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To: Michal Hocko Cc: akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, wuyun.abel@bytedance.com References: <20221204161432.2149375-1-hezhongkun.hzk@bytedance.com> From: Zhongkun He In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 9F528C0010 X-Stat-Signature: k3aro1x5i3spfyxh1w4ygdbixizh5ds1 X-HE-Tag: 1673712624-302436 X-HE-Meta: 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 9zOmcWHt x+BcMG6T1iEQaG0pH+jca2e0NZLta6hbOJyPvMa/6sFcDXluwlMMymbpx6/pRp4YOAeM8wUlWSIOnQ2x8V5T+dOTslaME3u3pEN99YpIqzkQsvXlW1I+YIVxUc8NAoBhs+uW58H0fh55iBflYI+GzIbtEux68TMN3hqvZufhPlMJGDI6MJ7H7HG7WiqTMoX73EtaM1VXEYaNJKRvdx6pnNnwi5A== X-Bogosity: Ham, tests=bogofilter, spamicity=0.003178, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: > On Fri 13-01-23 17:20:39, Michal Hocko wrote: >> >> This is really hard to follow. Without having the context from previous >> discussions I would be completely lost. Please structure your cover >> letter but also other patch in general in the form: >> - what is the problem you would like to deal with >> - want to introduce pidfd_set_mempolicy because XYZ >> - what stands in the way >> - mempolicy objects access constrains (reliance on operating in >> the current context) >> - reference counting needs to be unconditional >> - why regular reference counting is not sufficient (performance) >> - what is this patchset proposing >> - per cpu reference counting >> - how is it implemented >> - how is the patch series structured >> - make the reference counting unconditional >> - special case static (never released) policies >> - replace standard ref counting by per-cpu reference counting > - introduce pidfd_set_mempolicy >> - how has this been tested? Hi Michal, thanks for your review and suggestions. I will follow the advice above to structure the letter and split the patches smaller on next version. Thanks.