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[34.140.115.198]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-439f82078a1sm9543853f8f.29.2026.03.11.08.23.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 11 Mar 2026 08:23:29 -0700 (PDT) Date: Wed, 11 Mar 2026 15:23:26 +0000 From: Vincent Donnefort To: Markus Elfring Cc: linux-trace-kernel@vger.kernel.org, kernel-team@android.com, kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, Joey Gouly , Marc Zyngier , Masami Hiramatsu , Mathieu Desnoyers , Oliver Upton , Steven Rostedt , Suzuki Poulouse , Zenghui Yu , LKML , "Aneesh Kumar K.V" , John Stultz , Quentin Perret , Will Deacon Subject: Re: [PATCH v13 03/32] ring-buffer: Introduce ring-buffer remotes Message-ID: References: <20260306143536.339777-4-vdonnefort@google.com> <677c7ad6-6e67-4011-b2d0-03d0d58547ce@web.de> Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <677c7ad6-6e67-4011-b2d0-03d0d58547ce@web.de> On Fri, Mar 06, 2026 at 05:37:35PM +0100, Markus Elfring wrote: > … > > It is expected from the remote to keep the meta-page updated. > > See also once more: > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/submitting-patches.rst?h=v7.0-rc2#n94 > > > … > > +++ b/kernel/trace/ring_buffer.c > … > > +int ring_buffer_poll_remote(struct trace_buffer *buffer, int cpu) > > +{ > … > > + cpus_read_lock(); > > + > > + /* > > + * Make sure all the ring buffers are up to date before we start reading > > + * them. > > + */ > > + for_each_buffer_cpu(buffer, cpu) { > … > > + } > > + > > + cpus_read_unlock(); > > + > > + return 0; > > +} > … > > How do you think about to use another lock guard here? > https://elixir.bootlin.com/linux/v7.0-rc1/source/include/linux/cpuhplock.h#L48 Sorry, I forgot to reply to you. I had to respin a new version so I have made the changes you've suggested. Thanks, Vincent > > Regards, > Markus