Messages in this thread | | | Date | Mon, 30 Jun 2014 19:02:45 -0700 | From | Laura Abbott <> | Subject | Re: [RFC] CMA page migration failure due to buffers on bh_lru |
| |
On 6/30/2014 6:07 PM, Gioh Kim wrote: > Hi,Laura. > > I have a question. > > Does the __evict_bh_lru() not need bh_lru_lock()? > The get_cpu_var() has already preenpt_disable() and can prevent other thread. > But get_cpu_var cannot prevent IRQ context such like page-fault. > I think if a page-fault occured and a file is read in IRQ context it can change cpu-lru. > > Is my concern correct? > >
__evict_bh_lru is called via on_each_cpu_cond which I believe will disable irqs. I based the code on the existing invalidate_bh_lru which did not take the bh_lru_lock either. It's possible I missed something though.
Thanks, Laura
-- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation
| |