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=-18.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS 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 27321C433E0 for ; Sun, 17 Jan 2021 17:16:36 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id F1B162222B for ; Sun, 17 Jan 2021 17:16:34 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F1B162222B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=codefail.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4DJhR45QKrzDrfK for ; Mon, 18 Jan 2021 04:16:32 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=codefail.de (client-ip=131.153.2.45; helo=h4.fbrelay.privateemail.com; envelope-from=cmr@codefail.de; receiver=) Received: from h4.fbrelay.privateemail.com (h4.fbrelay.privateemail.com [131.153.2.45]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4DJhNn6VbPzDrVT for ; Mon, 18 Jan 2021 04:14:33 +1100 (AEDT) Received: from MTA-12-4.privateemail.com (mta-12.privateemail.com [198.54.127.105]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by h3.fbrelay.privateemail.com (Postfix) with ESMTPS id 16C65808CB for ; Sun, 17 Jan 2021 12:14:30 -0500 (EST) Received: from mta-12.privateemail.com (localhost [127.0.0.1]) by mta-12.privateemail.com (Postfix) with ESMTP id 27C67800BA; Sun, 17 Jan 2021 12:14:24 -0500 (EST) Received: from localhost (unknown [10.20.151.223]) by mta-12.privateemail.com (Postfix) with ESMTPA id E65EB80094; Sun, 17 Jan 2021 17:14:23 +0000 (UTC) Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8 Subject: Re: [PATCH v3 4/8] powerpc/signal64: Remove TM ifdefery in middle of if/else block From: "Christopher M. Riedl" To: "Christophe Leroy" , Date: Sun, 17 Jan 2021 11:16:12 -0600 Message-Id: In-Reply-To: <80d49969-880f-5161-c829-cf319f94351d@csgroup.eu> X-Virus-Scanned: ClamAV using ClamSMTP X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Mon Jan 11, 2021 at 7:29 AM CST, Christophe Leroy wrote: > > > Le 09/01/2021 =C3=A0 04:25, Christopher M. Riedl a =C3=A9crit : > > Rework the messy ifdef breaking up the if-else for TM similar to > > commit f1cf4f93de2f ("powerpc/signal32: Remove ifdefery in middle of if= /else"). > >=20 > > Unlike that commit for ppc32, the ifdef can't be removed entirely since > > uc_transact in sigframe depends on CONFIG_PPC_TRANSACTIONAL_MEM. > >=20 > > Signed-off-by: Christopher M. Riedl > > --- > > arch/powerpc/kernel/signal_64.c | 17 +++++++---------- > > 1 file changed, 7 insertions(+), 10 deletions(-) > >=20 > > diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/sign= al_64.c > > index b211a8ea4f6e..dd3787f67a78 100644 > > --- a/arch/powerpc/kernel/signal_64.c > > +++ b/arch/powerpc/kernel/signal_64.c > > @@ -710,9 +710,7 @@ SYSCALL_DEFINE0(rt_sigreturn) > > struct pt_regs *regs =3D current_pt_regs(); > > struct ucontext __user *uc =3D (struct ucontext __user *)regs->gpr[1= ]; > > sigset_t set; > > -#ifdef CONFIG_PPC_TRANSACTIONAL_MEM > > unsigned long msr; > > -#endif > > =20 > > /* Always make any pending restarted system calls return -EINTR */ > > current->restart_block.fn =3D do_no_restart_syscall; > > @@ -762,10 +760,12 @@ SYSCALL_DEFINE0(rt_sigreturn) > > * restore_tm_sigcontexts. > > */ > > regs->msr &=3D ~MSR_TS_MASK; > > +#endif > > =20 > > if (__get_user(msr, &uc->uc_mcontext.gp_regs[PT_MSR])) > > goto badframe; > > This means you are doing that __get_user() even when msr is not used. > That should be avoided. > Thanks, I moved it into the #ifdef block right above it instead for the next spin. > > if (MSR_TM_ACTIVE(msr)) { > > +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM > > /* We recheckpoint on return. */ > > struct ucontext __user *uc_transact; > > =20 > > @@ -778,9 +778,8 @@ SYSCALL_DEFINE0(rt_sigreturn) > > if (restore_tm_sigcontexts(current, &uc->uc_mcontext, > > &uc_transact->uc_mcontext)) > > goto badframe; > > - } else > > #endif > > - { > > + } else { > > /* > > * Fall through, for non-TM restore > > * > > @@ -818,10 +817,8 @@ int handle_rt_signal64(struct ksignal *ksig, sigse= t_t *set, > > unsigned long newsp =3D 0; > > long err =3D 0; > > struct pt_regs *regs =3D tsk->thread.regs; > > -#ifdef CONFIG_PPC_TRANSACTIONAL_MEM > > /* Save the thread's msr before get_tm_stackpointer() changes it */ > > - unsigned long msr =3D regs->msr; > > -#endif > > + unsigned long msr __maybe_unused =3D regs->msr; > > I don't thing __maybe_unused() is the right solution. > > I think MSR_TM_ACTIVE() should be fixed instead, either by changing it > into a static inline > function, or doing something similar to > https://github.com/linuxppc/linux/commit/05a4ab823983d9136a460b7b5e0d49ee= 709a6f86 > Agreed, I'll change MSR_TM_ACTIVE() to reference its argument in the macro. This keeps it consistent with all the other MSR_TM_* macros in reg.h. Probably better than changing it to static inline since that would mean changing all the macros too which seems unecessary. > > =20 > > frame =3D get_sigframe(ksig, tsk, sizeof(*frame), 0); > > if (!access_ok(frame, sizeof(*frame))) > > @@ -836,8 +833,9 @@ int handle_rt_signal64(struct ksignal *ksig, sigset= _t *set, > > /* Create the ucontext. */ > > err |=3D __put_user(0, &frame->uc.uc_flags); > > err |=3D __save_altstack(&frame->uc.uc_stack, regs->gpr[1]); > > -#ifdef CONFIG_PPC_TRANSACTIONAL_MEM > > + > > if (MSR_TM_ACTIVE(msr)) { > > +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM > > /* The ucontext_t passed to userland points to the second > > * ucontext_t (for transactional state) with its uc_link ptr. > > */ > > @@ -847,9 +845,8 @@ int handle_rt_signal64(struct ksignal *ksig, sigset= _t *set, > > tsk, ksig->sig, NULL, > > (unsigned long)ksig->ka.sa.sa_handler, > > msr); > > - } else > > #endif > > - { > > + } else { > > err |=3D __put_user(0, &frame->uc.uc_link); > > prepare_setup_sigcontext(tsk, 1); > > err |=3D setup_sigcontext(&frame->uc.uc_mcontext, tsk, ksig->sig, > >=20 > > Christophe