[PATCH RESEND 06/36] cputime: Convert guest time accounting to nsecs

Frederic Weisbecker
2017-01-31T03:18:21Z

cputime_t is being obsolete and replaced by nsecs units in order to make
internal timestamps less opaque and more granular.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
---
fs/proc/array.c | 6 +++---
include/linux/sched.h | 10 +++++-----
kernel/sched/cputime.c | 8 ++++----
3 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/fs/proc/array.c b/fs/proc/array.c
index 51a4213..25b54cf 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -402,7 +402,7 @@ static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
unsigned long cmin_flt = 0, cmaj_flt = 0;
unsigned long min_flt = 0, maj_flt = 0;
cputime_t cutime, cstime, utime, stime;
- cputime_t cgtime, gtime;
+ u64 cgtime, gtime;
unsigned long rsslim = 0;
char tcomm[sizeof(task->comm)];
unsigned long flags;
@@ -542,8 +542,8 @@ static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
seq_put_decimal_ull(m, " ", task->rt_priority);
seq_put_decimal_ull(m, " ", task->policy);
seq_put_decimal_ull(m, " ", delayacct_blkio_ticks(task));
- seq_put_decimal_ull(m, " ", cputime_to_clock_t(gtime));
- seq_put_decimal_ll(m, " ", cputime_to_clock_t(cgtime));
+ seq_put_decimal_ull(m, " ", nsec_to_clock_t(gtime));
+ seq_put_decimal_ll(m, " ", nsec_to_clock_t(cgtime));

if (mm && permitted) {
seq_put_decimal_ull(m, " ", mm->start_data);
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 5f60aed..252ff25 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -774,8 +774,8 @@ struct signal_struct {
*/
seqlock_t stats_lock;
cputime_t utime, stime, cutime, cstime;
- cputime_t gtime;
- cputime_t cgtime;
+ u64 gtime;
+ u64 cgtime;
struct prev_cputime prev_cputime;
unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
@@ -1658,7 +1658,7 @@ struct task_struct {
#ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
cputime_t utimescaled, stimescaled;
#endif
- cputime_t gtime;
+ u64 gtime;
struct prev_cputime prev_cputime;
#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
seqcount_t vtime_seqcount;
@@ -2254,7 +2254,7 @@ struct task_struct *try_get_task_struct(struct task_struct **ptask);
#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
extern void task_cputime(struct task_struct *t,
cputime_t *utime, cputime_t *stime);
-extern cputime_t task_gtime(struct task_struct *t);
+extern u64 task_gtime(struct task_struct *t);
#else
static inline void task_cputime(struct task_struct *t,
cputime_t *utime, cputime_t *stime)
@@ -2263,7 +2263,7 @@ static inline void task_cputime(struct task_struct *t,
*stime = t->stime;
}

-static inline cputime_t task_gtime(struct task_struct *t)
+static inline u64 task_gtime(struct task_struct *t)
{
return t->gtime;
}
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index 61e2709..8bcd98e 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -158,7 +158,7 @@ void account_guest_time(struct task_struct *p, cputime_t cputime)
/* Add guest time to process. */
p->utime += cputime;
account_group_user_time(p, cputime);
- p->gtime += cputime;
+ p->gtime += cputime_to_nsecs(cputime);

/* Add guest time to cpustat. */
if (task_nice(p) > 0) {
@@ -824,10 +824,10 @@ void vtime_init_idle(struct task_struct *t, int cpu)
local_irq_restore(flags);
}

-cputime_t task_gtime(struct task_struct *t)
+u64 task_gtime(struct task_struct *t)
{
unsigned int seq;
- cputime_t gtime;
+ u64 gtime;

if (!vtime_accounting_enabled())
return t->gtime;
@@ -837,7 +837,7 @@ cputime_t task_gtime(struct task_struct *t)

gtime = t->gtime;
if (t->vtime_snap_whence == VTIME_SYS && t->flags & PF_VCPU)
- gtime += vtime_delta(t);
+ gtime += cputime_to_nsecs(vtime_delta(t));

} while (read_seqcount_retry(&t->vtime_seqcount, seq));

--
2.7.4