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[2603:800c:1a02:1bae:e24f:43ff:fee6:449f]) by smtp.gmail.com with ESMTPSA id 68-20020a621647000000b004fa763ef1easm11159917pfw.125.2022.03.21.09.46.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 21 Mar 2022 09:46:55 -0700 (PDT) Sender: Tejun Heo Date: Mon, 21 Mar 2022 06:46:53 -1000 From: Tejun Heo To: Al Viro Cc: Imran Khan , gregkh@linuxfoundation.org, akpm@linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [RESEND PATCH v7 7/8] kernfs: Replace per-fs rwsem with hashed rwsems. Message-ID: References: <20220317072612.163143-1-imran.f.khan@oracle.com> <20220317072612.163143-8-imran.f.khan@oracle.com> <536f2392-45d2-2f43-5e9d-01ef50e33126@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RDNS_NONE,SPF_HELO_NONE, T_SCC_BODY_TEXT_LINE autolearn=no 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 Mon, Mar 21, 2022 at 07:29:45AM +0000, Al Viro wrote: ... > stabilizing the tree topology. Turn it into rwlock if you wish, > with that thing being a reader and existing users - writers. > And don't bother with further scaling, until and unless you see a real > contention on it. Given how rare these renames are, in the (unlikely) case the rename rwsem becomes a problem, we should probably just switch it to a percpu_rwsem. Thanks. -- tejun