Messages in this thread | | | Subject | Re: [PATCH 2/2] block: Convert BDI proportion calculations to flexible proportions | From | Peter Zijlstra <> | Date | Fri, 01 Jun 2012 00:26:05 +0200 |
| |
On Fri, 2012-06-01 at 00:11 +0200, Jan Kara wrote: > bool fprop_new_period(struct fprop_global *p, int periods) > { > - u64 events = percpu_counter_sum(&p->events); > + u64 events; > + unsigned long flags; > > + local_irq_save(flags); > + events = percpu_counter_sum(&p->events); > + local_irq_restore(flags); > /* > * Don't do anything if there are no events. > */ > @@ -73,7 +77,9 @@ bool fprop_new_period(struct fprop_global *p, int periods) > if (periods < 64) > events -= events >> periods; > /* Use addition to avoid losing events happening between sum and set */ > + local_irq_save(flags); > percpu_counter_add(&p->events, -events); > + local_irq_restore(flags); > p->period += periods; > write_seqcount_end(&p->sequence);
Uhm, why bother enabling it in between? Just wrap the whole function in a single IRQ disable.
| |