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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id B6913C43334 for ; Wed, 20 Jul 2022 00:05:12 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 2D8816B0072; Tue, 19 Jul 2022 20:05:12 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 286E86B0073; Tue, 19 Jul 2022 20:05:12 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 150626B0074; Tue, 19 Jul 2022 20:05:12 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id F33786B0072 for ; Tue, 19 Jul 2022 20:05:11 -0400 (EDT) Received: from smtpin08.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id B8DC71A040A for ; Wed, 20 Jul 2022 00:05:11 +0000 (UTC) X-FDA: 79705533222.08.95C6FC9 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf19.hostedemail.com (Postfix) with ESMTP id 5B8D51A008E for ; Wed, 20 Jul 2022 00:05:11 +0000 (UTC) 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 dfw.source.kernel.org (Postfix) with ESMTPS id 8486961598; Wed, 20 Jul 2022 00:05:10 +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 ARC-Authentication-Results: i=1; imf19.hostedemail.com; dkim=none; dmarc=none; spf=pass (imf19.hostedemail.com: domain of "SRS0=7KbO=XZ=goodmis.org=rostedt@kernel.org" designates 139.178.84.217 as permitted sender) smtp.mailfrom="SRS0=7KbO=XZ=goodmis.org=rostedt@kernel.org" ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1658275511; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=6q9Ga+dDF5XEws1GdP0tYDqCTuSmcISvajW2TUKjhs4=; b=1d/WtecoR+nHit4xvyv0G+7b/CKwV6R4H+eepoYBaoDf8Ko/1UtIpOFuiOebwRu0VOj1Fo qzlNSWZfzCxwBDUkF8+Q/kvv4mOFtAliprkRibXBLAQWo/00ihp/mOMXxEPbWzIE/KTiJl 4dFq6lSZfWnV2nhLQZN05i1M7bUZjcY= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1658275511; a=rsa-sha256; cv=none; b=oMJwZ6soZVT83ly5PpfmGLcD6/8Bbx+TES8so00fpqDolnX0qGs7N2uKnEQ7L0ux/yUjsI t4AGPezCcic7RcrBa6NQbHttT7y31l29HI2N9EG22BqVVGtHV2gxbCWxpBnXTvOybb0JyJ Jiz78w1xgMXnXSYqG2pOe6LSfQCQxJg= X-Rspamd-Queue-Id: 5B8D51A008E Authentication-Results: imf19.hostedemail.com; dkim=none; dmarc=none; spf=pass (imf19.hostedemail.com: domain of "SRS0=7KbO=XZ=goodmis.org=rostedt@kernel.org" designates 139.178.84.217 as permitted sender) smtp.mailfrom="SRS0=7KbO=XZ=goodmis.org=rostedt@kernel.org" X-Rspam-User: X-Rspamd-Server: rspam04 X-Stat-Signature: xe4kzhfc6djdumqxmj4dboir8i8bfeew X-HE-Tag: 1658275511-176457 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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