From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757517AbbCCXA2 (ORCPT ); Tue, 3 Mar 2015 18:00:28 -0500 Received: from shelob.surriel.com ([74.92.59.67]:52028 "EHLO shelob.surriel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756742AbbCCXAZ (ORCPT ); Tue, 3 Mar 2015 18:00:25 -0500 From: riel@redhat.com To: tj@kernel.org Cc: linux-kernel@vger.kernel.org Subject: [PATCH 3/4] cpusets,isolcpus: add file to show isolated cpus in cpuset Date: Tue, 3 Mar 2015 18:00:22 -0500 Message-Id: <1425423623-31316-4-git-send-email-riel@redhat.com> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1425423623-31316-1-git-send-email-riel@redhat.com> References: <1425423623-31316-1-git-send-email-riel@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rik van Riel The previous patch makes it so the code skips over isolcpus when building scheduler load balancing domains. This makes it hard to see for a user which of the CPUs in a cpuset are participating in load balancing, and which ones are isolated cpus. Add a cpuset.isolcpus file with info on which cpus in a cpuset are isolated CPUs. This file is read-only for now. In the future we could extend things so isolcpus can be changed at run time, for the root (system wide) cpuset only. Acked-by: David Rientjes Cc: Peter Zijlstra Cc: Clark Williams Cc: Li Zefan Cc: Ingo Molnar Cc: Luiz Capitulino Cc: David Rientjes Cc: Mike Galbraith Cc: cgroups@vger.kernel.org Signed-off-by: Rik van Riel --- kernel/cpuset.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/kernel/cpuset.c b/kernel/cpuset.c index b544e5229d99..5462e1ca90bd 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -1563,6 +1563,7 @@ typedef enum { FILE_MEMORY_PRESSURE, FILE_SPREAD_PAGE, FILE_SPREAD_SLAB, + FILE_ISOLCPUS, } cpuset_filetype_t; static int cpuset_write_u64(struct cgroup_subsys_state *css, struct cftype *cft, @@ -1704,6 +1705,16 @@ static ssize_t cpuset_write_resmask(struct kernfs_open_file *of, return retval ?: nbytes; } +/* protected by the lock in cpuset_common_seq_show */ +static cpumask_var_t print_isolated_cpus; + +static void cpuset_seq_print_isolcpus(struct seq_file *sf, struct cpuset *cs) +{ + cpumask_and(print_isolated_cpus, cs->cpus_allowed, cpu_isolated_map); + + seq_printf(sf, "%*pbl\n", cpumask_pr_args(print_isolated_cpus)); +} + /* * These ascii lists should be read in a single call, by using a user * buffer large enough to hold the entire map. If read in smaller @@ -1733,6 +1744,9 @@ static int cpuset_common_seq_show(struct seq_file *sf, void *v) case FILE_EFFECTIVE_MEMLIST: seq_printf(sf, "%*pbl\n", nodemask_pr_args(&cs->effective_mems)); break; + case FILE_ISOLCPUS: + cpuset_seq_print_isolcpus(sf, cs); + break; default: ret = -EINVAL; } @@ -1893,6 +1907,12 @@ static struct cftype files[] = { .private = FILE_MEMORY_PRESSURE_ENABLED, }, + { + .name = "isolcpus", + .seq_show = cpuset_common_seq_show, + .private = FILE_ISOLCPUS, + }, + { } /* terminate */ }; @@ -2070,6 +2090,8 @@ int __init cpuset_init(void) BUG(); if (!alloc_cpumask_var(&top_cpuset.effective_cpus, GFP_KERNEL)) BUG(); + if (!alloc_cpumask_var(&print_isolated_cpus, GFP_KERNEL)) + BUG(); cpumask_setall(top_cpuset.cpus_allowed); nodes_setall(top_cpuset.mems_allowed); -- 2.1.0