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 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 089B8C677F1 for ; Tue, 17 Jan 2023 15:18:03 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pHnhu-0004We-9u; Tue, 17 Jan 2023 10:17:02 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pHnhn-0004Vr-PB for qemu-devel@nongnu.org; Tue, 17 Jan 2023 10:16:55 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pHnhi-0002sE-SK for qemu-devel@nongnu.org; Tue, 17 Jan 2023 10:16:52 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1673968609; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=oas+znjzf+AP4bd/x5YD4nR2sJcjipvpxkKT4cCa4PQ=; b=FKNCzuMI/pzVI/Npwu73WVH4ylCmoZ30ymgYChjLjPV+bStJJaAhSqUcOGPA5V2ZYIm4jD UtS3F+vbdpNYImMvkxszhVkyZFYIm+vH2NPX/pRr9snyaTG5i83FA2r2MwJ4FkTqFoGngT iSPGAV609pPkhrBHz35Y+thLiLyupEE= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-22-RlMwqNhtNHeGZkFAEnrslA-1; Tue, 17 Jan 2023 10:16:25 -0500 X-MC-Unique: RlMwqNhtNHeGZkFAEnrslA-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 884BE80D180; Tue, 17 Jan 2023 15:01:08 +0000 (UTC) Received: from redhat.com (unknown [10.33.36.69]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 15AF3492B10; Tue, 17 Jan 2023 15:01:06 +0000 (UTC) Date: Tue, 17 Jan 2023 15:01:04 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Emanuele Giuseppe Esposito Cc: qemu-devel@nongnu.org, Warner Losh , Kyle Evans , Kevin Wolf , Stefan Hajnoczi , Paolo Bonzini , Alex =?utf-8?Q?Benn=C3=A9e?= , Thomas Huth , Richard Henderson Subject: Re: [PATCH 3/3] configure: Enable -Wthread-safety if present Message-ID: References: <20230117135203.3049709-1-eesposit@redhat.com> <20230117135203.3049709-4-eesposit@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: User-Agent: Mutt/2.2.9 (2022-11-12) X-Scanned-By: MIMEDefang 3.1 on 10.11.54.9 Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Tue, Jan 17, 2023 at 03:41:29PM +0100, Emanuele Giuseppe Esposito wrote: >=20 >=20 > Am 17/01/2023 um 15:02 schrieb Daniel P. Berrang=C3=A9: > > On Tue, Jan 17, 2023 at 08:52:03AM -0500, Emanuele Giuseppe Esposito wr= ote: > >> From: Kevin Wolf > >> > >> This enables clang's thread safety analysis (TSA), which we'll use to > >> statically check the block graph locking. > >> > >> Signed-off-by: Kevin Wolf > >> Message-Id: <20221207131838.239125-9-kwolf@redhat.com> > >> Reviewed-by: Emanuele Giuseppe Esposito > >> Signed-off-by: Kevin Wolf > >> --- > >> configure | 1 + > >> 1 file changed, 1 insertion(+) > >> > >> diff --git a/configure b/configure > >> index 2281892657..14668e6269 100755 > >> --- a/configure > >> +++ b/configure > >> @@ -1183,6 +1183,7 @@ add_to warn_flags -Wnested-externs > >> add_to warn_flags -Wendif-labels > >> add_to warn_flags -Wexpansion-to-defined > >> add_to warn_flags -Wimplicit-fallthrough=3D2 > >> +add_to warn_flags -Wthread-safety > >=20 > > Does this thread safety analysis have any kind of measurable > > impact on compilation speed ? > >=20 > > Our CI jobs are quite sensitive to any increase in build > > time. >=20 > From a quick run in my machine (Dell PowerEdge R440 with Intel(R) > Xeon(R) Gold 5120 CPU @ 2.20GHz, 28 cpus): >=20 > without clang: > real 2m46.729s=0F > =03user 19m24.122s=0F > =03sys 2m58.643s=0F >=20 > with clang: > real 2m45.204s > user 19m52.096s > sys 2m9.036s >=20 > So there should be no significative impact. >=20 > I also forgot to mention that this serie fixes the CI failure seen in: >=20 > https://gitlab.com/qemu-project/qemu/-/jobs/3479763741 > https://gitlab.com/qemu-project/qemu/-/jobs/3479763746 Odd, that job already has -Wthread-safety included in CFLAGS, which would seem to make this patch redundant, but I don't see where -Wthread-safety came from in that pipeline=20 With regards, Daniel --=20 |: https://berrange.com -o- https://www.flickr.com/photos/dberrange= :| |: https://libvirt.org -o- https://fstop138.berrange.com= :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange= :|