steal_clock -= cputime << 12;
- account_system_time(tsk, 0, cputime);
+ account_system_time(tsk, 0, cputime, cputime);
}
EXPORT_SYMBOL_GPL(account_system_vtime);
diff --git a/include/linux/kernel_stat.h b/include/linux/kernel_stat.h
index 4ee4b3d..c78a459 100644
--- a/include/linux/kernel_stat.h
+++ b/include/linux/kernel_stat.h
@@ -79,10 +79,8 @@
}
extern unsigned long long task_delta_exec(struct task_struct *);
-extern void account_user_time(struct task_struct *, cputime_t);
-extern void account_user_time_scaled(struct task_struct *, cputime_t);
-extern void account_system_time(struct task_struct *, int, cputime_t);
-extern void account_system_time_scaled(struct task_struct *, cputime_t);
+extern void account_user_time(struct task_struct *, cputime_t, cputime_t);
+extern void account_system_time(struct task_struct *, int, cputime_t, cputime_t);
extern void account_steal_time(struct task_struct *, cputime_t);
#endif /* _LINUX_KERNEL_STAT_H */
diff --git a/kernel/sched.c b/kernel/sched.c
index fff1c4a..5b03679 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -4080,13 +4080,17 @@
* Account user cpu time to a process.
* @p: the process that the cpu time gets accounted to
* @cputime: the cpu time spent in user space since the last update
+ * @cputime_scaled: cputime scaled by cpu frequency
*/
-void account_user_time(struct task_struct *p, cputime_t cputime)
+void account_user_time(struct task_struct *p, cputime_t cputime,
+ cputime_t cputime_scaled)
{
struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat;
cputime64_t tmp;
+ /* Add user time to process. */
p->utime = cputime_add(p->utime, cputime);
+ p->utimescaled = cputime_add(p->utimescaled, cputime_scaled);
account_group_user_time(p, cputime);
/* Add user time to cpustat. */
@@ -4103,51 +4107,49 @@
* Account guest cpu time to a process.
* @p: the process that the cpu time gets accounted to
* @cputime: the cpu time spent in virtual machine since the last update
+ * @cputime_scaled: cputime scaled by cpu frequency
*/
-static void account_guest_time(struct task_struct *p, cputime_t cputime)
+static void account_guest_time(struct task_struct *p, cputime_t cputime,
+ cputime_t cputime_scaled)
{
cputime64_t tmp;
struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat;
tmp = cputime_to_cputime64(cputime);
+ /* Add guest time to process. */
p->utime = cputime_add(p->utime, cputime);
+ p->utimescaled = cputime_add(p->utimescaled, cputime_scaled);
account_group_user_time(p, cputime);
p->gtime = cputime_add(p->gtime, cputime);
+ /* Add guest time to cpustat. */
cpustat->user = cputime64_add(cpustat->user, tmp);
cpustat->guest = cputime64_add(cpustat->guest, tmp);
}
/*
- * Account scaled user cpu time to a process.
- * @p: the process that the cpu time gets accounted to
- * @cputime: the cpu time spent in user space since the last update
- */
-void account_user_time_scaled(struct task_struct *p, cputime_t cputime)
-{
- p->utimescaled = cputime_add(p->utimescaled, cputime);
-}
-
-/*
* Account system cpu time to a process.
* @p: the process that the cpu time gets accounted to
* @hardirq_offset: the offset to subtract from hardirq_count()
* @cputime: the cpu time spent in kernel space since the last update
+ * @cputime_scaled: cputime scaled by cpu frequency
*/
void account_system_time(struct task_struct *p, int hardirq_offset,
- cputime_t cputime)
+ cputime_t cputime, cputime_t cputime_scaled)
{
struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat;
struct rq *rq = this_rq();
cputime64_t tmp;
if ((p->flags & PF_VCPU) && (irq_count() - hardirq_offset == 0)) {
- account_guest_time(p, cputime);
+ account_guest_time(p, cputime, cputime_scaled);
return;
}
+ /* Add system time to process. */
p->stime = cputime_add(p->stime, cputime);
+ p->stimescaled = cputime_add(p->stimescaled, cputime_scaled);
account_group_system_time(p, cputime);
/* Add system time to cpustat. */
@@ -4167,17 +4169,6 @@
}
/*
- * Account scaled system cpu time to a process.
- * @p: the process that the cpu time gets accounted to
- * @hardirq_offset: the offset to subtract from hardirq_count()
- * @cputime: the cpu time spent in kernel space since the last update
- */
-void account_system_time_scaled(struct task_struct *p, cputime_t cputime)
-{
- p->stimescaled = cputime_add(p->stimescaled, cputime);
-}
-
-/*
* Account for involuntary wait time.
* @p: the process from which the cpu time has been stolen
* @steal: the cpu time spent in involuntary wait
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 8f3fc25..1f2fce2 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -420,6 +420,7 @@
int cpu = smp_processor_id();
struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu);
unsigned long ticks;
+ cputime_t cputime;
ktime_t now;
local_irq_disable();
@@ -452,8 +453,8 @@
*/
if (ticks && ticks < LONG_MAX) {
add_preempt_count(HARDIRQ_OFFSET);
- account_system_time(current, HARDIRQ_OFFSET,
- jiffies_to_cputime(ticks));
+ cputime = jiffies_to_cputime(ticks);
+ account_system_time(current, HARDIRQ_OFFSET, cputime, cputime);
sub_preempt_count(HARDIRQ_OFFSET);
}
diff --git a/kernel/timer.c b/kernel/timer.c
index 566257d..b5efb52 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -1023,13 +1023,11 @@
{
cputime_t one_jiffy = jiffies_to_cputime(1);
- if (user_tick) {
- account_user_time(p, one_jiffy);
- account_user_time_scaled(p, cputime_to_scaled(one_jiffy));
- } else {
- account_system_time(p, HARDIRQ_OFFSET, one_jiffy);
- account_system_time_scaled(p, cputime_to_scaled(one_jiffy));
- }
+ if (user_tick)
+ account_user_time(p, one_jiffy, cputime_to_scaled(one_jiffy));
+ else
+ account_system_time(p, HARDIRQ_OFFSET, one_jiffy,
+ cputime_to_scaled(one_jiffy));
}
#endif