On Thu, 29 May 2014 15:22:34 +0900 Joonsoo Kim <iamjoonsoo....@lge.com> wrote:
> Richard Yao reported a month ago that his system have a trouble > with vmap_area_lock contention during performance analysis > by /proc/meminfo. Andrew asked why his analysis checks /proc/meminfo > stressfully, but he didn't answer it. > > https://lkml.org/lkml/2014/4/10/416 > > Although I'm not sure that this is right usage or not, there is a solution > reducing vmap_area_lock contention with no side-effect. That is just > to use rcu list iterator in get_vmalloc_info(). This function only needs > values on vmap_area structure, so we don't need to grab a spinlock. The mixture of rcu protection and spinlock protection for vmap_area_list is pretty confusing. Are you able to describe the overall design here? When and why do we use one versus the other? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
