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Sun, 05 Jul 2026 23:32:36 -0700 (PDT) From: Li Pengfei X-Google-Original-From: Li Pengfei To: rostedt@goodmis.org, mhiramat@kernel.org Cc: mathieu.desnoyers@efficios.com, mark.rutland@arm.com, linux-trace-kernel@vger.kernel.org, linux-kernel@vger.kernel.org, zhangbo56@xiaomi.com, lipengfei28@xiaomi.com Subject: Re: [RFC PATCH v4 0/3] trace: stack trace deduplication for ftrace ring buffer Date: Mon, 6 Jul 2026 14:31:54 +0800 Message-Id: <20260706063154.1947674-1-lipengfei28@xiaomi.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260616064119.438063-1-lipengfei28@xiaomi.com> References: <20260616064119.438063-1-lipengfei28@xiaomi.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=UTF-8 Content-Transfer-Encoding: 8bit From: Pengfei Li Hi Steven, Masami, Gentle ping on this v4 series now that the 7.2 merge window has settled. I'd especially value a quick steer on the two design questions from the cover letter, since they shape how I respin: 1. Eager vs lazy allocation of the element pool (~8 MB at the default bits=14 when CONFIG_FTRACE_STACKMAP=y, whether or not userspace ever enables the option). Is eager allocation acceptable, or should v5 switch to lazy allocation on the first 'echo 1 > options/stackmap'? 2. Whether to introduce the stack_map_bin binary interface now, or ship the text stack_map interface first and add the binary export once trace-cmd / libtraceevent integration is designed. Happy to respin in either direction. Full series for reference: https://lore.kernel.org/all/20260616064119.438063-1-lipengfei28@xiaomi.com/ Thanks, Pengfei