From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) (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 924103376B8; Tue, 18 Nov 2025 13:57:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.10 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763474234; cv=none; b=QMkWv9ZKFJS0g2GhEMlJJBlWM5ZnjV30YRj/VNEScSsVTThUXHmOMXIDgTtEMO5viO2IE/IH8x7lTw7FVDh8/Maezc2iqaaGf9hQk3PFyxvEk8J9UQRurbxLDLb4k3pwkmPnl4uSy/t1muCC+yJYpJ2miV901/a2kBpRX7jLMZU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763474234; c=relaxed/simple; bh=C0vpxMUpcMm1Jtr1s/Hwfu0NydpQe3jkyLTCqmymRAo=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=gkvV71IaTy1+INA1DqjtiWHeV8mCu1BGslv4D7fJBmnpz1gVvyjbZdgZkczhLT6x7yejdVZ25PcPQg5X58HWs0G6OovdTexpD53UreajEFups1cFErk0N3V8im0Lv1bxpSKJ5Qy8bctom6jiBuwiX7H8ZuPtlL0DnrkRXHIb6Mo= 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=216.40.44.10 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 omf16.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 6F3FA14053C; Tue, 18 Nov 2025 13:57:09 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf16.hostedemail.com (Postfix) with ESMTPA id 989E82000D; Tue, 18 Nov 2025 13:57:06 +0000 (UTC) Date: Tue, 18 Nov 2025 08:57:33 -0500 From: Steven Rostedt To: "Masami Hiramatsu (Google)" Cc: Steven Rostedt , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Mark Rutland , Mathieu Desnoyers , Andrew Morton , Peter Zijlstra , Thomas Gleixner , Ian Rogers , Namhyung Kim , Arnaldo Carvalho de Melo , Jiri Olsa , Douglas Raillard Subject: Re: [POC][RFC][PATCH 0/3] tracing: Add perf events to trace buffer Message-ID: <20251118085733.2a9ce5b0@gandalf.local.home> In-Reply-To: <20251118085324.32816807@gandalf.local.home> References: <20251118002950.680329246@kernel.org> <20251118120821.0c47ef684b53d5d9a2d6dc83@kernel.org> <20251117224227.782f6eab@batman.local.home> <20251118171147.72d4f1e26407f8d54720e0f2@kernel.org> <20251118085324.32816807@gandalf.local.home> 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: 7sfjujzhwn93opepwbtjftxyr844ueff X-Rspamd-Server: rspamout07 X-Rspamd-Queue-Id: 989E82000D X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX18wmqGD2xByqUytnGOmmm5fZa8Y4nNbztI= X-HE-Tag: 1763474226-370225 X-HE-Meta: U2FsdGVkX1/2PM3H1K5tv4igudRZVMWL1DnIX/s1lnigA6Ew6EbKafz6jObHdx7uYyuaSh8FeDAC4anWT7F56Fn4M1FgX8AOOntgDOM9Oph14TGUh4ERd+Dc533LENAHcKh4j4elt4DFGC/wh9QbINyCBAdoaV0v/uF1vGyjhpeV2Ys21kxkcolaYNaOB+kZifL7KLVU5PxK+Ez7/bh1rYn2qdWOIwc0SSlJ/c1U4MNYXRXERNb8puSvTORi4wP7yPHH6i9Wy36oDOLwISDMUQzZvwgYl4WAFkZeDS5eQjBhwQhZI+kKz8vhKYWdA/akC36b19Yk22dxquT7oaXdAFrODagYQEgQm5JTVNsiy5lTvje3n95fguzLdTQ4pfjG On Tue, 18 Nov 2025 08:53:24 -0500 Steven Rostedt wrote: > > Yes, so if user adds more than that, it will return -ENOSPC. > > The issue is that the ids are defined by what is possible, not by what the > user enables. Now we could take 4 more bits from the mask and bring the raw value down to just 52 bits. 2^51 at 4GHz is still 6 days. Which is plenty more than required. This will make the id 12 bits, or 4096 different defined events. -- Steve