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=-11.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 3C138C43603 for ; Wed, 11 Dec 2019 14:54:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0715E214AF for ; Wed, 11 Dec 2019 14:54:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="KcIjVllt" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729608AbfLKOy5 (ORCPT ); Wed, 11 Dec 2019 09:54:57 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:55851 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728370AbfLKOyy (ORCPT ); Wed, 11 Dec 2019 09:54:54 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1576076093; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=VKMysQNz3mfKWf0j//V+OPBl+nUoNAG3+S9K2zyK5z4=; b=KcIjVlltcgtpFgsro8cb+R2pDO3jmQYrakUWQcimarq/69arw0LA98Mpuf7oTY0t85vEWP GVWekbVjCtXrlyUlOd+fg8AW4WbAJ0hFwxIClhxDi3iBS16jWq79PCjANcsyNwRq+Jq1oX 1GPFf2RQOA29r3D4f1VAGpU7XFpDw3c= 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-45-SbcqDtOEMA2V9my8zz4x5A-1; Wed, 11 Dec 2019 09:54:46 -0500 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 C88DE100A172; Wed, 11 Dec 2019 14:54:44 +0000 (UTC) Received: from krava (unknown [10.43.17.106]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 85A7560BE0; Wed, 11 Dec 2019 14:54:42 +0000 (UTC) Date: Wed, 11 Dec 2019 15:54:40 +0100 From: Jiri Olsa To: Arnaldo Carvalho de Melo Cc: John Garry , Peter Zijlstra , Ingo Molnar , Alexander Shishkin , Namhyung Kim , mark.rutland@arm.com, will@kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Linuxarm , linux-perf-users@vger.kernel.org Subject: Re: [PATCHES] Fix 'perf top' breakage on architectures not providing get_cpuid() Re: perf top for arm64? Message-ID: <20191211145440.GD25474@krava> References: <1573045254-39833-1-git-send-email-john.garry@huawei.com> <20191106140036.GA6259@kernel.org> <418023e7-a50d-cb6f-989f-2e6d114ce5d8@huawei.com> <20191210163655.GG14123@krava> <952dc484-2739-ee65-f41c-f0198850ab10@huawei.com> <20191210170841.GA23357@krava> <9a31536b-f266-e305-1107-2f745d0a33e3@huawei.com> <20191210195113.GD13965@kernel.org> <20191211133319.GA15181@kernel.org> MIME-Version: 1.0 In-Reply-To: <20191211133319.GA15181@kernel.org> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-MC-Unique: SbcqDtOEMA2V9my8zz4x5A-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Dec 11, 2019 at 10:33:19AM -0300, Arnaldo Carvalho de Melo wrote: > Em Tue, Dec 10, 2019 at 04:51:13PM -0300, Arnaldo Carvalho de Melo escrev= eu: > > Em Tue, Dec 10, 2019 at 05:17:56PM +0000, John Garry escreveu: > > > On 10/12/2019 17:08, Jiri Olsa wrote: > > > > On Tue, Dec 10, 2019 at 04:52:52PM +0000, John Garry wrote: > > > > > On 10/12/2019 16:36, Jiri Olsa wrote: > > > > > > On Tue, Dec 10, 2019 at 04:13:49PM +0000, John Garry wrote: > > > > > > > I find to my surprise that "perf top" does not work for arm64= : >=20 > > > > > > > root@ubuntu:/home/john/linux# tools/perf/perf top > > > > > > > Couldn't read the cpuid for this machine: No such file or dir= ectory >=20 > > > > > > there was recent change that check on cpuid and quits: > > > > > > 608127f73779 perf top: Initialize perf_env->cpuid, needed b= y the per arch annotation init routine >=20 > > > > > ok, this is new code. I obviously didn't check the git history... >=20 > > > > > But, apart from this, there are many other places where get_cpuid= () is > > > > > called. I wonder what else we're missing out on, and whether we s= hould still > > > > > add it. >=20 > > > > right, I was just wondering how come vendor events are working for = you, > > > > but realized we have get_cpuid_str being called in there ;-) >=20 > > > > I think we should add it as you have it prepared already, > > > > could you post it with bigger changelog that would explain > > > > where it's being used for arm? >=20 > > > ok, I can look to do that. >=20 > > > But, as you know, we still need to fix perf top for other architectur= es > > > affected. >=20 > > Right, I need to make that just a pr_debug() message and then check in > > the annotation code when that is needed to see if it is set, if not, > > then show a popup error message and refuse to do whatever annotation > > feature requires that. >=20 > > Anyway, your patch should make sense and provide info that the ARM64 > > annotation may use now or in the future. >=20 > So can you take a look at the two patches below and provide me Acked-by > and/or Reviewed-by and/or Tested-by? looks good to me, but don't have arm server at the moment.. Acked-by: Jiri Olsa thanks, jirka >=20 >=20 > From 53c6cde6a71a1a9283763bd2e938b229b50c2cd5 Mon Sep 17 00:00:00 2001 > From: Arnaldo Carvalho de Melo > Date: Wed, 11 Dec 2019 10:09:24 -0300 > Subject: [PATCH 1/2] perf arch: Make the default get_cpuid() return compa= tible > error >=20 > Some of the functions calling get_cpuid() propagate back the error it > returns, and all are using errno (positive) values, make the weak > default get_cpuid() function return ENOSYS to be consistent and to allow > checking if this is an arch not providing this function or if a provided > one is having trouble getting the cpuid, to decide if the warning should > be provided to the user or just a debug message should be emitted. >=20 > Cc: Adrian Hunter > Cc: Jiri Olsa > Cc: John Garry > Cc: Mark Rutland > Cc: Namhyung Kim > Cc: Will Deacon > Link: https://lkml.kernel.org/n/tip-lxwjr0cd2eggzx04a780ffrv@git.kernel.o= rg > Signed-off-by: Arnaldo Carvalho de Melo > --- > tools/perf/util/header.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) >=20 > diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c > index becc2d109423..4d39a75551a0 100644 > --- a/tools/perf/util/header.c > +++ b/tools/perf/util/header.c > @@ -850,7 +850,7 @@ int __weak strcmp_cpuid_str(const char *mapcpuid, con= st char *cpuid) > */ > int __weak get_cpuid(char *buffer __maybe_unused, size_t sz __maybe_unus= ed) > { > -=09return -1; > +=09return ENOSYS; /* Not implemented */ > } > =20 > static int write_cpuid(struct feat_fd *ff, > --=20 > 2.21.0 >=20 > From c6c6a3e2eb6982e37294abcac389effd298cf730 Mon Sep 17 00:00:00 2001 > From: Arnaldo Carvalho de Melo > Date: Wed, 11 Dec 2019 10:21:59 -0300 > Subject: [PATCH 2/2] perf top: Do not bail out when perf_env__read_cpuid(= ) > returns ENOSYS >=20 > 'perf top' stopped working on hw architectures that do not provide a > get_cpuid() implementation and thus fallback to the weak get_cpuid() > default function. >=20 > This is done because at annotation time we may need it in the arch > specific annotation init routine, but that is only being used by arches > that do provide a get_cpuid() implementation: >=20 > $ find tools/ -name "*.[ch]" | xargs grep 'evlist->env' > tools/perf/builtin-top.c:=09top.evlist->env =3D &perf_env; > tools/perf/util/evsel.c:=09=09return evsel->evlist->env; > tools/perf/util/s390-cpumsf.c:=09sf->machine_type =3D s390_cpumsf_get_t= ype(session->evlist->env->cpuid); > tools/perf/util/header.c:=09session->evlist->env =3D &header->env; > tools/perf/util/sample-raw.c:=09const char *arch_pf =3D perf_env__arch(= evlist->env); > $ >=20 > $ find tools/perf/arch -name "*.[ch]" | xargs grep -w get_cpuid > tools/perf/arch/x86/util/auxtrace.c:=09ret =3D get_cpuid(buffer, sizeof= (buffer)); > tools/perf/arch/x86/util/header.c:get_cpuid(char *buffer, size_t sz) > tools/perf/arch/powerpc/util/header.c:get_cpuid(char *buffer, size_t sz= ) > tools/perf/arch/s390/util/header.c: * Implementation of get_cpuid(). > tools/perf/arch/s390/util/header.c:int get_cpuid(char *buffer, size_t s= z) > tools/perf/arch/s390/util/header.c:=09if (buf && get_cpuid(buf, 128)) > $ >=20 > For 'report' or 'script', i.e. tools working on perf.data files, that is > setup while reading the header, its just top that needs to explicitely > read it at tool start. >=20 > Reported-by: John Garry > Analysed-by: Jiri Olsa > Cc: Adrian Hunter > Cc: Mark Rutland > Cc: Namhyung Kim > Cc: Will Deacon > Link: https://lkml.kernel.org/n/tip-lxwjr0cd2eggzx04a780ffrv@git.kernel.o= rg > Signed-off-by: Arnaldo Carvalho de Melo > --- > tools/perf/builtin-top.c | 10 +++++++--- > 1 file changed, 7 insertions(+), 3 deletions(-) >=20 > diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c > index dc80044bc46f..795e353de095 100644 > --- a/tools/perf/builtin-top.c > +++ b/tools/perf/builtin-top.c > @@ -1568,9 +1568,13 @@ int cmd_top(int argc, const char **argv) > =09 */ > =09status =3D perf_env__read_cpuid(&perf_env); > =09if (status) { > -=09=09pr_err("Couldn't read the cpuid for this machine: %s\n", > -=09=09 str_error_r(errno, errbuf, sizeof(errbuf))); > -=09=09goto out_delete_evlist; > +=09=09/* > +=09=09 * Some arches do not provide a get_cpuid(), so just use pr_debug,= otherwise > +=09=09 * warn the user explicitely. > +=09=09 */ > +=09=09eprintf(status =3D=3D ENOSYS ? 1 : 0, verbose, > +=09=09=09"Couldn't read the cpuid for this machine: %s\n", > +=09=09=09str_error_r(errno, errbuf, sizeof(errbuf))); > =09} > =09top.evlist->env =3D &perf_env; > =20 > --=20 > 2.21.0 >=20