[PATCH net-next v16 13/13] netdev: add dmabuf introspection

From: Mina Almasry
Date: Tue Jul 09 2024 - 20:22:40 EST


Add dmabuf information to page_pool stats:

$ ./cli.py --spec ../netlink/specs/netdev.yaml --dump page-pool-get
...
{'dmabuf': 10,
'id': 456,
'ifindex': 3,
'inflight': 1023,
'inflight-mem': 4190208},
{'dmabuf': 10,
'id': 455,
'ifindex': 3,
'inflight': 1023,
'inflight-mem': 4190208},
{'dmabuf': 10,
'id': 454,
'ifindex': 3,
'inflight': 1023,
'inflight-mem': 4190208},
{'dmabuf': 10,
'id': 453,
'ifindex': 3,
'inflight': 1023,
'inflight-mem': 4190208},
{'dmabuf': 10,
'id': 452,
'ifindex': 3,
'inflight': 1023,
'inflight-mem': 4190208},
{'dmabuf': 10,
'id': 451,
'ifindex': 3,
'inflight': 1023,
'inflight-mem': 4190208},
{'dmabuf': 10,
'id': 450,
'ifindex': 3,
'inflight': 1023,
'inflight-mem': 4190208},
{'dmabuf': 10,
'id': 449,
'ifindex': 3,
'inflight': 1023,
'inflight-mem': 4190208},

And queue stats:

$ ./cli.py --spec ../netlink/specs/netdev.yaml --dump queue-get
...
{'dmabuf': 10, 'id': 8, 'ifindex': 3, 'type': 'rx'},
{'dmabuf': 10, 'id': 9, 'ifindex': 3, 'type': 'rx'},
{'dmabuf': 10, 'id': 10, 'ifindex': 3, 'type': 'rx'},
{'dmabuf': 10, 'id': 11, 'ifindex': 3, 'type': 'rx'},
{'dmabuf': 10, 'id': 12, 'ifindex': 3, 'type': 'rx'},
{'dmabuf': 10, 'id': 13, 'ifindex': 3, 'type': 'rx'},
{'dmabuf': 10, 'id': 14, 'ifindex': 3, 'type': 'rx'},
{'dmabuf': 10, 'id': 15, 'ifindex': 3, 'type': 'rx'},

Suggested-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Mina Almasry <almasrymina@xxxxxxxxxx>

---
Documentation/netlink/specs/netdev.yaml | 10 ++++++++++
include/uapi/linux/netdev.h | 2 ++
net/core/netdev-genl.c | 10 ++++++++++
net/core/page_pool_user.c | 4 ++++
tools/include/uapi/linux/netdev.h | 2 ++
5 files changed, 28 insertions(+)

diff --git a/Documentation/netlink/specs/netdev.yaml b/Documentation/netlink/specs/netdev.yaml
index 0c747530c275e..08412c279297b 100644
--- a/Documentation/netlink/specs/netdev.yaml
+++ b/Documentation/netlink/specs/netdev.yaml
@@ -167,6 +167,10 @@ attribute-sets:
"re-attached", they are just waiting to disappear.
Attribute is absent if Page Pool has not been detached, and
can still be used to allocate new memory.
+ -
+ name: dmabuf
+ doc: ID of the dmabuf this page-pool is attached to.
+ type: u32
-
name: page-pool-info
subset-of: page-pool
@@ -268,6 +272,10 @@ attribute-sets:
name: napi-id
doc: ID of the NAPI instance which services this queue.
type: u32
+ -
+ name: dmabuf
+ doc: ID of the dmabuf attached to this queue, if any.
+ type: u32

-
name: qstats
@@ -543,6 +551,7 @@ operations:
- inflight
- inflight-mem
- detach-time
+ - dmabuf
dump:
reply: *pp-reply
config-cond: page-pool
@@ -607,6 +616,7 @@ operations:
- type
- napi-id
- ifindex
+ - dmabuf
dump:
request:
attributes:
diff --git a/include/uapi/linux/netdev.h b/include/uapi/linux/netdev.h
index 91bf3ecc5f1d9..7c308f04e7a06 100644
--- a/include/uapi/linux/netdev.h
+++ b/include/uapi/linux/netdev.h
@@ -93,6 +93,7 @@ enum {
NETDEV_A_PAGE_POOL_INFLIGHT,
NETDEV_A_PAGE_POOL_INFLIGHT_MEM,
NETDEV_A_PAGE_POOL_DETACH_TIME,
+ NETDEV_A_PAGE_POOL_DMABUF,

__NETDEV_A_PAGE_POOL_MAX,
NETDEV_A_PAGE_POOL_MAX = (__NETDEV_A_PAGE_POOL_MAX - 1)
@@ -131,6 +132,7 @@ enum {
NETDEV_A_QUEUE_IFINDEX,
NETDEV_A_QUEUE_TYPE,
NETDEV_A_QUEUE_NAPI_ID,
+ NETDEV_A_QUEUE_DMABUF,

__NETDEV_A_QUEUE_MAX,
NETDEV_A_QUEUE_MAX = (__NETDEV_A_QUEUE_MAX - 1)
diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c
index bd54cf50b658a..e944fd56c6b8e 100644
--- a/net/core/netdev-genl.c
+++ b/net/core/netdev-genl.c
@@ -293,6 +293,7 @@ static int
netdev_nl_queue_fill_one(struct sk_buff *rsp, struct net_device *netdev,
u32 q_idx, u32 q_type, const struct genl_info *info)
{
+ struct net_devmem_dmabuf_binding *binding;
struct netdev_rx_queue *rxq;
struct netdev_queue *txq;
void *hdr;
@@ -312,6 +313,15 @@ netdev_nl_queue_fill_one(struct sk_buff *rsp, struct net_device *netdev,
if (rxq->napi && nla_put_u32(rsp, NETDEV_A_QUEUE_NAPI_ID,
rxq->napi->napi_id))
goto nla_put_failure;
+
+ binding = (struct net_devmem_dmabuf_binding *)
+ rxq->mp_params.mp_priv;
+ if (binding) {
+ if (nla_put_u32(rsp, NETDEV_A_QUEUE_DMABUF,
+ binding->id))
+ goto nla_put_failure;
+ }
+
break;
case NETDEV_QUEUE_TYPE_TX:
txq = netdev_get_tx_queue(netdev, q_idx);
diff --git a/net/core/page_pool_user.c b/net/core/page_pool_user.c
index 3a3277ba167b1..ca13363aea343 100644
--- a/net/core/page_pool_user.c
+++ b/net/core/page_pool_user.c
@@ -212,6 +212,7 @@ static int
page_pool_nl_fill(struct sk_buff *rsp, const struct page_pool *pool,
const struct genl_info *info)
{
+ struct net_devmem_dmabuf_binding *binding = pool->mp_priv;
size_t inflight, refsz;
void *hdr;

@@ -241,6 +242,9 @@ page_pool_nl_fill(struct sk_buff *rsp, const struct page_pool *pool,
pool->user.detach_time))
goto err_cancel;

+ if (binding && nla_put_u32(rsp, NETDEV_A_PAGE_POOL_DMABUF, binding->id))
+ goto err_cancel;
+
genlmsg_end(rsp, hdr);

return 0;
diff --git a/tools/include/uapi/linux/netdev.h b/tools/include/uapi/linux/netdev.h
index 91bf3ecc5f1d9..7c308f04e7a06 100644
--- a/tools/include/uapi/linux/netdev.h
+++ b/tools/include/uapi/linux/netdev.h
@@ -93,6 +93,7 @@ enum {
NETDEV_A_PAGE_POOL_INFLIGHT,
NETDEV_A_PAGE_POOL_INFLIGHT_MEM,
NETDEV_A_PAGE_POOL_DETACH_TIME,
+ NETDEV_A_PAGE_POOL_DMABUF,

__NETDEV_A_PAGE_POOL_MAX,
NETDEV_A_PAGE_POOL_MAX = (__NETDEV_A_PAGE_POOL_MAX - 1)
@@ -131,6 +132,7 @@ enum {
NETDEV_A_QUEUE_IFINDEX,
NETDEV_A_QUEUE_TYPE,
NETDEV_A_QUEUE_NAPI_ID,
+ NETDEV_A_QUEUE_DMABUF,

__NETDEV_A_QUEUE_MAX,
NETDEV_A_QUEUE_MAX = (__NETDEV_A_QUEUE_MAX - 1)
--
2.45.2.803.g4e1b14247a-goog