2023-12-01 12:03:14

by Yunsheng Lin

[permalink] [raw]
Subject: [PATCH RFC 6/6] tools: virtio: introduce vhost_net_test

introduce vhost_net_test basing on virtio_test to test
vhost_net changing in the kernel.

Signed-off-by: Yunsheng Lin <[email protected]>
---
tools/virtio/Makefile | 8 +-
tools/virtio/vhost_net_test.c | 441 ++++++++++++++++++++++++++++++++++
2 files changed, 446 insertions(+), 3 deletions(-)
create mode 100644 tools/virtio/vhost_net_test.c

diff --git a/tools/virtio/Makefile b/tools/virtio/Makefile
index d128925980e0..e25e99c1c3b7 100644
--- a/tools/virtio/Makefile
+++ b/tools/virtio/Makefile
@@ -1,8 +1,9 @@
# SPDX-License-Identifier: GPL-2.0
all: test mod
-test: virtio_test vringh_test
+test: virtio_test vringh_test vhost_net_test
virtio_test: virtio_ring.o virtio_test.o
vringh_test: vringh_test.o vringh.o virtio_ring.o
+vhost_net_test: virtio_ring.o vhost_net_test.o

try-run = $(shell set -e; \
if ($(1)) >/dev/null 2>&1; \
@@ -49,6 +50,7 @@ oot-clean: OOT_BUILD+=clean

.PHONY: all test mod clean vhost oot oot-clean oot-build
clean:
- ${RM} *.o vringh_test virtio_test vhost_test/*.o vhost_test/.*.cmd \
- vhost_test/Module.symvers vhost_test/modules.order *.d
+ ${RM} *.o vringh_test virtio_test vhost_net_test vhost_test/*.o \
+ vhost_test/.*.cmd vhost_test/Module.symvers \
+ vhost_test/modules.order *.d
-include *.d
diff --git a/tools/virtio/vhost_net_test.c b/tools/virtio/vhost_net_test.c
new file mode 100644
index 000000000000..7e7b7aba3668
--- /dev/null
+++ b/tools/virtio/vhost_net_test.c
@@ -0,0 +1,441 @@
+// 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>
+#include <stdlib.h>
+#include <assert.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <fcntl.h>
+#include <stdbool.h>
+#include <linux/virtio_types.h>
+#include <linux/vhost.h>
+#include <linux/virtio.h>
+#include <linux/virtio_ring.h>
+#include <linux/if.h>
+#include <linux/if_tun.h>
+
+#define RANDOM_BATCH -1
+
+static int tun_alloc(void)
+{
+ struct ifreq ifr;
+ int fd, e;
+
+ fd = open("/dev/net/tun", O_RDWR);
+ if (fd < 0) {
+ perror("Cannot open /dev/net/tun");
+ return fd;
+ }
+
+ memset(&ifr, 0, sizeof(ifr));
+
+ ifr.ifr_flags = IFF_TUN | IFF_NO_PI;
+ strncpy(ifr.ifr_name, "tun0", IFNAMSIZ);
+
+ e = ioctl(fd, TUNSETIFF, (void *) &ifr);
+ if (e < 0) {
+ perror("ioctl[TUNSETIFF]");
+ close(fd);
+ return e;
+ }
+
+ return fd;
+}
+
+/* Unused */
+void *__kmalloc_fake, *__kfree_ignore_start, *__kfree_ignore_end;
+
+struct vq_info {
+ int kick;
+ int call;
+ int num;
+ int idx;
+ void *ring;
+ /* copy used for control */
+ struct vring vring;
+ struct virtqueue *vq;
+};
+
+struct vdev_info {
+ struct virtio_device vdev;
+ int control;
+ struct pollfd fds[1];
+ struct vq_info vqs[1];
+ int nvqs;
+ void *buf;
+ size_t buf_size;
+ struct vhost_memory *mem;
+};
+
+static struct vhost_vring_file no_backend = { .index = 1, .fd = -1 },
+ backend = { .index = 1, .fd = 1 };
+static const struct vhost_vring_state null_state = {};
+
+bool vq_notify(struct virtqueue *vq)
+{
+ struct vq_info *info = vq->priv;
+ unsigned long long v = 1;
+ int r;
+ r = write(info->kick, &v, sizeof v);
+ assert(r == sizeof v);
+ return true;
+}
+
+void vq_callback(struct virtqueue *vq)
+{
+}
+
+
+void vhost_vq_setup(struct vdev_info *dev, struct vq_info *info)
+{
+ struct vhost_vring_state state = { .index = info->idx };
+ struct vhost_vring_file file = { .index = info->idx };
+ unsigned long long features = dev->vdev.features;
+ struct vhost_vring_addr addr = {
+ .index = info->idx,
+ .desc_user_addr = (uint64_t)(unsigned long)info->vring.desc,
+ .avail_user_addr = (uint64_t)(unsigned long)info->vring.avail,
+ .used_user_addr = (uint64_t)(unsigned long)info->vring.used,
+ };
+ int r;
+ r = ioctl(dev->control, VHOST_SET_FEATURES, &features);
+ assert(r >= 0);
+ state.num = info->vring.num;
+ r = ioctl(dev->control, VHOST_SET_VRING_NUM, &state);
+ assert(r >= 0);
+ state.num = 0;
+ r = ioctl(dev->control, VHOST_SET_VRING_BASE, &state);
+ assert(r >= 0);
+ r = ioctl(dev->control, VHOST_SET_VRING_ADDR, &addr);
+ assert(r >= 0);
+ file.fd = info->kick;
+ r = ioctl(dev->control, VHOST_SET_VRING_KICK, &file);
+ assert(r >= 0);
+ file.fd = info->call;
+ r = ioctl(dev->control, VHOST_SET_VRING_CALL, &file);
+ 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, num, 4096, vdev, true, false,
+ info->ring, 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];
+ int r;
+
+ /* use VHOST_NET_VQ_TX for testing */
+ info->idx = 1;
+ info->kick = eventfd(0, EFD_NONBLOCK);
+ info->call = eventfd(0, EFD_NONBLOCK);
+ r = posix_memalign(&info->ring, 4096, vring_size(num, 4096));
+ assert(r >= 0);
+ vq_reset(info, num, &dev->vdev);
+ vhost_vq_setup(dev, info);
+ dev->fds[0].fd = info->call;
+ dev->fds[0].events = POLLIN;
+ dev->nvqs++;
+}
+
+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);
+ spin_lock_init(&dev->vdev.vqs_list_lock);
+ dev->buf_size = 1024;
+ dev->buf = malloc(dev->buf_size);
+ assert(dev->buf);
+ dev->control = open("/dev/vhost-net", O_RDWR);
+ assert(dev->control >= 0);
+ r = ioctl(dev->control, VHOST_SET_OWNER, NULL);
+ assert(r >= 0);
+ dev->mem = malloc(offsetof(struct vhost_memory, regions) +
+ sizeof dev->mem->regions[0]);
+ assert(dev->mem);
+ memset(dev->mem, 0, offsetof(struct vhost_memory, regions) +
+ sizeof dev->mem->regions[0]);
+ dev->mem->nregions = 1;
+ dev->mem->regions[0].guest_phys_addr = (long)dev->buf;
+ dev->mem->regions[0].userspace_addr = (long)dev->buf;
+ dev->mem->regions[0].memory_size = dev->buf_size;
+ r = ioctl(dev->control, VHOST_SET_MEM_TABLE, dev->mem);
+ assert(r >= 0);
+}
+
+/* TODO: this is pretty bad: we get a cache line bounce
+ * for the wait queue on poll and another one on read,
+ * plus the read which is there just to clear the
+ * current state. */
+static void wait_for_interrupt(struct vdev_info *dev)
+{
+ int i;
+ unsigned long long val;
+ poll(dev->fds, dev->nvqs, -1);
+ for (i = 0; i < dev->nvqs; ++i)
+ if (dev->fds[i].revents & POLLIN) {
+ read(dev->fds[i].fd, &val, sizeof val);
+ }
+}
+
+static void run_test(struct vdev_info *dev, struct vq_info *vq,
+ bool delayed, int batch, int reset_n, int bufs)
+{
+ struct scatterlist sl;
+ long started = 0, completed = 0, next_reset = reset_n;
+ long completed_before, started_before;
+ int r;
+ unsigned int len;
+ long long spurious = 0;
+ const bool random_batch = batch == RANDOM_BATCH;
+
+ r = ioctl(dev->control, VHOST_NET_SET_BACKEND, &backend);
+ assert(!r);
+
+ if (!reset_n) {
+ next_reset = INT_MAX;
+ }
+
+ for (;;) {
+ virtqueue_disable_cb(vq->vq);
+ completed_before = completed;
+ started_before = started;
+ do {
+ const bool reset = completed > next_reset;
+ if (random_batch)
+ batch = (random() % vq->vring.num) + 1;
+
+ 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 (unlikely(r != 0)) {
+ if (r == -ENOSPC &&
+ started > started_before)
+ r = 0;
+ else
+ r = -1;
+ break;
+ }
+
+ ++started;
+
+ if (unlikely(!virtqueue_kick(vq->vq))) {
+ r = -1;
+ break;
+ }
+ }
+
+ if (started >= bufs)
+ r = -1;
+
+ if (reset) {
+ r = ioctl(dev->control, VHOST_NET_SET_BACKEND,
+ &no_backend);
+ assert(!r);
+ }
+
+ /* Flush out completed bufs if any */
+ while (virtqueue_get_buf(vq->vq, &len)) {
+ ++completed;
+ r = 0;
+ }
+
+ 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_NET_SET_BACKEND,
+ &backend);
+ assert(!r);
+
+ started = completed;
+ while (completed > next_reset)
+ next_reset += completed;
+ }
+ } while (r == 0);
+ if (completed == completed_before && started == started_before)
+ ++spurious;
+ assert(completed <= bufs);
+ assert(started <= bufs);
+ if (completed == bufs)
+ break;
+ if (delayed) {
+ if (virtqueue_enable_cb_delayed(vq->vq))
+ wait_for_interrupt(dev);
+ } else {
+ if (virtqueue_enable_cb(vq->vq))
+ wait_for_interrupt(dev);
+ }
+ }
+ fprintf(stderr,
+ "spurious wakeups: 0x%llx started=0x%lx completed=0x%lx\n",
+ spurious, started, completed);
+}
+
+const char optstring[] = "h";
+const struct option longopts[] = {
+ {
+ .name = "help",
+ .val = 'h',
+ },
+ {
+ .name = "event-idx",
+ .val = 'E',
+ },
+ {
+ .name = "no-event-idx",
+ .val = 'e',
+ },
+ {
+ .name = "indirect",
+ .val = 'I',
+ },
+ {
+ .name = "no-indirect",
+ .val = 'i',
+ },
+ {
+ .name = "virtio-1",
+ .val = '1',
+ },
+ {
+ .name = "no-virtio-1",
+ .val = '0',
+ },
+ {
+ .name = "delayed-interrupt",
+ .val = 'D',
+ },
+ {
+ .name = "no-delayed-interrupt",
+ .val = 'd',
+ },
+ {
+ .name = "buf-num",
+ .val = 'n',
+ .has_arg = required_argument,
+ },
+ {
+ .name = "batch",
+ .val = 'b',
+ .has_arg = required_argument,
+ },
+ {
+ .name = "reset",
+ .val = 'r',
+ .has_arg = optional_argument,
+ },
+ {
+ }
+};
+
+static void help(int status)
+{
+ fprintf(stderr, "Usage: virtio_test [--help]"
+ " [--no-indirect]"
+ " [--no-event-idx]"
+ " [--no-virtio-1]"
+ " [--delayed-interrupt]"
+ " [--batch=random/N]"
+ " [--reset=N]"
+ "\n");
+
+ exit(status);
+}
+
+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, reset = 0, nbufs = 0x100000;
+ int o;
+ bool delayed = false;
+
+ for (;;) {
+ o = getopt_long(argc, argv, optstring, longopts, NULL);
+ switch (o) {
+ case -1:
+ goto done;
+ case '?':
+ help(2);
+ case 'e':
+ features &= ~(1ULL << VIRTIO_RING_F_EVENT_IDX);
+ break;
+ case 'h':
+ help(0);
+ case 'i':
+ features &= ~(1ULL << VIRTIO_RING_F_INDIRECT_DESC);
+ break;
+ case '0':
+ features &= ~(1ULL << VIRTIO_F_VERSION_1);
+ break;
+ case 'D':
+ delayed = true;
+ break;
+ case 'b':
+ if (0 == strcmp(optarg, "random")) {
+ batch = RANDOM_BATCH;
+ } else {
+ batch = strtol(optarg, NULL, 10);
+ assert(batch > 0);
+ 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;
+ case 'n':
+ nbufs = strtol(optarg, NULL, 10);
+ assert(nbufs > 0);
+ break;
+ default:
+ assert(0);
+ break;
+ }
+ }
+
+done:
+ backend.fd = tun_alloc();
+ assert(backend.fd >= 0);
+ vdev_info_init(&dev, features);
+ vq_info_add(&dev, 256);
+ run_test(&dev, &dev.vqs[0], delayed, batch, reset, nbufs);
+ return 0;
+}
--
2.33.0