linux-kernel - [PATCH 2/2] workqueue: update cpumask at CPU

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <5490631C.1010309@jp.fujitsu.com>
Date:	Wed, 17 Dec 2014 01:51:40 +0900
From:	Kamezawa Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
To:	Lai Jiangshan <laijs@...fujitsu.com>, Tejun Heo <tj@...nel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
CC:	"Ishimatsu, Yasuaki/石松 靖章" <isimatu.yasuaki@...fujitsu.com>,
	Tang Chen <tangchen@...fujitsu.com>,
	"guz.fnst@...fujitsu.com" <guz.fnst@...fujitsu.com>
Subject: [PATCH 2/2] workqueue: update cpumask at CPU_ONLINE if necessary

In some case, cpu's numa affinity will be changed in cpu_up().
It happens after a new node is onlined.
(in x86, online cpus are tied to onlined node at boot.
 so, if memory is added later, cpu mapping can be changed at cpu_up()

Although wq_numa_possible_cpumask at el. are maintained against
node hotplug, this case should be handled.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
---
 kernel/workqueue.c | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index f6ad05a..59d8be5 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -4618,6 +4618,27 @@ void workqueue_node_unregister(int node)
 	mutex_unlock(&wq_pool_mutex);
 }
 
+static void workqueue_may_update_numa_affinity(int cpu)
+{
+	int curnode = cpu_to_node(cpu);
+	int node;
+
+	if (likely(cpumask_test_cpu(cpu, wq_numa_possible_cpumask[curnode])))
+		return;
+
+	/* cpu<->node relationship is changed in cpu_up() */
+	for_each_node_state(node, N_POSSIBLE)
+		cpumask_clear_cpu(cpu, wq_numa_possible_cpumask[node]);
+
+	workqueue_update_cpu_numa_affinity(cpu, curnode);
+}
+#else
+
+static void workqueue_may_update_numa_affinity(int cpu)
+{
+	return;
+}
+
 #endif
 
 /*
@@ -4647,6 +4668,8 @@ static int workqueue_cpu_up_callback(struct notifier_block *nfb,
 	case CPU_ONLINE:
 		mutex_lock(&wq_pool_mutex);
 
+		workqueue_may_update_numa_affinity(cpu);
+
 		for_each_pool(pool, pi) {
 			mutex_lock(&pool->attach_mutex);
 
-- 
1.8.3.1



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/