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Peter Anvin" , Mathieu Poirier , Suzuki K Poulose , Mike Leach , Adrian Hunter , Andi Kleen , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v2 5/8] perf auxtrace: Change to use SMP memory barriers Message-ID: References: <20210602103007.184993-1-leo.yan@linaro.org> <20210602103007.184993-6-leo.yan@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210602103007.184993-6-leo.yan@linaro.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 02, 2021 at 06:30:04PM +0800, Leo Yan wrote: > The kernel and the userspace tool can access the AUX ring buffer head > and tail from different CPUs, thus SMP class of barriers are required > on SMP system. > > This patch changes to use SMP barriers to replace mb() and rmb() > barriers. > > Signed-off-by: Leo Yan Acked-by: Peter Zijlstra (Intel)