Messages in this thread | | | Date | Fri, 26 Jun 2015 09:45:25 -0400 | From | Vivek Goyal <> | Subject | Re: [PATCH 2/6] blkcg: add blkg_[rw]stat->aux_cnt and replace cfq_group->dead_stats with it |
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On Fri, Jun 26, 2015 at 09:35:40AM -0400, Tejun Heo wrote: > On Fri, Jun 26, 2015 at 09:27:02AM -0400, Vivek Goyal wrote: > > On Thu, Jun 25, 2015 at 05:38:53PM -0400, Tejun Heo wrote: > > > > [..] > > > It's planned that the core stats will be moved to blkcg_gq, so we want > > > to move the mechanism for keeping track of the stats of dead children > > > from cfq to blkcg core. This patch adds blkg_[rw]stat->aux_cnt which > > > are atomic64_t's keeping track of auxiliary counts which are excluded > > > when reading local counts but included for recursive. > > > > Hi Tejun, > > > > So aux_cnt is atomic64_t as updation is not the hot path hence there is > > not much value in keeping it as per cpu? > > I'm not following. aux_cnt isn't per-cpu.
I was just curious that why aux_cnt is different from rest of the stats. (It is atomic64_t while others are not).
Thanks Vivek
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