Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <5e885fce-a0b4-559f-5498-4402080f6a2e@kernel.dk>
Date:   Wed, 16 Nov 2022 16:58:34 -0700
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:102.0) Gecko/20100101
 Thunderbird/102.4.1
Subject: Re: [PATCH v10 0/3] blk-cgroup: Optimize blkcg_rstat_flush()
Content-Language: en-US
To:     Waiman Long <longman@redhat.com>
Cc:     cgroups@vger.kernel.org, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, Ming Lei <ming.lei@redhat.com>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        =?UTF-8?Q?Michal_Koutn=c3=bd?= <mkoutny@suse.com>,
        Hillf Danton <hdanton@sina.com>, Tejun Heo <tj@kernel.org>
References: <20221105005902.407297-1-longman@redhat.com>
 <4b5142be-6a47-9dfd-a238-5b9d29b296b8@redhat.com>
From:   Jens Axboe <axboe@kernel.dk>
In-Reply-To: <4b5142be-6a47-9dfd-a238-5b9d29b296b8@redhat.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 11/16/22 4:06 PM, Waiman Long wrote:
> On 11/4/22 20:58, Waiman Long wrote:
>> ? v10:
>> ?? - Update patch 3 to rename the rstat function to
>> ???? cgroup_rstat_css_cpu_flush().
>>
>> ? v9:
>> ?? - Remove patch "llist: Allow optional sentinel node terminated lockless
>> ???? list" for now. This will be done as a follow-up patch.
>> ?? - Add a new lqueued field to blkg_iostat_set to store the status of
>> ???? whether lnode is in a lockless list.
>> ?? - Add a new patch 3 to speed up the freeing of blkcg by flushing out
>> ???? the rstat lockless lists at blkcg offline time.
>>
>> ? v8:
>> ?? - Update the llist patch to make existing llist functions and macros
>> ???? work for both NULL and sentinel terminated lockless list as much
>> ???? as possible and leave only the initialization and removal functions
>> ???? to have a sentinel terminated llist variants.
>>
>> This patch series improves blkcg_rstat_flush() performance by eliminating
>> unnecessary blkg enumeration and flush operations for those blkg's and
>> blkg_iostat_set's that haven't been updated since the last flush.
>>
>> Waiman Long (3):
>> ?? blk-cgroup: Return -ENOMEM directly in blkcg_css_alloc() error path
>> ?? blk-cgroup: Optimize blkcg_rstat_flush()
>> ?? blk-cgroup: Flush stats at blkgs destruction path
>>
>> ? block/blk-cgroup.c???? | 103 +++++++++++++++++++++++++++++++++++------
>> ? block/blk-cgroup.h???? |? 10 ++++
>> ? include/linux/cgroup.h |?? 1 +
>> ? kernel/cgroup/rstat.c? |? 20 ++++++++
>> ? 4 files changed, 119 insertions(+), 15 deletions(-)
> 
> Jens, do you have any further comment on this patchset? Is it possible
> to queue it for the next Linux version?

Looks good to me, I'll queue it up.

-- 
Jens Axboe