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=-3.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS,T_DKIMWL_WL_HIGH,URIBL_BLOCKED, 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 1AE2AC28CF6 for ; Wed, 1 Aug 2018 21:38:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 996E020844 for ; Wed, 1 Aug 2018 21:38:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="U+MlAdAh" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 996E020844 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732713AbeHAXZw (ORCPT ); Wed, 1 Aug 2018 19:25:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:40014 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732697AbeHAXZw (ORCPT ); Wed, 1 Aug 2018 19:25:52 -0400 Received: from jouet.infradead.org (unknown [179.97.41.186]) (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 37436208B0; Wed, 1 Aug 2018 21:38:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1533159484; bh=faHsTKkl12KXdN0odmnoI90v/m5YZShorBTNFkWoP+M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=U+MlAdAhuQGYi9fF7PINOv05iVBgq2AoSEIj9m8lULdWIczchtGxJmCB0NY7kR50T SYsCJRrN0CwqYhzFEDCGlD0YUj7U4s6HLNag7A5ETo6bU8xpzNtxmPq3mC7LzHiEfs ShoQPr3GhpfomZDeV94Gd/LGhEtZxFtRfsygTks4= From: Arnaldo Carvalho de Melo To: Ingo Molnar Cc: Clark Williams , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Christophe Leroy , Alexander Shishkin , Peter Zijlstra , linuxppc-dev@lists.ozlabs.org, Arnaldo Carvalho de Melo Subject: [PATCH 19/21] perf tools: Allow overriding MAX_NR_CPUS at compile time Date: Wed, 1 Aug 2018 18:36:46 -0300 Message-Id: <20180801213648.4814-20-acme@kernel.org> X-Mailer: git-send-email 2.14.4 In-Reply-To: <20180801213648.4814-1-acme@kernel.org> References: <20180801213648.4814-1-acme@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Christophe Leroy After update of kernel, the perf tool doesn't run anymore on my 32MB RAM powerpc board, but still runs on a 128MB RAM board: ~# strace perf execve("/usr/sbin/perf", ["perf"], [/* 12 vars */]) = -1 ENOMEM (Cannot allocate memory) --- SIGSEGV {si_signo=SIGSEGV, si_code=SI_KERNEL, si_addr=0} --- +++ killed by SIGSEGV +++ Segmentation fault objdump -x shows that .bss section has a huge size of 24Mbytes: 27 .bss 016baca8 101cebb8 101cebb8 001cd988 2**3 With especially the following objects having quite big size: 10205f80 l O .bss 00140000 runtime_cycles_stats 10345f80 l O .bss 00140000 runtime_stalled_cycles_front_stats 10485f80 l O .bss 00140000 runtime_stalled_cycles_back_stats 105c5f80 l O .bss 00140000 runtime_branches_stats 10705f80 l O .bss 00140000 runtime_cacherefs_stats 10845f80 l O .bss 00140000 runtime_l1_dcache_stats 10985f80 l O .bss 00140000 runtime_l1_icache_stats 10ac5f80 l O .bss 00140000 runtime_ll_cache_stats 10c05f80 l O .bss 00140000 runtime_itlb_cache_stats 10d45f80 l O .bss 00140000 runtime_dtlb_cache_stats 10e85f80 l O .bss 00140000 runtime_cycles_in_tx_stats 10fc5f80 l O .bss 00140000 runtime_transaction_stats 11105f80 l O .bss 00140000 runtime_elision_stats 11245f80 l O .bss 00140000 runtime_topdown_total_slots 11385f80 l O .bss 00140000 runtime_topdown_slots_retired 114c5f80 l O .bss 00140000 runtime_topdown_slots_issued 11605f80 l O .bss 00140000 runtime_topdown_fetch_bubbles 11745f80 l O .bss 00140000 runtime_topdown_recovery_bubbles This is due to commit 4d255766d28b1 ("perf: Bump max number of cpus to 1024"), because many tables are sized with MAX_NR_CPUS This patch gives the opportunity to redefine MAX_NR_CPUS via $ make EXTRA_CFLAGS=-DMAX_NR_CPUS=1 Signed-off-by: Christophe Leroy Cc: Alexander Shishkin Cc: Peter Zijlstra Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/r/20170922112043.8349468C57@po15668-vm-win7.idsi0.si.c-s.fr Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/perf.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/tools/perf/perf.h b/tools/perf/perf.h index d215714f48df..21bf7f5a3cf5 100644 --- a/tools/perf/perf.h +++ b/tools/perf/perf.h @@ -25,7 +25,9 @@ static inline unsigned long long rdclock(void) return ts.tv_sec * 1000000000ULL + ts.tv_nsec; } +#ifndef MAX_NR_CPUS #define MAX_NR_CPUS 1024 +#endif extern const char *input_name; extern bool perf_host, perf_guest; -- 2.14.4