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>

1 files changed, 7 insertions, 6 deletions

diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index e1939d38bf73..c533deaf06d5 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -164,7 +164,7 @@ void account_user_time(struct task_struct *p, cputime_t cputime,
         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 @@ void __account_system_time(struct task_struct *p, cputime_t cputime,
         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 @@ static __always_inline bool steal_account_process_tick(void)
 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 @@ void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times)
 
         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 @@ static void cputime_adjust(struct task_cputime *curr,
 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);
 }