Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758277AbaAGAJS (ORCPT ); Mon, 6 Jan 2014 19:09:18 -0500 Received: from mga09.intel.com ([134.134.136.24]:48538 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757665AbaAGAJQ (ORCPT ); Mon, 6 Jan 2014 19:09:16 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.95,615,1384329600"; d="scan'208";a="462584900" From: Andi Kleen To: akpm@linux-foundation.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andi Kleen Subject: [PATCH] Add a sysctl for numa_balancing v2 Date: Mon, 6 Jan 2014 16:08:46 -0800 Message-Id: <1389053326-29462-1-git-send-email-andi@firstfloor.org> X-Mailer: git-send-email 1.8.3.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andi Kleen [It turns out the documentation patch was already merged earlier. So just resending without documentation.] As discussed earlier, this adds a working sysctl to enable/disable automatic numa memory balancing at runtime. This allows to track down performance problems with this feature and is generally a good idea. This was possible earlier through debugfs, but only with special debugging options set. Also fix the boot message. v2: Remove documentation as the documentation for this sysctl was already merged earlier. Acked-by: Mel Gorman Signed-off-by: Andi Kleen --- include/linux/sched/sysctl.h | 4 ++++ kernel/sched/core.c | 24 +++++++++++++++++++++++- kernel/sysctl.c | 9 +++++++++ mm/mempolicy.c | 2 +- 4 files changed, 37 insertions(+), 2 deletions(-) diff --git a/include/linux/sched/sysctl.h b/include/linux/sched/sysctl.h index 41467f8..e134535 100644 --- a/include/linux/sched/sysctl.h +++ b/include/linux/sched/sysctl.h @@ -100,4 +100,8 @@ extern int sched_rt_handler(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos); +extern int sched_numa_balancing(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, + loff_t *ppos); + #endif /* _SCHED_SYSCTL_H */ diff --git a/kernel/sched/core.c b/kernel/sched/core.c index a88f4a4..4dc22da 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1763,7 +1763,29 @@ void set_numabalancing_state(bool enabled) numabalancing_enabled = enabled; } #endif /* CONFIG_SCHED_DEBUG */ -#endif /* CONFIG_NUMA_BALANCING */ + +#ifdef CONFIG_PROC_SYSCTL +int sched_numa_balancing(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, loff_t *ppos) +{ + struct ctl_table t; + int err; + int state = numabalancing_enabled; + + if (write && !capable(CAP_SYS_ADMIN)) + return -EPERM; + + t = *table; + t.data = &state; + err = proc_dointvec_minmax(&t, write, buffer, lenp, ppos); + if (err < 0) + return err; + if (write) + set_numabalancing_state(state); + return err; +} +#endif +#endif /* * fork()/clone()-time setup: diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 34a6047..9e0e790 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -398,6 +398,15 @@ static struct ctl_table kern_table[] = { .mode = 0644, .proc_handler = proc_dointvec, }, + { + .procname = "numa_balancing", + .data = NULL, /* filled in by handler */ + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = sched_numa_balancing, + .extra1 = &zero, + .extra2 = &one, + }, #endif /* CONFIG_NUMA_BALANCING */ #endif /* CONFIG_SCHED_DEBUG */ { diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 0cd2c4d..947293e 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -2668,7 +2668,7 @@ static void __init check_numabalancing_enable(void) if (nr_node_ids > 1 && !numabalancing_override) { printk(KERN_INFO "Enabling automatic NUMA balancing. " - "Configure with numa_balancing= or sysctl"); + "Configure with numa_balancing= or the kernel.numa_balancing sysctl"); set_numabalancing_state(numabalancing_default); } } -- 1.8.3.1 -- 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/