From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752015AbcISOqg (ORCPT ); Mon, 19 Sep 2016 10:46:36 -0400 Received: from mail.southpole.se ([37.247.8.11]:36450 "EHLO mail.southpole.se" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751579AbcISOqd (ORCPT ); Mon, 19 Sep 2016 10:46:33 -0400 Subject: Re: [PATCH 4/7] openrisc: Add thread-local storage (TLS) support To: Stafford Horne , Stefan Kristiansson , Andrew Morton References: <1474036985-20981-1-git-send-email-shorne@gmail.com> <1474036985-20981-5-git-send-email-shorne@gmail.com> Cc: linux-kernel@vger.kernel.org, Christian Svensson From: Jonas Bonn Message-ID: <57DFF544.3060709@southpole.se> Date: Mon, 19 Sep 2016 16:25:08 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: <1474036985-20981-5-git-send-email-shorne@gmail.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-Assp-Version: 2.5.1(16177) on assp.southpole.se X-Assp-ID: assp.southpole.se 95110-04386 X-Assp-Session: 7F0FD2036CD8 (mail 1) X-Assp-Client-SSL: yes X-Assp-Server-TLS: yes Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/16/2016 04:43 PM, Stafford Horne wrote: > From: Christian Svensson > > Historically OpenRISC GCC has reserved r10 which we now use to hold > the thread pointer for thread-local storage (TLS). I know this was proposed by way of this patch, but we deferred accepting this until the OpenRISC spec could be updated accordingly. Has this been done now? If not, still NAK. /Jonas > > Signed-off-by: Christian Svensson > Signed-off-by: Stefan Kristiansson > Signed-off-by: Stafford Horne > --- > arch/openrisc/kernel/process.c | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/arch/openrisc/kernel/process.c b/arch/openrisc/kernel/process.c > index 7095dfe..277123b 100644 > --- a/arch/openrisc/kernel/process.c > +++ b/arch/openrisc/kernel/process.c > @@ -173,6 +173,19 @@ copy_thread(unsigned long clone_flags, unsigned long usp, > > if (usp) > userregs->sp = usp; > + > + /* > + * For CLONE_SETTLS set "tp" (r10) to the TLS pointer passed to sys_clone. > + * > + * The kernel entry is: > + * int clone (long flags, void *child_stack, int *parent_tid, > + * int *child_tid, struct void *tls) > + * > + * This makes the source r7 in the kernel registers. > + */ > + if (clone_flags & CLONE_SETTLS) > + userregs->gpr[10] = userregs->gpr[7]; > + > userregs->gpr[11] = 0; /* Result from fork() */ > > kregs->gpr[20] = 0; /* Userspace thread */