[PATCH v3 5/8] tools/virtio: Add --batch option

Eugenio Pérez
2020-03-31T19:28:32Z

This allow to test vhost having >1 buffers in flight

Signed-off-by: Eugenio Pérez <eperezma@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