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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1DCC6C43334 for ; Wed, 20 Jul 2022 00:06:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234741AbiGTAF3 (ORCPT ); Tue, 19 Jul 2022 20:05:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45860 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232782AbiGTAFO (ORCPT ); Tue, 19 Jul 2022 20:05:14 -0400 Received: from sin.source.kernel.org (sin.source.kernel.org [145.40.73.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 662D7D136 for ; Tue, 19 Jul 2022 17:05:13 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id 85098CE1B63 for ; Wed, 20 Jul 2022 00:05:11 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 04B9CC341C6; Wed, 20 Jul 2022 00:05:08 +0000 (UTC) Date: Tue, 19 Jul 2022 20:05:07 -0400 From: Steven Rostedt To: Kent Overstreet Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, pmladek@suse.com, enozhatsky@chromium.org, linux@rasmusvillemoes.dk, willy@infradead.org Subject: Re: [PATCH v4 00/34] Printbufs - new data structure for building strings Message-ID: <20220719200507.361b06ee@rorschach.local.home> In-Reply-To: <7462e934-f746-eef7-ff92-0eeb8cc08b82@gmail.com> References: <20220620004233.3805-1-kent.overstreet@gmail.com> <20220719191522.4002a5fb@gandalf.local.home> <7462e934-f746-eef7-ff92-0eeb8cc08b82@gmail.com> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 19 Jul 2022 19:43:46 -0400 Kent Overstreet wrote: > On 7/19/22 19:15, Steven Rostedt wrote: > > On Sun, 19 Jun 2022 20:41:59 -0400 > > Kent Overstreet wrote: > > > >> Core idea: Wouldn't it be nice if we had a common data structure and calling > >> convention for outputting strings? > > > > Because seq_buf gives us this already, the cover letter really just needs > > to state exactly what the benefit is to replace seq_buf with printbuf (and > > why seq_buf can not be simply extended to do some extra features). > > - seq_buf has the wrong semantics on overflow for what vsnprintf needs. More specific please. > - seq_buf is somewhat unnecessarily coupled to tracing needs - the > readpos member has nothing to do with outputting formatting strings, and > some of the pretty-printers are tracing specific and don't really belong > in a generic pretty-printing library. That's not really a benefit between the two. > > And, when I tried to talk to you about changing seq_buf to be more > suitable you didn't respond - you just dropped off the IRC discussion we > were having. I told you I've been swamped and this wasn't the best time for me. I can't drop everything for you. > > > > > I just applied your series and ran the tracing selftests and several of > > them failed. > > > > # cd tools/testing/selftests/ftrace/ > > # ./ftracetest > > Thank you for telling me where to find the tests. It would've saved us > some back and forth (and I could've gotten on this sooner) if you'd > responded when I asked before. It's in kernel selftests, they are not hard to find. > > It may seem like the perfectly natural place to look to you - who works > on the code - but to someone who works on a variety of subsystems, each > of which puts their test code (if they have any!) in a different place, > it wasn't. All the subsystems tests should be in tools/testing/selftests this isn't just where tracing goes. It's the standard place. > > However, when I enabled all the tracing kernel config options, your > tests are now failing to run at all with: > > db_root: cannot open: /etc/target > > So now I've got to debug your tests, too. Gah. WTF? -- Steve