From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Subject: Re: [PATCH v9 3/3] blk-cgroup: Flush stats at blkgs destruction path
Date: Fri, 4 Nov 2022 10:13:12 -1000
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To: Waiman Long <longman-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
Cc: Jens Axboe <axboe-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org>, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-block-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Ming Lei <ming.lei-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Andy Shevchenko <andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>, Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>, Michal =?iso-8859-1?Q?Koutn=FD?= <mkoutny-IBi9RG/b67k@public.gmane.org>, Hillf Danton <hdanton-k+cT0dCbe1g@public.gmane.org>

On Fri, Nov 04, 2022 at 04:12:05PM -0400, Waiman Long wrote:
> I should have named the function cgroup_rstat_css_cpu_flush() to indicate
> that the cpu is a needed parameter. We can have a cgroup_rstat_css_flush()
> in the future if the need arises.
> 
> It is an optimization to call this function only if the corresponding cpu
> has a pending lockless list. I could do cpu iteration here and call the
> flushing function for all the CPUs. It is less optimized this way. Since it
> is a slow path, I guess performance is not that critical. So I can go either
> way. Please let me know your preference.

Yeah, cpu_flush is fine. Let's leave it that way.

Thanks.

-- 
tejun