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[209.132.180.67]) by mx.google.com with ESMTP id v71si4476243pgd.468.2019.08.16.14.02.31; Fri, 16 Aug 2019 14:02:46 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@joelfernandes.org header.s=google header.b=VqNOWEK5; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727772AbfHPVAQ (ORCPT + 99 others); Fri, 16 Aug 2019 17:00:16 -0400 Received: from mail-pg1-f193.google.com ([209.85.215.193]:45591 "EHLO mail-pg1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727548AbfHPVAQ (ORCPT ); Fri, 16 Aug 2019 17:00:16 -0400 Received: by mail-pg1-f193.google.com with SMTP id o13so3498826pgp.12 for ; Fri, 16 Aug 2019 14:00:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=CI/CZT0Ds4R/0RCpWk7/OcD9FklwQWMJXxVrdeA2FT0=; b=VqNOWEK5hlqwXwD3sdtXpJRuk5sL/zD8rB0xILprfdWdQBwwEbRKwmOnButLRaYajQ CFL1kZMw55YspiVvt93Z1ntrHW89OTGEidFneJC2UiNhDUTHVO8kAGzOxLg0I3G+Q1k6 4nK/q5xjdG2I3HSMZuo0kcmr8ptvN/HpzZ/TY= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=CI/CZT0Ds4R/0RCpWk7/OcD9FklwQWMJXxVrdeA2FT0=; b=riNCi1UDzGfmy0ogfNzGvu5xA4aB6//QmDU4tGcmPLn/6zjCsAXTCv4hKiz61u/aPK 6XFCnoNRBs/viLDdOuCMskX7rkLNiUGkGlWfh+rp9EtDbZZwv0hsF337XFHIKRBM9ruW OFNhDROAEDFS1cBA+2l4TKNM/P883x9fWw2RqKbxZosuBnkr2rTBBkZxwN/g8lvVVyZY pg6KLFByir2h57RET6JhFGWEeq4/WhqQCYFchHEKeRot/D2yFNoYBlVzOLOokLRTgVvb wLNQYXoYDIx7iWTgwcXezTn/lq3YP8Jgmqp9ceTdZQ9P75R3xbVLDD35FTnyNrFpADQz wesg== X-Gm-Message-State: APjAAAUopRaFV6ORm1afmvIHE3cBb5se9BcfJeYZoFZakR5kKvWNsyTT SHqerZm69MUpxEQyBx8g5cEO0g== X-Received: by 2002:a17:90a:d3c3:: with SMTP id d3mr9301430pjw.15.1565989215416; Fri, 16 Aug 2019 14:00:15 -0700 (PDT) Received: from localhost ([172.19.216.18]) by smtp.gmail.com with ESMTPSA id d3sm9074576pjz.31.2019.08.16.14.00.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 16 Aug 2019 14:00:14 -0700 (PDT) Date: Fri, 16 Aug 2019 16:59:57 -0400 From: Joel Fernandes To: Steven Rostedt Cc: Alan Stern , Mathieu Desnoyers , Valentin Schneider , linux-kernel , Peter Zijlstra , Thomas Gleixner , paulmck , Boqun Feng , Will Deacon , David Howells , Linus Torvalds Subject: Re: [PATCH 1/1] Fix: trace sched switch start/stop racy updates Message-ID: <20190816205957.GG10481@google.com> References: <241506096.21688.1565977319832.JavaMail.zimbra@efficios.com> <20190816164912.078b6e01@oasis.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190816164912.078b6e01@oasis.local.home> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Aug 16, 2019 at 04:49:12PM -0400, Steven Rostedt wrote: > On Fri, 16 Aug 2019 16:44:10 -0400 > Joel Fernandes wrote: > > > > I am also more on the side of using *_ONCE. To me, by principal, I > > would be willing to convert any concurrent plain access using _ONCE, > > just so we don't have to worry about it now or in the future and also > > documents the access. > > > > Perhaps the commit message can be reworded to mention that the _ONCE > > is an additional clean up for safe access. > > The most I'll take is two separate patches. One is going to be marked > for stable as it fixes a real bug. The other is more for cosmetic or > theoretical issues, that I will state clearly "NOT FOR STABLE", such > that the autosel doesn't take them. Makes sense to me! thanks, - Joel