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Wed, 31 Jul 2024 03:34:00 -0700 (PDT) Received: from andrea ([151.76.3.213]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-a7acad9046fsm760828166b.147.2024.07.31.03.33.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 31 Jul 2024 03:33:59 -0700 (PDT) Date: Wed, 31 Jul 2024 12:33:54 +0200 From: Andrea Parri To: Andrew Jones Cc: Alexandre Ghiti , Jonathan Corbet , Paul Walmsley , Palmer Dabbelt , Albert Ou , Conor Dooley , Rob Herring , Krzysztof Kozlowski , Nathan Chancellor , Peter Zijlstra , Ingo Molnar , Will Deacon , Waiman Long , Boqun Feng , Arnd Bergmann , Leonardo Bras , Guo Ren , linux-doc@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, linux-arch@vger.kernel.org, Andrea Parri Subject: Re: [PATCH v4 06/13] riscv: Improve zacas fully-ordered cmpxchg() Message-ID: References: <20240731072405.197046-1-alexghiti@rivosinc.com> <20240731072405.197046-7-alexghiti@rivosinc.com> <20240731-260cce60e1a6cd06670d1b24@orel> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240731-260cce60e1a6cd06670d1b24@orel> > > amocas.X.aqrl a5,a4,(s1) > > We won't get release semantics if the exchange fails. Does that matter? Conditional (atomic) RMW operations are unordered/relaxed on failure, so we should be okay here; cf. e.g. Documentation/atomic_t.txt. Andrea