From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 028401DD525 for ; Fri, 19 Jun 2026 15:40:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781883633; cv=none; b=cpxW7updVXpdxNfiQmLVTfeCfvYHrphC5yw8+1kxaPQAg1xw5FxC83Gxg1rOVK592cAmWxuiBMsmQo5assFwvjXQHumMfBO20cdhvMYTFYcL6RwR4Zz0hno6yICXceUW+a2dM1jnuoIXOXm8pkq+/eCvzpIbX5rWQAkTKvOQc+s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781883633; c=relaxed/simple; bh=e6eoKnaGRvilaknGcYjuOl+Oh2E3ApuLsu1O9j7wWSQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=nWIiivCOrhlpO/RlwJxCOCkKKmobSbToyWJt71kk4eT6aCncgpfr7u/iPcTGlBjFAoNHIdUtTGEdvK9Vj0VwYADJFMJyIVxAXyuqI+zmBwR8sWLc+/MnR7X6UaOUb2ciSfTHLtQvisUhaMK+WuQe+3hxi3rSrGytlDy/DH9B6Nk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=il9pLWyB; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=3dTRKg3i; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="il9pLWyB"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="3dTRKg3i" Date: Fri, 19 Jun 2026 17:40:25 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1781883627; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=crCF1ncANDpdaz0f9ddKny/jojJlgqYkbupptryBmdc=; b=il9pLWyB6g7WPQbZXbhit/Qqbc1uesiYGsOxg9x7aF76VubewXJBDd/xc3VuPpa3B/1c3W +RRMAu8GSveraOHuYX1g2L/qfot302Qox1jMx/Gzx9obJB2i6tjSTTH0IWpnT+/bpDYhOP WMsxfTuvjsIoMfIlLbNHGCoYDtBboF+s3uxthhsIXSCVEwxjOYzoISxa6Hn5/aRXSBetFC 9fCXUwnm+dz2NAtsp6rHW0A3jZkSEoMoJZyCuc3MIKy10vaO32xQ7L3yteV0q92bHeX+30 8+p/drXOVnO/+Fsl8ActQsnsu27ANfEXbHW47TtpPds8AZsMC49YAgmr0TIE4w== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1781883627; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=crCF1ncANDpdaz0f9ddKny/jojJlgqYkbupptryBmdc=; b=3dTRKg3i6cXfRq5qlGdObKMUZZR5FjgdJhxs+lEzGiJkYWoXr4wKI24MEmgFzBAO84QW4q Vjv2G4iW12CKCiBw== From: Sebastian Andrzej Siewior To: Linus Torvalds , John Ogness , Thomas Gleixner , Peter Zijlstra Cc: Steven Rostedt , Yury Norov , LKML , Masami Hiramatsu , Mathieu Desnoyers , Ao Sun , David Carlier , Karl Mehltretter , Martin Kaiser , Pengpeng Hou , Qian-Yu Lin , Rik van Riel , Rosen Penev , Shuvam Pandey , Vineeth Pillai , Yash Suthar , Yu Peng Subject: Re: [GIT PULL] tracing: Updates for 7.2 Message-ID: <20260619154025.h4BHc5wi@linutronix.de> References: <20260616180122.57a3b426@fedora> <20260619081513.3e4a1fb0@fedora> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On 2026-06-19 07:35:15 [-0700], Linus Torvalds wrote: > On Fri, 19 Jun 2026 at 05:15, Steven Rostedt wrote: > > > > Many developers use trace_printk() over printk(). > > You're on some bad drugs, Steven. > > By "many developers" you clearly must have meant "almost nobody". I do use it for debugging all the time. The alternative is printk but it is "slower" if it throws everything to the UART which I prefer to limit to BUG/WARN kind of messages. Also it does not record the context where this comes from which is often helpful. Afaik it is the only to debug printk. > > Requiring people to add that include for every use case would > > severely limit debugging of the kernel. Would you be OK if we did > > the same for printk? > > Stop making inane and silly arguments that have nothing to do with > reality. > > The two are not the same: > > $ git grep -wl printk | wc -l 3212 $ git grep -wl trace_printk | wc > -l 50 > > and making them sound remotely similar is just making you look dishonst. > > Look, the attached patch makes my defconfig build cleanly, and makes a > > $ touch include/linux/trace_printk.h > > cause my recompile to build just a handful of files. While touching > linux/kernel.h causes thousands of files to be re-build. > > That's a whopping > > 6 files changed, 6 insertions(+), 1 deletion(-) > > to make my tree build without including everywhere. > > Now, that's _just_ my defconfig, and the full build clearly has a > handful of other cases. From a quick look, mostly in the 'samples' > directory. > > But it looks like a *handful* of other cases. > > Now, if the same was true for printk(), I'd happily split that into > some other header too. > > But it isn't. > > Because we live in reality. > > Linus Sebastian