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 6BC4FC433DF for ; Fri, 9 Oct 2020 14:43:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 145C822260 for ; Fri, 9 Oct 2020 14:43:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Bca5jZRU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388812AbgJIOnh (ORCPT ); Fri, 9 Oct 2020 10:43:37 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:33127 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388799AbgJIOng (ORCPT ); Fri, 9 Oct 2020 10:43:36 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1602254615; 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=2YtzdHcUrgnGAZg77pGxmadi1QZznT8bseJbL6oBoTA=; b=Bca5jZRU+n3uZsy6/2R9NB+DznscqeO1eKaJ6cmTWQpa3zdTzSaRdALwpn/rCRALyY0DJC ttPRZZ4Q9Cn6RQGghwfpdWGV37qj6eR7R4nrmT9newJOALq1QAudb36cMUoJnvp7VOyZ3k 4ZlH/lxoHgPUJLvxFvtUCC/RRIjiaGk= 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-281-oHku6ZAIMKCXoavSg-EiLg-1; Fri, 09 Oct 2020 10:43:33 -0400 X-MC-Unique: oHku6ZAIMKCXoavSg-EiLg-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 0123D80401F; Fri, 9 Oct 2020 14:43:32 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.40.195.138]) by smtp.corp.redhat.com (Postfix) with SMTP id 6B3656EF75; Fri, 9 Oct 2020 14:43:30 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Fri, 9 Oct 2020 16:43:31 +0200 (CEST) Date: Fri, 9 Oct 2020 16:43:29 +0200 From: Oleg Nesterov To: Jens Axboe Cc: linux-kernel@vger.kernel.org, io-uring@vger.kernel.org, peterz@infradead.org, tglx@linutronix.de Subject: Re: [PATCH 3/4] kernel: add support for TIF_NOTIFY_SIGNAL Message-ID: <20201009144328.GB14523@redhat.com> References: <20201008152752.218889-1-axboe@kernel.dk> <20201008152752.218889-4-axboe@kernel.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201008152752.218889-4-axboe@kernel.dk> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Once again, I am fine with this patch, just a minor comment... On 10/08, 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) > { > struct ksignal ksig; > > - if (get_signal(&ksig)) { > + if (test_thread_flag(TIF_NOTIFY_SIGNAL)) > + tracehook_notify_signal(); > + > + if (task_sigpending(current) && get_signal(&ksig)) { I suggested to change arch_do_signal() because somehow I like it this way ;) And because we can easily pass the "ti_work" mask to arch_do_signal() and avoid test_thread_flag/task_sigpending. Hmm. I just noticed that only x86 uses arch_do_signal(), so perhaps you can add this change to this patch right now? Up to you. On the other hand, we could add if (test_thread_flag(TIF_NOTIFY_SIGNAL)) tracehook_notify_signal(); if (!task_sigpending(current)) return 0; at the start of get_signal() instead. Somehow I don't really like this, but this way we do need less changes in arch-dependant code. Again, up to you. Oleg.