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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 2A551C33C9E for ; Sat, 11 Jan 2020 10:25:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F37CF2082E for ; Sat, 11 Jan 2020 10:25:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578738329; bh=jV0Fn+92D1zShlnjiLkLneWO8c8R5+UdB7LDaQECXz8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=zxgD7PAmrrTxw0bJyzjiohc7wwZiSZivYpWhplhiLqEzKpgI0DagOesS6nv97+7M5 9numYxcr3J4K9Nk3+16FT1UTbQrs8oOYqpugdqHXZ81JjhQprXLZbQVIm5wUScNSJ6 UX+KpiUDzx2sZ4SsclbZSqmKXfhoGAtYR38GzHr0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730646AbgAKKZ2 (ORCPT ); Sat, 11 Jan 2020 05:25:28 -0500 Received: from mail.kernel.org ([198.145.29.99]:56178 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730662AbgAKKZZ (ORCPT ); Sat, 11 Jan 2020 05:25:25 -0500 Received: from localhost (unknown [62.119.166.9]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D93AA20848; Sat, 11 Jan 2020 10:25:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578738324; bh=jV0Fn+92D1zShlnjiLkLneWO8c8R5+UdB7LDaQECXz8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ADkuKq29ojjbrfn7VQEVde6E8+nsPm/lnJ9+K5m3zK1HARelSnnwQ9vrROOm4Se0n kG8VeugDzQZICiTjhX0DoR6U0HepeHLVpTyIQikKqfUUEqQOV1t/Fwcj7tD/rzuEg/ 2x9zzTG9/O+ggSf3alBT3W+bfw9R+wxz3rNay1Wg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Michael Petlan , Jiri Olsa , Arnaldo Carvalho de Melo , Sasha Levin Subject: [PATCH 5.4 057/165] perf header: Fix false warning when there are no duplicate cache entries Date: Sat, 11 Jan 2020 10:49:36 +0100 Message-Id: <20200111094926.006892306@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200111094921.347491861@linuxfoundation.org> References: <20200111094921.347491861@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 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