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List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird To: Vincent Donnefort , 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 Cc: LKML , "Aneesh Kumar K.V" , John Stultz , Quentin Perret , Will Deacon References: <20260306143536.339777-4-vdonnefort@google.com> Subject: Re: [PATCH v13 03/32] ring-buffer: Introduce ring-buffer remotes Content-Language: en-GB, de-DE From: Markus Elfring In-Reply-To: <20260306143536.339777-4-vdonnefort@google.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:/7M96EMDdymY+btShE19XvuqDjcyQNoA88jOa7lXVK9lidCIu9B 19mAqvnB/VTl3sYqz8/10ku0BD6XiZD3H6O2tHNK2GOIk/hDfrOjfS7GmXU69FMGL8Rr0oi UzoMwPc095HwOs2OphD7g7r1mQNLXv/sOjaDiZZHtgYyXepez8oBU28OxnEikvG7l35P6Yi 3oHtX+2xWUFPDZ3JfT1wQ== 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See also once more: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Do= cumentation/process/submitting-patches.rst?h=3Dv7.0-rc2#n94 =E2=80=A6 > +++ b/kernel/trace/ring_buffer.c =E2=80=A6 > +int ring_buffer_poll_remote(struct trace_buffer *buffer, int cpu) > +{ =E2=80=A6 > + cpus_read_lock(); > + > + /* > + * Make sure all the ring buffers are up to date before we start readi= ng > + * them. > + */ > + for_each_buffer_cpu(buffer, cpu) { =E2=80=A6 > + } > + > + cpus_read_unlock(); > + > + return 0; > +} =E2=80=A6 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 Regards, Markus