Den ons 19 dec. 2018 kl 01:55 skrev William Tu <u9012...@gmail.com>:
>
> Currently the xsk_umem_consume_tx expects only the physical NICs so
> the api returns a dma address. This patch introduce the new function
> to return the virtual address, when XSK is used by a virtual device.
>
> Signed-off-by: William Tu <u9012...@gmail.com>
> ---
> include/net/xdp_sock.h | 7 +++++++
> net/xdp/xdp_umem.c | 1 +
> net/xdp/xsk.c | 21 +++++++++++++++++++--
> 3 files changed, 27 insertions(+), 2 deletions(-)
>
> diff --git a/include/net/xdp_sock.h b/include/net/xdp_sock.h
> index 13acb9803a6d..7fefe74f7fb5 100644
> --- a/include/net/xdp_sock.h
> +++ b/include/net/xdp_sock.h
> @@ -81,6 +81,7 @@ u64 *xsk_umem_peek_addr(struct xdp_umem *umem, u64 *addr);
> void xsk_umem_discard_addr(struct xdp_umem *umem);
> void xsk_umem_complete_tx(struct xdp_umem *umem, u32 nb_entries);
> bool xsk_umem_consume_tx(struct xdp_umem *umem, dma_addr_t *dma, u32 *len);
> +bool xsk_umem_consume_tx_virtual(struct xdp_umem *umem, void **addr, u32
> *len);
> void xsk_umem_consume_tx_done(struct xdp_umem *umem);
> struct xdp_umem_fq_reuse *xsk_reuseq_prepare(u32 nentries);
> struct xdp_umem_fq_reuse *xsk_reuseq_swap(struct xdp_umem *umem,
> @@ -165,6 +166,12 @@ static inline bool xsk_umem_consume_tx(struct xdp_umem
> *umem, dma_addr_t *dma,
> return false;
> }
>
> +static inline bool xsk_umem_consume_tx_virtual(struct xdp_umem *umem,
> + void **vaddr, u32 *len)
> +{
> + return false;
> +}
> +
> static inline void xsk_umem_consume_tx_done(struct xdp_umem *umem)
> {
> }
> diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c
> index a264cf2accd0..424ae2538f9f 100644
> --- a/net/xdp/xdp_umem.c
> +++ b/net/xdp/xdp_umem.c
> @@ -60,6 +60,7 @@ struct xdp_umem *xdp_get_umem_from_qid(struct net_device
> *dev,
>
> return NULL;
> }
> +EXPORT_SYMBOL(xdp_get_umem_from_qid);
>
> static void xdp_clear_umem_at_qid(struct net_device *dev, u16 queue_id)
> {
> diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c
> index 07156f43d295..a6ca0c0f0330 100644
> --- a/net/xdp/xsk.c
> +++ b/net/xdp/xsk.c
> @@ -170,7 +170,8 @@ void xsk_umem_consume_tx_done(struct xdp_umem *umem)
> }
> EXPORT_SYMBOL(xsk_umem_consume_tx_done);
>
> -bool xsk_umem_consume_tx(struct xdp_umem *umem, dma_addr_t *dma, u32 *len)
> +static bool __xsk_umem_consume_tx(struct xdp_umem *umem, dma_addr_t *dma,
> + void **vaddr, u32 *len)
> {
> struct xdp_desc desc;
> struct xdp_sock *xs;
> @@ -183,7 +184,12 @@ bool xsk_umem_consume_tx(struct xdp_umem *umem,
> dma_addr_t *dma, u32 *len)
> if (xskq_produce_addr_lazy(umem->cq, desc.addr))
> goto out;
>
> - *dma = xdp_umem_get_dma(umem, desc.addr);
> + if (dma)
> + *dma = xdp_umem_get_dma(umem, desc.addr);
> +
> + if (vaddr)
> + *vaddr = xdp_umem_get_data(umem, desc.addr);
> +
This function is in the fast-path, so I'm reluctant to introduce the
branching above. What do think about something like this instead?
diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c
index 80ca48cefc42..458f0977b437 100644
--- a/net/xdp/xsk.c
+++ b/net/xdp/xsk.c
@@ -170,22 +170,19 @@ void xsk_umem_consume_tx_done(struct xdp_umem *umem)
}
EXPORT_SYMBOL(xsk_umem_consume_tx_done);
-bool xsk_umem_consume_tx(struct xdp_umem *umem, dma_addr_t *dma, u32 *len)
+static __always_inline bool __xsk_umem_consume_tx(struct xdp_umem *umem,
+ struct xdp_desc *desc)
{
- struct xdp_desc desc;
struct xdp_sock *xs;
rcu_read_lock();
list_for_each_entry_rcu(xs, &umem->xsk_list, list) {
- if (!xskq_peek_desc(xs->tx, &desc))
+ if (!xskq_peek_desc(xs->tx, desc))
continue;
- if (xskq_produce_addr_lazy(umem->cq, desc.addr))
+ if (xskq_produce_addr_lazy(umem->cq, desc->addr))
goto out;
- *dma = xdp_umem_get_dma(umem, desc.addr);
- *len = desc.len;
-
xskq_discard_desc(xs->tx);
rcu_read_unlock();
return true;
@@ -195,8 +192,35 @@ bool xsk_umem_consume_tx(struct xdp_umem *umem,
dma_addr_t *dma, u32 *len)
rcu_read_unlock();
return false;
}
+
+bool xsk_umem_consume_tx(struct xdp_umem *umem, dma_addr_t *dma, u32 *len)
+{
+ struct xdp_desc desc;
+
+ if (!__xsk_umem_consume_tx(umem, &desc))
+ return false;
+
+ *dma = xdp_umem_get_dma(umem, desc.addr);
+ *len = desc.len;
+
+ return true;
+}
EXPORT_SYMBOL(xsk_umem_consume_tx);
+bool xsk_umem_consume_tx_virtual(struct xdp_umem *umem, void **vaddr, u32 *len)
+{
+ struct xdp_desc desc;
+
+ if (!__xsk_umem_consume_tx(umem, &desc))
+ return false;
+
+ *vaddr = xdp_umem_get_data(umem, desc.addr);
+ *len = desc.len;
+
+ return true;
+}
+EXPORT_SYMBOL(xsk_umem_consume_tx_virtual);
+
static int xsk_zc_xmit(struct sock *sk)
{
struct xdp_sock *xs = xdp_sk(sk);
Björn
> *len = desc.len;
>
> xskq_discard_desc(xs->tx);
> @@ -195,8 +201,19 @@ bool xsk_umem_consume_tx(struct xdp_umem *umem,
> dma_addr_t *dma, u32 *len)
> rcu_read_unlock();
> return false;
> }
> +
> +bool xsk_umem_consume_tx(struct xdp_umem *umem, dma_addr_t *dma, u32 *len)
> +{
> + return __xsk_umem_consume_tx(umem, dma, NULL, len);
> +}
> EXPORT_SYMBOL(xsk_umem_consume_tx);
>
> +bool xsk_umem_consume_tx_virtual(struct xdp_umem *umem, void **addr, u32
> *len)
> +{
> + return __xsk_umem_consume_tx(umem, NULL, addr, len);
> +}
> +EXPORT_SYMBOL(xsk_umem_consume_tx_virtual);
> +
> static int xsk_zc_xmit(struct sock *sk)
> {
> struct xdp_sock *xs = xdp_sk(sk);
> --
> 2.7.4
>
