tools/virtio: Add --batch option

[sfrench/cifs-2.6.git] / tools / virtio / virtio_test.c

diff --git a/tools/virtio/virtio_test.c b/tools/virtio/virtio_test.c
index b427def67e7e5272391bafd20152be6f454c8c77..c30de9088f3cc4ef230972af0eca3dc5233879d6 100644 (file)
--- 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;
 }