On Mon, May 07, 2018 at 05:01:34PM -0400, Johannes Weiner wrote: > +/** > + * psi_memstall_enter - mark the beginning of a memory stall section > + * @flags: flags to handle nested sections > + * > + * Marks the calling task as being stalled due to a lack of memory, > + * such as waiting for a refault or performing reclaim. > + */ > +void psi_memstall_enter(unsigned long *flags) > +{ > + struct rq_flags rf; > + struct rq *rq; > + > + *flags = current->flags & PF_MEMSTALL; > + if (*flags) > + return; > + /* > + * PF_MEMSTALL setting & accounting needs to be atomic wrt > + * changes to the task's scheduling state, otherwise we can > + * race with CPU migration. > + */ > + local_irq_disable(); > + rq = this_rq(); > + raw_spin_lock(&rq->lock); > + rq_pin_lock(rq, &rf); Given that churn in sched.h, you seen rq_lock() and friends. Either write this like: local_irq_disable(); rq = this_rq(); rq_lock(rq, &rf); Or instroduce "rq = this_rq_lock_irq()", which we could also use in do_sched_yield(). > + update_rq_clock(rq); > + > + current->flags |= PF_MEMSTALL; > + psi_task_change(current, rq_clock(rq), 0, TSK_MEMSTALL); > + > + rq_unpin_lock(rq, &rf); > + raw_spin_unlock(&rq->lock); > + local_irq_enable(); That's called rq_unlock_irq(). > +} > + > +/** > + * psi_memstall_leave - mark the end of an memory stall section > + * @flags: flags to handle nested memdelay sections > + * > + * Marks the calling task as no longer stalled due to lack of memory. > + */ > +void psi_memstall_leave(unsigned long *flags) > +{ > + struct rq_flags rf; > + struct rq *rq; > + > + if (*flags) > + return; > + /* > + * PF_MEMSTALL clearing & accounting needs to be atomic wrt > + * changes to the task's scheduling state, otherwise we could > + * race with CPU migration. > + */ > + local_irq_disable(); > + rq = this_rq(); > + raw_spin_lock(&rq->lock); > + rq_pin_lock(rq, &rf); > + > + update_rq_clock(rq); > + > + current->flags &= ~PF_MEMSTALL; > + psi_task_change(current, rq_clock(rq), TSK_MEMSTALL, 0); > + > + rq_unpin_lock(rq, &rf); > + raw_spin_unlock(&rq->lock); > + local_irq_enable(); > +} Idem. -- To unsubscribe from this list: send the line "unsubscribe cgroups" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html