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Thu, 6 Aug 2026 17:15:26 +0000 (UTC) Message-ID: <9d9092bc-6bf0-4afb-9d1a-5ee16c9c501e@acm.org> Date: Thu, 6 Aug 2026 10:15:25 -0700 X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Archive: , List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] scsi: core: Drop Scsi_Host.default_lock To: John Garry , James.Bottomley@HansenPartnership.com, martin.petersen@oracle.com Cc: linux-scsi@vger.kernel.org, linux-s390@vger.kernel.org, linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-usb@vger.kernel.org, John Garry References: <20260806113958.3127942-1-john.g.garry@oracle.com> Content-Language: en-US From: Bart Van Assche In-Reply-To: <20260806113958.3127942-1-john.g.garry@oracle.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 8/6/26 4:39 AM, John Garry wrote: > Getting the address of embedded host_lock structure just requires adding > a fixed offset value to the shost pointer. However, getting the value of > the host_lock pointer requires loading from a fixed offset to the shost > pointer. The latter should be very slightly slower, which is relevant as > this lock is used a lot throughout the core code and drivers. Hmm ... SCSI drivers for which performance matters shouldn't use the SCSI host lock in their hot path. > @Bart, Can you kindly build test this? s390 and sh were causing some build > issues for me. Thanks This patch passes my build tests, but an update for the references to default_lock in the Documentation/ directory is missing. Otherwise this patch looks good to me. So with or without the Documentation/ update, feel free to add: Reviewed-by: Bart Van Assche