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[209.85.208.48]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-ae6e7e910d2sm872079566b.2.2025.07.14.13.00.44 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 14 Jul 2025 13:00:44 -0700 (PDT) Received: by mail-ed1-f48.google.com with SMTP id 4fb4d7f45d1cf-60c93c23b08so9304175a12.3 for ; Mon, 14 Jul 2025 13:00:44 -0700 (PDT) X-Forwarded-Encrypted: i=1; AJvYcCWSBMtque/44VP2rd3Bi7yCZR39rVXcrogVvhFOGhXyJM3j43VTC7syV47R6ncVTyJlGpoujy39caruMfs=@vger.kernel.org X-Received: by 2002:a05:6402:2109:b0:60f:be9b:a2cc with SMTP id 4fb4d7f45d1cf-611e765076emr11335991a12.9.1752523243917; Mon, 14 Jul 2025 13:00:43 -0700 (PDT) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: In-Reply-To: From: Linus Torvalds Date: Mon, 14 Jul 2025 13:00:27 -0700 X-Gmail-Original-Message-ID: X-Gm-Features: Ac12FXxEwj76rBnjNiSKWrG4545ZDG92vEKpvEMqe2y_grVL7YGP-d-bLGOQCcM Message-ID: Subject: Re: [RFC] LTTng upstreaming next steps To: Mathieu Desnoyers Cc: Steven Rostedt , Greg Kroah-Hartman , Christoph Hellwig , "Masami Hiramatsu (Google)" , Peter Zijlstra , Ingo Molnar , Thomas Gleixner , linux-kernel Content-Type: text/plain; charset="UTF-8" On Mon, 14 Jul 2025 at 12:41, Mathieu Desnoyers wrote> > A) Bulk upstreaming Honestly, I don't see the point. The reason the current tracting infrastructure got merged was that people were willing to do it incrementally. I was hoping that there would be some kind of eventual merging of the different ring buffers etc. That was discussed as a hopeful end goal originally, but here were are, decades later, and it never happened. And honestly, I am NOT interested in just having two different tracing models. If people need two tracing models, then the other one will be out of tree. It's that simple. Because if people haven't been able to agree on common models in the decades past, I really don't see the point in maintaining two models indefinitely side-by-side in the upstream kernel. So as far as I'm concerned, this discussion is not a discussion. Either there's a way to merge things incrementally with SHARED infrastructure, or there isn't. No "two different and disjoint trace buffers". No "two different and disjoint trace interfaces". And very clearly - based on history - that unification will never happen. Linus