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=-5.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 ABF86C433DF for ; Thu, 15 Oct 2020 14:34:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4D5E7218AC for ; Thu, 15 Oct 2020 14:34:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="B1EJPJon" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388305AbgJOOeU (ORCPT ); Thu, 15 Oct 2020 10:34:20 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:36950 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387589AbgJOOeT (ORCPT ); Thu, 15 Oct 2020 10:34:19 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1602772458; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=jJjIXiJnVqHKp5XONa8t2m4dwK//7P5N/0nBKHq4J+E=; b=B1EJPJonRFnYOemFUqIS7F68UThbGJExsFGuxD7GnEgVNn/QKWxr7JcP4buKkJCTI4SMsg jQpEabiLhJnltZbB3Hw0uuP7476r1Ecs52dbzKd1UrzSIHM+9FFfgv2W+KTBSZ3M9IJtpP 8wJP31fHU4DLYm1iPtm/ZhhSdeAL57Q= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-341-qU_iVLrJPhuSWzNZPJjCHA-1; Thu, 15 Oct 2020 10:34:14 -0400 X-MC-Unique: qU_iVLrJPhuSWzNZPJjCHA-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id EC7E41018F77; Thu, 15 Oct 2020 14:34:12 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.40.193.8]) by smtp.corp.redhat.com (Postfix) with SMTP id 64D93610F3; Thu, 15 Oct 2020 14:34:11 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Thu, 15 Oct 2020 16:34:12 +0200 (CEST) Date: Thu, 15 Oct 2020 16:34:10 +0200 From: Oleg Nesterov To: Thomas Gleixner Cc: Jens Axboe , linux-kernel@vger.kernel.org, io-uring@vger.kernel.org, peterz@infradead.org Subject: Re: [PATCH 4/5] x86: wire up TIF_NOTIFY_SIGNAL Message-ID: <20201015143409.GC24156@redhat.com> References: <20201015131701.511523-1-axboe@kernel.dk> <20201015131701.511523-5-axboe@kernel.dk> <87o8l3a8af.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87o8l3a8af.fsf@nanos.tec.linutronix.de> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 10/15, Thomas Gleixner wrote: > > On Thu, Oct 15 2020 at 07:17, Jens Axboe wrote: > > --- a/arch/x86/kernel/signal.c > > +++ b/arch/x86/kernel/signal.c > > @@ -808,7 +808,10 @@ void arch_do_signal(struct pt_regs *regs, unsigned long ti_work) > > { > > struct ksignal ksig; > > > > - if (get_signal(&ksig)) { > > + if (ti_work & _TIF_NOTIFY_SIGNAL) > > + tracehook_notify_signal(); > > + > > + if ((ti_work & _TIF_SIGPENDING) && get_signal(&ksig)) { > > /* Whee! Actually deliver the signal. */ > > handle_signal(&ksig, regs); > > return; > > Instead of adding this to every architectures signal magic, we can > handle TIF_NOTIFY_SIGNAL in the core code: > > static void handle_singal_work(ti_work, regs) > { > if (ti_work & _TIF_NOTIFY_SIGNAL) > tracehook_notify_signal(); > > arch_do_signal(ti_work, regs); > } > > loop { > if (ti_work & (SIGPENDING | NOTIFY_SIGNAL)) > handle_signal_work(ti_work, regs); > } To me this looks like unnecessary complication. We need to change every architecture anyway, how can this helper help? Oleg.