Currently we protect 64bit sum_exec_runtime read on 32bit cpus using task_rq_lock() which internally takes t->pi_lock and rq->lock. Taking rq->lock is not needed in this case.
Signed-off-by: Stanislaw Gruszka <[email protected]> --- kernel/sched/cputime.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c index b93c72d..5535774 100644 --- a/kernel/sched/cputime.c +++ b/kernel/sched/cputime.c @@ -315,12 +315,11 @@ static inline u64 read_sum_exec_runtime(struct task_struct *t) static u64 read_sum_exec_runtime(struct task_struct *t) { u64 ns; - struct rq_flags rf; - struct rq *rq; + unsigned long flags; - rq = task_rq_lock(t, &rf); + raw_spin_lock_irqsave(&t->pi_lock, flags); ns = t->se.sum_exec_runtime; - task_rq_unlock(rq, t, &rf); + raw_spin_unlock_irqrestore(&t->pi_lock, flags); return ns; } -- 1.8.3.1
