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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 7F888C2D0C6 for ; Fri, 27 Dec 2019 17:55:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5AA36208C4 for ; Fri, 27 Dec 2019 17:55:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1577469301; bh=jV0Fn+92D1zShlnjiLkLneWO8c8R5+UdB7LDaQECXz8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=rB9vN/kWgGZ4BuaIQtpafNQ3hg7LgLmENRlVwKOJMfG2+F3kEi+1kzZJjTmX3dA+4 3G+tDKsw5ZvzHUzVOipZxSnnpZ4wseDEG2RaL+2ROHjEtuijkLJE86Sj8bjdzRzmku GzcCxsfbC5BDyBOO0pQ8U/6WCf4bwaUiRPP3u6rI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728179AbfL0Ryz (ORCPT ); Fri, 27 Dec 2019 12:54:55 -0500 Received: from mail.kernel.org ([198.145.29.99]:39374 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727361AbfL0Rm2 (ORCPT ); Fri, 27 Dec 2019 12:42:28 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 623A124654; Fri, 27 Dec 2019 17:42:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1577468548; bh=jV0Fn+92D1zShlnjiLkLneWO8c8R5+UdB7LDaQECXz8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=P6dKqBrRRbDkPe8GU2r6UvAK7TMOPCYJw+q4s9nL0IwnUWGW5eXCRpsXuOrGd+zqz VHLPmJ7mkAbf05tYl0qqjkSRKpCsTH/y1bypGXyNImZPZXBS6yP7iJ2i7zGIbOHxa3 m/UFudYQfUsUx0fi1pnjQrRwze7LyNLWtq2S+xX0= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Michael Petlan , Jiri Olsa , Arnaldo Carvalho de Melo , Sasha Levin Subject: [PATCH AUTOSEL 5.4 075/187] perf header: Fix false warning when there are no duplicate cache entries Date: Fri, 27 Dec 2019 12:39:03 -0500 Message-Id: <20191227174055.4923-75-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191227174055.4923-1-sashal@kernel.org> References: <20191227174055.4923-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Michael Petlan [ Upstream commit 28707826877f84bce0977845ea529cbdd08e4e8d ] Before this patch, perf expected that there might be NPROC*4 unique cache entries at max, however, it also expected that some of them would be shared and/or of the same size, thus the final number of entries would be reduced to be lower than NPROC*4. In case the number of entries hadn't been reduced (was NPROC*4), the warning was printed. However, some systems might have unusual cache topology, such as the following two-processor KVM guest: cpu level shared_cpu_list size 0 1 0 32K 0 1 0 64K 0 2 0 512K 0 3 0 8192K 1 1 1 32K 1 1 1 64K 1 2 1 512K 1 3 1 8192K This KVM guest has 8 (NPROC*4) unique cache entries, which used to make perf printing the message, although there actually aren't "way too many cpu caches". v2: Removing unused argument. v3: Unifying the way we obtain number of cpus. v4: Removed '& UINT_MAX' construct which is redundant. Signed-off-by: Michael Petlan Acked-by: Jiri Olsa LPU-Reference: 20191208162056.20772-1-mpetlan@redhat.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin --- tools/perf/util/header.c | 21 ++++++--------------- 1 file changed, 6 insertions(+), 15 deletions(-) diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c index becc2d109423..d3412f2c0d18 100644 --- a/tools/perf/util/header.c +++ b/tools/perf/util/header.c @@ -1089,21 +1089,18 @@ static void cpu_cache_level__fprintf(FILE *out, struct cpu_cache_level *c) fprintf(out, "L%d %-15s %8s [%s]\n", c->level, c->type, c->size, c->map); } -static int build_caches(struct cpu_cache_level caches[], u32 size, u32 *cntp) +#define MAX_CACHE_LVL 4 + +static int build_caches(struct cpu_cache_level caches[], u32 *cntp) { u32 i, cnt = 0; - long ncpus; u32 nr, cpu; u16 level; - ncpus = sysconf(_SC_NPROCESSORS_CONF); - if (ncpus < 0) - return -1; - - nr = (u32)(ncpus & UINT_MAX); + nr = cpu__max_cpu(); for (cpu = 0; cpu < nr; cpu++) { - for (level = 0; level < 10; level++) { + for (level = 0; level < MAX_CACHE_LVL; level++) { struct cpu_cache_level c; int err; @@ -1123,18 +1120,12 @@ static int build_caches(struct cpu_cache_level caches[], u32 size, u32 *cntp) caches[cnt++] = c; else cpu_cache_level__free(&c); - - if (WARN_ONCE(cnt == size, "way too many cpu caches..")) - goto out; } } - out: *cntp = cnt; return 0; } -#define MAX_CACHE_LVL 4 - static int write_cache(struct feat_fd *ff, struct evlist *evlist __maybe_unused) { @@ -1143,7 +1134,7 @@ static int write_cache(struct feat_fd *ff, u32 cnt = 0, i, version = 1; int ret; - ret = build_caches(caches, max_caches, &cnt); + ret = build_caches(caches, &cnt); if (ret) goto out; -- 2.20.1