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[34.140.204.24]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-442cd333326sm29694785e9.16.2025.05.08.02.14.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 08 May 2025 02:14:22 -0700 (PDT) Date: Thu, 8 May 2025 10:14:18 +0100 From: Vincent Donnefort To: Steven Rostedt Cc: mhiramat@kernel.org, mathieu.desnoyers@efficios.com, linux-trace-kernel@vger.kernel.org, maz@kernel.org, oliver.upton@linux.dev, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, jstultz@google.com, qperret@google.com, will@kernel.org, kernel-team@android.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 02/24] tracing: Introduce trace remotes Message-ID: References: <20250506164820.515876-1-vdonnefort@google.com> <20250506164820.515876-3-vdonnefort@google.com> <20250507202444.43963c84@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250507202444.43963c84@gandalf.local.home> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250508_021424_146055_CDDABBBE X-CRM114-Status: GOOD ( 12.11 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org [...] > > + remote->cbs->unload_trace_buffer(remote->trace_buffer_desc, remote->priv); > > + return -ENOMEM; > > + } > > + > > + return 0; > > +} > > + > > +static void trace_remote_unload(struct trace_remote *remote) > > +{ > > + lockdep_assert_held(&remote->lock); > > + > > + if (!trace_remote_loaded(remote) || trace_remote_busy(remote)) > > + return; > > Can this cause leaks? Should trace_remote_unload() return an error value to > let the caller know it wasn't unloaded? No risk of leak here. This acts a like a refcount to make sure the buffer is unloaded only when no one is reading and tracing_on=0. [...]