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Sun, 16 Aug 2026 03:10:44 +0000 (UTC) From: xtex To: Bingwu Zhang , Gao Xiang , Chao Yu , Yue Hu , Jeffle Xu , Sandeep Dhavale , Hongbo Li , Chunhai Guo , linux-erofs@lists.ozlabs.org, linux-kernel@vger.kernel.org, Bingwu Zhang Subject: Re: [PATCH] erofs: remove erofs_dev_context->rwsem Date: Sun, 16 Aug 2026 11:11:28 +0800 Message-ID: Organization: AstraFall In-Reply-To: References: <20260816-erofs-remove-rwsem-v1-1-78b60b855fa6@astrafall.org> X-Mailing-List: linux-erofs@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Hi, On Sunday, August 16, 2026 11:06:05=E2=80=AFAM China Standard Time Gao Xian= g wrote: > Hi Bingwu, >=20 > On Sun, Aug 16, 2026 at 10:00:12AM +0800, Bingwu Zhang wrote: > > From: Bingwu Zhang > >=20 > > devs->tree is only modified in initialization and > > destruction code paths and will never be concurrent > > with data reading. Thus there is no need to guard > > idr_alloc/idr_find with a rwsem. >=20 > Thanks for the patch. >=20 > In principle, yes, but it's also no problem to leave it as-is in case > some use cases later need adjust the device_info of a dev for example > at runtime. >=20 > Or if it causes any noticeable performance penalty, that will be one > reason to drop it now. Thanks for the reply. I don't think it caused any notice performance=20 difference so it looks good to me to keep the rwsem. Thanks, Bingwu Zhang >=20 > Thanks, > Gao Xiang >=20 > > Signed-off-by: Bingwu Zhang