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Biederman" , Ying Huang , , , , , , , , , , , Subject: Re: [PATCH v4 1/4] mm: reduce the rcu lock duration Message-Id: <20220617172316.de2d41877e86be344052b9f5@linux-foundation.org> In-Reply-To: References: <20220530113016.16663-1-linmiaohe@huawei.com> <20220530113016.16663-2-linmiaohe@huawei.com> <87bkvdfzvm.fsf@email.froward.int.ebiederm.org> <87y1yga1r2.fsf@email.froward.int.ebiederm.org> <87ilph90dx.fsf@email.froward.int.ebiederm.org> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-9.3 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,NICE_REPLY_A,RCVD_IN_DNSWL_HI, SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 7 Jun 2022 17:19:53 +0800 Miaohe Lin wrote: > > > > > > If the checks are not made to guarantee they are all checking against > > the same mm, the code needs a comment to say that there is a tiny race. > > The comment should say we don't care about the tiny race because > > the worst that can happen is that a page is migrated to a different > > numa node. And so we don't care. > > > > > > I tend to do this one. To make sure, is the below code change what you suggest? Eric went quiet. As I understand it, any changes arising from this discussion can be done as a followup patch. So I'm planning on moving this 4-patch series into the non-rebasing mm-stable branch late next week.