[RFC PATCH V5 4/5] workqueue: convert ->nice to ->sched_attr

[Wen Yang]

The possibility of specifying more than just a nice
for the wq may be useful for a wide variety of applications.

Signed-off-by: Wen Yang <wen.yang99@xxxxxxxxxx>
Signed-off-by: Jiang Biao <jiang.biao2@xxxxxxxxxx>
Signed-off-by: Tan Hu <tan.hu@xxxxxxxxxx>
Suggested-by: Tejun Heo <tj@xxxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: Lai Jiangshan <jiangshanlai@xxxxxxxxx>
Cc: kernel test robot <xiaolong.ye@xxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
 include/linux/workqueue.h |  5 +++--
 kernel/workqueue.c        | 27 +++++++++++++++------------
 2 files changed, 18 insertions(+), 14 deletions(-)

diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
index 4a54ef9..d9d0f36 100644
--- a/include/linux/workqueue.h
+++ b/include/linux/workqueue.h
@@ -13,6 +13,7 @@
 #include <linux/threads.h>
 #include <linux/atomic.h>
 #include <linux/cpumask.h>
+#include <uapi/linux/sched/types.h>
 
 struct workqueue_struct;
 
@@ -127,9 +128,9 @@ struct delayed_work {
  */
 struct workqueue_attrs {
 	/**
-	 * @nice: nice level
+	 * @sched_attr: kworker's scheduling parameters
 	 */
-	int nice;
+	struct sched_attr sched_attr;
 
 	/**
 	 * @cpumask: allowed CPUs
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index df22ecb..fca0e30 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -1772,7 +1772,7 @@ static struct worker *create_worker(struct worker_pool *pool)
 
 	if (pool->cpu >= 0)
 		snprintf(id_buf, sizeof(id_buf), "%d:%d%s", pool->cpu, id,
-			 pool->attrs->nice < 0  ? "H" : "");
+			 pool->attrs->sched_attr.sched_nice < 0  ? "H" : "");
 	else
 		snprintf(id_buf, sizeof(id_buf), "u%d:%d", pool->id, id);
 
@@ -1781,7 +1781,7 @@ static struct worker *create_worker(struct worker_pool *pool)
 	if (IS_ERR(worker->task))
 		goto fail;
 
-	set_user_nice(worker->task, pool->attrs->nice);
+	set_user_nice(worker->task, pool->attrs->sched_attr.sched_nice);
 	kthread_bind_mask(worker->task, pool->attrs->cpumask);
 
 	/* successful, attach the worker to the pool */
@@ -3169,7 +3169,7 @@ struct workqueue_attrs *alloc_workqueue_attrs(gfp_t gfp_mask)
 static void copy_workqueue_attrs(struct workqueue_attrs *to,
 				 const struct workqueue_attrs *from)
 {
-	to->nice = from->nice;
+	to->sched_attr.sched_nice = from->sched_attr.sched_nice;
 	cpumask_copy(to->cpumask, from->cpumask);
 	/*
 	 * Unlike hash and equality test, this function doesn't ignore
@@ -3184,7 +3184,7 @@ static u32 wqattrs_hash(const struct workqueue_attrs *attrs)
 {
 	u32 hash = 0;
 
-	hash = jhash_1word(attrs->nice, hash);
+	hash = jhash_1word(attrs->sched_attr.sched_nice, hash);
 	hash = jhash(cpumask_bits(attrs->cpumask),
 		     BITS_TO_LONGS(nr_cpumask_bits) * sizeof(long), hash);
 	return hash;
@@ -3194,7 +3194,7 @@ static u32 wqattrs_hash(const struct workqueue_attrs *attrs)
 static bool wqattrs_equal(const struct workqueue_attrs *a,
 			  const struct workqueue_attrs *b)
 {
-	if (a->nice != b->nice)
+	if (a->sched_attr.sched_nice != b->sched_attr.sched_nice)
 		return false;
 	if (!cpumask_equal(a->cpumask, b->cpumask))
 		return false;
@@ -4336,7 +4336,8 @@ static void pr_cont_pool_info(struct worker_pool *pool)
 	pr_cont(" cpus=%*pbl", nr_cpumask_bits, pool->attrs->cpumask);
 	if (pool->node != NUMA_NO_NODE)
 		pr_cont(" node=%d", pool->node);
-	pr_cont(" flags=0x%x nice=%d", pool->flags, pool->attrs->nice);
+	pr_cont(" flags=0x%x nice=%d", pool->flags,
+			pool->attrs->sched_attr.sched_nice);
 }
 
 static void pr_cont_work(bool comma, struct work_struct *work)
@@ -5074,7 +5075,8 @@ static ssize_t wq_nice_show(struct device *dev, struct device_attribute *attr,
 	int written;
 
 	mutex_lock(&wq->mutex);
-	written = scnprintf(buf, PAGE_SIZE, "%d\n", wq->attrs->nice);
+	written = scnprintf(buf, PAGE_SIZE, "%d\n",
+			wq->attrs->sched_attr.sched_nice);
 	mutex_unlock(&wq->mutex);
 
 	return written;
@@ -5108,8 +5110,9 @@ static ssize_t wq_nice_store(struct device *dev, struct device_attribute *attr,
 	if (!attrs)
 		goto out_unlock;
 
-	if (sscanf(buf, "%d", &attrs->nice) == 1 &&
-	    attrs->nice >= MIN_NICE && attrs->nice <= MAX_NICE)
+	if (sscanf(buf, "%d", &attrs->sched_attr.sched_nice) == 1 &&
+	    attrs->sched_attr.sched_nice >= MIN_NICE &&
+	    attrs->sched_attr.sched_nice <= MAX_NICE)
 		ret = apply_workqueue_attrs_locked(wq, attrs);
 	else
 		ret = -EINVAL;
@@ -5573,7 +5576,7 @@ int __init workqueue_init_early(void)
 			BUG_ON(init_worker_pool(pool));
 			pool->cpu = cpu;
 			cpumask_copy(pool->attrs->cpumask, cpumask_of(cpu));
-			pool->attrs->nice = std_nice[i++];
+			pool->attrs->sched_attr.sched_nice = std_nice[i++];
 			pool->node = cpu_to_node(cpu);
 
 			/* alloc pool ID */
@@ -5588,7 +5591,7 @@ int __init workqueue_init_early(void)
 		struct workqueue_attrs *attrs;
 
 		BUG_ON(!(attrs = alloc_workqueue_attrs(GFP_KERNEL)));
-		attrs->nice = std_nice[i];
+		attrs->sched_attr.sched_nice = std_nice[i];
 		unbound_std_wq_attrs[i] = attrs;
 
 		/*
@@ -5597,7 +5600,7 @@ int __init workqueue_init_early(void)
 		 * Turn off NUMA so that dfl_pwq is used for all nodes.
 		 */
 		BUG_ON(!(attrs = alloc_workqueue_attrs(GFP_KERNEL)));
-		attrs->nice = std_nice[i];
+		attrs->sched_attr.sched_nice = std_nice[i];
 		attrs->no_numa = true;
 		ordered_wq_attrs[i] = attrs;
 	}
-- 
1.8.3.1