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=-2.1 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIM_INVALID, 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 9745EC6778F for ; Mon, 9 Jul 2018 09:01:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4348A20673 for ; Mon, 9 Jul 2018 09:01:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="VbneHFr5" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4348A20673 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org 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 S932674AbeGIJBr (ORCPT ); Mon, 9 Jul 2018 05:01:47 -0400 Received: from merlin.infradead.org ([205.233.59.134]:47486 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754383AbeGIJBq (ORCPT ); Mon, 9 Jul 2018 05:01:46 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; 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=x3Okx+kzlcXDnImI6WYyQ0rHnxrrMiafnZefmTC0SYo=; b=VbneHFr5oX8SD2L5p/Chm8o9n U23HvjOtB0dl2vbAF0zUMOepbOVMqj/SUkdepDyBpPIfTG7XGsuLpTtiu4iKcDcR5uLRhw2eGQ/ai jSeHfPzz+1rnh77snoMi4wne8+U9GkFwbIwbygMwHRcIx6Nbw/c5zNWgUgWyeUED23Vdglol4KfM8 F1QFqP/SZt/5TmMxzHy75U8//uGlxw7hQgZBGDb++cSBIgIFf0PKQqkxnUT0oDZXyHOlFJdW7Twd/ q31K7z1LSJoVGnEp023SGVsRVnfVixna+fzkbbMV/1hNIUT8rr0/DA4ldXudxqVr+k3VQ8ErSJznN uop+NGmew==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1fcS3D-0005Yq-Br; Mon, 09 Jul 2018 09:01:43 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id BBBD52028932D; Mon, 9 Jul 2018 11:01:41 +0200 (CEST) Date: Mon, 9 Jul 2018 11:01:41 +0200 From: Peter Zijlstra To: Sebastian Andrzej Siewior Cc: linux-kernel@vger.kernel.org, Ingo Molnar , Thomas Gleixner Subject: Re: [PATCH] sched/core: remove get_cpu() from sched_fork() Message-ID: <20180709090141.GE2476@hirez.programming.kicks-ass.net> References: <20180706130615.g2ex2kmfu5kcvlq6@linutronix.de> <20180706131808.GM2494@hirez.programming.kicks-ass.net> <20180706133200.a5n47p6utvil4bvf@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180706133200.a5n47p6utvil4bvf@linutronix.de> User-Agent: Mutt/1.10.0 (2018-05-17) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 06, 2018 at 03:32:00PM +0200, Sebastian Andrzej Siewior wrote: > On 2018-07-06 15:18:08 [+0200], Peter Zijlstra wrote: > > On Fri, Jul 06, 2018 at 03:06:15PM +0200, Sebastian Andrzej Siewior wrote: > > > Based on this it is possible to remove get_cpu() and use > > > smp_processor_id() for the `cpu' variable without breaking anything. > > > > Almost.. I think, see init_task_preempt_count(). > > #define init_task_preempt_count(p) do { \ > task_thread_info(p)->preempt_count = FORK_PREEMPT_COUNT; \ > } while (0) > > and task_thread_info() references p only. It looks good, what did I > miss? Argh, dammit, I read that with p == current :/ Then yes, looks ok.