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[195.250.132.146]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-48af502cf08sm5343668f8f.9.2026.09.29.08.10.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 29 Sep 2026 08:10:00 -0700 (PDT) Date: Tue, 29 Sep 2026 17:09:58 +0200 From: Petr Mladek To: Wang Wensheng Cc: rostedt@goodmis.org, john.ogness@linutronix.de, senozhatsky@chromium.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] printk_ringbuffer: Avoid needless read of prb_desc Message-ID: References: <20260926094502.251204-1-wsw9603@163.com> Precedence: bulk X-Mailing-List: linux-kernel@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: <20260926094502.251204-1-wsw9603@163.com> On Sat 2026-09-26 17:45:02, Wang Wensheng wrote: > Since commit f244b4dc53e5 ("printk: ringbuffer: Improve prb_next_seq() > performance"), desc_read() allows @desc_out to be NULL. We can drop the > local `desc` variable in desc_reopen_last() and prb_first_seq(). Also > update the comment for desc_read(). > > v1->v2: > Update the comment suggested by John. > > Signed-off-by: Wang Wensheng > Reviewed-by: Petr Mladek > Reviewed-by: John Ogness JFYI, the patch has been comitted into printk/linux.git, branch for-7.4. Best Regards, Petr