From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 315073612ED; Tue, 7 Jul 2026 16:00:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.15 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783440049; cv=none; b=C8U0v/aEj74OrbaTXpSovIIdDlKveKMILOQkaRR+d95P41Q9vuFkSPbdymzKvhogHdRDdYU5laB2cXTnl2KOM53Yu+AIGtVLZs1r32mngFuw1Z3PSoDnIGJUAUduI+VkIqG3PmmatnOfWbduiuyAez1cBy0QcN8q98QfleNSwmI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783440049; c=relaxed/simple; bh=1iLInY17sRnF1Bnlfy+Ib9X5BvBkkmir9bArxM2d1H4=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=d/d83HYeP0c4GF0/j+65tQUzXggxl8oUIlvYs5gVYi3sTrJGrizviHfnJCl/5JsgJRPmHVPaGyrE2IR0FNzLaLV41xyH5j8UlgCSaAwf9enB+MAoNgWvTswt7qf3cX8mtrTJk8CnrbPj2hXlqm7xqQcx3J9scKmkkJVfzjnTjZA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=goodmis.org; spf=pass smtp.mailfrom=goodmis.org; arc=none smtp.client-ip=216.40.44.15 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=goodmis.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=goodmis.org Received: from omf05.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 1752D1C3A94; Tue, 7 Jul 2026 16:00:46 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf05.hostedemail.com (Postfix) with ESMTPA id 6EAAF2000E; Tue, 7 Jul 2026 16:00:43 +0000 (UTC) Date: Tue, 7 Jul 2026 12:00:46 -0400 From: Steven Rostedt To: Mykyta Yatsenko Cc: bpf@vger.kernel.org, ast@kernel.org, andrii@kernel.org, daniel@iogearbox.net, kafai@meta.com, kernel-team@meta.com, eddyz87@gmail.com, memxor@gmail.com, Mykyta Yatsenko , linux-trace-kernel@vger.kernel.org Subject: Re: [PATCH bpf-next v2 0/3] tracing: Expose tracepoint BTF ids via tracefs Message-ID: <20260707120046.31573548@gandalf.local.home> In-Reply-To: <20260518-generic_tracepoint-v2-0-b755a5cf67bb@meta.com> References: <20260518-generic_tracepoint-v2-0-b755a5cf67bb@meta.com> X-Mailer: Claws Mail 3.20.0git84 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Stat-Signature: k87xr15tbwbuz4jtafu5ec3kdmfycrte X-Rspamd-Server: rspamout02 X-Rspamd-Queue-Id: 6EAAF2000E X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX18TssPEFq94GGqlz+p+9aRp8eeLIFlutH4= X-HE-Tag: 1783440043-387885 X-HE-Meta: U2FsdGVkX1/Tx9nyManP9zwP+a3L82cJx81X4QDK9XWbb3e8XlhJm0qXPF1os5W79zy/LIkiAsEW8f27ieUKfLPdreBktAOtFsAg8ZPCAjErgfds4BgoppbOxbCr0+CxP3uiRUALSGhPR0xu72VIJiVuj07x7zpA3cFJ+t5VPzl9MG8PDXKAG+7ykiZu6A9DFgrHhwOFZacggrxph8MUe/IVa5QZHyhXD2TLA7aJgnrH9b6g9jiXy+0FRQHNksiQJl9ISNHjYBLuGtGBk8Cm74mhIeSvEEjG/esQkrh4rep5iAUnASGcIKnlmmDc87IKPa9PxRI0DrGF1/2t/AM5wkyLPPGYTDQ7 On Mon, 18 May 2026 08:23:14 -0700 Mykyta Yatsenko wrote: > BPF and other consumers that want to attach to or decode a generic > tracepoint need three pieces of BTF information for it: > > - the BTF of the object that owns the tracepoint's types > - the FUNC_PROTO describing the tracepoint arguments (with names), > consumed by raw_tp / tp_btf BPF programs > - the STRUCT id of trace_event_raw_, the ring-buffer record > consumed by classic BPF_PROG_TYPE_TRACEPOINT programs > > Today none of this is easily discoverable from userspace. The kernel > knows the ids - resolve_btfids fills them in at link time - but > consumers have to search them by the naming convention > ("__bpf_trace_", "trace_event_raw_"), walking BTF for > every tracepoint. I'll pull this in even though it adds 100K to the kernel: text data bss dec hex filename 40506047 15709518 16661184 72876749 45802cd /tmp/vmlinux.new 40499064 15615294 16661184 72775542 4567776 /tmp/vmlinux.old -- Steve