From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933332Ab2CZSM2 (ORCPT ); Mon, 26 Mar 2012 14:12:28 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44898 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933259Ab2CZSMY (ORCPT ); Mon, 26 Mar 2012 14:12:24 -0400 From: Andrea Arcangeli To: linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: Hillf Danton , Dan Smith , Peter Zijlstra , Linus Torvalds , Andrew Morton , Thomas Gleixner , Ingo Molnar , Paul Turner , Suresh Siddha , Mike Galbraith , "Paul E. McKenney" , Lai Jiangshan , Bharata B Rao , Lee Schermerhorn , Rik van Riel , Johannes Weiner Subject: [PATCH 07/39] autonuma: introduce kthread_bind_node() Date: Mon, 26 Mar 2012 19:45:54 +0200 Message-Id: <1332783986-24195-8-git-send-email-aarcange@redhat.com> In-Reply-To: <1332783986-24195-1-git-send-email-aarcange@redhat.com> References: <1332783986-24195-1-git-send-email-aarcange@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This function makes it easy to bind the per-node knuma_migrated threads to their respective NUMA nodes. Those threads take memory from the other nodes (in round robin with a incoming queue for each remote node) and they move that memory to their local node. Signed-off-by: Andrea Arcangeli --- include/linux/kthread.h | 1 + kernel/kthread.c | 23 +++++++++++++++++++++++ 2 files changed, 24 insertions(+), 0 deletions(-) diff --git a/include/linux/kthread.h b/include/linux/kthread.h index 0714b24..e733f97 100644 --- a/include/linux/kthread.h +++ b/include/linux/kthread.h @@ -33,6 +33,7 @@ struct task_struct *kthread_create_on_node(int (*threadfn)(void *data), }) void kthread_bind(struct task_struct *k, unsigned int cpu); +void kthread_bind_node(struct task_struct *p, int nid); int kthread_stop(struct task_struct *k); int kthread_should_stop(void); bool kthread_freezable_should_stop(bool *was_frozen); diff --git a/kernel/kthread.c b/kernel/kthread.c index 3d3de63..48b36f9 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -234,6 +234,29 @@ void kthread_bind(struct task_struct *p, unsigned int cpu) EXPORT_SYMBOL(kthread_bind); /** + * kthread_bind_node - bind a just-created kthread to the CPUs of a node. + * @p: thread created by kthread_create(). + * @nid: node (might not be online, must be possible) for @k to run on. + * + * Description: This function is equivalent to set_cpus_allowed(), + * except that @nid doesn't need to be online, and the thread must be + * stopped (i.e., just returned from kthread_create()). + */ +void kthread_bind_node(struct task_struct *p, int nid) +{ + /* Must have done schedule() in kthread() before we set_task_cpu */ + if (!wait_task_inactive(p, TASK_UNINTERRUPTIBLE)) { + WARN_ON(1); + return; + } + + /* It's safe because the task is inactive. */ + do_set_cpus_allowed(p, cpumask_of_node(nid)); + p->flags |= PF_THREAD_BOUND; +} +EXPORT_SYMBOL(kthread_bind_node); + +/** * kthread_stop - stop a thread created by kthread_create(). * @k: thread created by kthread_create(). *