From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) (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 845ED2475CB; Wed, 15 Oct 2025 21:20:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.12 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760563224; cv=none; b=WiLayn16M6kCZX2bqYq9Ms+fWhv2HStqDS/gRHOgqTMnLVifqHqps6c/Vk43JegdEAlKHbDvbmBA+P4kQhzB2NspytotndRFHEvgcgEgHPLppMEkoyXQ8OK9JJserMItKPMz9/i6N3NpDS2qcBceWg2WzrUP4mL1sVJcU5/sp4U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760563224; c=relaxed/simple; bh=EOxifxp6BWGJCSPE+t53wdqzeFijrm/u/4LqfvO1BIc=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=Qqz3AE8HQIYUkff+pvYi8RO6cQ03Ny/w7VZfRHyJbKUT481cPnfNyP6bQseZiED7cLgcmhAHKu0g6Ld9LBpEBA4zapkgkolhdyNWEkvIhVa7xdhw2F5Qi2UoiVD0CVn/Qh1l5/kuy7gl/Fc3PxTExgoNo3x4CESj6F3qz548XBI= 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=216.40.44.12 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 omf16.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id C6D7CB953A; Wed, 15 Oct 2025 21:20:13 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf16.hostedemail.com (Postfix) with ESMTPA id F34E02000E; Wed, 15 Oct 2025 21:20:11 +0000 (UTC) Date: Wed, 15 Oct 2025 17:20:20 -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: <20251015172020.5966beaf@gandalf.local.home> In-Reply-To: <175918529300.65920.15856373929947126262.stgit@devnote2> References: <175918528341.65920.10238038992631012350.stgit@devnote2> <175918529300.65920.15856373929947126262.stgit@devnote2> 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: oj795q6u9q9iu85od7rb7oc8eszdpre1 X-Rspamd-Server: rspamout05 X-Rspamd-Queue-Id: F34E02000E X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX19FhodM+VZGak7x5DFU+TTZTy9PHWLL5AE= X-HE-Tag: 1760563211-601402 X-HE-Meta: U2FsdGVkX19lh7rtuHgALC7BeoYzF4V+Nz1FFo8Nz7c9cuEnyAwiTw9GA4JBwe/+LLvNKlzehfDn/q9I8Ads+fgCFw2qXJWOkRX0qLwyPPOJnYq6INo6ENYYm/idTe9xnBOc4+bxlKZua3OgdpWa+h7KZ/v5ZjjY6nQU8rPUxUfq6lb2XOu3KgT/+LzNg+oKJr+gsWj+wiYm9S8+7JJAsauPjub/p/BsnmVSqH3crR6Dewl7bWqrKz2Z9i/Q7IOXeOPvwVujbkFQ/ixXLMx7irbtbWvcFJwLgO3m+nuTPqbSZiAaDqpnrHa//w06vRToHu7BvS0Lbq/BaXI/rpWJB9d51XT6tH3W On Tue, 30 Sep 2025 07:34:53 +0900 "Masami Hiramatsu (Google)" wrote: > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -86,6 +86,11 @@ void __init disable_tracing_selftest(const char *reason) > #define tracing_selftest_disabled 0 > #endif > > +/* Define TRACE_ITER_* flags. */ > +#undef C > +#define C(a, b) const u64 TRACE_ITER_##a = (1ULL << TRACE_ITER_##a##_BIT); > +TRACE_FLAGS > + > #undef C > -#define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT) > +#define C(a, b) extern const u64 TRACE_ITER_##a; > > -enum trace_iterator_flags { TRACE_FLAGS }; > +TRACE_FLAGS > +#undef C Why all this work when this could have been simply fixed with a: -enum trace_iterator_flags { TRACE_FLAGS }; +enum64 trace_iterator_flags { TRACE_FLAGS }; ? 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. -- Steve