summaryrefslogtreecommitdiff
path: root/kernel/workqueue.c
diff options
context:
space:
mode:
authorLai Jiangshan <laijs@cn.fujitsu.com>2015-05-19 18:03:48 +0800
committerTejun Heo <tj@kernel.org>2015-05-19 17:37:00 -0400
commitd4d3e2579756e3a5f4fbf8eac211f0696e253bcd (patch)
treeb6d880e578cd07db0d60a8dee86c28d67abb446c /kernel/workqueue.c
parenta0111cf6710bd1b4145ef313d3f4772602af051b (diff)
downloadlinux-sh-d4d3e2579756e3a5f4fbf8eac211f0696e253bcd.tar.gz
workqueue: ensure attrs changes are properly synchronized
Current modification to attrs via sysfs is not fully synchronized. Process A (change cpumask) | Process B (change numa affinity) wq_cpumask_store() | wq_sysfs_prep_attrs() | | apply_workqueue_attrs() apply_workqueue_attrs() | It results that the Process B's operation is totally reverted without any notification, it is a buggy behavior. So this patch moves wq_sysfs_prep_attrs() into the protection under wq_pool_mutex to ensure attrs changes are properly synchronized. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'kernel/workqueue.c')
-rw-r--r--kernel/workqueue.c30
1 files changed, 21 insertions, 9 deletions
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 72c1adbf7632..80190755a3c4 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -4954,18 +4954,22 @@ static ssize_t wq_nice_store(struct device *dev, struct device_attribute *attr,
{
struct workqueue_struct *wq = dev_to_wq(dev);
struct workqueue_attrs *attrs;
- int ret;
+ int ret = -ENOMEM;
+
+ apply_wqattrs_lock();
attrs = wq_sysfs_prep_attrs(wq);
if (!attrs)
- return -ENOMEM;
+ goto out_unlock;
if (sscanf(buf, "%d", &attrs->nice) == 1 &&
attrs->nice >= MIN_NICE && attrs->nice <= MAX_NICE)
- ret = apply_workqueue_attrs(wq, attrs);
+ ret = apply_workqueue_attrs_locked(wq, attrs);
else
ret = -EINVAL;
+out_unlock:
+ apply_wqattrs_unlock();
free_workqueue_attrs(attrs);
return ret ?: count;
}
@@ -4989,16 +4993,20 @@ static ssize_t wq_cpumask_store(struct device *dev,
{
struct workqueue_struct *wq = dev_to_wq(dev);
struct workqueue_attrs *attrs;
- int ret;
+ int ret = -ENOMEM;
+
+ apply_wqattrs_lock();
attrs = wq_sysfs_prep_attrs(wq);
if (!attrs)
- return -ENOMEM;
+ goto out_unlock;
ret = cpumask_parse(buf, attrs->cpumask);
if (!ret)
- ret = apply_workqueue_attrs(wq, attrs);
+ ret = apply_workqueue_attrs_locked(wq, attrs);
+out_unlock:
+ apply_wqattrs_unlock();
free_workqueue_attrs(attrs);
return ret ?: count;
}
@@ -5022,18 +5030,22 @@ static ssize_t wq_numa_store(struct device *dev, struct device_attribute *attr,
{
struct workqueue_struct *wq = dev_to_wq(dev);
struct workqueue_attrs *attrs;
- int v, ret;
+ int v, ret = -ENOMEM;
+
+ apply_wqattrs_lock();
attrs = wq_sysfs_prep_attrs(wq);
if (!attrs)
- return -ENOMEM;
+ goto out_unlock;
ret = -EINVAL;
if (sscanf(buf, "%d", &v) == 1) {
attrs->no_numa = !v;
- ret = apply_workqueue_attrs(wq, attrs);
+ ret = apply_workqueue_attrs_locked(wq, attrs);
}
+out_unlock:
+ apply_wqattrs_unlock();
free_workqueue_attrs(attrs);
return ret ?: count;
}