trusty: add a toggle for using high prio WQ

Bug: 229350721
Test: UDFPS with stress
Signed-off-by: Wei Wang <wvw@google.com>
(cherry picked from commit 229137adb4627cb9341b7148bee797fbddad2e80)
Change-Id: I241a9a6ecd840577601dae7886fb212a2d46d71d
(cherry picked from commit bc10c2f6eb1a3f51a814c7acd84ee07cba63e144)
Signed-off-by: Will McVicker <willmcvicker@google.com>

2 files changed, 51 insertions, 5 deletions

diff --git a/drivers/trusty/trusty-virtio.c b/drivers/trusty/trusty-virtio.c
index fea59cd..30111c4 100644
--- a/drivers/trusty/trusty-virtio.c
+++ b/drivers/trusty/trusty-virtio.c
@@ -31,7 +31,8 @@
 #define  RSC_DESCR_VER  1
 
 struct trusty_vdev;
-
+static bool use_high_wq;
+module_param(use_high_wq, bool, 0660);
 struct trusty_ctx {
 	struct device		*dev;
 	void			*shared_va;
@@ -45,6 +46,8 @@ struct trusty_ctx {
 	struct mutex		mlock; /* protects vdev_list */
 	struct workqueue_struct	*kick_wq;
 	struct workqueue_struct	*check_wq;
+	struct workqueue_struct	*kick_wq_high;
+	struct workqueue_struct	*check_wq_high;
 };
 
 struct trusty_vring {
@@ -99,8 +102,10 @@ static int trusty_call_notify(struct notifier_block *nb,
 		return NOTIFY_DONE;
 
 	tctx = container_of(nb, struct trusty_ctx, call_notifier);
-	queue_work(tctx->check_wq, &tctx->check_vqs);
-
+	if (use_high_wq)
+		queue_work(tctx->check_wq_high, &tctx->check_vqs);
+	else
+		queue_work(tctx->check_wq, &tctx->check_vqs);
 	return NOTIFY_OK;
 }
 
@@ -148,7 +153,10 @@ static bool trusty_virtio_notify(struct virtqueue *vq)
 
 	if (api_ver < TRUSTY_API_VERSION_SMP_NOP) {
 		atomic_set(&tvr->needs_kick, 1);
-		queue_work(tctx->kick_wq, &tctx->kick_vqs);
+		if (use_high_wq)
+			queue_work(tctx->kick_wq_high, &tctx->kick_vqs);
+		else
+			queue_work(tctx->kick_wq, &tctx->kick_vqs);
 	} else {
 		trusty_enqueue_nop(tctx->dev->parent, &tvr->kick_nop);
 	}
@@ -751,6 +759,21 @@ static int trusty_virtio_probe(struct platform_device *pdev)
 		goto err_create_kick_wq;
 	}
 
+	tctx->check_wq_high = alloc_workqueue("trusty-check-wq-high", WQ_UNBOUND | WQ_HIGHPRI, 0);
+	if (!tctx->check_wq_high) {
+		ret = -ENODEV;
+		dev_err(&pdev->dev, "Failed create trusty-check-wq-high\n");
+		goto err_create_check_wq_high;
+	}
+
+	tctx->kick_wq_high = alloc_workqueue("trusty-kick-wq-high",
+					WQ_UNBOUND | WQ_CPU_INTENSIVE | WQ_HIGHPRI, 0);
+	if (!tctx->kick_wq_high) {
+		ret = -ENODEV;
+		dev_err(&pdev->dev, "Failed create trusty-kick-wq-high\n");
+		goto err_create_kick_wq_high;
+	}
+
 	ret = trusty_virtio_add_devices(tctx);
 	if (ret) {
 		dev_err(&pdev->dev, "Failed to add virtio devices\n");
@@ -761,6 +784,10 @@ static int trusty_virtio_probe(struct platform_device *pdev)
 	return 0;
 
 err_add_devices:
+	destroy_workqueue(tctx->kick_wq_high);
+err_create_kick_wq_high:
+	destroy_workqueue(tctx->check_wq_high);
+err_create_check_wq_high:
 	destroy_workqueue(tctx->kick_wq);
 err_create_kick_wq:
 	destroy_workqueue(tctx->check_wq);
@@ -786,6 +813,8 @@ static int trusty_virtio_remove(struct platform_device *pdev)
 	/* destroy workqueues */
 	destroy_workqueue(tctx->kick_wq);
 	destroy_workqueue(tctx->check_wq);
+	destroy_workqueue(tctx->kick_wq_high);
+	destroy_workqueue(tctx->check_wq_high);
 
 	/* notify remote that shared area goes away */
 	trusty_virtio_stop(tctx, tctx->shared_id, tctx->shared_sz);
diff --git a/drivers/trusty/trusty.c b/drivers/trusty/trusty.c
index 265eab5..3cfe7e2 100644
--- a/drivers/trusty/trusty.c
+++ b/drivers/trusty/trusty.c
@@ -24,6 +24,9 @@
 struct trusty_state;
 static struct platform_driver trusty_driver;
 
+static bool use_high_wq;
+module_param(use_high_wq, bool, 0660);
+
 struct trusty_work {
 	struct trusty_state *ts;
 	struct work_struct work;
@@ -38,6 +41,7 @@ struct trusty_state {
 	bool trusty_panicked;
 	struct device *dev;
 	struct workqueue_struct *nop_wq;
+	struct workqueue_struct *nop_wq_high;
 	struct trusty_work __percpu *nop_works;
 	struct list_head nop_queue;
 	spinlock_t nop_lock; /* protects nop_queue */
@@ -799,7 +803,10 @@ void trusty_enqueue_nop(struct device *dev, struct trusty_nop *nop)
 			list_add_tail(&nop->node, &s->nop_queue);
 		spin_unlock_irqrestore(&s->nop_lock, flags);
 	}
-	queue_work(s->nop_wq, &tw->work);
+	if (use_high_wq)
+		queue_work(s->nop_wq_high, &tw->work);
+	else
+		queue_work(s->nop_wq, &tw->work);
 	preempt_enable();
 }
 EXPORT_SYMBOL(trusty_enqueue_nop);
@@ -873,6 +880,13 @@ static int trusty_probe(struct platform_device *pdev)
 		goto err_create_nop_wq;
 	}
 
+	s->nop_wq_high = alloc_workqueue("trusty-nop-wq-high", WQ_HIGHPRI | WQ_CPU_INTENSIVE, 0);
+	if (!s->nop_wq_high) {
+		ret = -ENODEV;
+		dev_err(&pdev->dev, "Failed create trusty-nop-wq-high\n");
+		goto err_create_nop_wq_high;
+	}
+
 	s->nop_works = alloc_percpu(struct trusty_work);
 	if (!s->nop_works) {
 		ret = -ENOMEM;
@@ -908,6 +922,8 @@ err_add_children:
 	}
 	free_percpu(s->nop_works);
 err_alloc_works:
+	destroy_workqueue(s->nop_wq_high);
+err_create_nop_wq_high:
 	destroy_workqueue(s->nop_wq);
 err_create_nop_wq:
 	trusty_free_msg_buf(s, &pdev->dev);
@@ -937,6 +953,7 @@ static int trusty_remove(struct platform_device *pdev)
 	}
 	free_percpu(s->nop_works);
 	destroy_workqueue(s->nop_wq);
+	destroy_workqueue(s->nop_wq_high);
 
 	mutex_destroy(&s->share_memory_msg_lock);
 	mutex_destroy(&s->smc_lock);