[PATCH v3 7/8] tools/virtio: Add --reset=random

Eugenio Pérez
2020-03-31T19:28:40Z

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 | 44 ++++++++++++++++++++++++++---
3 files changed, 98 insertions(+), 4 deletions(-)

diff --git a/drivers/vhost/test.c b/drivers/vhost/test.c
index 4b00cd4266ad..102066515b48 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 *private_data;
+
+ 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);
+ private_data = vq->private_data;
+ vq->private_data = NULL;
+ } else {
+ r = vhost_vq_init_access(vq);
+ vq->private_data = private_data;
+ 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..93d81cd64ba0 100644
--- a/tools/virtio/virtio_test.c
+++ b/tools/virtio/virtio_test.c
@@ -20,6 +20,7 @@
#include "../../drivers/vhost/test.h"

#define RANDOM_BATCH -1
+#define RANDOM_RESET -1

/* Unused */
void *__kmalloc_fake, *__kfree_ignore_start, *__kfree_ignore_end;
@@ -46,6 +47,9 @@ 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 +159,10 @@ 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 +175,7 @@ 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 +205,26 @@ 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 +289,11 @@ const struct option longopts[] = {
.val = 'b',
.has_arg = required_argument,
},
+ {
+ .name = "reset",
+ .val = 'r',
+ .has_arg = optional_argument,
+ },
{
}
};
@@ -282,6 +306,7 @@ static void help(void)
" [--no-virtio-1]"
" [--delayed-interrupt]"
" [--batch=random/N]"
+ " [--reset=random/N]"
"\n");
}

@@ -290,7 +315,7 @@ 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 +351,17 @@ int main(int argc, char **argv)
assert(batch < (long)INT_MAX + 1);
}
break;
+ case 'r':
+ if (!optarg) {
+ reset = 1;
+ } else if (0 == strcmp(optarg, "random")) {
+ reset = RANDOM_RESET;
+ } else {
+ reset = strtol(optarg, NULL, 10);
+ assert(reset >= 0);
+ assert(reset < (long)INT_MAX + 1);
+ }
+ break;
default:
assert(0);
break;
@@ -335,6 +371,6 @@ 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