On Wed, Sep 12, 2012 at 4:22 PM, Peter Zijlstra <[email protected]> wrote: > On Wed, 2012-09-12 at 16:13 +0200, Stephane Eranian wrote: >> +static DEFINE_PER_CPU(struct list_head, rotation_list); > > Why do you keep the rotation list? The only use seems to be: > > >> +void perf_cpu_hrtimer_cancel(int cpu) >> +{ >> + struct list_head *head = &__get_cpu_var(rotation_list); >> + struct perf_cpu_context *cpuctx, *tmp; >> + unsigned long flags; >> + >> + if (WARN_ON(cpu != smp_processor_id())) >> + return; >> + >> + local_irq_save(flags); >> + >> + list_for_each_entry_safe(cpuctx, tmp, head, rotation_list) { >> + if (cpuctx->hrtimer_active) { >> + hrtimer_cancel(&cpuctx->hrtimer); >> + cpuctx->hrtimer_active = 0; >> + } >> + } >> + >> + local_irq_restore(flags); >> +} > > Which is weird, why not use the existing for-each-pmu loop in > perf_event_exit_cpu_context() ? Or something similar to iterate all > extant PMUs and thus their cpuctxs? > True. That would probably work too.
> Also, you can do away with hrtimer_active, you can hrtimer_cancel() on > an inactive hrtimer just fine, it will DTRT. The hrtimer_active is used to prevent activating the timer multiple times in a row. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
