From patchwork Tue Oct 16 17:56:26 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marcelo Tosatti X-Patchwork-Id: 1602101 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id 3C0B7DFFED for ; Tue, 16 Oct 2012 18:00:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755675Ab2JPSAi (ORCPT ); Tue, 16 Oct 2012 14:00:38 -0400 Received: from mx1.redhat.com ([209.132.183.28]:1104 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755286Ab2JPSAi (ORCPT ); Tue, 16 Oct 2012 14:00:38 -0400 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id q9GHxmCq002918 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Tue, 16 Oct 2012 13:59:48 -0400 Received: from amt.cnet (vpn-200-116.tlv.redhat.com [10.35.200.116]) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id q9GHxjb6018234; Tue, 16 Oct 2012 13:59:47 -0400 Received: from amt.cnet (amt.cnet [127.0.0.1]) by amt.cnet (Postfix) with ESMTP id 6DFB068A2E8; Tue, 16 Oct 2012 14:59:06 -0300 (BRT) Received: (from marcelo@localhost) by amt.cnet (8.14.5/8.14.5/Submit) id q9GHx3fK008619; Tue, 16 Oct 2012 14:59:03 -0300 Message-Id: <20121016180137.604804511@redhat.com> User-Agent: quilt/0.47-1 Date: Tue, 16 Oct 2012 14:56:26 -0300 From: Marcelo Tosatti To: kvm@vger.kernel.org Cc: johnstul@us.ibm.com, jeremy@goop.org, Marcelo Tosatti Subject: [patch 07/15] sched: add notifier for cross-cpu migrations References: <20121016175619.194848607@redhat.com> Content-Disposition: inline; filename=06-add-task-migration-notifier X-Scanned-By: MIMEDefang 2.68 on 10.5.11.24 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Originally from Jeremy Fitzhardinge. Signed-off-by: Marcelo Tosatti --- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Index: vsyscall/include/linux/sched.h =================================================================== --- vsyscall.orig/include/linux/sched.h +++ vsyscall/include/linux/sched.h @@ -107,6 +107,14 @@ extern unsigned long this_cpu_load(void) extern void calc_global_load(unsigned long ticks); extern void update_cpu_load_nohz(void); +/* Notifier for when a task gets migrated to a new CPU */ +struct task_migration_notifier { + struct task_struct *task; + int from_cpu; + int to_cpu; +}; +extern void register_task_migration_notifier(struct notifier_block *n); + extern unsigned long get_parent_ip(unsigned long addr); struct seq_file; Index: vsyscall/kernel/sched/core.c =================================================================== --- vsyscall.orig/kernel/sched/core.c +++ vsyscall/kernel/sched/core.c @@ -922,6 +922,13 @@ void check_preempt_curr(struct rq *rq, s rq->skip_clock_update = 1; } +static ATOMIC_NOTIFIER_HEAD(task_migration_notifier); + +void register_task_migration_notifier(struct notifier_block *n) +{ + atomic_notifier_chain_register(&task_migration_notifier, n); +} + #ifdef CONFIG_SMP void set_task_cpu(struct task_struct *p, unsigned int new_cpu) { @@ -952,8 +959,16 @@ void set_task_cpu(struct task_struct *p, trace_sched_migrate_task(p, new_cpu); if (task_cpu(p) != new_cpu) { + struct task_migration_notifier tmn; + p->se.nr_migrations++; perf_sw_event(PERF_COUNT_SW_CPU_MIGRATIONS, 1, NULL, 0); + + tmn.task = p; + tmn.from_cpu = task_cpu(p); + tmn.to_cpu = new_cpu; + + atomic_notifier_call_chain(&task_migration_notifier, 0, &tmn); } __set_task_cpu(p, new_cpu);