93 lines
3.0 KiB
Diff
93 lines
3.0 KiB
Diff
|
From 0ab3da1092362470d256b433c546bd365d34f930 Mon Sep 17 00:00:00 2001
|
||
|
|
From: =?UTF-8?q?Eugenio=20P=C3=A9rez?= <eperezma@redhat.com>
|
||
|
|
Date: Thu, 21 Jul 2022 15:38:55 +0200
|
||
|
|
Subject: [PATCH 19/32] vhost: add vhost_svq_poll
|
||
|
|
MIME-Version: 1.0
|
||
|
|
Content-Type: text/plain; charset=UTF-8
|
||
|
|
Content-Transfer-Encoding: 8bit
|
||
|
|
|
||
|
|
RH-Author: Eugenio Pérez <eperezma@redhat.com>
|
||
|
|
RH-MergeRequest: 108: Net Control Virtqueue shadow Support
|
||
|
|
RH-Commit: [19/27] 6807bb0bb6e5183b46a03b12b4027c7d767e8555 (eperezmartin/qemu-kvm)
|
||
|
|
RH-Bugzilla: 1939363
|
||
|
|
RH-Acked-by: Stefano Garzarella <sgarzare@redhat.com>
|
||
|
|
RH-Acked-by: Cindy Lu <lulu@redhat.com>
|
||
|
|
RH-Acked-by: Laurent Vivier <lvivier@redhat.com>
|
||
|
|
|
||
|
|
Bugzilla: https://bugzilla.redhat.com/1939363
|
||
|
|
|
||
|
|
Upstream Status: git://git.qemu.org/qemu.git
|
||
|
|
|
||
|
|
commit 3f44d13dda83d390cc9563e56e7d337e4f6223f4
|
||
|
|
Author: Eugenio Pérez <eperezma@redhat.com>
|
||
|
|
Date: Wed Jul 20 08:59:38 2022 +0200
|
||
|
|
|
||
|
|
vhost: add vhost_svq_poll
|
||
|
|
|
||
|
|
It allows the Shadow Control VirtQueue to wait for the device to use the
|
||
|
|
available buffers.
|
||
|
|
|
||
|
|
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
|
||
|
|
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
|
||
|
|
Signed-off-by: Jason Wang <jasowang@redhat.com>
|
||
|
|
|
||
|
|
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
|
||
|
|
---
|
||
|
|
hw/virtio/vhost-shadow-virtqueue.c | 27 +++++++++++++++++++++++++++
|
||
|
|
hw/virtio/vhost-shadow-virtqueue.h | 1 +
|
||
|
|
2 files changed, 28 insertions(+)
|
||
|
|
|
||
|
|
diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c
|
||
|
|
index cb879e7b88..95d0d7a7ee 100644
|
||
|
|
--- a/hw/virtio/vhost-shadow-virtqueue.c
|
||
|
|
+++ b/hw/virtio/vhost-shadow-virtqueue.c
|
||
|
|
@@ -485,6 +485,33 @@ static void vhost_svq_flush(VhostShadowVirtqueue *svq,
|
||
|
|
} while (!vhost_svq_enable_notification(svq));
|
||
|
|
}
|
||
|
|
|
||
|
|
+/**
|
||
|
|
+ * Poll the SVQ for one device used buffer.
|
||
|
|
+ *
|
||
|
|
+ * This function race with main event loop SVQ polling, so extra
|
||
|
|
+ * synchronization is needed.
|
||
|
|
+ *
|
||
|
|
+ * Return the length written by the device.
|
||
|
|
+ */
|
||
|
|
+size_t vhost_svq_poll(VhostShadowVirtqueue *svq)
|
||
|
|
+{
|
||
|
|
+ int64_t start_us = g_get_monotonic_time();
|
||
|
|
+ do {
|
||
|
|
+ uint32_t len;
|
||
|
|
+ VirtQueueElement *elem = vhost_svq_get_buf(svq, &len);
|
||
|
|
+ if (elem) {
|
||
|
|
+ return len;
|
||
|
|
+ }
|
||
|
|
+
|
||
|
|
+ if (unlikely(g_get_monotonic_time() - start_us > 10e6)) {
|
||
|
|
+ return 0;
|
||
|
|
+ }
|
||
|
|
+
|
||
|
|
+ /* Make sure we read new used_idx */
|
||
|
|
+ smp_rmb();
|
||
|
|
+ } while (true);
|
||
|
|
+}
|
||
|
|
+
|
||
|
|
/**
|
||
|
|
* Forward used buffers.
|
||
|
|
*
|
||
|
|
diff --git a/hw/virtio/vhost-shadow-virtqueue.h b/hw/virtio/vhost-shadow-virtqueue.h
|
||
|
|
index dd78f4bec2..cf442f7dea 100644
|
||
|
|
--- a/hw/virtio/vhost-shadow-virtqueue.h
|
||
|
|
+++ b/hw/virtio/vhost-shadow-virtqueue.h
|
||
|
|
@@ -89,6 +89,7 @@ void vhost_svq_push_elem(VhostShadowVirtqueue *svq,
|
||
|
|
int vhost_svq_add(VhostShadowVirtqueue *svq, const struct iovec *out_sg,
|
||
|
|
size_t out_num, const struct iovec *in_sg, size_t in_num,
|
||
|
|
VirtQueueElement *elem);
|
||
|
|
+size_t vhost_svq_poll(VhostShadowVirtqueue *svq);
|
||
|
|
|
||
|
|
void vhost_svq_set_svq_kick_fd(VhostShadowVirtqueue *svq, int svq_kick_fd);
|
||
|
|
void vhost_svq_set_svq_call_fd(VhostShadowVirtqueue *svq, int call_fd);
|
||
|
|
--
|
||
|
|
2.31.1
|
||
|
|
|