From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A18E0CDB475 for ; Mon, 22 Jun 2026 08:34:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=y2+mOP/j6lYd9qVyAamBJsy1djQW4CKGJJUDwRnuyXs=; b=QnQuVojKgeeTSPDzigVq0+EXak r2b3KtAxFJEGoXutP2ONIrjC7hhr3v6L8JT++5cB87stWCnEDDf2LfXd+peA18eo+CdqW3GmnZrbv RSadZpzdD3uizYlWnmELYN9txKKZbOMtPoPSBp2LQRNAbN1xS/06AIKa1EAlo2EbeuRzJmw+996oa 51rsQnpcRD+QmTunNNFQpZdlDSBir+XDiM9r01fgkwJGpy3Ew71JyxrRo3ryA8bni/KC0UIbhesYv cUCSLluGAK5P6Kvofa2WaAjIS7I7g10YlFFU+7e6VdFQyBbjfjlu6sTmWlbG2HEgg0BuO0LXvCTyK eeQFjc8A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wba7B-00000004g3N-3vsQ; Mon, 22 Jun 2026 08:34:45 +0000 Received: from casper.infradead.org ([2001:8b0:10b:1236::1]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wba7A-00000004g2v-0Fua for linux-arm-kernel@bombadil.infradead.org; Mon, 22 Jun 2026 08:34:44 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=y2+mOP/j6lYd9qVyAamBJsy1djQW4CKGJJUDwRnuyXs=; b=TuPlTRCUatJuuJgUUAwvzHwMKv dWwVfsTqUjTJh9SX5fPBCQGdiQcrZu7Ws4gSZKgN7rA0kNKxui7b5LEtKWEEQDe4V7j5A8N0jYuRY uas/iKoJjFjR3gKpo0uOWWxjsbSNbU4N4b8MGJpMvU190ZELYDlzfAoftHa96t+aSCVqbpoMUbpfL uOWtb+WeGCTtTYOdcuf3kQ/LcfWhZsQK+C/ri3C/zOHCtiyE1n8uDvDi3TDA+Xy225DqvitJuIeN0 RneapmfngTU0PhOUCG9gkRpGwiGc3BAbq6jkG1ZvAJCnP1chuakPaLn4PyoFg+CyhHRv/kOJ0Ywl3 cXoCNRYg==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.99.1 #2 (Red Hat Linux)) id 1wba77-00000003u7U-1iUV; Mon, 22 Jun 2026 08:34:42 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 52395300B5F; Mon, 22 Jun 2026 10:34:40 +0200 (CEST) Date: Mon, 22 Jun 2026 10:34:40 +0200 From: Peter Zijlstra To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , Linus Torvalds , Sebastian Andrzej Siewior , John Ogness , Thomas Gleixner , Julia Lawall , Yury Norov , linux-doc@vger.kernel.org, linux-kbuild@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, dri-devel@lists.freedesktop.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-rdma@vger.kernel.org, linux-usb@vger.kernel.org, linux-ext4@vger.kernel.org, linux-nfs@vger.kernel.org, kvm@vger.kernel.org, intel-gfx@lists.freedesktop.org Subject: Re: [PATCH 0/2] tracing: Move trace_printk.h out of kernel.h Message-ID: <20260622083440.GX49951@noisy.programming.kicks-ass.net> References: <20260621093430.264983361@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260621093430.264983361@kernel.org> X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Sun, Jun 21, 2026 at 05:34:30AM -0400, Steven Rostedt wrote: > There's been complaints about trace_printk() being defined in kernel.h as it > can increase the compilation time. As it is only used by some developers for > debugging purposes, it should not be in kernel.h causing lots of wasted CPU > cycles for those that do not ever care about it. > > Instead, add a CONFIG_TRACE_PRINTK_DEBUGGING option that developers that do > use it can set and not have to always remember to add #include > to the files they add trace_printk() while debugging. It also means that > those that do not have that config set will not have to worry about wasted > CPU cycles as it is only include in the CFLAGS when the option is set, and > its completely ignored otherwise. Did you forget your C 101 class? If you use a function, you gotta include the relevant header. You don't see userspace saying: 'Hey, you know what, perhaps we should add stdio.h to every other header, just in case someone wants to printf()' either. I really don't understand your argument. Yes, maybe someone will forget and then either their editor (if they have a halfway modern setup with LSP enabled) or their build will complain, but so what? This is all trivial stuff, surely we have more pressing matters to concern outselves with?