update submodule and patches to 7.1.0

[pve-qemu.git] / debian / patches / extra / 0013-virtio-scsi-don-t-waste-CPU-polling-the-event-virtqu.patch

diff --git a/debian/patches/extra/0013-virtio-scsi-don-t-waste-CPU-polling-the-event-virtqu.patch b/debian/patches/extra/0013-virtio-scsi-don-t-waste-CPU-polling-the-event-virtqu.patch
deleted file mode 100644 (file)
index 238d456..0000000
--- a/debian/patches/extra/0013-virtio-scsi-don-t-waste-CPU-polling-the-event-virtqu.patch
+++ /dev/null
@@ -1,91 +0,0 @@
-From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
-From: Stefan Hajnoczi <stefanha@redhat.com>
-Date: Wed, 27 Apr 2022 15:35:37 +0100
-Subject: [PATCH] virtio-scsi: don't waste CPU polling the event virtqueue
-
-The virtio-scsi event virtqueue is not emptied by its handler function.
-This is typical for rx virtqueues where the device uses buffers when
-some event occurs (e.g. a packet is received, an error condition
-happens, etc).
-
-Polling non-empty virtqueues wastes CPU cycles. We are not waiting for
-new buffers to become available, we are waiting for an event to occur,
-so it's a misuse of CPU resources to poll for buffers.
-
-Introduce the new virtio_queue_aio_attach_host_notifier_no_poll() API,
-which is identical to virtio_queue_aio_attach_host_notifier() except
-that it does not poll the virtqueue.
-
-Before this patch the following command-line consumed 100% CPU in the
-IOThread polling and calling virtio_scsi_handle_event():
-
-  $ qemu-system-x86_64 -M accel=kvm -m 1G -cpu host \
-      --object iothread,id=iothread0 \
-      --device virtio-scsi-pci,iothread=iothread0 \
-      --blockdev file,filename=test.img,aio=native,cache.direct=on,node-name=drive0 \
-      --device scsi-hd,drive=drive0
-
-After this patch CPU is no longer wasted.
-
-Reported-by: Nir Soffer <nsoffer@redhat.com>
-Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
-Tested-by: Nir Soffer <nsoffer@redhat.com>
-Message-id: 20220427143541.119567-3-stefanha@redhat.com
-Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
-(cherry-picked from commit 38738f7dbbda90fbc161757b7f4be35b52205552)
-Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
----
- hw/scsi/virtio-scsi-dataplane.c |  2 +-
- hw/virtio/virtio.c              | 13 +++++++++++++
- include/hw/virtio/virtio.h      |  1 +
- 3 files changed, 15 insertions(+), 1 deletion(-)
-
-diff --git a/hw/scsi/virtio-scsi-dataplane.c b/hw/scsi/virtio-scsi-dataplane.c
-index 29575cbaf6..8bb6e6acfc 100644
---- a/hw/scsi/virtio-scsi-dataplane.c
-+++ b/hw/scsi/virtio-scsi-dataplane.c
-@@ -138,7 +138,7 @@ int virtio_scsi_dataplane_start(VirtIODevice *vdev)
- 
-     aio_context_acquire(s->ctx);
-     virtio_queue_aio_attach_host_notifier(vs->ctrl_vq, s->ctx);
--    virtio_queue_aio_attach_host_notifier(vs->event_vq, s->ctx);
-+    virtio_queue_aio_attach_host_notifier_no_poll(vs->event_vq, s->ctx);
- 
-     for (i = 0; i < vs->conf.num_queues; i++) {
-         virtio_queue_aio_attach_host_notifier(vs->cmd_vqs[i], s->ctx);
-diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
-index 9d637e043e..67a873f54a 100644
---- a/hw/virtio/virtio.c
-+++ b/hw/virtio/virtio.c
-@@ -3534,6 +3534,19 @@ void virtio_queue_aio_attach_host_notifier(VirtQueue *vq, AioContext *ctx)
-                                 virtio_queue_host_notifier_aio_poll_end);
- }
- 
-+/*
-+ * Same as virtio_queue_aio_attach_host_notifier() but without polling. Use
-+ * this for rx virtqueues and similar cases where the virtqueue handler
-+ * function does not pop all elements. When the virtqueue is left non-empty
-+ * polling consumes CPU cycles and should not be used.
-+ */
-+void virtio_queue_aio_attach_host_notifier_no_poll(VirtQueue *vq, AioContext *ctx)
-+{
-+    aio_set_event_notifier(ctx, &vq->host_notifier, true,
-+                           virtio_queue_host_notifier_read,
-+                           NULL, NULL);
-+}
-+
- void virtio_queue_aio_detach_host_notifier(VirtQueue *vq, AioContext *ctx)
- {
-     aio_set_event_notifier(ctx, &vq->host_notifier, true, NULL, NULL, NULL);
-diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h
-index b31c4507f5..b62a35fdca 100644
---- a/include/hw/virtio/virtio.h
-+++ b/include/hw/virtio/virtio.h
-@@ -317,6 +317,7 @@ EventNotifier *virtio_queue_get_host_notifier(VirtQueue *vq);
- void virtio_queue_set_host_notifier_enabled(VirtQueue *vq, bool enabled);
- void virtio_queue_host_notifier_read(EventNotifier *n);
- void virtio_queue_aio_attach_host_notifier(VirtQueue *vq, AioContext *ctx);
-+void virtio_queue_aio_attach_host_notifier_no_poll(VirtQueue *vq, AioContext *ctx);
- void virtio_queue_aio_detach_host_notifier(VirtQueue *vq, AioContext *ctx);
- VirtQueue *virtio_vector_first_queue(VirtIODevice *vdev, uint16_t vector);
- VirtQueue *virtio_vector_next_queue(VirtQueue *vq);