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 X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8400EC43441 for ; Tue, 13 Nov 2018 01:54:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 478EF22507 for ; Tue, 13 Nov 2018 01:54:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=thunk.org header.i=@thunk.org header.b="kL6yimb5" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 478EF22507 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=mit.edu Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730461AbeKMLuM (ORCPT ); Tue, 13 Nov 2018 06:50:12 -0500 Received: from imap.thunk.org ([74.207.234.97]:48572 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725991AbeKMLuM (ORCPT ); Tue, 13 Nov 2018 06:50:12 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=thunk.org; s=ef5046eb; 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:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=XIn5Dgny0xYzOOoOoJt1WdTT0OEV52cEf6stnqD+ET4=; b=kL6yimb56sf2jPJN3wnmtIw+1w PBUN2tCSiHTijSFrGS58+SvUKfbCiuCGM1ZqaS5LMjiMS+N5XvdQqOrm5L+ryjf2jAV8zkJyXsD23 nAD10DPouRxXOnRLJlqZPc4GS487golQhbmtuVgDDwc5xSXsYS65t+mmxxAqfzX8FYJY=; Received: from root (helo=callcc.thunk.org) by imap.thunk.org with local-esmtp (Exim 4.89) (envelope-from ) id 1gMNu7-00059z-Oq; Tue, 13 Nov 2018 01:54:11 +0000 Received: by callcc.thunk.org (Postfix, from userid 15806) id 652537A47B7; Mon, 12 Nov 2018 20:54:10 -0500 (EST) Date: Mon, 12 Nov 2018 20:54:10 -0500 From: "Theodore Y. Ts'o" To: Dave Chinner Cc: Joe Perches , Eric Sandeen , "Darrick J. Wong" , Christoph Hellwig , linux-xfs@vger.kernel.org, LKML Subject: Re: [PATCH] xfs: Remove noinline from #define STATIC Message-ID: <20181113015410.GB30750@thunk.org> Mail-Followup-To: "Theodore Y. Ts'o" , Dave Chinner , Joe Perches , Eric Sandeen , "Darrick J. Wong" , Christoph Hellwig , linux-xfs@vger.kernel.org, LKML References: <7302f4a13c1cbf62b07f636878ce25fcca84b6c4.camel@perches.com> <6420cf91-89c8-a876-7a0d-25ab8ba428b8@sandeen.net> <20181112214515.GN19305@dastard> <20181113011804.GP19305@dastard> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181113011804.GP19305@dastard> User-Agent: Mutt/1.10.1 (2018-07-13) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: tytso@thunk.org X-SA-Exim-Scanned: No (on imap.thunk.org); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 13, 2018 at 12:18:05PM +1100, Dave Chinner wrote: > I'm not interested in making code fast if distro support engineers > can't debug problems on user systems easily. Optimising for > performance over debuggability is a horrible trade off for us to > make because it means users and distros end up much more reliant on > single points of expertise for debugging problems. And that means > the majority of the load of problem triage falls directly on very > limited resources - the core XFS development team. A little bit of > thought about how to make code easier to triage and debug goes a > long, long way.... So at least in my experience, if the kernels are compiled with CONFIG_DEBUG_INFO and/or CONFIG_DEBUG_INFO_REDUCED, scripts/decode_stracktrace.sh seems to do a very nice job with inlined functions. Now, ext4 generally only has about 3 or 4 nested inlines, and so I don't know how it works with 20 or 30 nested inlined functions, so perhaps this is not applicable for XFS. But it perhaps toolchain technology has advanced since the Irix days such that it's no longer as necessary to force the non-inlining of functions for easing debugging? - Ted