From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) (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 EF1BB18FDDB; Sun, 19 Oct 2025 17:46:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.16 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760896019; cv=none; b=AlK6LnFGx0yxhdyoJ6PTboWM/P3vvo7b8wPUdl3aAYjy2zUHPiQtSLwXDkSu9gBODe874Q5v5N8urvWQm6FLFnOvBq7ECt4LzxFYsRmLPTjClnVD2jbVyU7poYnbhHG7qL1+KtM1N8TsjOEt6BPLR8mlfYL0jfkV8znAszxvch4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760896019; c=relaxed/simple; bh=iBrjG+mJpNWJvcAM9eoZJjaPCJi7C0ctS5AIbIXK6QE=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=YBrN/AQcm7d+eZxvzATvDs+VtT2zBlJbWRE2/uYuX4zXd9xoXv1XPKORVzB6Hs0kFawh/j9qGFrQVgUgrCQJDSg4TkogVmfn/Kjlszj9gZiumj5kpfnvxBKAD1HQYXJ4BjA/bJVt6bgQA7e4fHRomIsK22uqHD8lib0i5bfAGUM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org; spf=pass smtp.mailfrom=goodmis.org; arc=none smtp.client-ip=216.40.44.16 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (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 (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 6946613B6F8; Sun, 19 Oct 2025 17:46:49 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf05.hostedemail.com (Postfix) with ESMTPA id D81F520015; Sun, 19 Oct 2025 17:46:47 +0000 (UTC) Date: Sun, 19 Oct 2025 13:46:46 -0400 From: Steven Rostedt To: "Masami Hiramatsu (Google)" Cc: Mark Rutland , Mathieu Desnoyers , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: Re: [PATCH v3 1/2] tracing: Allow tracer to add more than 32 options Message-ID: <20251019134646.6d6f683d@batman.local.home> In-Reply-To: <20251018000130.aa69bd5b6670715b1c52d387@kernel.org> References: <175918528341.65920.10238038992631012350.stgit@devnote2> <175918529300.65920.15856373929947126262.stgit@devnote2> <20251015172020.5966beaf@gandalf.local.home> <20251018000130.aa69bd5b6670715b1c52d387@kernel.org> X-Mailer: Claws Mail 3.17.8 (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: 4nky5dtycpti38in66aecbg6ctrdkbkt X-Rspamd-Server: rspamout08 X-Rspamd-Queue-Id: D81F520015 X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX1/xTXzLG1bigaj/8ief4UXLMYw1TgiDtqI= X-HE-Tag: 1760896007-974800 X-HE-Meta: U2FsdGVkX18Rq9DtklkLlXJJaE4ju4AQ85IvNzblxh6lj6yjIHV3wnzXOqzqcvF0TfoCRckQsZcHtI9X1gSvoox0gwSxGPWFk+bcK92ZahMOcCrS9JHkcYQGLyMAJvaBnms1Clc66K5hK/I+BliUIHzKD4ZRKKQ6mg+FfoJCOo0VCjPRPr/7PJbOWpsHkcpiJ7EcTeF6MRVMDsF3ektyZDP+ltbbj3HOvMQ2STsUWzaDNfAqnRQ9vZAXe34Jgyfn5HCgUvb8XGgbJ1ONRBTzOllQdJNkfhyUhxSF5ZjhugL7xvCr2MEJZS9xN7IkHy/wYFsI4ldAnSh7zldxe0kp1eZBQ+IihPnrxvTp6YUu+Oqd2/NTjzUMJ3lA2PTkdsPOmjR+GRrMYZgT6Ac7r7gmwA== On Sat, 18 Oct 2025 00:01:30 +0900 Masami Hiramatsu (Google) wrote: > On Wed, 15 Oct 2025 17:20:20 -0400 > Steven Rostedt wrote: > > I could not find any other enum64 usage, so I doubt it is > available. (Does it depend on compiler?) > It seems C23 standard support it... Bah, I thought I saw it used, but it appears it's BPF that does something special. > > > > > Not to mention, using const u64 requires saving these numbers in an address > > and referencing them, instead of doing it inlined in text. That is, using > > u64 instead of enum64 is both slower and wastes more memory. > > Yeah, I expected that the compiler could easily optimize correctly, but > maybe not? I doubt it. The values are exported to be allowed to be used in other files, so I doubt it can optimize it. The only thing I can think of is to unravel the enum into a bunch of #defines, that have the bit shifts. -- Steve