[dpdk-stable] patch 'vhost: fix vhost interrupt support' has been queued to stable release 18.08.1

[Kevin Traynor <ktraynor@redhat.com>]

Hi,

FYI, your patch has been queued to stable release 18.08.1

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 11/23/18. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the patch applied
to the branch. If the code is different (ie: not only metadata diffs), due for example to
a change in context or macro names, please double check it.

Thanks.

Kevin Traynor

---
>From 97b28091a42d73c92fe2c6ec354559815e005fd0 Mon Sep 17 00:00:00 2001
From: Tiwei Bie <tiwei.bie@intel.com>
Date: Wed, 5 Sep 2018 07:55:55 +0800
Subject: [PATCH] vhost: fix vhost interrupt support

[ upstream commit 77de7c781cb6dbbf11c00118946fb4e46347116f ]

When VIRTIO_RING_F_EVENT_IDX is negotiated, we need to
update the avail event to enable the notification.

Fixes: 3f8ff12821e4 ("vhost: support interrupt mode")

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
---
 lib/librte_vhost/Makefile    |  1 +
 lib/librte_vhost/meson.build |  1 +
 lib/librte_vhost/vhost.c     | 18 ++++++++++++------
 lib/librte_vhost/vhost.h     |  2 ++
 4 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/lib/librte_vhost/Makefile b/lib/librte_vhost/Makefile
index de431fbb7..531cf4832 100644
--- a/lib/librte_vhost/Makefile
+++ b/lib/librte_vhost/Makefile
@@ -14,4 +14,5 @@ CFLAGS += -DALLOW_EXPERIMENTAL_API
 CFLAGS += $(WERROR_FLAGS) -I$(SRCDIR) -O3 -D_FILE_OFFSET_BITS=64
 CFLAGS += -I vhost_user
+CFLAGS += -fno-strict-aliasing
 LDLIBS += -lpthread
 
diff --git a/lib/librte_vhost/meson.build b/lib/librte_vhost/meson.build
index bd62e0e39..9d25b4d88 100644
--- a/lib/librte_vhost/meson.build
+++ b/lib/librte_vhost/meson.build
@@ -10,4 +10,5 @@ endif
 version = 4
 allow_experimental_apis = true
+cflags += '-fno-strict-aliasing'
 sources = files('fd_man.c', 'iotlb.c', 'socket.c', 'vdpa.c',
 		'vhost.c', 'vhost_user.c',
diff --git a/lib/librte_vhost/vhost.c b/lib/librte_vhost/vhost.c
index 3c9be10a0..88b1781d5 100644
--- a/lib/librte_vhost/vhost.c
+++ b/lib/librte_vhost/vhost.c
@@ -647,10 +647,16 @@ rte_vhost_avail_entries(int vid, uint16_t queue_id)
 
 static inline void
-vhost_enable_notify_split(struct vhost_virtqueue *vq, int enable)
+vhost_enable_notify_split(struct virtio_net *dev,
+		struct vhost_virtqueue *vq, int enable)
 {
-	if (enable)
-		vq->used->flags &= ~VRING_USED_F_NO_NOTIFY;
-	else
-		vq->used->flags |= VRING_USED_F_NO_NOTIFY;
+	if (!(dev->features & (1ULL << VIRTIO_RING_F_EVENT_IDX))) {
+		if (enable)
+			vq->used->flags &= ~VRING_USED_F_NO_NOTIFY;
+		else
+			vq->used->flags |= VRING_USED_F_NO_NOTIFY;
+	} else {
+		if (enable)
+			vhost_avail_event(vq) = vq->last_avail_idx;
+	}
 }
 
@@ -690,5 +696,5 @@ rte_vhost_enable_guest_notification(int vid, uint16_t queue_id, int enable)
 		vhost_enable_notify_packed(dev, vq, enable);
 	else
-		vhost_enable_notify_split(vq, enable);
+		vhost_enable_notify_split(dev, vq, enable);
 
 	return 0;
diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
index 760a09c0d..25ffd7614 100644
--- a/lib/librte_vhost/vhost.h
+++ b/lib/librte_vhost/vhost.h
@@ -649,4 +649,6 @@ vhost_iova_to_vva(struct virtio_net *dev, struct vhost_virtqueue *vq,
 }
 
+#define vhost_avail_event(vr) \
+	(*(volatile uint16_t*)&(vr)->used->ring[(vr)->size])
 #define vhost_used_event(vr) \
 	(*(volatile uint16_t*)&(vr)->avail->ring[(vr)->size])
-- 
2.19.0

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2018-11-20 17:53:08.164108481 +0000
+++ 0029-vhost-fix-vhost-interrupt-support.patch	2018-11-20 17:53:07.000000000 +0000
@@ -1,13 +1,14 @@
-From 77de7c781cb6dbbf11c00118946fb4e46347116f Mon Sep 17 00:00:00 2001
+From 97b28091a42d73c92fe2c6ec354559815e005fd0 Mon Sep 17 00:00:00 2001
 From: Tiwei Bie <tiwei.bie@intel.com>
 Date: Wed, 5 Sep 2018 07:55:55 +0800
 Subject: [PATCH] vhost: fix vhost interrupt support
 
+[ upstream commit 77de7c781cb6dbbf11c00118946fb4e46347116f ]
+
 When VIRTIO_RING_F_EVENT_IDX is negotiated, we need to
 update the avail event to enable the notification.
 
 Fixes: 3f8ff12821e4 ("vhost: support interrupt mode")
-Cc: stable@dpdk.org
 
 Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
 Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
@@ -39,10 +40,10 @@
  sources = files('fd_man.c', 'iotlb.c', 'socket.c', 'vdpa.c',
  		'vhost.c', 'vhost_user.c',
 diff --git a/lib/librte_vhost/vhost.c b/lib/librte_vhost/vhost.c
-index 91026b3e1..e62f4c594 100644
+index 3c9be10a0..88b1781d5 100644
 --- a/lib/librte_vhost/vhost.c
 +++ b/lib/librte_vhost/vhost.c
-@@ -648,10 +648,16 @@ rte_vhost_avail_entries(int vid, uint16_t queue_id)
+@@ -647,10 +647,16 @@ rte_vhost_avail_entries(int vid, uint16_t queue_id)
  
  static inline void
 -vhost_enable_notify_split(struct vhost_virtqueue *vq, int enable)
@@ -64,7 +65,7 @@
 +	}
  }
  
-@@ -691,5 +697,5 @@ rte_vhost_enable_guest_notification(int vid, uint16_t queue_id, int enable)
+@@ -690,5 +696,5 @@ rte_vhost_enable_guest_notification(int vid, uint16_t queue_id, int enable)
  		vhost_enable_notify_packed(dev, vq, enable);
  	else
 -		vhost_enable_notify_split(vq, enable);