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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 BF61BC00449 for ; Wed, 3 Oct 2018 06:00:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7A46620878 for ; Wed, 3 Oct 2018 06:00:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7A46620878 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=c-s.fr 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 S1726739AbeJCMrs (ORCPT ); Wed, 3 Oct 2018 08:47:48 -0400 Received: from pegase1.c-s.fr ([93.17.236.30]:58252 "EHLO pegase1.c-s.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726432AbeJCMrs (ORCPT ); Wed, 3 Oct 2018 08:47:48 -0400 Received: from localhost (mailhub1-int [192.168.12.234]) by localhost (Postfix) with ESMTP id 42Q53q1Cj4z9ttBf; Wed, 3 Oct 2018 08:00:55 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at c-s.fr Received: from pegase1.c-s.fr ([192.168.12.234]) by localhost (pegase1.c-s.fr [192.168.12.234]) (amavisd-new, port 10024) with ESMTP id URNktn2kN_6n; Wed, 3 Oct 2018 08:00:43 +0200 (CEST) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase1.c-s.fr (Postfix) with ESMTP id 42Q53b4F02z9ttBW; Wed, 3 Oct 2018 08:00:43 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id D7BFE8B8B5; Wed, 3 Oct 2018 08:00:43 +0200 (CEST) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id PN9OyHphuYnA; Wed, 3 Oct 2018 08:00:43 +0200 (CEST) Received: from PO15451 (po15451.idsi0.si.c-s.fr [172.25.231.3]) by messagerie.si.c-s.fr (Postfix) with ESMTP id A0C2B8B74C; Wed, 3 Oct 2018 08:00:43 +0200 (CEST) Subject: Re: [RFC PATCH v3 5/7] powerpc: 'current_set' is now a table of task_struct pointers To: Nicholas Piggin Cc: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , aneesh.kumar@linux.vnet.ibm.com, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org References: <20181003154101.0b46956d@roar.ozlabs.ibm.com> From: Christophe LEROY Message-ID: <0336ff43-55ac-067b-23a9-4cb4b2fd38f3@c-s.fr> Date: Wed, 3 Oct 2018 08:00:43 +0200 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20181003154101.0b46956d@roar.ozlabs.ibm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: fr Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Le 03/10/2018 à 07:41, Nicholas Piggin a écrit : > On Mon, 1 Oct 2018 12:30:27 +0000 (UTC) > Christophe Leroy wrote: > >> The table of pointers 'current_set' has been used for retrieving >> the stack and current. They used to be thread_info pointers as >> they were pointing to the stack and current was taken from the >> 'task' field of the thread_info. >> >> Now, the pointers of 'current_set' table are now both pointers >> to task_struct and pointers to thread_info. >> >> As they are used to get current, and the stack pointer is >> retrieved from current's stack field, this patch changes >> their type to task_struct, and renames secondary_ti to >> secondary_current. > > I'm not sure if current_set is actually needed is it? Because > 64-bit already initializes paca->ksave / PACAKSAVE. That might > be a cleanup to do after your series. head_64.S contains: __secondary_start: /* Set thread priority to MEDIUM */ HMT_MEDIUM /* Initialize the kernel stack */ LOAD_REG_ADDR(r3, current_set) sldi r28,r24,3 /* get current_set[cpu#] */ ldx r14,r3,r28 addi r14,r14,THREAD_SIZE-STACK_FRAME_OVERHEAD std r14,PACAKSAVE(r13) 32-bit doesn't seem to use it, it only uses secondary_ti it seems. > > Reviewed-by: Nicholas Piggin > Christophe