qemu-kvm/kvm-vhost-add-vhost_svq_poll.patch
Miroslav Rezanina 23d471091d * Mon Aug 08 2022 Miroslav Rezanina <mrezanin@redhat.com> - 7.0.0-10
- kvm-vhost-Track-descriptor-chain-in-private-at-SVQ.patch [bz#1939363]
- kvm-vhost-Fix-device-s-used-descriptor-dequeue.patch [bz#1939363]
- kvm-hw-virtio-Replace-g_memdup-by-g_memdup2.patch [bz#1939363]
- kvm-vhost-Fix-element-in-vhost_svq_add-failure.patch [bz#1939363]
- kvm-meson-create-have_vhost_-variables.patch [bz#1939363]
- kvm-meson-use-have_vhost_-variables-to-pick-sources.patch [bz#1939363]
- kvm-vhost-move-descriptor-translation-to-vhost_svq_vring.patch [bz#1939363]
- kvm-virtio-net-Expose-MAC_TABLE_ENTRIES.patch [bz#1939363]
- kvm-virtio-net-Expose-ctrl-virtqueue-logic.patch [bz#1939363]
- kvm-vdpa-Avoid-compiler-to-squash-reads-to-used-idx.patch [bz#1939363]
- kvm-vhost-Reorder-vhost_svq_kick.patch [bz#1939363]
- kvm-vhost-Move-vhost_svq_kick-call-to-vhost_svq_add.patch [bz#1939363]
- kvm-vhost-Check-for-queue-full-at-vhost_svq_add.patch [bz#1939363]
- kvm-vhost-Decouple-vhost_svq_add-from-VirtQueueElement.patch [bz#1939363]
- kvm-vhost-Add-SVQDescState.patch [bz#1939363]
- kvm-vhost-Track-number-of-descs-in-SVQDescState.patch [bz#1939363]
- kvm-vhost-add-vhost_svq_push_elem.patch [bz#1939363]
- kvm-vhost-Expose-vhost_svq_add.patch [bz#1939363]
- kvm-vhost-add-vhost_svq_poll.patch [bz#1939363]
- kvm-vhost-Add-svq-avail_handler-callback.patch [bz#1939363]
- kvm-vdpa-Export-vhost_vdpa_dma_map-and-unmap-calls.patch [bz#1939363]
- kvm-vhost-net-vdpa-add-stubs-for-when-no-virtio-net-devi.patch [bz#1939363]
- kvm-vdpa-manual-forward-CVQ-buffers.patch [bz#1939363]
- kvm-vdpa-Buffer-CVQ-support-on-shadow-virtqueue.patch [bz#1939363]
- kvm-vdpa-Extract-get-features-part-from-vhost_vdpa_get_m.patch [bz#1939363]
- kvm-vdpa-Add-device-migration-blocker.patch [bz#1939363]
- kvm-vdpa-Add-x-svq-to-NetdevVhostVDPAOptions.patch [bz#1939363]
- kvm-redhat-Update-linux-headers-linux-kvm.h-to-v5.18-rc6.patch [bz#2111994]
- kvm-target-s390x-kvm-Honor-storage-keys-during-emulation.patch [bz#2111994]
- kvm-kvm-don-t-use-perror-without-useful-errno.patch [bz#2095608]
- kvm-multifd-Copy-pages-before-compressing-them-with-zlib.patch [bz#2099934]
- kvm-Revert-migration-Simplify-unqueue_page.patch [bz#2099934]
- Resolves: bz#1939363
  (vDPA control virtqueue support in Qemu)
- Resolves: bz#2111994
  (RHEL9: skey test in kvm_unit_test got failed)
- Resolves: bz#2095608
  (Please correct the error message when try to start qemu with "-M kernel-irqchip=split")
- Resolves: bz#2099934
  (Guest reboot on destination host after postcopy migration completed)
2022-08-08 04:22:43 -04:00

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