[dpdk-stable] patch 'net/virtio-user: fix memory hotplug support in vhost-kernel' has been queued to stable release 18.08.1

[Kevin Traynor]

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 4a4c3a7150f1fb714a7057e44672330c997d3d1b Mon Sep 17 00:00:00 2001
From: Tiwei Bie <tiwei.bie at intel.com>
Date: Wed, 5 Sep 2018 12:28:52 +0800
Subject: [PATCH] net/virtio-user: fix memory hotplug support in vhost-kernel

[ upstream commit 757286542560ab7f326ae71f5ef8d83050ee5646 ]

It's possible to have much more hugepage backed memory regions
than what vhost-kernel supports due to the memory hotplug, which
may cause problems. A better solution is to have the virtio-user
pass all the memory ranges reserved by DPDK to vhost-kernel.

Fixes: 12ecb2f63b12 ("net/virtio-user: support memory hotplug")

Signed-off-by: Tiwei Bie <tiwei.bie at intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin at redhat.com>
---
 drivers/net/virtio/virtio_user/vhost_kernel.c | 38 +++++++++----------
 1 file changed, 18 insertions(+), 20 deletions(-)

diff --git a/drivers/net/virtio/virtio_user/vhost_kernel.c b/drivers/net/virtio/virtio_user/vhost_kernel.c
index a93fe5b28..b3bfcb76f 100644
--- a/drivers/net/virtio/virtio_user/vhost_kernel.c
+++ b/drivers/net/virtio/virtio_user/vhost_kernel.c
@@ -71,33 +71,34 @@ static uint64_t vhost_req_user_to_kernel[] = {
 };
 
-struct walk_arg {
-	struct vhost_memory_kernel *vm;
-	uint32_t region_nr;
-};
 static int
-add_memory_region(const struct rte_memseg_list *msl __rte_unused,
-		const struct rte_memseg *ms, size_t len, void *arg)
+add_memseg_list(const struct rte_memseg_list *msl, void *arg)
 {
-	struct walk_arg *wa = arg;
+	struct vhost_memory_kernel *vm = arg;
 	struct vhost_memory_region *mr;
 	void *start_addr;
+	uint64_t len;
 
-	if (wa->region_nr >= max_regions)
+	if (vm->nregions >= max_regions)
 		return -1;
 
-	mr = &wa->vm->regions[wa->region_nr++];
-	start_addr = ms->addr;
+	start_addr = msl->base_va;
+	len = msl->page_sz * msl->memseg_arr.len;
+
+	mr = &vm->regions[vm->nregions++];
 
 	mr->guest_phys_addr = (uint64_t)(uintptr_t)start_addr;
 	mr->userspace_addr = (uint64_t)(uintptr_t)start_addr;
 	mr->memory_size = len;
-	mr->mmap_offset = 0;
+	mr->mmap_offset = 0; /* flags_padding */
+
+	PMD_DRV_LOG(DEBUG, "index=%u addr=%p len=%" PRIu64,
+			vm->nregions - 1, start_addr, len);
 
 	return 0;
 }
 
-/* By default, vhost kernel module allows 64 regions, but DPDK allows
- * 256 segments. As a relief, below function merges those virtually
- * adjacent memsegs into one region.
+/* By default, vhost kernel module allows 64 regions, but DPDK may
+ * have much more memory regions. Below function will treat each
+ * contiguous memory space reserved by DPDK as one region.
  */
 static struct vhost_memory_kernel *
@@ -105,5 +106,4 @@ prepare_vhost_memory_kernel(void)
 {
 	struct vhost_memory_kernel *vm;
-	struct walk_arg wa;
 
 	vm = malloc(sizeof(struct vhost_memory_kernel) +
@@ -113,6 +113,6 @@ prepare_vhost_memory_kernel(void)
 		return NULL;
 
-	wa.region_nr = 0;
-	wa.vm = vm;
+	vm->nregions = 0;
+	vm->padding = 0;
 
 	/*
@@ -120,11 +120,9 @@ prepare_vhost_memory_kernel(void)
 	 * or virtio_user_start_device().
 	 */
-	if (rte_memseg_contig_walk_thread_unsafe(add_memory_region, &wa) < 0) {
+	if (rte_memseg_list_walk_thread_unsafe(add_memseg_list, vm) < 0) {
 		free(vm);
 		return NULL;
 	}
 
-	vm->nregions = wa.region_nr;
-	vm->padding = 0;
 	return vm;
 }
-- 
2.19.0

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2018-11-20 17:53:08.855155197 +0000
+++ 0058-net-virtio-user-fix-memory-hotplug-support-in-vhost-.patch	2018-11-20 17:53:07.000000000 +0000
@@ -1,15 +1,16 @@
-From 757286542560ab7f326ae71f5ef8d83050ee5646 Mon Sep 17 00:00:00 2001
+From 4a4c3a7150f1fb714a7057e44672330c997d3d1b Mon Sep 17 00:00:00 2001
 From: Tiwei Bie <tiwei.bie at intel.com>
 Date: Wed, 5 Sep 2018 12:28:52 +0800
 Subject: [PATCH] net/virtio-user: fix memory hotplug support in vhost-kernel
 
+[ upstream commit 757286542560ab7f326ae71f5ef8d83050ee5646 ]
+
 It's possible to have much more hugepage backed memory regions
 than what vhost-kernel supports due to the memory hotplug, which
 may cause problems. A better solution is to have the virtio-user
 pass all the memory ranges reserved by DPDK to vhost-kernel.
 
 Fixes: 12ecb2f63b12 ("net/virtio-user: support memory hotplug")
-Cc: stable at dpdk.org
 
 Signed-off-by: Tiwei Bie <tiwei.bie at intel.com>
 Reviewed-by: Maxime Coquelin <maxime.coquelin at redhat.com>