cputime: Use accessors to read task cputime stats
This is in preparation for the full dynticks feature. While
remotely reading the cputime of a task running in a full
dynticks CPU, we'll need to do some extra-computation. This
way we can account the time it spent tickless in userspace
since its last cputime snapshot.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
diff --git a/kernel/acct.c b/kernel/acct.c
index 051e071..e8b1627 100644
--- a/kernel/acct.c
+++ b/kernel/acct.c
@@ -566,6 +566,7 @@
void acct_collect(long exitcode, int group_dead)
{
struct pacct_struct *pacct = ¤t->signal->pacct;
+ cputime_t utime, stime;
unsigned long vsize = 0;
if (group_dead && current->mm) {
@@ -593,8 +594,9 @@
pacct->ac_flag |= ACORE;
if (current->flags & PF_SIGNALED)
pacct->ac_flag |= AXSIG;
- pacct->ac_utime += current->utime;
- pacct->ac_stime += current->stime;
+ task_cputime(current, &utime, &stime);
+ pacct->ac_utime += utime;
+ pacct->ac_stime += stime;
pacct->ac_minflt += current->min_flt;
pacct->ac_majflt += current->maj_flt;
spin_unlock_irq(¤t->sighand->siglock);
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 3046a50..e5d5e8e 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -224,11 +224,13 @@
static inline void check_for_tasks(int cpu)
{
struct task_struct *p;
+ cputime_t utime, stime;
write_lock_irq(&tasklist_lock);
for_each_process(p) {
+ task_cputime(p, &utime, &stime);
if (task_cpu(p) == cpu && p->state == TASK_RUNNING &&
- (p->utime || p->stime))
+ (utime || stime))
printk(KERN_WARNING "Task %s (pid = %d) is on cpu %d "
"(state = %ld, flags = %x)\n",
p->comm, task_pid_nr(p), cpu,
diff --git a/kernel/delayacct.c b/kernel/delayacct.c
index 418b3f7..d473988 100644
--- a/kernel/delayacct.c
+++ b/kernel/delayacct.c
@@ -106,6 +106,7 @@
unsigned long long t2, t3;
unsigned long flags;
struct timespec ts;
+ cputime_t utime, stime, stimescaled, utimescaled;
/* Though tsk->delays accessed later, early exit avoids
* unnecessary returning of other data
@@ -114,12 +115,14 @@
goto done;
tmp = (s64)d->cpu_run_real_total;
- cputime_to_timespec(tsk->utime + tsk->stime, &ts);
+ task_cputime(tsk, &utime, &stime);
+ cputime_to_timespec(utime + stime, &ts);
tmp += timespec_to_ns(&ts);
d->cpu_run_real_total = (tmp < (s64)d->cpu_run_real_total) ? 0 : tmp;
tmp = (s64)d->cpu_scaled_run_real_total;
- cputime_to_timespec(tsk->utimescaled + tsk->stimescaled, &ts);
+ task_cputime_scaled(tsk, &utimescaled, &stimescaled);
+ cputime_to_timespec(utimescaled + stimescaled, &ts);
tmp += timespec_to_ns(&ts);
d->cpu_scaled_run_real_total =
(tmp < (s64)d->cpu_scaled_run_real_total) ? 0 : tmp;
diff --git a/kernel/exit.c b/kernel/exit.c
index b4df219..7dd2040 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -85,6 +85,7 @@
bool group_dead = thread_group_leader(tsk);
struct sighand_struct *sighand;
struct tty_struct *uninitialized_var(tty);
+ cputime_t utime, stime;
sighand = rcu_dereference_check(tsk->sighand,
lockdep_tasklist_lock_is_held());
@@ -123,9 +124,10 @@
* We won't ever get here for the group leader, since it
* will have been the last reference on the signal_struct.
*/
- sig->utime += tsk->utime;
- sig->stime += tsk->stime;
- sig->gtime += tsk->gtime;
+ task_cputime(tsk, &utime, &stime);
+ sig->utime += utime;
+ sig->stime += stime;
+ sig->gtime += task_gtime(tsk);
sig->min_flt += tsk->min_flt;
sig->maj_flt += tsk->maj_flt;
sig->nvcsw += tsk->nvcsw;
@@ -1092,7 +1094,7 @@
sig = p->signal;
psig->cutime += tgutime + sig->cutime;
psig->cstime += tgstime + sig->cstime;
- psig->cgtime += p->gtime + sig->gtime + sig->cgtime;
+ psig->cgtime += task_gtime(p) + sig->gtime + sig->cgtime;
psig->cmin_flt +=
p->min_flt + sig->min_flt + sig->cmin_flt;
psig->cmaj_flt +=
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index a278cad..165d476 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -155,11 +155,19 @@
static inline cputime_t prof_ticks(struct task_struct *p)
{
- return p->utime + p->stime;
+ cputime_t utime, stime;
+
+ task_cputime(p, &utime, &stime);
+
+ return utime + stime;
}
static inline cputime_t virt_ticks(struct task_struct *p)
{
- return p->utime;
+ cputime_t utime;
+
+ task_cputime(p, &utime, NULL);
+
+ return utime;
}
static int
@@ -471,18 +479,23 @@
*/
void posix_cpu_timers_exit(struct task_struct *tsk)
{
+ cputime_t utime, stime;
+
add_device_randomness((const void*) &tsk->se.sum_exec_runtime,
sizeof(unsigned long long));
+ task_cputime(tsk, &utime, &stime);
cleanup_timers(tsk->cpu_timers,
- tsk->utime, tsk->stime, tsk->se.sum_exec_runtime);
+ utime, stime, tsk->se.sum_exec_runtime);
}
void posix_cpu_timers_exit_group(struct task_struct *tsk)
{
struct signal_struct *const sig = tsk->signal;
+ cputime_t utime, stime;
+ task_cputime(tsk, &utime, &stime);
cleanup_timers(tsk->signal->cpu_timers,
- tsk->utime + sig->utime, tsk->stime + sig->stime,
+ utime + sig->utime, stime + sig->stime,
tsk->se.sum_exec_runtime + sig->sum_sched_runtime);
}
@@ -1226,11 +1239,14 @@
static inline int fastpath_timer_check(struct task_struct *tsk)
{
struct signal_struct *sig;
+ cputime_t utime, stime;
+
+ task_cputime(tsk, &utime, &stime);
if (!task_cputime_zero(&tsk->cputime_expires)) {
struct task_cputime task_sample = {
- .utime = tsk->utime,
- .stime = tsk->stime,
+ .utime = utime,
+ .stime = stime,
.sum_exec_runtime = tsk->se.sum_exec_runtime
};
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index e1939d3..c533dea 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -164,7 +164,7 @@
task_group_account_field(p, index, (__force u64) cputime);
/* Account for user time used */
- acct_update_integrals(p);
+ acct_account_cputime(p);
}
/*
@@ -214,7 +214,7 @@
task_group_account_field(p, index, (__force u64) cputime);
/* Account for system time used */
- acct_update_integrals(p);
+ acct_account_cputime(p);
}
/*
@@ -296,6 +296,7 @@
void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times)
{
struct signal_struct *sig = tsk->signal;
+ cputime_t utime, stime;
struct task_struct *t;
times->utime = sig->utime;
@@ -309,8 +310,9 @@
t = tsk;
do {
- times->utime += t->utime;
- times->stime += t->stime;
+ task_cputime(tsk, &utime, &stime);
+ times->utime += utime;
+ times->stime += stime;
times->sum_exec_runtime += task_sched_runtime(t);
} while_each_thread(tsk, t);
out:
@@ -588,11 +590,10 @@
void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st)
{
struct task_cputime cputime = {
- .utime = p->utime,
- .stime = p->stime,
.sum_exec_runtime = p->se.sum_exec_runtime,
};
+ task_cputime(p, &cputime.utime, &cputime.stime);
cputime_adjust(&cputime, &p->prev_cputime, ut, st);
}
diff --git a/kernel/signal.c b/kernel/signal.c
index 372771e..776a45a 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1638,6 +1638,7 @@
unsigned long flags;
struct sighand_struct *psig;
bool autoreap = false;
+ cputime_t utime, stime;
BUG_ON(sig == -1);
@@ -1675,8 +1676,9 @@
task_uid(tsk));
rcu_read_unlock();
- info.si_utime = cputime_to_clock_t(tsk->utime + tsk->signal->utime);
- info.si_stime = cputime_to_clock_t(tsk->stime + tsk->signal->stime);
+ task_cputime(tsk, &utime, &stime);
+ info.si_utime = cputime_to_clock_t(utime + tsk->signal->utime);
+ info.si_stime = cputime_to_clock_t(stime + tsk->signal->stime);
info.si_status = tsk->exit_code & 0x7f;
if (tsk->exit_code & 0x80)
@@ -1740,6 +1742,7 @@
unsigned long flags;
struct task_struct *parent;
struct sighand_struct *sighand;
+ cputime_t utime, stime;
if (for_ptracer) {
parent = tsk->parent;
@@ -1758,8 +1761,9 @@
info.si_uid = from_kuid_munged(task_cred_xxx(parent, user_ns), task_uid(tsk));
rcu_read_unlock();
- info.si_utime = cputime_to_clock_t(tsk->utime);
- info.si_stime = cputime_to_clock_t(tsk->stime);
+ task_cputime(tsk, &utime, &stime);
+ info.si_utime = cputime_to_clock_t(utime);
+ info.si_stime = cputime_to_clock_t(stime);
info.si_code = why;
switch (why) {
diff --git a/kernel/tsacct.c b/kernel/tsacct.c
index 625df0b..a1dd9a1 100644
--- a/kernel/tsacct.c
+++ b/kernel/tsacct.c
@@ -32,6 +32,7 @@
{
const struct cred *tcred;
struct timespec uptime, ts;
+ cputime_t utime, stime, utimescaled, stimescaled;
u64 ac_etime;
BUILD_BUG_ON(TS_COMM_LEN < TASK_COMM_LEN);
@@ -65,10 +66,15 @@
stats->ac_ppid = pid_alive(tsk) ?
task_tgid_nr_ns(rcu_dereference(tsk->real_parent), pid_ns) : 0;
rcu_read_unlock();
- stats->ac_utime = cputime_to_usecs(tsk->utime);
- stats->ac_stime = cputime_to_usecs(tsk->stime);
- stats->ac_utimescaled = cputime_to_usecs(tsk->utimescaled);
- stats->ac_stimescaled = cputime_to_usecs(tsk->stimescaled);
+
+ task_cputime(tsk, &utime, &stime);
+ stats->ac_utime = cputime_to_usecs(utime);
+ stats->ac_stime = cputime_to_usecs(stime);
+
+ task_cputime_scaled(tsk, &utimescaled, &stimescaled);
+ stats->ac_utimescaled = cputime_to_usecs(utimescaled);
+ stats->ac_stimescaled = cputime_to_usecs(stimescaled);
+
stats->ac_minflt = tsk->min_flt;
stats->ac_majflt = tsk->maj_flt;
@@ -115,11 +121,8 @@
#undef KB
#undef MB
-/**
- * acct_update_integrals - update mm integral fields in task_struct
- * @tsk: task_struct for accounting
- */
-void acct_update_integrals(struct task_struct *tsk)
+static void __acct_update_integrals(struct task_struct *tsk,
+ cputime_t utime, cputime_t stime)
{
if (likely(tsk->mm)) {
cputime_t time, dtime;
@@ -128,7 +131,7 @@
u64 delta;
local_irq_save(flags);
- time = tsk->stime + tsk->utime;
+ time = stime + utime;
dtime = time - tsk->acct_timexpd;
jiffies_to_timeval(cputime_to_jiffies(dtime), &value);
delta = value.tv_sec;
@@ -145,6 +148,27 @@
}
/**
+ * acct_update_integrals - update mm integral fields in task_struct
+ * @tsk: task_struct for accounting
+ */
+void acct_update_integrals(struct task_struct *tsk)
+{
+ cputime_t utime, stime;
+
+ task_cputime(tsk, &utime, &stime);
+ __acct_update_integrals(tsk, utime, stime);
+}
+
+/**
+ * acct_account_cputime - update mm integral after cputime update
+ * @tsk: task_struct for accounting
+ */
+void acct_account_cputime(struct task_struct *tsk)
+{
+ __acct_update_integrals(tsk, tsk->utime, tsk->stime);
+}
+
+/**
* acct_clear_integrals - clear the mm integral fields in task_struct
* @tsk: task_struct whose accounting fields are cleared
*/
