* [PATCH net-next v5 0/5] remove page frag implementation in vhost_net
@ 2024-02-05 12:45 Yunsheng Lin
2024-02-05 12:45 ` [PATCH net-next v5 1/5] mm/page_alloc: modify page_frag_alloc_align() to accept align as an argument Yunsheng Lin
` (4 more replies)
0 siblings, 5 replies; 8+ messages in thread
From: Yunsheng Lin @ 2024-02-05 12:45 UTC (permalink / raw)
To: davem, kuba, pabeni
Cc: netdev, linux-kernel, Yunsheng Lin, Matthias Brugger,
AngeloGioacchino Del Regno, Alexei Starovoitov, Daniel Borkmann,
Jesper Dangaard Brouer, John Fastabend, linux-arm-kernel,
linux-mediatek, bpf
Currently there are three implementations for page frag:
1. mm/page_alloc.c: net stack seems to be using it in the
rx part with 'struct page_frag_cache' and the main API
being page_frag_alloc_align().
2. net/core/sock.c: net stack seems to be using it in the
tx part with 'struct page_frag' and the main API being
skb_page_frag_refill().
3. drivers/vhost/net.c: vhost seems to be using it to build
xdp frame, and it's implementation seems to be a mix of
the above two.
This patchset tries to unfiy the page frag implementation a
little bit by unifying gfp bit for order 3 page allocation
and replacing page frag implementation in vhost.c with the
one in page_alloc.c.
After this patchset, we are not only able to unify the page
frag implementation a little, but also able to have about
0.5% performance boost testing by using the vhost_net_test
introduced in the last patch.
Before this patchset:
Performance counter stats for './vhost_net_test' (10 runs):
305325.78 msec task-clock # 1.738 CPUs utilized ( +- 0.12% )
1048668 context-switches # 3.435 K/sec ( +- 0.00% )
11 cpu-migrations # 0.036 /sec ( +- 17.64% )
33 page-faults # 0.108 /sec ( +- 0.49% )
244651819491 cycles # 0.801 GHz ( +- 0.43% ) (64)
64714638024 stalled-cycles-frontend # 26.45% frontend cycles idle ( +- 2.19% ) (67)
30774313491 stalled-cycles-backend # 12.58% backend cycles idle ( +- 7.68% ) (70)
201749748680 instructions # 0.82 insn per cycle
# 0.32 stalled cycles per insn ( +- 0.41% ) (66.76%)
65494787909 branches # 214.508 M/sec ( +- 0.35% ) (64)
4284111313 branch-misses # 6.54% of all branches ( +- 0.45% ) (66)
175.699 +- 0.189 seconds time elapsed ( +- 0.11% )
After this patchset:
Performance counter stats for './vhost_net_test' (10 runs):
303974.38 msec task-clock # 1.739 CPUs utilized ( +- 0.14% )
1048807 context-switches # 3.450 K/sec ( +- 0.00% )
14 cpu-migrations # 0.046 /sec ( +- 12.86% )
33 page-faults # 0.109 /sec ( +- 0.46% )
251289376347 cycles # 0.827 GHz ( +- 0.32% ) (60)
67885175415 stalled-cycles-frontend # 27.01% frontend cycles idle ( +- 0.48% ) (63)
27809282600 stalled-cycles-backend # 11.07% backend cycles idle ( +- 0.36% ) (71)
195543234672 instructions # 0.78 insn per cycle
# 0.35 stalled cycles per insn ( +- 0.29% ) (69.04%)
62423183552 branches # 205.357 M/sec ( +- 0.48% ) (67)
4135666632 branch-misses # 6.63% of all branches ( +- 0.63% ) (67)
174.764 +- 0.214 seconds time elapsed ( +- 0.12% )
Changelog:
V5: Address the comment from jason in vhost_net_test.c and the
comment about leaving out the gfp change for page frag in
sock.c as suggested by Paolo.
V4: Resend based on latest net-next branch.
V3:
1. Add __page_frag_alloc_align() which is passed with the align mask
the original function expected as suggested by Alexander.
2. Drop patch 3 in v2 suggested by Alexander.
3. Reorder patch 4 & 5 in v2 suggested by Alexander.
Note that placing this gfp flags handing for order 3 page in an inline
function is not considered, as we may be able to unify the page_frag
and page_frag_cache handling.
V2: Change 'xor'd' to 'masked off', add vhost tx testing for
vhost_net_test.
V1: Fix some typo, drop RFC tag and rebase on latest net-next.
Yunsheng Lin (5):
mm/page_alloc: modify page_frag_alloc_align() to accept align as an
argument
page_frag: unify gfp bits for order 3 page allocation
net: introduce page_frag_cache_drain()
vhost/net: remove vhost_net_page_frag_refill()
tools: virtio: introduce vhost_net_test
drivers/net/ethernet/google/gve/gve_main.c | 11 +-
drivers/net/ethernet/mediatek/mtk_wed_wo.c | 17 +-
drivers/nvme/host/tcp.c | 7 +-
drivers/nvme/target/tcp.c | 4 +-
drivers/vhost/net.c | 91 ++--
include/linux/gfp.h | 16 +-
mm/page_alloc.c | 22 +-
net/core/skbuff.c | 9 +-
tools/virtio/.gitignore | 1 +
tools/virtio/Makefile | 8 +-
tools/virtio/linux/virtio_config.h | 4 +
tools/virtio/vhost_net_test.c | 536 +++++++++++++++++++++
12 files changed, 613 insertions(+), 113 deletions(-)
create mode 100644 tools/virtio/vhost_net_test.c
--
2.33.0
^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH net-next v5 1/5] mm/page_alloc: modify page_frag_alloc_align() to accept align as an argument
2024-02-05 12:45 [PATCH net-next v5 0/5] remove page frag implementation in vhost_net Yunsheng Lin
@ 2024-02-05 12:45 ` Yunsheng Lin
2024-02-05 12:45 ` [PATCH net-next v5 2/5] page_frag: unify gfp bits for order 3 page allocation Yunsheng Lin
` (3 subsequent siblings)
4 siblings, 0 replies; 8+ messages in thread
From: Yunsheng Lin @ 2024-02-05 12:45 UTC (permalink / raw)
To: davem, kuba, pabeni
Cc: netdev, linux-kernel, Yunsheng Lin, Alexander Duyck,
Andrew Morton, Eric Dumazet, linux-mm
napi_alloc_frag_align() and netdev_alloc_frag_align() accept
align as an argument, and they are thin wrappers around the
__napi_alloc_frag_align() and __netdev_alloc_frag_align() APIs
doing the alignment checking and align mask conversion, in order
to call page_frag_alloc_align() directly. The intention here is
to keep the alignment checking and the alignmask conversion in
in-line wrapper to avoid those kind of operations during execution
time since it can usually be handled during compile time.
We are going to use page_frag_alloc_align() in vhost_net.c, it
need the same kind of alignment checking and alignmask conversion,
so split up page_frag_alloc_align into an inline wrapper doing the
above operation, and add __page_frag_alloc_align() which is passed
with the align mask the original function expected as suggested by
Alexander.
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
CC: Alexander Duyck <alexander.duyck@gmail.com>
---
include/linux/gfp.h | 15 +++++++++++----
mm/page_alloc.c | 8 ++++----
net/core/skbuff.c | 9 ++++++---
3 files changed, 21 insertions(+), 11 deletions(-)
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index de292a007138..28aea17fa59b 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -312,14 +312,21 @@ extern void free_pages(unsigned long addr, unsigned int order);
struct page_frag_cache;
extern void __page_frag_cache_drain(struct page *page, unsigned int count);
-extern void *page_frag_alloc_align(struct page_frag_cache *nc,
- unsigned int fragsz, gfp_t gfp_mask,
- unsigned int align_mask);
+void *__page_frag_alloc_align(struct page_frag_cache *nc, unsigned int fragsz,
+ gfp_t gfp_mask, unsigned int align_mask);
+
+static inline void *page_frag_alloc_align(struct page_frag_cache *nc,
+ unsigned int fragsz, gfp_t gfp_mask,
+ unsigned int align)
+{
+ WARN_ON_ONCE(!is_power_of_2(align));
+ return __page_frag_alloc_align(nc, fragsz, gfp_mask, -align);
+}
static inline void *page_frag_alloc(struct page_frag_cache *nc,
unsigned int fragsz, gfp_t gfp_mask)
{
- return page_frag_alloc_align(nc, fragsz, gfp_mask, ~0u);
+ return __page_frag_alloc_align(nc, fragsz, gfp_mask, ~0u);
}
extern void page_frag_free(void *addr);
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 150d4f23b010..c0f7e67c4250 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -4708,9 +4708,9 @@ void __page_frag_cache_drain(struct page *page, unsigned int count)
}
EXPORT_SYMBOL(__page_frag_cache_drain);
-void *page_frag_alloc_align(struct page_frag_cache *nc,
- unsigned int fragsz, gfp_t gfp_mask,
- unsigned int align_mask)
+void *__page_frag_alloc_align(struct page_frag_cache *nc,
+ unsigned int fragsz, gfp_t gfp_mask,
+ unsigned int align_mask)
{
unsigned int size = PAGE_SIZE;
struct page *page;
@@ -4779,7 +4779,7 @@ void *page_frag_alloc_align(struct page_frag_cache *nc,
return nc->va + offset;
}
-EXPORT_SYMBOL(page_frag_alloc_align);
+EXPORT_SYMBOL(__page_frag_alloc_align);
/*
* Frees a page fragment allocated out of either a compound or order 0 page.
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index edbbef563d4d..5b858128463f 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -297,7 +297,8 @@ void *__napi_alloc_frag_align(unsigned int fragsz, unsigned int align_mask)
fragsz = SKB_DATA_ALIGN(fragsz);
- return page_frag_alloc_align(&nc->page, fragsz, GFP_ATOMIC, align_mask);
+ return __page_frag_alloc_align(&nc->page, fragsz, GFP_ATOMIC,
+ align_mask);
}
EXPORT_SYMBOL(__napi_alloc_frag_align);
@@ -309,13 +310,15 @@ void *__netdev_alloc_frag_align(unsigned int fragsz, unsigned int align_mask)
if (in_hardirq() || irqs_disabled()) {
struct page_frag_cache *nc = this_cpu_ptr(&netdev_alloc_cache);
- data = page_frag_alloc_align(nc, fragsz, GFP_ATOMIC, align_mask);
+ data = __page_frag_alloc_align(nc, fragsz, GFP_ATOMIC,
+ align_mask);
} else {
struct napi_alloc_cache *nc;
local_bh_disable();
nc = this_cpu_ptr(&napi_alloc_cache);
- data = page_frag_alloc_align(&nc->page, fragsz, GFP_ATOMIC, align_mask);
+ data = __page_frag_alloc_align(&nc->page, fragsz, GFP_ATOMIC,
+ align_mask);
local_bh_enable();
}
return data;
--
2.33.0
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH net-next v5 2/5] page_frag: unify gfp bits for order 3 page allocation
2024-02-05 12:45 [PATCH net-next v5 0/5] remove page frag implementation in vhost_net Yunsheng Lin
2024-02-05 12:45 ` [PATCH net-next v5 1/5] mm/page_alloc: modify page_frag_alloc_align() to accept align as an argument Yunsheng Lin
@ 2024-02-05 12:45 ` Yunsheng Lin
2024-02-05 12:45 ` [PATCH net-next v5 3/5] net: introduce page_frag_cache_drain() Yunsheng Lin
` (2 subsequent siblings)
4 siblings, 0 replies; 8+ messages in thread
From: Yunsheng Lin @ 2024-02-05 12:45 UTC (permalink / raw)
To: davem, kuba, pabeni
Cc: netdev, linux-kernel, Yunsheng Lin, Alexander Duyck,
Alexander Duyck, Michael S. Tsirkin, Jason Wang, Andrew Morton,
kvm, virtualization, linux-mm
Currently there seems to be three page frag implementations
which all try to allocate order 3 page, if that fails, it
then fail back to allocate order 0 page, and each of them
all allow order 3 page allocation to fail under certain
condition by using specific gfp bits.
The gfp bits for order 3 page allocation are different
between different implementation, __GFP_NOMEMALLOC is
or'd to forbid access to emergency reserves memory for
__page_frag_cache_refill(), but it is not or'd in other
implementions, __GFP_DIRECT_RECLAIM is masked off to avoid
direct reclaim in vhost_net_page_frag_refill(), but it is
not masked off in __page_frag_cache_refill().
This patch unifies the gfp bits used between different
implementions by or'ing __GFP_NOMEMALLOC and masking off
__GFP_DIRECT_RECLAIM for order 3 page allocation to avoid
possible pressure for mm.
Leave the gfp unifying for page frag implementation in sock.c
for now as suggested by Paolo Abeni.
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
CC: Alexander Duyck <alexander.duyck@gmail.com>
---
drivers/vhost/net.c | 2 +-
mm/page_alloc.c | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index f2ed7167c848..e574e21cc0ca 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -670,7 +670,7 @@ static bool vhost_net_page_frag_refill(struct vhost_net *net, unsigned int sz,
/* Avoid direct reclaim but allow kswapd to wake */
pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
__GFP_COMP | __GFP_NOWARN |
- __GFP_NORETRY,
+ __GFP_NORETRY | __GFP_NOMEMALLOC,
SKB_FRAG_PAGE_ORDER);
if (likely(pfrag->page)) {
pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index c0f7e67c4250..636145c29f70 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -4685,8 +4685,8 @@ static struct page *__page_frag_cache_refill(struct page_frag_cache *nc,
gfp_t gfp = gfp_mask;
#if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE)
- gfp_mask |= __GFP_COMP | __GFP_NOWARN | __GFP_NORETRY |
- __GFP_NOMEMALLOC;
+ gfp_mask = (gfp_mask & ~__GFP_DIRECT_RECLAIM) | __GFP_COMP |
+ __GFP_NOWARN | __GFP_NORETRY | __GFP_NOMEMALLOC;
page = alloc_pages_node(NUMA_NO_NODE, gfp_mask,
PAGE_FRAG_CACHE_MAX_ORDER);
nc->size = page ? PAGE_FRAG_CACHE_MAX_SIZE : PAGE_SIZE;
--
2.33.0
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH net-next v5 3/5] net: introduce page_frag_cache_drain()
2024-02-05 12:45 [PATCH net-next v5 0/5] remove page frag implementation in vhost_net Yunsheng Lin
2024-02-05 12:45 ` [PATCH net-next v5 1/5] mm/page_alloc: modify page_frag_alloc_align() to accept align as an argument Yunsheng Lin
2024-02-05 12:45 ` [PATCH net-next v5 2/5] page_frag: unify gfp bits for order 3 page allocation Yunsheng Lin
@ 2024-02-05 12:45 ` Yunsheng Lin
2024-02-05 12:45 ` [PATCH net-next v5 4/5] vhost/net: remove vhost_net_page_frag_refill() Yunsheng Lin
2024-02-05 12:45 ` [PATCH net-next v5 5/5] tools: virtio: introduce vhost_net_test Yunsheng Lin
4 siblings, 0 replies; 8+ messages in thread
From: Yunsheng Lin @ 2024-02-05 12:45 UTC (permalink / raw)
To: davem, kuba, pabeni
Cc: netdev, linux-kernel, Yunsheng Lin, Jason Wang, Alexander Duyck,
Jeroen de Borst, Praveen Kaligineedi, Shailend Chand,
Eric Dumazet, Felix Fietkau, Sean Wang, Mark Lee,
Lorenzo Bianconi, Matthias Brugger, AngeloGioacchino Del Regno,
Keith Busch, Jens Axboe, Christoph Hellwig, Sagi Grimberg,
Chaitanya Kulkarni, Andrew Morton, linux-arm-kernel,
linux-mediatek, linux-nvme, linux-mm
When draining a page_frag_cache, most user are doing
the similar steps, so introduce an API to avoid code
duplication.
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
---
drivers/net/ethernet/google/gve/gve_main.c | 11 ++---------
drivers/net/ethernet/mediatek/mtk_wed_wo.c | 17 ++---------------
drivers/nvme/host/tcp.c | 7 +------
drivers/nvme/target/tcp.c | 4 +---
include/linux/gfp.h | 1 +
mm/page_alloc.c | 10 ++++++++++
6 files changed, 17 insertions(+), 33 deletions(-)
diff --git a/drivers/net/ethernet/google/gve/gve_main.c b/drivers/net/ethernet/google/gve/gve_main.c
index db6d9ae7cd78..dec6458bb8d7 100644
--- a/drivers/net/ethernet/google/gve/gve_main.c
+++ b/drivers/net/ethernet/google/gve/gve_main.c
@@ -1276,17 +1276,10 @@ static void gve_unreg_xdp_info(struct gve_priv *priv)
static void gve_drain_page_cache(struct gve_priv *priv)
{
- struct page_frag_cache *nc;
int i;
- for (i = 0; i < priv->rx_cfg.num_queues; i++) {
- nc = &priv->rx[i].page_cache;
- if (nc->va) {
- __page_frag_cache_drain(virt_to_page(nc->va),
- nc->pagecnt_bias);
- nc->va = NULL;
- }
- }
+ for (i = 0; i < priv->rx_cfg.num_queues; i++)
+ page_frag_cache_drain(&priv->rx[i].page_cache);
}
static void gve_qpls_get_curr_alloc_cfg(struct gve_priv *priv,
diff --git a/drivers/net/ethernet/mediatek/mtk_wed_wo.c b/drivers/net/ethernet/mediatek/mtk_wed_wo.c
index d58b07e7e123..7063c78bd35f 100644
--- a/drivers/net/ethernet/mediatek/mtk_wed_wo.c
+++ b/drivers/net/ethernet/mediatek/mtk_wed_wo.c
@@ -286,7 +286,6 @@ mtk_wed_wo_queue_free(struct mtk_wed_wo *wo, struct mtk_wed_wo_queue *q)
static void
mtk_wed_wo_queue_tx_clean(struct mtk_wed_wo *wo, struct mtk_wed_wo_queue *q)
{
- struct page *page;
int i;
for (i = 0; i < q->n_desc; i++) {
@@ -301,19 +300,12 @@ mtk_wed_wo_queue_tx_clean(struct mtk_wed_wo *wo, struct mtk_wed_wo_queue *q)
entry->buf = NULL;
}
- if (!q->cache.va)
- return;
-
- page = virt_to_page(q->cache.va);
- __page_frag_cache_drain(page, q->cache.pagecnt_bias);
- memset(&q->cache, 0, sizeof(q->cache));
+ page_frag_cache_drain(&q->cache);
}
static void
mtk_wed_wo_queue_rx_clean(struct mtk_wed_wo *wo, struct mtk_wed_wo_queue *q)
{
- struct page *page;
-
for (;;) {
void *buf = mtk_wed_wo_dequeue(wo, q, NULL, true);
@@ -323,12 +315,7 @@ mtk_wed_wo_queue_rx_clean(struct mtk_wed_wo *wo, struct mtk_wed_wo_queue *q)
skb_free_frag(buf);
}
- if (!q->cache.va)
- return;
-
- page = virt_to_page(q->cache.va);
- __page_frag_cache_drain(page, q->cache.pagecnt_bias);
- memset(&q->cache, 0, sizeof(q->cache));
+ page_frag_cache_drain(&q->cache);
}
static void
diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
index d058d990532b..22e1fb9c9c0f 100644
--- a/drivers/nvme/host/tcp.c
+++ b/drivers/nvme/host/tcp.c
@@ -1344,7 +1344,6 @@ static int nvme_tcp_alloc_async_req(struct nvme_tcp_ctrl *ctrl)
static void nvme_tcp_free_queue(struct nvme_ctrl *nctrl, int qid)
{
- struct page *page;
struct nvme_tcp_ctrl *ctrl = to_tcp_ctrl(nctrl);
struct nvme_tcp_queue *queue = &ctrl->queues[qid];
unsigned int noreclaim_flag;
@@ -1355,11 +1354,7 @@ static void nvme_tcp_free_queue(struct nvme_ctrl *nctrl, int qid)
if (queue->hdr_digest || queue->data_digest)
nvme_tcp_free_crypto(queue);
- if (queue->pf_cache.va) {
- page = virt_to_head_page(queue->pf_cache.va);
- __page_frag_cache_drain(page, queue->pf_cache.pagecnt_bias);
- queue->pf_cache.va = NULL;
- }
+ page_frag_cache_drain(&queue->pf_cache);
noreclaim_flag = memalloc_noreclaim_save();
/* ->sock will be released by fput() */
diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c
index 6a1e6bb80062..56224dc59f17 100644
--- a/drivers/nvme/target/tcp.c
+++ b/drivers/nvme/target/tcp.c
@@ -1591,7 +1591,6 @@ static void nvmet_tcp_free_cmd_data_in_buffers(struct nvmet_tcp_queue *queue)
static void nvmet_tcp_release_queue_work(struct work_struct *w)
{
- struct page *page;
struct nvmet_tcp_queue *queue =
container_of(w, struct nvmet_tcp_queue, release_work);
@@ -1615,8 +1614,7 @@ static void nvmet_tcp_release_queue_work(struct work_struct *w)
if (queue->hdr_digest || queue->data_digest)
nvmet_tcp_free_crypto(queue);
ida_free(&nvmet_tcp_queue_ida, queue->idx);
- page = virt_to_head_page(queue->pf_cache.va);
- __page_frag_cache_drain(page, queue->pf_cache.pagecnt_bias);
+ page_frag_cache_drain(&queue->pf_cache);
kfree(queue);
}
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 28aea17fa59b..6cef1c241180 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -311,6 +311,7 @@ extern void __free_pages(struct page *page, unsigned int order);
extern void free_pages(unsigned long addr, unsigned int order);
struct page_frag_cache;
+void page_frag_cache_drain(struct page_frag_cache *nc);
extern void __page_frag_cache_drain(struct page *page, unsigned int count);
void *__page_frag_alloc_align(struct page_frag_cache *nc, unsigned int fragsz,
gfp_t gfp_mask, unsigned int align_mask);
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 636145c29f70..06aa1ebbd21c 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -4699,6 +4699,16 @@ static struct page *__page_frag_cache_refill(struct page_frag_cache *nc,
return page;
}
+void page_frag_cache_drain(struct page_frag_cache *nc)
+{
+ if (!nc->va)
+ return;
+
+ __page_frag_cache_drain(virt_to_head_page(nc->va), nc->pagecnt_bias);
+ nc->va = NULL;
+}
+EXPORT_SYMBOL(page_frag_cache_drain);
+
void __page_frag_cache_drain(struct page *page, unsigned int count)
{
VM_BUG_ON_PAGE(page_ref_count(page) == 0, page);
--
2.33.0
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH net-next v5 4/5] vhost/net: remove vhost_net_page_frag_refill()
2024-02-05 12:45 [PATCH net-next v5 0/5] remove page frag implementation in vhost_net Yunsheng Lin
` (2 preceding siblings ...)
2024-02-05 12:45 ` [PATCH net-next v5 3/5] net: introduce page_frag_cache_drain() Yunsheng Lin
@ 2024-02-05 12:45 ` Yunsheng Lin
2024-02-05 12:45 ` [PATCH net-next v5 5/5] tools: virtio: introduce vhost_net_test Yunsheng Lin
4 siblings, 0 replies; 8+ messages in thread
From: Yunsheng Lin @ 2024-02-05 12:45 UTC (permalink / raw)
To: davem, kuba, pabeni
Cc: netdev, linux-kernel, Yunsheng Lin, Jason Wang,
Michael S. Tsirkin, Alexei Starovoitov, Daniel Borkmann,
Jesper Dangaard Brouer, John Fastabend, kvm, virtualization, bpf
The page frag in vhost_net_page_frag_refill() uses the
'struct page_frag' from skb_page_frag_refill(), but it's
implementation is similar to page_frag_alloc_align() now.
This patch removes vhost_net_page_frag_refill() by using
'struct page_frag_cache' instead of 'struct page_frag',
and allocating frag using page_frag_alloc_align().
The added benefit is that not only unifying the page frag
implementation a little, but also having about 0.5% performance
boost testing by using the vhost_net_test introduced in the
last patch.
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Acked-by: Jason Wang <jasowang@redhat.com>
---
drivers/vhost/net.c | 91 ++++++++++++++-------------------------------
1 file changed, 27 insertions(+), 64 deletions(-)
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index e574e21cc0ca..4b2fcb228a0a 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -141,10 +141,8 @@ struct vhost_net {
unsigned tx_zcopy_err;
/* Flush in progress. Protected by tx vq lock. */
bool tx_flush;
- /* Private page frag */
- struct page_frag page_frag;
- /* Refcount bias of page frag */
- int refcnt_bias;
+ /* Private page frag cache */
+ struct page_frag_cache pf_cache;
};
static unsigned vhost_net_zcopy_mask __read_mostly;
@@ -655,41 +653,6 @@ static bool tx_can_batch(struct vhost_virtqueue *vq, size_t total_len)
!vhost_vq_avail_empty(vq->dev, vq);
}
-static bool vhost_net_page_frag_refill(struct vhost_net *net, unsigned int sz,
- struct page_frag *pfrag, gfp_t gfp)
-{
- if (pfrag->page) {
- if (pfrag->offset + sz <= pfrag->size)
- return true;
- __page_frag_cache_drain(pfrag->page, net->refcnt_bias);
- }
-
- pfrag->offset = 0;
- net->refcnt_bias = 0;
- if (SKB_FRAG_PAGE_ORDER) {
- /* Avoid direct reclaim but allow kswapd to wake */
- pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
- __GFP_COMP | __GFP_NOWARN |
- __GFP_NORETRY | __GFP_NOMEMALLOC,
- SKB_FRAG_PAGE_ORDER);
- if (likely(pfrag->page)) {
- pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
- goto done;
- }
- }
- pfrag->page = alloc_page(gfp);
- if (likely(pfrag->page)) {
- pfrag->size = PAGE_SIZE;
- goto done;
- }
- return false;
-
-done:
- net->refcnt_bias = USHRT_MAX;
- page_ref_add(pfrag->page, USHRT_MAX - 1);
- return true;
-}
-
#define VHOST_NET_RX_PAD (NET_IP_ALIGN + NET_SKB_PAD)
static int vhost_net_build_xdp(struct vhost_net_virtqueue *nvq,
@@ -699,7 +662,6 @@ static int vhost_net_build_xdp(struct vhost_net_virtqueue *nvq,
struct vhost_net *net = container_of(vq->dev, struct vhost_net,
dev);
struct socket *sock = vhost_vq_get_backend(vq);
- struct page_frag *alloc_frag = &net->page_frag;
struct virtio_net_hdr *gso;
struct xdp_buff *xdp = &nvq->xdp[nvq->batched_xdp];
struct tun_xdp_hdr *hdr;
@@ -710,6 +672,7 @@ static int vhost_net_build_xdp(struct vhost_net_virtqueue *nvq,
int sock_hlen = nvq->sock_hlen;
void *buf;
int copied;
+ int ret;
if (unlikely(len < nvq->sock_hlen))
return -EFAULT;
@@ -719,18 +682,17 @@ static int vhost_net_build_xdp(struct vhost_net_virtqueue *nvq,
return -ENOSPC;
buflen += SKB_DATA_ALIGN(len + pad);
- alloc_frag->offset = ALIGN((u64)alloc_frag->offset, SMP_CACHE_BYTES);
- if (unlikely(!vhost_net_page_frag_refill(net, buflen,
- alloc_frag, GFP_KERNEL)))
+ buf = page_frag_alloc_align(&net->pf_cache, buflen, GFP_KERNEL,
+ SMP_CACHE_BYTES);
+ if (unlikely(!buf))
return -ENOMEM;
- buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
- copied = copy_page_from_iter(alloc_frag->page,
- alloc_frag->offset +
- offsetof(struct tun_xdp_hdr, gso),
- sock_hlen, from);
- if (copied != sock_hlen)
- return -EFAULT;
+ copied = copy_from_iter(buf + offsetof(struct tun_xdp_hdr, gso),
+ sock_hlen, from);
+ if (copied != sock_hlen) {
+ ret = -EFAULT;
+ goto err;
+ }
hdr = buf;
gso = &hdr->gso;
@@ -743,27 +705,30 @@ static int vhost_net_build_xdp(struct vhost_net_virtqueue *nvq,
vhost16_to_cpu(vq, gso->csum_start) +
vhost16_to_cpu(vq, gso->csum_offset) + 2);
- if (vhost16_to_cpu(vq, gso->hdr_len) > len)
- return -EINVAL;
+ if (vhost16_to_cpu(vq, gso->hdr_len) > len) {
+ ret = -EINVAL;
+ goto err;
+ }
}
len -= sock_hlen;
- copied = copy_page_from_iter(alloc_frag->page,
- alloc_frag->offset + pad,
- len, from);
- if (copied != len)
- return -EFAULT;
+ copied = copy_from_iter(buf + pad, len, from);
+ if (copied != len) {
+ ret = -EFAULT;
+ goto err;
+ }
xdp_init_buff(xdp, buflen, NULL);
xdp_prepare_buff(xdp, buf, pad, len, true);
hdr->buflen = buflen;
- --net->refcnt_bias;
- alloc_frag->offset += buflen;
-
++nvq->batched_xdp;
return 0;
+
+err:
+ page_frag_free(buf);
+ return ret;
}
static void handle_tx_copy(struct vhost_net *net, struct socket *sock)
@@ -1353,8 +1318,7 @@ static int vhost_net_open(struct inode *inode, struct file *f)
vqs[VHOST_NET_VQ_RX]);
f->private_data = n;
- n->page_frag.page = NULL;
- n->refcnt_bias = 0;
+ n->pf_cache.va = NULL;
return 0;
}
@@ -1422,8 +1386,7 @@ static int vhost_net_release(struct inode *inode, struct file *f)
kfree(n->vqs[VHOST_NET_VQ_RX].rxq.queue);
kfree(n->vqs[VHOST_NET_VQ_TX].xdp);
kfree(n->dev.vqs);
- if (n->page_frag.page)
- __page_frag_cache_drain(n->page_frag.page, n->refcnt_bias);
+ page_frag_cache_drain(&n->pf_cache);
kvfree(n);
return 0;
}
--
2.33.0
^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH net-next v5 5/5] tools: virtio: introduce vhost_net_test
2024-02-05 12:45 [PATCH net-next v5 0/5] remove page frag implementation in vhost_net Yunsheng Lin
` (3 preceding siblings ...)
2024-02-05 12:45 ` [PATCH net-next v5 4/5] vhost/net: remove vhost_net_page_frag_refill() Yunsheng Lin
@ 2024-02-05 12:45 ` Yunsheng Lin
2024-02-06 3:08 ` Jason Wang
4 siblings, 1 reply; 8+ messages in thread
From: Yunsheng Lin @ 2024-02-05 12:45 UTC (permalink / raw)
To: davem, kuba, pabeni
Cc: netdev, linux-kernel, Yunsheng Lin, Michael S. Tsirkin,
Jason Wang, Xuan Zhuo, virtualization
introduce vhost_net_test for both vhost_net tx and rx basing
on virtio_test to test vhost_net changing in the kernel.
Steps for vhost_net tx testing:
1. Prepare a out buf.
2. Kick the vhost_net to do tx processing.
3. Do the receiving in the tun side.
4. verify the data received by tun is correct.
Steps for vhost_net rx testing:
1. Prepare a in buf.
2. Do the sending in the tun side.
3. Kick the vhost_net to do rx processing.
4. verify the data received by vhost_net is correct.
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
---
tools/virtio/.gitignore | 1 +
tools/virtio/Makefile | 8 +-
tools/virtio/linux/virtio_config.h | 4 +
tools/virtio/vhost_net_test.c | 536 +++++++++++++++++++++++++++++
4 files changed, 546 insertions(+), 3 deletions(-)
create mode 100644 tools/virtio/vhost_net_test.c
diff --git a/tools/virtio/.gitignore b/tools/virtio/.gitignore
index 9934d48d9a55..7e47b281c442 100644
--- a/tools/virtio/.gitignore
+++ b/tools/virtio/.gitignore
@@ -1,5 +1,6 @@
# SPDX-License-Identifier: GPL-2.0-only
*.d
virtio_test
+vhost_net_test
vringh_test
virtio-trace/trace-agent
diff --git a/tools/virtio/Makefile b/tools/virtio/Makefile
index d128925980e0..e25e99c1c3b7 100644
--- a/tools/virtio/Makefile
+++ b/tools/virtio/Makefile
@@ -1,8 +1,9 @@
# SPDX-License-Identifier: GPL-2.0
all: test mod
-test: virtio_test vringh_test
+test: virtio_test vringh_test vhost_net_test
virtio_test: virtio_ring.o virtio_test.o
vringh_test: vringh_test.o vringh.o virtio_ring.o
+vhost_net_test: virtio_ring.o vhost_net_test.o
try-run = $(shell set -e; \
if ($(1)) >/dev/null 2>&1; \
@@ -49,6 +50,7 @@ oot-clean: OOT_BUILD+=clean
.PHONY: all test mod clean vhost oot oot-clean oot-build
clean:
- ${RM} *.o vringh_test virtio_test vhost_test/*.o vhost_test/.*.cmd \
- vhost_test/Module.symvers vhost_test/modules.order *.d
+ ${RM} *.o vringh_test virtio_test vhost_net_test vhost_test/*.o \
+ vhost_test/.*.cmd vhost_test/Module.symvers \
+ vhost_test/modules.order *.d
-include *.d
diff --git a/tools/virtio/linux/virtio_config.h b/tools/virtio/linux/virtio_config.h
index 2a8a70e2a950..42a564f22f2d 100644
--- a/tools/virtio/linux/virtio_config.h
+++ b/tools/virtio/linux/virtio_config.h
@@ -1,4 +1,6 @@
/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef LINUX_VIRTIO_CONFIG_H
+#define LINUX_VIRTIO_CONFIG_H
#include <linux/virtio_byteorder.h>
#include <linux/virtio.h>
#include <uapi/linux/virtio_config.h>
@@ -95,3 +97,5 @@ static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val)
{
return __cpu_to_virtio64(virtio_is_little_endian(vdev), val);
}
+
+#endif
diff --git a/tools/virtio/vhost_net_test.c b/tools/virtio/vhost_net_test.c
new file mode 100644
index 000000000000..6c41204e6707
--- /dev/null
+++ b/tools/virtio/vhost_net_test.c
@@ -0,0 +1,536 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <getopt.h>
+#include <limits.h>
+#include <string.h>
+#include <poll.h>
+#include <sys/eventfd.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <fcntl.h>
+#include <stdbool.h>
+#include <linux/vhost.h>
+#include <linux/if.h>
+#include <linux/if_tun.h>
+#include <linux/in.h>
+#include <linux/if_packet.h>
+#include <linux/virtio_net.h>
+#include <netinet/ether.h>
+
+#define HDR_LEN sizeof(struct virtio_net_hdr_mrg_rxbuf)
+#define TEST_BUF_LEN 256
+#define TEST_PTYPE ETH_P_LOOPBACK
+#define DESC_NUM 256
+
+/* Used by implementation of kmalloc() in tools/virtio/linux/kernel.h */
+void *__kmalloc_fake, *__kfree_ignore_start, *__kfree_ignore_end;
+
+struct vq_info {
+ int kick;
+ int call;
+ int idx;
+ long started;
+ long completed;
+ struct pollfd fds;
+ void *ring;
+ /* copy used for control */
+ struct vring vring;
+ struct virtqueue *vq;
+};
+
+struct vdev_info {
+ struct virtio_device vdev;
+ int control;
+ struct vq_info vqs[2];
+ int nvqs;
+ void *buf;
+ size_t buf_size;
+ char *test_buf;
+ char *res_buf;
+ struct vhost_memory *mem;
+ int sock;
+ int ifindex;
+ unsigned char mac[ETHER_ADDR_LEN];
+};
+
+static int tun_alloc(struct vdev_info *dev, char *tun_name)
+{
+ struct ifreq ifr;
+ int len = HDR_LEN;
+ int fd, e;
+
+ fd = open("/dev/net/tun", O_RDWR);
+ if (fd < 0) {
+ perror("Cannot open /dev/net/tun");
+ return fd;
+ }
+
+ memset(&ifr, 0, sizeof(ifr));
+
+ ifr.ifr_flags = IFF_TAP | IFF_NO_PI | IFF_VNET_HDR;
+ strncpy(ifr.ifr_name, tun_name, IFNAMSIZ);
+
+ e = ioctl(fd, TUNSETIFF, &ifr);
+ if (e < 0) {
+ perror("ioctl[TUNSETIFF]");
+ close(fd);
+ return e;
+ }
+
+ e = ioctl(fd, TUNSETVNETHDRSZ, &len);
+ if (e < 0) {
+ perror("ioctl[TUNSETVNETHDRSZ]");
+ close(fd);
+ return e;
+ }
+
+ e = ioctl(fd, SIOCGIFHWADDR, &ifr);
+ if (e < 0) {
+ perror("ioctl[SIOCGIFHWADDR]");
+ close(fd);
+ return e;
+ }
+
+ memcpy(dev->mac, &ifr.ifr_hwaddr.sa_data, ETHER_ADDR_LEN);
+ return fd;
+}
+
+static void vdev_create_socket(struct vdev_info *dev, char *tun_name)
+{
+ struct ifreq ifr;
+
+ dev->sock = socket(AF_PACKET, SOCK_RAW, htons(TEST_PTYPE));
+ assert(dev->sock != -1);
+
+ strncpy(ifr.ifr_name, tun_name, IFNAMSIZ);
+ assert(ioctl(dev->sock, SIOCGIFINDEX, &ifr) >= 0);
+
+ dev->ifindex = ifr.ifr_ifindex;
+
+ /* Set the flags that bring the device up */
+ assert(ioctl(dev->sock, SIOCGIFFLAGS, &ifr) >= 0);
+ ifr.ifr_flags |= (IFF_UP | IFF_RUNNING);
+ assert(ioctl(dev->sock, SIOCSIFFLAGS, &ifr) >= 0);
+}
+
+static void vdev_send_packet(struct vdev_info *dev)
+{
+ char *sendbuf = dev->test_buf + HDR_LEN;
+ struct sockaddr_ll saddrll = {0};
+ int sockfd = dev->sock;
+ int ret;
+
+ saddrll.sll_family = PF_PACKET;
+ saddrll.sll_ifindex = dev->ifindex;
+ saddrll.sll_halen = ETH_ALEN;
+ saddrll.sll_protocol = htons(TEST_PTYPE);
+
+ ret = sendto(sockfd, sendbuf, TEST_BUF_LEN, 0,
+ (struct sockaddr *)&saddrll,
+ sizeof(struct sockaddr_ll));
+ assert(ret >= 0);
+}
+
+static bool vq_notify(struct virtqueue *vq)
+{
+ struct vq_info *info = vq->priv;
+ unsigned long long v = 1;
+ int r;
+
+ r = write(info->kick, &v, sizeof(v));
+ assert(r == sizeof(v));
+
+ return true;
+}
+
+static void vhost_vq_setup(struct vdev_info *dev, struct vq_info *info)
+{
+ struct vhost_vring_addr addr = {
+ .index = info->idx,
+ .desc_user_addr = (uint64_t)(unsigned long)info->vring.desc,
+ .avail_user_addr = (uint64_t)(unsigned long)info->vring.avail,
+ .used_user_addr = (uint64_t)(unsigned long)info->vring.used,
+ };
+ struct vhost_vring_state state = { .index = info->idx };
+ struct vhost_vring_file file = { .index = info->idx };
+ int r;
+
+ state.num = info->vring.num;
+ r = ioctl(dev->control, VHOST_SET_VRING_NUM, &state);
+ assert(r >= 0);
+
+ state.num = 0;
+ r = ioctl(dev->control, VHOST_SET_VRING_BASE, &state);
+ assert(r >= 0);
+
+ r = ioctl(dev->control, VHOST_SET_VRING_ADDR, &addr);
+ assert(r >= 0);
+
+ file.fd = info->kick;
+ r = ioctl(dev->control, VHOST_SET_VRING_KICK, &file);
+ assert(r >= 0);
+}
+
+static void vq_reset(struct vq_info *info, int num, struct virtio_device *vdev)
+{
+ if (info->vq)
+ vring_del_virtqueue(info->vq);
+
+ memset(info->ring, 0, vring_size(num, 4096));
+ vring_init(&info->vring, num, info->ring, 4096);
+ info->vq = vring_new_virtqueue(info->idx, num, 4096, vdev, true, false,
+ info->ring, vq_notify, NULL, "test");
+ assert(info->vq);
+ info->vq->priv = info;
+}
+
+static void vq_info_add(struct vdev_info *dev, int idx, int num, int fd)
+{
+ struct vhost_vring_file backend = { .index = idx, .fd = fd };
+ struct vq_info *info = &dev->vqs[idx];
+ int r;
+
+ info->idx = idx;
+ info->kick = eventfd(0, EFD_NONBLOCK);
+ r = posix_memalign(&info->ring, 4096, vring_size(num, 4096));
+ assert(r >= 0);
+ vq_reset(info, num, &dev->vdev);
+ vhost_vq_setup(dev, info);
+
+ r = ioctl(dev->control, VHOST_NET_SET_BACKEND, &backend);
+ assert(!r);
+}
+
+static void vdev_info_init(struct vdev_info *dev, unsigned long long features)
+{
+ struct ether_header *eh;
+ int i, r;
+
+ dev->vdev.features = features;
+ INIT_LIST_HEAD(&dev->vdev.vqs);
+ spin_lock_init(&dev->vdev.vqs_list_lock);
+
+ dev->buf_size = (HDR_LEN + TEST_BUF_LEN) * 2;
+ dev->buf = malloc(dev->buf_size);
+ assert(dev->buf);
+ dev->test_buf = dev->buf;
+ dev->res_buf = dev->test_buf + HDR_LEN + TEST_BUF_LEN;
+
+ memset(dev->test_buf, 0, HDR_LEN + TEST_BUF_LEN);
+ eh = (struct ether_header *)(dev->test_buf + HDR_LEN);
+ eh->ether_type = htons(TEST_PTYPE);
+ memcpy(eh->ether_dhost, dev->mac, ETHER_ADDR_LEN);
+ memcpy(eh->ether_shost, dev->mac, ETHER_ADDR_LEN);
+
+ for (i = sizeof(*eh); i < TEST_BUF_LEN; i++)
+ dev->test_buf[i + HDR_LEN] = (char)i;
+
+ dev->control = open("/dev/vhost-net", O_RDWR);
+ assert(dev->control >= 0);
+
+ r = ioctl(dev->control, VHOST_SET_OWNER, NULL);
+ assert(r >= 0);
+
+ dev->mem = malloc(offsetof(struct vhost_memory, regions) +
+ sizeof(dev->mem->regions[0]));
+ assert(dev->mem);
+ memset(dev->mem, 0, offsetof(struct vhost_memory, regions) +
+ sizeof(dev->mem->regions[0]));
+ dev->mem->nregions = 1;
+ dev->mem->regions[0].guest_phys_addr = (long)dev->buf;
+ dev->mem->regions[0].userspace_addr = (long)dev->buf;
+ dev->mem->regions[0].memory_size = dev->buf_size;
+
+ r = ioctl(dev->control, VHOST_SET_MEM_TABLE, dev->mem);
+ assert(r >= 0);
+
+ r = ioctl(dev->control, VHOST_SET_FEATURES, &features);
+ assert(r >= 0);
+
+ dev->nvqs = 2;
+}
+
+static void wait_for_interrupt(struct vq_info *vq)
+{
+ unsigned long long val;
+
+ poll(&vq->fds, 1, -1);
+
+ if (vq->fds.revents & POLLIN)
+ read(vq->fds.fd, &val, sizeof(val));
+}
+
+static void verify_res_buf(char *res_buf)
+{
+ int i;
+
+ for (i = ETHER_HDR_LEN; i < TEST_BUF_LEN; i++)
+ assert(res_buf[i] == (char)i);
+}
+
+static void run_tx_test(struct vdev_info *dev, struct vq_info *vq,
+ bool delayed, int bufs)
+{
+ long long spurious = 0;
+ struct scatterlist sl;
+ unsigned int len;
+ int r;
+
+ for (;;) {
+ long started_before = vq->started;
+ long completed_before = vq->completed;
+
+ virtqueue_disable_cb(vq->vq);
+ do {
+ while (vq->started < bufs &&
+ (vq->started - vq->completed) < 1) {
+ sg_init_one(&sl, dev->test_buf, HDR_LEN + TEST_BUF_LEN);
+ r = virtqueue_add_outbuf(vq->vq, &sl, 1,
+ dev->test_buf + vq->started,
+ GFP_ATOMIC);
+ if (unlikely(r != 0))
+ break;
+
+ ++vq->started;
+
+ if (unlikely(!virtqueue_kick(vq->vq))) {
+ r = -1;
+ break;
+ }
+ }
+
+ if (vq->started >= bufs)
+ r = -1;
+
+ /* Flush out completed bufs if any */
+ while (virtqueue_get_buf(vq->vq, &len)) {
+ int n;
+
+ n = recvfrom(dev->sock, dev->res_buf, TEST_BUF_LEN, 0, NULL, NULL);
+ assert(n == TEST_BUF_LEN);
+ verify_res_buf(dev->res_buf);
+
+ ++vq->completed;
+ r = 0;
+ }
+ } while (r == 0);
+
+ if (vq->completed == completed_before && vq->started == started_before)
+ ++spurious;
+
+ assert(vq->completed <= bufs);
+ assert(vq->started <= bufs);
+ if (vq->completed == bufs)
+ break;
+
+ if (delayed) {
+ if (virtqueue_enable_cb_delayed(vq->vq))
+ wait_for_interrupt(vq);
+ } else {
+ if (virtqueue_enable_cb(vq->vq))
+ wait_for_interrupt(vq);
+ }
+ }
+ printf("TX spurious wakeups: 0x%llx started=0x%lx completed=0x%lx\n",
+ spurious, vq->started, vq->completed);
+}
+
+static void run_rx_test(struct vdev_info *dev, struct vq_info *vq,
+ bool delayed, int bufs)
+{
+ long long spurious = 0;
+ struct scatterlist sl;
+ unsigned int len;
+ int r;
+
+ for (;;) {
+ long started_before = vq->started;
+ long completed_before = vq->completed;
+
+ do {
+ while (vq->started < bufs &&
+ (vq->started - vq->completed) < 1) {
+ sg_init_one(&sl, dev->res_buf, HDR_LEN + TEST_BUF_LEN);
+
+ r = virtqueue_add_inbuf(vq->vq, &sl, 1,
+ dev->res_buf + vq->started,
+ GFP_ATOMIC);
+ if (unlikely(r != 0))
+ break;
+
+ ++vq->started;
+
+ vdev_send_packet(dev);
+
+ if (unlikely(!virtqueue_kick(vq->vq))) {
+ r = -1;
+ break;
+ }
+ }
+
+ if (vq->started >= bufs)
+ r = -1;
+
+ /* Flush out completed bufs if any */
+ while (virtqueue_get_buf(vq->vq, &len)) {
+ struct ether_header *eh;
+
+ eh = (struct ether_header *)(dev->res_buf + HDR_LEN);
+
+ /* tun netdev is up and running, ignore the
+ * non-TEST_PTYPE packet.
+ */
+ if (eh->ether_type != htons(TEST_PTYPE)) {
+ ++vq->completed;
+ r = 0;
+ continue;
+ }
+
+ assert(len == TEST_BUF_LEN + HDR_LEN);
+ verify_res_buf(dev->res_buf + HDR_LEN);
+
+ ++vq->completed;
+ r = 0;
+ }
+ } while (r == 0);
+
+ if (vq->completed == completed_before && vq->started == started_before)
+ ++spurious;
+
+ assert(vq->completed <= bufs);
+ assert(vq->started <= bufs);
+ if (vq->completed == bufs)
+ break;
+ }
+
+ printf("RX spurious wakeups: 0x%llx started=0x%lx completed=0x%lx\n",
+ spurious, vq->started, vq->completed);
+}
+
+static const char optstring[] = "h";
+static const struct option longopts[] = {
+ {
+ .name = "help",
+ .val = 'h',
+ },
+ {
+ .name = "event-idx",
+ .val = 'E',
+ },
+ {
+ .name = "no-event-idx",
+ .val = 'e',
+ },
+ {
+ .name = "indirect",
+ .val = 'I',
+ },
+ {
+ .name = "no-indirect",
+ .val = 'i',
+ },
+ {
+ .name = "virtio-1",
+ .val = '1',
+ },
+ {
+ .name = "no-virtio-1",
+ .val = '0',
+ },
+ {
+ .name = "delayed-interrupt",
+ .val = 'D',
+ },
+ {
+ .name = "no-delayed-interrupt",
+ .val = 'd',
+ },
+ {
+ .name = "buf-num",
+ .val = 'n',
+ .has_arg = required_argument,
+ },
+ {
+ .name = "batch",
+ .val = 'b',
+ .has_arg = required_argument,
+ },
+ {
+ }
+};
+
+static void help(int status)
+{
+ fprintf(stderr, "Usage: vhost_net_test [--help]"
+ " [--no-indirect]"
+ " [--no-event-idx]"
+ " [--no-virtio-1]"
+ " [--delayed-interrupt]"
+ " [--buf-num]"
+ "\n");
+
+ exit(status);
+}
+
+int main(int argc, char **argv)
+{
+ unsigned long long features = (1ULL << VIRTIO_RING_F_INDIRECT_DESC) |
+ (1ULL << VIRTIO_RING_F_EVENT_IDX) | (1ULL << VIRTIO_F_VERSION_1);
+ char tun_name[IFNAMSIZ];
+ long nbufs = 0x100000;
+ struct vdev_info dev;
+ bool delayed = false;
+ int o, fd;
+
+ for (;;) {
+ o = getopt_long(argc, argv, optstring, longopts, NULL);
+ switch (o) {
+ case -1:
+ goto done;
+ case '?':
+ help(2);
+ case 'e':
+ features &= ~(1ULL << VIRTIO_RING_F_EVENT_IDX);
+ break;
+ case 'h':
+ help(0);
+ case 'i':
+ features &= ~(1ULL << VIRTIO_RING_F_INDIRECT_DESC);
+ break;
+ case '0':
+ features &= ~(1ULL << VIRTIO_F_VERSION_1);
+ break;
+ case 'D':
+ delayed = true;
+ break;
+ case 'n':
+ nbufs = strtol(optarg, NULL, 10);
+ assert(nbufs > 0);
+ break;
+ default:
+ assert(0);
+ break;
+ }
+ }
+
+done:
+ memset(&dev, 0, sizeof(dev));
+ snprintf(tun_name, IFNAMSIZ, "tun_%d", getpid());
+
+ fd = tun_alloc(&dev, tun_name);
+ assert(fd >= 0);
+
+ vdev_info_init(&dev, features);
+ vq_info_add(&dev, 0, DESC_NUM, fd);
+ vq_info_add(&dev, 1, DESC_NUM, fd);
+ vdev_create_socket(&dev, tun_name);
+
+ run_rx_test(&dev, &dev.vqs[0], delayed, nbufs);
+ run_tx_test(&dev, &dev.vqs[1], delayed, nbufs);
+
+ return 0;
+}
--
2.33.0
^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH net-next v5 5/5] tools: virtio: introduce vhost_net_test
2024-02-05 12:45 ` [PATCH net-next v5 5/5] tools: virtio: introduce vhost_net_test Yunsheng Lin
@ 2024-02-06 3:08 ` Jason Wang
2024-02-06 7:23 ` Yunsheng Lin
0 siblings, 1 reply; 8+ messages in thread
From: Jason Wang @ 2024-02-06 3:08 UTC (permalink / raw)
To: Yunsheng Lin
Cc: davem, kuba, pabeni, netdev, linux-kernel, Michael S. Tsirkin,
Xuan Zhuo, virtualization
On Mon, Feb 5, 2024 at 8:46 PM Yunsheng Lin <linyunsheng@huawei.com> wrote:
>
> introduce vhost_net_test for both vhost_net tx and rx basing
> on virtio_test to test vhost_net changing in the kernel.
>
> Steps for vhost_net tx testing:
> 1. Prepare a out buf.
> 2. Kick the vhost_net to do tx processing.
> 3. Do the receiving in the tun side.
> 4. verify the data received by tun is correct.
>
> Steps for vhost_net rx testing:
> 1. Prepare a in buf.
> 2. Do the sending in the tun side.
> 3. Kick the vhost_net to do rx processing.
> 4. verify the data received by vhost_net is correct.
>
> Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
> ---
> tools/virtio/.gitignore | 1 +
> tools/virtio/Makefile | 8 +-
> tools/virtio/linux/virtio_config.h | 4 +
> tools/virtio/vhost_net_test.c | 536 +++++++++++++++++++++++++++++
> 4 files changed, 546 insertions(+), 3 deletions(-)
> create mode 100644 tools/virtio/vhost_net_test.c
>
> diff --git a/tools/virtio/.gitignore b/tools/virtio/.gitignore
> index 9934d48d9a55..7e47b281c442 100644
> --- a/tools/virtio/.gitignore
> +++ b/tools/virtio/.gitignore
> @@ -1,5 +1,6 @@
> # SPDX-License-Identifier: GPL-2.0-only
> *.d
> virtio_test
> +vhost_net_test
> vringh_test
> virtio-trace/trace-agent
> diff --git a/tools/virtio/Makefile b/tools/virtio/Makefile
> index d128925980e0..e25e99c1c3b7 100644
> --- a/tools/virtio/Makefile
> +++ b/tools/virtio/Makefile
> @@ -1,8 +1,9 @@
> # SPDX-License-Identifier: GPL-2.0
> all: test mod
> -test: virtio_test vringh_test
> +test: virtio_test vringh_test vhost_net_test
> virtio_test: virtio_ring.o virtio_test.o
> vringh_test: vringh_test.o vringh.o virtio_ring.o
> +vhost_net_test: virtio_ring.o vhost_net_test.o
>
> try-run = $(shell set -e; \
> if ($(1)) >/dev/null 2>&1; \
> @@ -49,6 +50,7 @@ oot-clean: OOT_BUILD+=clean
>
> .PHONY: all test mod clean vhost oot oot-clean oot-build
> clean:
> - ${RM} *.o vringh_test virtio_test vhost_test/*.o vhost_test/.*.cmd \
> - vhost_test/Module.symvers vhost_test/modules.order *.d
> + ${RM} *.o vringh_test virtio_test vhost_net_test vhost_test/*.o \
> + vhost_test/.*.cmd vhost_test/Module.symvers \
> + vhost_test/modules.order *.d
> -include *.d
> diff --git a/tools/virtio/linux/virtio_config.h b/tools/virtio/linux/virtio_config.h
> index 2a8a70e2a950..42a564f22f2d 100644
> --- a/tools/virtio/linux/virtio_config.h
> +++ b/tools/virtio/linux/virtio_config.h
> @@ -1,4 +1,6 @@
> /* SPDX-License-Identifier: GPL-2.0 */
> +#ifndef LINUX_VIRTIO_CONFIG_H
> +#define LINUX_VIRTIO_CONFIG_H
> #include <linux/virtio_byteorder.h>
> #include <linux/virtio.h>
> #include <uapi/linux/virtio_config.h>
> @@ -95,3 +97,5 @@ static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val)
> {
> return __cpu_to_virtio64(virtio_is_little_endian(vdev), val);
> }
> +
> +#endif
> diff --git a/tools/virtio/vhost_net_test.c b/tools/virtio/vhost_net_test.c
> new file mode 100644
> index 000000000000..6c41204e6707
> --- /dev/null
> +++ b/tools/virtio/vhost_net_test.c
> @@ -0,0 +1,536 @@
> +// SPDX-License-Identifier: GPL-2.0
> +#define _GNU_SOURCE
> +#include <getopt.h>
> +#include <limits.h>
> +#include <string.h>
> +#include <poll.h>
> +#include <sys/eventfd.h>
> +#include <stdlib.h>
> +#include <assert.h>
> +#include <unistd.h>
> +#include <sys/ioctl.h>
> +#include <sys/stat.h>
> +#include <sys/types.h>
> +#include <fcntl.h>
> +#include <stdbool.h>
> +#include <linux/vhost.h>
> +#include <linux/if.h>
> +#include <linux/if_tun.h>
> +#include <linux/in.h>
> +#include <linux/if_packet.h>
> +#include <linux/virtio_net.h>
> +#include <netinet/ether.h>
> +
> +#define HDR_LEN sizeof(struct virtio_net_hdr_mrg_rxbuf)
> +#define TEST_BUF_LEN 256
> +#define TEST_PTYPE ETH_P_LOOPBACK
> +#define DESC_NUM 256
> +
> +/* Used by implementation of kmalloc() in tools/virtio/linux/kernel.h */
> +void *__kmalloc_fake, *__kfree_ignore_start, *__kfree_ignore_end;
> +
> +struct vq_info {
> + int kick;
> + int call;
> + int idx;
> + long started;
> + long completed;
> + struct pollfd fds;
> + void *ring;
> + /* copy used for control */
> + struct vring vring;
> + struct virtqueue *vq;
> +};
> +
> +struct vdev_info {
> + struct virtio_device vdev;
> + int control;
> + struct vq_info vqs[2];
> + int nvqs;
> + void *buf;
> + size_t buf_size;
> + char *test_buf;
> + char *res_buf;
> + struct vhost_memory *mem;
> + int sock;
> + int ifindex;
> + unsigned char mac[ETHER_ADDR_LEN];
> +};
> +
> +static int tun_alloc(struct vdev_info *dev, char *tun_name)
> +{
> + struct ifreq ifr;
> + int len = HDR_LEN;
> + int fd, e;
> +
> + fd = open("/dev/net/tun", O_RDWR);
> + if (fd < 0) {
> + perror("Cannot open /dev/net/tun");
> + return fd;
> + }
> +
> + memset(&ifr, 0, sizeof(ifr));
> +
> + ifr.ifr_flags = IFF_TAP | IFF_NO_PI | IFF_VNET_HDR;
> + strncpy(ifr.ifr_name, tun_name, IFNAMSIZ);
> +
> + e = ioctl(fd, TUNSETIFF, &ifr);
> + if (e < 0) {
> + perror("ioctl[TUNSETIFF]");
> + close(fd);
> + return e;
> + }
> +
> + e = ioctl(fd, TUNSETVNETHDRSZ, &len);
> + if (e < 0) {
> + perror("ioctl[TUNSETVNETHDRSZ]");
> + close(fd);
> + return e;
> + }
> +
> + e = ioctl(fd, SIOCGIFHWADDR, &ifr);
> + if (e < 0) {
> + perror("ioctl[SIOCGIFHWADDR]");
> + close(fd);
> + return e;
> + }
> +
> + memcpy(dev->mac, &ifr.ifr_hwaddr.sa_data, ETHER_ADDR_LEN);
> + return fd;
> +}
> +
> +static void vdev_create_socket(struct vdev_info *dev, char *tun_name)
> +{
> + struct ifreq ifr;
> +
> + dev->sock = socket(AF_PACKET, SOCK_RAW, htons(TEST_PTYPE));
> + assert(dev->sock != -1);
> +
> + strncpy(ifr.ifr_name, tun_name, IFNAMSIZ);
> + assert(ioctl(dev->sock, SIOCGIFINDEX, &ifr) >= 0);
> +
> + dev->ifindex = ifr.ifr_ifindex;
> +
> + /* Set the flags that bring the device up */
> + assert(ioctl(dev->sock, SIOCGIFFLAGS, &ifr) >= 0);
> + ifr.ifr_flags |= (IFF_UP | IFF_RUNNING);
> + assert(ioctl(dev->sock, SIOCSIFFLAGS, &ifr) >= 0);
> +}
> +
> +static void vdev_send_packet(struct vdev_info *dev)
> +{
> + char *sendbuf = dev->test_buf + HDR_LEN;
> + struct sockaddr_ll saddrll = {0};
> + int sockfd = dev->sock;
> + int ret;
> +
> + saddrll.sll_family = PF_PACKET;
> + saddrll.sll_ifindex = dev->ifindex;
> + saddrll.sll_halen = ETH_ALEN;
> + saddrll.sll_protocol = htons(TEST_PTYPE);
> +
> + ret = sendto(sockfd, sendbuf, TEST_BUF_LEN, 0,
> + (struct sockaddr *)&saddrll,
> + sizeof(struct sockaddr_ll));
> + assert(ret >= 0);
> +}
> +
> +static bool vq_notify(struct virtqueue *vq)
> +{
> + struct vq_info *info = vq->priv;
> + unsigned long long v = 1;
> + int r;
> +
> + r = write(info->kick, &v, sizeof(v));
> + assert(r == sizeof(v));
> +
> + return true;
> +}
> +
> +static void vhost_vq_setup(struct vdev_info *dev, struct vq_info *info)
> +{
> + struct vhost_vring_addr addr = {
> + .index = info->idx,
> + .desc_user_addr = (uint64_t)(unsigned long)info->vring.desc,
> + .avail_user_addr = (uint64_t)(unsigned long)info->vring.avail,
> + .used_user_addr = (uint64_t)(unsigned long)info->vring.used,
> + };
> + struct vhost_vring_state state = { .index = info->idx };
> + struct vhost_vring_file file = { .index = info->idx };
> + int r;
> +
> + state.num = info->vring.num;
> + r = ioctl(dev->control, VHOST_SET_VRING_NUM, &state);
> + assert(r >= 0);
> +
> + state.num = 0;
> + r = ioctl(dev->control, VHOST_SET_VRING_BASE, &state);
> + assert(r >= 0);
> +
> + r = ioctl(dev->control, VHOST_SET_VRING_ADDR, &addr);
> + assert(r >= 0);
> +
> + file.fd = info->kick;
> + r = ioctl(dev->control, VHOST_SET_VRING_KICK, &file);
> + assert(r >= 0);
> +}
> +
> +static void vq_reset(struct vq_info *info, int num, struct virtio_device *vdev)
> +{
> + if (info->vq)
> + vring_del_virtqueue(info->vq);
> +
> + memset(info->ring, 0, vring_size(num, 4096));
> + vring_init(&info->vring, num, info->ring, 4096);
> + info->vq = vring_new_virtqueue(info->idx, num, 4096, vdev, true, false,
> + info->ring, vq_notify, NULL, "test");
> + assert(info->vq);
> + info->vq->priv = info;
> +}
> +
> +static void vq_info_add(struct vdev_info *dev, int idx, int num, int fd)
> +{
> + struct vhost_vring_file backend = { .index = idx, .fd = fd };
> + struct vq_info *info = &dev->vqs[idx];
> + int r;
> +
> + info->idx = idx;
> + info->kick = eventfd(0, EFD_NONBLOCK);
> + r = posix_memalign(&info->ring, 4096, vring_size(num, 4096));
> + assert(r >= 0);
> + vq_reset(info, num, &dev->vdev);
> + vhost_vq_setup(dev, info);
> +
> + r = ioctl(dev->control, VHOST_NET_SET_BACKEND, &backend);
> + assert(!r);
> +}
> +
> +static void vdev_info_init(struct vdev_info *dev, unsigned long long features)
> +{
> + struct ether_header *eh;
> + int i, r;
> +
> + dev->vdev.features = features;
> + INIT_LIST_HEAD(&dev->vdev.vqs);
> + spin_lock_init(&dev->vdev.vqs_list_lock);
> +
> + dev->buf_size = (HDR_LEN + TEST_BUF_LEN) * 2;
> + dev->buf = malloc(dev->buf_size);
> + assert(dev->buf);
> + dev->test_buf = dev->buf;
> + dev->res_buf = dev->test_buf + HDR_LEN + TEST_BUF_LEN;
> +
> + memset(dev->test_buf, 0, HDR_LEN + TEST_BUF_LEN);
> + eh = (struct ether_header *)(dev->test_buf + HDR_LEN);
> + eh->ether_type = htons(TEST_PTYPE);
> + memcpy(eh->ether_dhost, dev->mac, ETHER_ADDR_LEN);
> + memcpy(eh->ether_shost, dev->mac, ETHER_ADDR_LEN);
> +
> + for (i = sizeof(*eh); i < TEST_BUF_LEN; i++)
> + dev->test_buf[i + HDR_LEN] = (char)i;
> +
> + dev->control = open("/dev/vhost-net", O_RDWR);
> + assert(dev->control >= 0);
> +
> + r = ioctl(dev->control, VHOST_SET_OWNER, NULL);
> + assert(r >= 0);
> +
> + dev->mem = malloc(offsetof(struct vhost_memory, regions) +
> + sizeof(dev->mem->regions[0]));
> + assert(dev->mem);
> + memset(dev->mem, 0, offsetof(struct vhost_memory, regions) +
> + sizeof(dev->mem->regions[0]));
> + dev->mem->nregions = 1;
> + dev->mem->regions[0].guest_phys_addr = (long)dev->buf;
> + dev->mem->regions[0].userspace_addr = (long)dev->buf;
> + dev->mem->regions[0].memory_size = dev->buf_size;
> +
> + r = ioctl(dev->control, VHOST_SET_MEM_TABLE, dev->mem);
> + assert(r >= 0);
> +
> + r = ioctl(dev->control, VHOST_SET_FEATURES, &features);
> + assert(r >= 0);
> +
> + dev->nvqs = 2;
> +}
> +
> +static void wait_for_interrupt(struct vq_info *vq)
> +{
> + unsigned long long val;
> +
> + poll(&vq->fds, 1, -1);
It's not good to wait indefinitely.
> +
> + if (vq->fds.revents & POLLIN)
> + read(vq->fds.fd, &val, sizeof(val));
> +}
> +
> +static void verify_res_buf(char *res_buf)
> +{
> + int i;
> +
> + for (i = ETHER_HDR_LEN; i < TEST_BUF_LEN; i++)
> + assert(res_buf[i] == (char)i);
> +}
> +
> +static void run_tx_test(struct vdev_info *dev, struct vq_info *vq,
> + bool delayed, int bufs)
> +{
> + long long spurious = 0;
> + struct scatterlist sl;
> + unsigned int len;
> + int r;
> +
> + for (;;) {
> + long started_before = vq->started;
> + long completed_before = vq->completed;
> +
> + virtqueue_disable_cb(vq->vq);
> + do {
> + while (vq->started < bufs &&
> + (vq->started - vq->completed) < 1) {
> + sg_init_one(&sl, dev->test_buf, HDR_LEN + TEST_BUF_LEN);
> + r = virtqueue_add_outbuf(vq->vq, &sl, 1,
> + dev->test_buf + vq->started,
> + GFP_ATOMIC);
> + if (unlikely(r != 0))
> + break;
> +
> + ++vq->started;
If we never decrease started/completed shouldn't we use unsigned here?
(as well as completed)
Otherwise we may get unexpected results for vq->started as well as
vq->completed.
> +
> + if (unlikely(!virtqueue_kick(vq->vq))) {
> + r = -1;
> + break;
> + }
> + }
> +
> + if (vq->started >= bufs)
> + r = -1;
Which condition do we reach here?
> +
> + /* Flush out completed bufs if any */
> + while (virtqueue_get_buf(vq->vq, &len)) {
> + int n;
> +
> + n = recvfrom(dev->sock, dev->res_buf, TEST_BUF_LEN, 0, NULL, NULL);
> + assert(n == TEST_BUF_LEN);
> + verify_res_buf(dev->res_buf);
> +
> + ++vq->completed;
> + r = 0;
> + }
> + } while (r == 0);
> +
> + if (vq->completed == completed_before && vq->started == started_before)
> + ++spurious;
> +
> + assert(vq->completed <= bufs);
> + assert(vq->started <= bufs);
> + if (vq->completed == bufs)
> + break;
> +
> + if (delayed) {
> + if (virtqueue_enable_cb_delayed(vq->vq))
> + wait_for_interrupt(vq);
> + } else {
> + if (virtqueue_enable_cb(vq->vq))
> + wait_for_interrupt(vq);
> + }
This could be simplified with
if (delayed)
else
wait_for_interrupt(vq)
> + }
> + printf("TX spurious wakeups: 0x%llx started=0x%lx completed=0x%lx\n",
> + spurious, vq->started, vq->completed);
> +}
> +
> +static void run_rx_test(struct vdev_info *dev, struct vq_info *vq,
> + bool delayed, int bufs)
> +{
> + long long spurious = 0;
> + struct scatterlist sl;
> + unsigned int len;
> + int r;
> +
> + for (;;) {
> + long started_before = vq->started;
> + long completed_before = vq->completed;
> +
> + do {
> + while (vq->started < bufs &&
> + (vq->started - vq->completed) < 1) {
> + sg_init_one(&sl, dev->res_buf, HDR_LEN + TEST_BUF_LEN);
> +
> + r = virtqueue_add_inbuf(vq->vq, &sl, 1,
> + dev->res_buf + vq->started,
> + GFP_ATOMIC);
> + if (unlikely(r != 0))
> + break;
> +
> + ++vq->started;
> +
> + vdev_send_packet(dev);
> +
> + if (unlikely(!virtqueue_kick(vq->vq))) {
> + r = -1;
> + break;
> + }
> + }
> +
> + if (vq->started >= bufs)
> + r = -1;
> +
> + /* Flush out completed bufs if any */
> + while (virtqueue_get_buf(vq->vq, &len)) {
> + struct ether_header *eh;
> +
> + eh = (struct ether_header *)(dev->res_buf + HDR_LEN);
> +
> + /* tun netdev is up and running, ignore the
> + * non-TEST_PTYPE packet.
> + */
> + if (eh->ether_type != htons(TEST_PTYPE)) {
> + ++vq->completed;
> + r = 0;
> + continue;
> + }
> +
> + assert(len == TEST_BUF_LEN + HDR_LEN);
> + verify_res_buf(dev->res_buf + HDR_LEN);
Let's simply the logic here:
if (ether_type == htons()) {
assert()
verify_res_buf()
}
r = 0;
++vq->completed;
Others look good.
Thanks
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH net-next v5 5/5] tools: virtio: introduce vhost_net_test
2024-02-06 3:08 ` Jason Wang
@ 2024-02-06 7:23 ` Yunsheng Lin
0 siblings, 0 replies; 8+ messages in thread
From: Yunsheng Lin @ 2024-02-06 7:23 UTC (permalink / raw)
To: Jason Wang
Cc: davem, kuba, pabeni, netdev, linux-kernel, Michael S. Tsirkin,
Xuan Zhuo, virtualization
On 2024/2/6 11:08, Jason Wang wrote:
...
>> +
>> +static void wait_for_interrupt(struct vq_info *vq)
>> +{
>> + unsigned long long val;
>> +
>> + poll(&vq->fds, 1, -1);
>
> It's not good to wait indefinitely.
How about a timeout value of 100ms as below?
poll(&vq->fds, 1, 100);
>
>> +
>> + if (vq->fds.revents & POLLIN)
>> + read(vq->fds.fd, &val, sizeof(val));
>> +}
>> +
>> +static void verify_res_buf(char *res_buf)
>> +{
>> + int i;
>> +
>> + for (i = ETHER_HDR_LEN; i < TEST_BUF_LEN; i++)
>> + assert(res_buf[i] == (char)i);
>> +}
>> +
>> +static void run_tx_test(struct vdev_info *dev, struct vq_info *vq,
>> + bool delayed, int bufs)
>> +{
>> + long long spurious = 0;
>> + struct scatterlist sl;
>> + unsigned int len;
>> + int r;
>> +
>> + for (;;) {
>> + long started_before = vq->started;
>> + long completed_before = vq->completed;
>> +
>> + virtqueue_disable_cb(vq->vq);
>> + do {
>> + while (vq->started < bufs &&
>> + (vq->started - vq->completed) < 1) {
>> + sg_init_one(&sl, dev->test_buf, HDR_LEN + TEST_BUF_LEN);
>> + r = virtqueue_add_outbuf(vq->vq, &sl, 1,
>> + dev->test_buf + vq->started,
>> + GFP_ATOMIC);
>> + if (unlikely(r != 0))
>> + break;
>> +
>> + ++vq->started;
>
> If we never decrease started/completed shouldn't we use unsigned here?
> (as well as completed)
>
> Otherwise we may get unexpected results for vq->started as well as
> vq->completed.
We have "vq->started < bufs" checking before the increasing as above,
and there is 'assert(nbufs > 0)' when getting optarg in main(), which
means we never allow started/completed to be greater than nbufs as
my understanding.
>
>> +
>> + if (unlikely(!virtqueue_kick(vq->vq))) {
>> + r = -1;
>> + break;
>> + }
>> + }
>> +
>> + if (vq->started >= bufs)
>> + r = -1;
>
> Which condition do we reach here?
It is also a copy & paste of virtio_test.c
It means we have finished adding the outbuf in virtqueue, and set 'r'
to be '-1' so that we can break the inner while loop if there is no
result for virtqueue_get_buf() as my understanding.
>
>> +
>> + /* Flush out completed bufs if any */
>> + while (virtqueue_get_buf(vq->vq, &len)) {
>> + int n;
>> +
>> + n = recvfrom(dev->sock, dev->res_buf, TEST_BUF_LEN, 0, NULL, NULL);
>> + assert(n == TEST_BUF_LEN);
>> + verify_res_buf(dev->res_buf);
>> +
>> + ++vq->completed;
>> + r = 0;
>> + }
>> + } while (r == 0);
>> +
>> + if (vq->completed == completed_before && vq->started == started_before)
>> + ++spurious;
>> +
>> + assert(vq->completed <= bufs);
>> + assert(vq->started <= bufs);
>> + if (vq->completed == bufs)
>> + break;
>> +
>> + if (delayed) {
>> + if (virtqueue_enable_cb_delayed(vq->vq))
>> + wait_for_interrupt(vq);
>> + } else {
>> + if (virtqueue_enable_cb(vq->vq))
>> + wait_for_interrupt(vq);
>> + }
>
> This could be simplified with
>
> if (delayed)
> else
>
> wait_for_interrupt(vq)
I am not sure if I understand the above comment.
The wait_for_interrupt() is only called conditionally depending on the
returning of virtqueue_enable_cb_delayed() and virtqueue_enable_cb().
>
>> + }
>> + printf("TX spurious wakeups: 0x%llx started=0x%lx completed=0x%lx\n",
>> + spurious, vq->started, vq->completed);
>> +}
>> +
...
>> +
>> + /* Flush out completed bufs if any */
>> + while (virtqueue_get_buf(vq->vq, &len)) {
>> + struct ether_header *eh;
>> +
>> + eh = (struct ether_header *)(dev->res_buf + HDR_LEN);
>> +
>> + /* tun netdev is up and running, ignore the
>> + * non-TEST_PTYPE packet.
>> + */
>> + if (eh->ether_type != htons(TEST_PTYPE)) {
>> + ++vq->completed;
>> + r = 0;
>> + continue;
>> + }
>> +
>> + assert(len == TEST_BUF_LEN + HDR_LEN);
>> + verify_res_buf(dev->res_buf + HDR_LEN);
>
> Let's simply the logic here:
>
> if (ether_type == htons()) {
> assert()
> verify_res_buf()
> }
>
> r = 0;
> ++vq->completed;
Sure.
>
> Others look good.
Thanks for the reviewing.
>
> Thanks
>
> .
>
^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2024-02-06 7:24 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2024-02-05 12:45 [PATCH net-next v5 0/5] remove page frag implementation in vhost_net Yunsheng Lin
2024-02-05 12:45 ` [PATCH net-next v5 1/5] mm/page_alloc: modify page_frag_alloc_align() to accept align as an argument Yunsheng Lin
2024-02-05 12:45 ` [PATCH net-next v5 2/5] page_frag: unify gfp bits for order 3 page allocation Yunsheng Lin
2024-02-05 12:45 ` [PATCH net-next v5 3/5] net: introduce page_frag_cache_drain() Yunsheng Lin
2024-02-05 12:45 ` [PATCH net-next v5 4/5] vhost/net: remove vhost_net_page_frag_refill() Yunsheng Lin
2024-02-05 12:45 ` [PATCH net-next v5 5/5] tools: virtio: introduce vhost_net_test Yunsheng Lin
2024-02-06 3:08 ` Jason Wang
2024-02-06 7:23 ` Yunsheng Lin
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