Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757149Ab1CaMlw (ORCPT ); Thu, 31 Mar 2011 08:41:52 -0400 Received: from hera.kernel.org ([140.211.167.34]:56808 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752409Ab1CaMlv (ORCPT ); Thu, 31 Mar 2011 08:41:51 -0400 Date: Thu, 31 Mar 2011 12:41:31 GMT From: tip-bot for Frederic Weisbecker Cc: linux-kernel@vger.kernel.org, eranian@google.com, paulus@samba.org, acme@redhat.com, hpa@zytor.com, mingo@redhat.com, a.p.zijlstra@chello.nl, fweisbec@gmail.com, tglx@linutronix.de, mingo@elte.hu Reply-To: mingo@redhat.com, hpa@zytor.com, acme@redhat.com, paulus@samba.org, eranian@google.com, linux-kernel@vger.kernel.org, fweisbec@gmail.com, a.p.zijlstra@chello.nl, tglx@linutronix.de, mingo@elte.hu In-Reply-To: <1301535324-9735-1-git-send-email-fweisbec@gmail.com> References: <1301535324-9735-1-git-send-email-fweisbec@gmail.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/urgent] perf: mmap 512 kiB by default Message-ID: Git-Commit-ID: 800cd25c12981c99e5401c3551ffffd99f1c6c85 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.3 (hera.kernel.org [127.0.0.1]); Thu, 31 Mar 2011 12:41:32 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2420 Lines: 62 Commit-ID: 800cd25c12981c99e5401c3551ffffd99f1c6c85 Gitweb: http://git.kernel.org/tip/800cd25c12981c99e5401c3551ffffd99f1c6c85 Author: Frederic Weisbecker AuthorDate: Thu, 31 Mar 2011 03:35:24 +0200 Committer: Ingo Molnar CommitDate: Thu, 31 Mar 2011 13:02:55 +0200 perf: mmap 512 kiB by default The default setting of perf record is to mmap 128 pages if the user did not override with -m. However the page size may vary accross different architecture settings, giving different default size between each. Moreover the kernel side still has a default max number of mlocked pages of 512 kiB + 1 page for unprivileged users. 128 + 1 pages with page size > 4096 overlaps this threshold. Thus, better adapt to this limitation and set the default number of pages to fit those 512 kiB + 1 page. Signed-off-by: Frederic Weisbecker Signed-off-by: Peter Zijlstra Cc: Arnaldo Carvalho de Melo Cc: Paul Mackerras Cc: Stephane Eranian LKML-Reference: <1301535324-9735-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar --- tools/perf/builtin-record.c | 6 +++++- 1 files changed, 5 insertions(+), 1 deletions(-) diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index db6adec..17d1dcb 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -41,7 +41,7 @@ static u64 user_interval = ULLONG_MAX; static u64 default_interval = 0; static unsigned int page_size; -static unsigned int mmap_pages = 128; +static unsigned int mmap_pages = UINT_MAX; static unsigned int user_freq = UINT_MAX; static int freq = 1000; static int output; @@ -513,6 +513,10 @@ static int __cmd_record(int argc, const char **argv) if (have_tracepoints(&evsel_list->entries)) perf_header__set_feat(&session->header, HEADER_TRACE_INFO); + /* 512 kiB: default amount of unprivileged mlocked memory */ + if (mmap_pages == UINT_MAX) + mmap_pages = (512 * 1024) / page_size; + if (forks) { child_pid = fork(); if (child_pid < 0) { -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/