[PATCH v3 0/8] tools/vhost: Reset virtqueue on tests

[PATCH v3 0/8] tools/vhost: Reset virtqueue on tests

[Eugenio Pérez]

This series add tests used to validate the "vhost: Reset batched
descriptors on SET_VRING_BASE call" series, with a few minor updates of
them.

They are based on the tests sent back them, the ones that were not
included (reasons in that thread). This series changes:

* Delete need to export the ugly function in virtio_ring, now all the
code is added in tools/virtio (except the one line fix).
* Add forgotten uses of vhost_vq_set_backend. Fix bad usage order in
vhost_test_set_backend.
* Drop random reset, not really needed.
* Minor changes.

The first patch of this patchset ("vhost: Not cleaning batched descs in
VHOST_SET_VRING_BASE ioctl") should be squashed with ("vhost: batching
fetches") (currenlty, commit e7539c20a4a60b3a1bda3e7218c0d2a20669f357
in mst repository vhost branch).

Thanks!

Changes from v2:
* Squashed commits with fixes.
* Back to plain vring_*

Changes from v1:
* Different base, since branch was force-pushed.
* Using new vring_legacy_*, as base uses them now.

This serie is meant to be applied on top of
801f9bae9cf35b3192c3959d81a717e7985c64ed in
git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git.

Eugenio Pérez (8):
  vhost: Not cleaning batched descs in VHOST_SET_VRING_BASE ioctl
  tools/virtio: Add --batch option
  tools/virtio: Add --batch=random option
  tools/virtio: Add --reset
  tools/virtio: Use __vring_new_virtqueue in virtio_test.c
  tools/virtio: Extract virtqueue initialization in vq_reset
  tools/virtio: Reset index in virtio_test --reset.
  tools/virtio: Use tools/include/list.h instead of stubs

 drivers/vhost/test.c        |  57 +++++++++++++++
 drivers/vhost/test.h        |   1 +
 drivers/vhost/vhost.c       |   1 -
 tools/virtio/linux/kernel.h |   7 +-
 tools/virtio/linux/virtio.h |   5 +-
 tools/virtio/virtio_test.c  | 139 ++++++++++++++++++++++++++++++------
 tools/virtio/vringh_test.c  |   2 +
 7 files changed, 182 insertions(+), 30 deletions(-)

-- 
2.18.1

[PATCH v3 1/8] vhost: Not cleaning batched descs in VHOST_SET_VRING_BASE ioctl

[Eugenio Pérez]

They are cleaned in vhost_vq_set_backend, which can be called with an
active backend. To set and remove backends already clean batched
descriptors, so to do it here is completely redundant.

Fixes: ("e7539c20a4a6 vhost: batching fetches")

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
---
 drivers/vhost/vhost.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 0395229486a9..882d0df57e24 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -1579,7 +1579,6 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg
 		vq->last_avail_idx = s.num;
 		/* Forget the cached index value. */
 		vq->avail_idx = vq->last_avail_idx;
-		vq->ndescs = vq->first_desc = 0;
 		break;
 	case VHOST_GET_VRING_BASE:
 		s.index = idx;
-- 
2.18.1

[PATCH v3 2/8] tools/virtio: Add --batch option

[Eugenio Pérez]

This allow to test vhost having >1 buffers in flight

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Link: https://lore.kernel.org/r/20200401183118.8334-5-eperezma@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 tools/virtio/virtio_test.c | 47 ++++++++++++++++++++++++++++++--------
 1 file changed, 37 insertions(+), 10 deletions(-)

diff --git a/tools/virtio/virtio_test.c b/tools/virtio/virtio_test.c
index b427def67e7e..c30de9088f3c 100644
--- a/tools/virtio/virtio_test.c
+++ b/tools/virtio/virtio_test.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 #define _GNU_SOURCE
 #include <getopt.h>
+#include <limits.h>
 #include <string.h>
 #include <poll.h>
 #include <sys/eventfd.h>
@@ -152,11 +153,11 @@ static void wait_for_interrupt(struct vdev_info *dev)
 }
 
 static void run_test(struct vdev_info *dev, struct vq_info *vq,
-		     bool delayed, int bufs)
+		     bool delayed, int batch, int bufs)
 {
 	struct scatterlist sl;
 	long started = 0, completed = 0;
-	long completed_before;
+	long completed_before, started_before;
 	int r, test = 1;
 	unsigned len;
 	long long spurious = 0;
@@ -165,28 +166,42 @@ static void run_test(struct vdev_info *dev, struct vq_info *vq,
 	for (;;) {
 		virtqueue_disable_cb(vq->vq);
 		completed_before = completed;
+		started_before = started;
 		do {
-			if (started < bufs) {
+			while (started < bufs &&
+			       (started - completed) < batch) {
 				sg_init_one(&sl, dev->buf, dev->buf_size);
 				r = virtqueue_add_outbuf(vq->vq, &sl, 1,
 							 dev->buf + started,
 							 GFP_ATOMIC);
-				if (likely(r == 0)) {
-					++started;
-					if (unlikely(!virtqueue_kick(vq->vq)))
+				if (unlikely(r != 0)) {
+					if (r == -ENOSPC &&
+					    started > started_before)
+						r = 0;
+					else
 						r = -1;
+					break;
 				}
-			} else
+
+				++started;
+
+				if (unlikely(!virtqueue_kick(vq->vq))) {
+					r = -1;
+					break;
+				}
+			}
+
+			if (started >= bufs)
 				r = -1;
 
 			/* Flush out completed bufs if any */
-			if (virtqueue_get_buf(vq->vq, &len)) {
+			while (virtqueue_get_buf(vq->vq, &len)) {
 				++completed;
 				r = 0;
 			}
 
 		} while (r == 0);
-		if (completed == completed_before)
+		if (completed == completed_before && started == started_before)
 			++spurious;
 		assert(completed <= bufs);
 		assert(started <= bufs);
@@ -244,6 +259,11 @@ const struct option longopts[] = {
 		.name = "no-delayed-interrupt",
 		.val = 'd',
 	},
+	{
+		.name = "batch",
+		.val = 'b',
+		.has_arg = required_argument,
+	},
 	{
 	}
 };
@@ -255,6 +275,7 @@ static void help(void)
 		" [--no-event-idx]"
 		" [--no-virtio-1]"
 		" [--delayed-interrupt]"
+		" [--batch=N]"
 		"\n");
 }
 
@@ -263,6 +284,7 @@ int main(int argc, char **argv)
 	struct vdev_info dev;
 	unsigned long long features = (1ULL << VIRTIO_RING_F_INDIRECT_DESC) |
 		(1ULL << VIRTIO_RING_F_EVENT_IDX) | (1ULL << VIRTIO_F_VERSION_1);
+	long batch = 1;
 	int o;
 	bool delayed = false;
 
@@ -289,6 +311,11 @@ int main(int argc, char **argv)
 		case 'D':
 			delayed = true;
 			break;
+		case 'b':
+			batch = strtol(optarg, NULL, 10);
+			assert(batch > 0);
+			assert(batch < (long)INT_MAX + 1);
+			break;
 		default:
 			assert(0);
 			break;
@@ -298,6 +325,6 @@ int main(int argc, char **argv)
 done:
 	vdev_info_init(&dev, features);
 	vq_info_add(&dev, 256);
-	run_test(&dev, &dev.vqs[0], delayed, 0x100000);
+	run_test(&dev, &dev.vqs[0], delayed, batch, 0x100000);
 	return 0;
 }
-- 
2.18.1

[PATCH v3 3/8] tools/virtio: Add --batch=random option

[Eugenio Pérez]

So we can test with non-deterministic batches in flight.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
---
 tools/virtio/virtio_test.c | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/tools/virtio/virtio_test.c b/tools/virtio/virtio_test.c
index c30de9088f3c..4a2b9d11f287 100644
--- a/tools/virtio/virtio_test.c
+++ b/tools/virtio/virtio_test.c
@@ -19,6 +19,8 @@
 #include <linux/virtio_ring.h>
 #include "../../drivers/vhost/test.h"
 
+#define RANDOM_BATCH -1
+
 /* Unused */
 void *__kmalloc_fake, *__kfree_ignore_start, *__kfree_ignore_end;
 
@@ -161,6 +163,7 @@ static void run_test(struct vdev_info *dev, struct vq_info *vq,
 	int r, test = 1;
 	unsigned len;
 	long long spurious = 0;
+	const bool random_batch = batch == RANDOM_BATCH;
 	r = ioctl(dev->control, VHOST_TEST_RUN, &test);
 	assert(r >= 0);
 	for (;;) {
@@ -168,6 +171,9 @@ static void run_test(struct vdev_info *dev, struct vq_info *vq,
 		completed_before = completed;
 		started_before = started;
 		do {
+			if (random_batch)
+				batch = (random() % vq->vring.num) + 1;
+
 			while (started < bufs &&
 			       (started - completed) < batch) {
 				sg_init_one(&sl, dev->buf, dev->buf_size);
@@ -275,7 +281,7 @@ static void help(void)
 		" [--no-event-idx]"
 		" [--no-virtio-1]"
 		" [--delayed-interrupt]"
-		" [--batch=N]"
+		" [--batch=random/N]"
 		"\n");
 }
 
@@ -312,9 +318,13 @@ int main(int argc, char **argv)
 			delayed = true;
 			break;
 		case 'b':
-			batch = strtol(optarg, NULL, 10);
-			assert(batch > 0);
-			assert(batch < (long)INT_MAX + 1);
+			if (0 == strcmp(optarg, "random")) {
+				batch = RANDOM_BATCH;
+			} else {
+				batch = strtol(optarg, NULL, 10);
+				assert(batch > 0);
+				assert(batch < (long)INT_MAX + 1);
+			}
 			break;
 		default:
 			assert(0);
-- 
2.18.1

[PATCH v3 4/8] tools/virtio: Add --reset

[Eugenio Pérez]

Currently, it only removes and add backend, but it will reset vq
position in future commits.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
---
 drivers/vhost/test.c       | 57 ++++++++++++++++++++++++++++++++++++++
 drivers/vhost/test.h       |  1 +
 tools/virtio/virtio_test.c | 41 ++++++++++++++++++++++++---
 3 files changed, 95 insertions(+), 4 deletions(-)

diff --git a/drivers/vhost/test.c b/drivers/vhost/test.c
index 02806d6f84ef..6aed0cab8b17 100644
--- a/drivers/vhost/test.c
+++ b/drivers/vhost/test.c
@@ -263,9 +263,62 @@ static int vhost_test_set_features(struct vhost_test *n, u64 features)
 	return 0;
 }
 
+static long vhost_test_set_backend(struct vhost_test *n, unsigned index, int fd)
+{
+	static void *backend;
+
+	const bool enable = fd != -1;
+	struct vhost_virtqueue *vq;
+	int r;
+
+	mutex_lock(&n->dev.mutex);
+	r = vhost_dev_check_owner(&n->dev);
+	if (r)
+		goto err;
+
+	if (index >= VHOST_TEST_VQ_MAX) {
+		r = -ENOBUFS;
+		goto err;
+	}
+	vq = &n->vqs[index];
+	mutex_lock(&vq->mutex);
+
+	/* Verify that ring has been setup correctly. */
+	if (!vhost_vq_access_ok(vq)) {
+		r = -EFAULT;
+		goto err_vq;
+	}
+	if (!enable) {
+		vhost_poll_stop(&vq->poll);
+		backend = vhost_vq_get_backend(vq);
+		vhost_vq_set_backend(vq, NULL);
+	} else {
+		vhost_vq_set_backend(vq, backend);
+		r = vhost_vq_init_access(vq);
+		if (r == 0)
+			r = vhost_poll_start(&vq->poll, vq->kick);
+	}
+
+	mutex_unlock(&vq->mutex);
+
+	if (enable) {
+		vhost_test_flush_vq(n, index);
+	}
+
+	mutex_unlock(&n->dev.mutex);
+	return 0;
+
+err_vq:
+	mutex_unlock(&vq->mutex);
+err:
+	mutex_unlock(&n->dev.mutex);
+	return r;
+}
+
 static long vhost_test_ioctl(struct file *f, unsigned int ioctl,
 			     unsigned long arg)
 {
+	struct vhost_vring_file backend;
 	struct vhost_test *n = f->private_data;
 	void __user *argp = (void __user *)arg;
 	u64 __user *featurep = argp;
@@ -277,6 +330,10 @@ static long vhost_test_ioctl(struct file *f, unsigned int ioctl,
 		if (copy_from_user(&test, argp, sizeof test))
 			return -EFAULT;
 		return vhost_test_run(n, test);
+	case VHOST_TEST_SET_BACKEND:
+		if (copy_from_user(&backend, argp, sizeof backend))
+			return -EFAULT;
+		return vhost_test_set_backend(n, backend.index, backend.fd);
 	case VHOST_GET_FEATURES:
 		features = VHOST_FEATURES;
 		if (copy_to_user(featurep, &features, sizeof features))
diff --git a/drivers/vhost/test.h b/drivers/vhost/test.h
index 7dd265bfdf81..822bc4bee03a 100644
--- a/drivers/vhost/test.h
+++ b/drivers/vhost/test.h
@@ -4,5 +4,6 @@
 
 /* Start a given test on the virtio null device. 0 stops all tests. */
 #define VHOST_TEST_RUN _IOW(VHOST_VIRTIO, 0x31, int)
+#define VHOST_TEST_SET_BACKEND _IOW(VHOST_VIRTIO, 0x32, int)
 
 #endif
diff --git a/tools/virtio/virtio_test.c b/tools/virtio/virtio_test.c
index 4a2b9d11f287..6bc3e172cc9b 100644
--- a/tools/virtio/virtio_test.c
+++ b/tools/virtio/virtio_test.c
@@ -46,6 +46,9 @@ struct vdev_info {
 	struct vhost_memory *mem;
 };
 
+static const struct vhost_vring_file no_backend = { .fd = -1 },
+				     backend = { .fd = 1 };
+
 bool vq_notify(struct virtqueue *vq)
 {
 	struct vq_info *info = vq->priv;
@@ -155,10 +158,10 @@ static void wait_for_interrupt(struct vdev_info *dev)
 }
 
 static void run_test(struct vdev_info *dev, struct vq_info *vq,
-		     bool delayed, int batch, int bufs)
+		     bool delayed, int batch, int reset_n, int bufs)
 {
 	struct scatterlist sl;
-	long started = 0, completed = 0;
+	long started = 0, completed = 0, next_reset = reset_n;
 	long completed_before, started_before;
 	int r, test = 1;
 	unsigned len;
@@ -171,6 +174,7 @@ static void run_test(struct vdev_info *dev, struct vq_info *vq,
 		completed_before = completed;
 		started_before = started;
 		do {
+			const bool reset = reset_n && completed > next_reset;
 			if (random_batch)
 				batch = (random() % vq->vring.num) + 1;
 
@@ -200,12 +204,26 @@ static void run_test(struct vdev_info *dev, struct vq_info *vq,
 			if (started >= bufs)
 				r = -1;
 
+			if (reset) {
+				r = ioctl(dev->control, VHOST_TEST_SET_BACKEND,
+					  &no_backend);
+				assert(!r);
+			}
+
 			/* Flush out completed bufs if any */
 			while (virtqueue_get_buf(vq->vq, &len)) {
 				++completed;
 				r = 0;
 			}
 
+			if (reset) {
+				r = ioctl(dev->control, VHOST_TEST_SET_BACKEND,
+					  &backend);
+				assert(!r);
+
+				while (completed > next_reset)
+					next_reset += completed;
+			}
 		} while (r == 0);
 		if (completed == completed_before && started == started_before)
 			++spurious;
@@ -270,6 +288,11 @@ const struct option longopts[] = {
 		.val = 'b',
 		.has_arg = required_argument,
 	},
+	{
+		.name = "reset",
+		.val = 'r',
+		.has_arg = optional_argument,
+	},
 	{
 	}
 };
@@ -282,6 +305,7 @@ static void help(void)
 		" [--no-virtio-1]"
 		" [--delayed-interrupt]"
 		" [--batch=random/N]"
+		" [--reset=N]"
 		"\n");
 }
 
@@ -290,7 +314,7 @@ int main(int argc, char **argv)
 	struct vdev_info dev;
 	unsigned long long features = (1ULL << VIRTIO_RING_F_INDIRECT_DESC) |
 		(1ULL << VIRTIO_RING_F_EVENT_IDX) | (1ULL << VIRTIO_F_VERSION_1);
-	long batch = 1;
+	long batch = 1, reset = 0;
 	int o;
 	bool delayed = false;
 
@@ -326,6 +350,15 @@ int main(int argc, char **argv)
 				assert(batch < (long)INT_MAX + 1);
 			}
 			break;
+		case 'r':
+			if (!optarg) {
+				reset = 1;
+			} else {
+				reset = strtol(optarg, NULL, 10);
+				assert(reset > 0);
+				assert(reset < (long)INT_MAX + 1);
+			}
+			break;
 		default:
 			assert(0);
 			break;
@@ -335,6 +368,6 @@ int main(int argc, char **argv)
 done:
 	vdev_info_init(&dev, features);
 	vq_info_add(&dev, 256);
-	run_test(&dev, &dev.vqs[0], delayed, batch, 0x100000);
+	run_test(&dev, &dev.vqs[0], delayed, batch, reset, 0x100000);
 	return 0;
 }
-- 
2.18.1

[PATCH v3 5/8] tools/virtio: Use __vring_new_virtqueue in virtio_test.c

[Eugenio Pérez]

As updated in ("2a2d1382fe9d virtio: Add improved queue allocation API")

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
---
 tools/virtio/virtio_test.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/tools/virtio/virtio_test.c b/tools/virtio/virtio_test.c
index 6bc3e172cc9b..0a247ba3b899 100644
--- a/tools/virtio/virtio_test.c
+++ b/tools/virtio/virtio_test.c
@@ -105,10 +105,9 @@ static void vq_info_add(struct vdev_info *dev, int num)
 	assert(r >= 0);
 	memset(info->ring, 0, vring_size(num, 4096));
 	vring_init(&info->vring, num, info->ring, 4096);
-	info->vq = vring_new_virtqueue(info->idx,
-				       info->vring.num, 4096, &dev->vdev,
-				       true, false, info->ring,
-				       vq_notify, vq_callback, "test");
+	info->vq =
+		__vring_new_virtqueue(info->idx, info->vring, &dev->vdev, true,
+				      false, vq_notify, vq_callback, "test");
 	assert(info->vq);
 	info->vq->priv = info;
 	vhost_vq_setup(dev, info);
-- 
2.18.1

[PATCH v3 6/8] tools/virtio: Extract virtqueue initialization in vq_reset

[Eugenio Pérez]

So we can reset after that in the main loop.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
---
 tools/virtio/virtio_test.c | 21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/tools/virtio/virtio_test.c b/tools/virtio/virtio_test.c
index 0a247ba3b899..bc16c818bda3 100644
--- a/tools/virtio/virtio_test.c
+++ b/tools/virtio/virtio_test.c
@@ -94,6 +94,19 @@ void vhost_vq_setup(struct vdev_info *dev, struct vq_info *info)
 	assert(r >= 0);
 }
 
+static void vq_reset(struct vq_info *info, int num, struct virtio_device *vdev)
+{
+	if (info->vq)
+		vring_del_virtqueue(info->vq);
+
+	memset(info->ring, 0, vring_size(num, 4096));
+	vring_init(&info->vring, num, info->ring, 4096);
+	info->vq = __vring_new_virtqueue(info->idx, info->vring, vdev, true,
+					 false, vq_notify, vq_callback, "test");
+	assert(info->vq);
+	info->vq->priv = info;
+}
+
 static void vq_info_add(struct vdev_info *dev, int num)
 {
 	struct vq_info *info = &dev->vqs[dev->nvqs];
@@ -103,13 +116,7 @@ static void vq_info_add(struct vdev_info *dev, int num)
 	info->call = eventfd(0, EFD_NONBLOCK);
 	r = posix_memalign(&info->ring, 4096, vring_size(num, 4096));
 	assert(r >= 0);
-	memset(info->ring, 0, vring_size(num, 4096));
-	vring_init(&info->vring, num, info->ring, 4096);
-	info->vq =
-		__vring_new_virtqueue(info->idx, info->vring, &dev->vdev, true,
-				      false, vq_notify, vq_callback, "test");
-	assert(info->vq);
-	info->vq->priv = info;
+	vq_reset(info, num, &dev->vdev);
 	vhost_vq_setup(dev, info);
 	dev->fds[info->idx].fd = info->call;
 	dev->fds[info->idx].events = POLLIN;
-- 
2.18.1

[PATCH v3 7/8] tools/virtio: Reset index in virtio_test --reset.

[Eugenio Pérez]

This way behavior for vhost is more like a VM.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
---
 tools/virtio/virtio_test.c | 26 ++++++++++++++++++++++++--
 1 file changed, 24 insertions(+), 2 deletions(-)

diff --git a/tools/virtio/virtio_test.c b/tools/virtio/virtio_test.c
index bc16c818bda3..82902fc3ba2a 100644
--- a/tools/virtio/virtio_test.c
+++ b/tools/virtio/virtio_test.c
@@ -48,6 +48,7 @@ struct vdev_info {
 
 static const struct vhost_vring_file no_backend = { .fd = -1 },
 				     backend = { .fd = 1 };
+static const struct vhost_vring_state null_state = {};
 
 bool vq_notify(struct virtqueue *vq)
 {
@@ -173,14 +174,19 @@ static void run_test(struct vdev_info *dev, struct vq_info *vq,
 	unsigned len;
 	long long spurious = 0;
 	const bool random_batch = batch == RANDOM_BATCH;
+
 	r = ioctl(dev->control, VHOST_TEST_RUN, &test);
 	assert(r >= 0);
+	if (!reset_n) {
+		next_reset = INT_MAX;
+	}
+
 	for (;;) {
 		virtqueue_disable_cb(vq->vq);
 		completed_before = completed;
 		started_before = started;
 		do {
-			const bool reset = reset_n && completed > next_reset;
+			const bool reset = completed > next_reset;
 			if (random_batch)
 				batch = (random() % vq->vring.num) + 1;
 
@@ -223,10 +229,24 @@ static void run_test(struct vdev_info *dev, struct vq_info *vq,
 			}
 
 			if (reset) {
+				struct vhost_vring_state s = { .index = 0 };
+
+				vq_reset(vq, vq->vring.num, &dev->vdev);
+
+				r = ioctl(dev->control, VHOST_GET_VRING_BASE,
+					  &s);
+				assert(!r);
+
+				s.num = 0;
+				r = ioctl(dev->control, VHOST_SET_VRING_BASE,
+					  &null_state);
+				assert(!r);
+
 				r = ioctl(dev->control, VHOST_TEST_SET_BACKEND,
 					  &backend);
 				assert(!r);
 
+				started = completed;
 				while (completed > next_reset)
 					next_reset += completed;
 			}
@@ -248,7 +268,9 @@ static void run_test(struct vdev_info *dev, struct vq_info *vq,
 	test = 0;
 	r = ioctl(dev->control, VHOST_TEST_RUN, &test);
 	assert(r >= 0);
-	fprintf(stderr, "spurious wakeups: 0x%llx\n", spurious);
+	fprintf(stderr,
+		"spurious wakeups: 0x%llx started=0x%lx completed=0x%lx\n",
+		spurious, started, completed);
 }
 
 const char optstring[] = "h";
-- 
2.18.1

[PATCH v3 8/8] tools/virtio: Use tools/include/list.h instead of stubs

[Eugenio Pérez]

It should not make any significant difference but reduce stub code.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
---
 tools/virtio/linux/kernel.h | 7 +------
 tools/virtio/linux/virtio.h | 5 ++---
 tools/virtio/virtio_test.c  | 1 +
 tools/virtio/vringh_test.c  | 2 ++
 4 files changed, 6 insertions(+), 9 deletions(-)

diff --git a/tools/virtio/linux/kernel.h b/tools/virtio/linux/kernel.h
index 6683b4a70b05..caab980211a6 100644
--- a/tools/virtio/linux/kernel.h
+++ b/tools/virtio/linux/kernel.h
@@ -11,6 +11,7 @@
 
 #include <linux/compiler.h>
 #include <linux/types.h>
+#include <linux/list.h>
 #include <linux/printk.h>
 #include <linux/bug.h>
 #include <errno.h>
@@ -135,10 +136,4 @@ static inline void free_page(unsigned long addr)
 	(void) (&_min1 == &_min2);		\
 	_min1 < _min2 ? _min1 : _min2; })
 
-/* TODO: empty stubs for now. Broken but enough for virtio_ring.c */
-#define list_add_tail(a, b) do {} while (0)
-#define list_del(a) do {} while (0)
-#define list_for_each_entry(a, b, c) while (0)
-/* end of stubs */
-
 #endif /* KERNEL_H */
diff --git a/tools/virtio/linux/virtio.h b/tools/virtio/linux/virtio.h
index b751350d4ce8..5d90254ddae4 100644
--- a/tools/virtio/linux/virtio.h
+++ b/tools/virtio/linux/virtio.h
@@ -11,12 +11,11 @@ struct device {
 struct virtio_device {
 	struct device dev;
 	u64 features;
+	struct list_head vqs;
 };
 
 struct virtqueue {
-	/* TODO: commented as list macros are empty stubs for now.
-	 * Broken but enough for virtio_ring.c
-	 * struct list_head list; */
+	struct list_head list;
 	void (*callback)(struct virtqueue *vq);
 	const char *name;
 	struct virtio_device *vdev;
diff --git a/tools/virtio/virtio_test.c b/tools/virtio/virtio_test.c
index 82902fc3ba2a..cb3f29c09aff 100644
--- a/tools/virtio/virtio_test.c
+++ b/tools/virtio/virtio_test.c
@@ -129,6 +129,7 @@ static void vdev_info_init(struct vdev_info* dev, unsigned long long features)
 	int r;
 	memset(dev, 0, sizeof *dev);
 	dev->vdev.features = features;
+	INIT_LIST_HEAD(&dev->vdev.vqs);
 	dev->buf_size = 1024;
 	dev->buf = malloc(dev->buf_size);
 	assert(dev->buf);
diff --git a/tools/virtio/vringh_test.c b/tools/virtio/vringh_test.c
index 293653463303..fa87b58bd5fa 100644
--- a/tools/virtio/vringh_test.c
+++ b/tools/virtio/vringh_test.c
@@ -307,6 +307,7 @@ static int parallel_test(u64 features,
 		close(to_host[0]);
 
 		gvdev.vdev.features = features;
+		INIT_LIST_HEAD(&gvdev.vdev.vqs);
 		gvdev.to_host_fd = to_host[1];
 		gvdev.notifies = 0;
 
@@ -453,6 +454,7 @@ int main(int argc, char *argv[])
 
 	getrange = getrange_iov;
 	vdev.features = 0;
+	INIT_LIST_HEAD(&vdev.vqs);
 
 	while (argv[1]) {
 		if (strcmp(argv[1], "--indirect") == 0)
-- 
2.18.1