| Message ID | 508fef55188d4e1160747ead64c6dcda36735880.1606555939.git.xuanzhuo@linux.alibaba.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 3413f04141aa440c71da187755e8e22f5093ce83 |
| Delegated to: | BPF |
| Headers | show |
| Series | xsk: fix for xsk_poll writeable | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | success | Link |
| netdev/fixes_present | fail | Series targets non-next tree, but doesn't contain any Fixes tags |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Clearly marked for bpf |
| netdev/subject_prefix | success | Link |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | success | Errors and warnings before: 1 this patch: 1 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 52 lines checked |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 1 this patch: 1 |
| netdev/header_inline | success | Link |
| netdev/stable | success | Stable not CCed |
On Tue, Dec 1, 2020 at 2:59 PM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote: > > Modify the tx writeable condition from the queue is not full to the > number of present tx queues is less than the half of the total number > of queues. Because the tx queue not full is a very short time, this will > cause a large number of EPOLLOUT events, and cause a large number of > process wake up. And the Fixes label here should be: Fixes: 35fcde7f8deb ("xsk: support for Tx") > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > Acked-by: Magnus Karlsson <magnus.karlsson@intel.com> > --- > net/xdp/xsk.c | 16 +++++++++++++--- > net/xdp/xsk_queue.h | 6 ++++++ > 2 files changed, 19 insertions(+), 3 deletions(-) > > diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c > index 9bbfd8a..6250447 100644 > --- a/net/xdp/xsk.c > +++ b/net/xdp/xsk.c > @@ -211,6 +211,14 @@ static int __xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp, u32 len, > return 0; > } > > +static bool xsk_tx_writeable(struct xdp_sock *xs) > +{ > + if (xskq_cons_present_entries(xs->tx) > xs->tx->nentries / 2) > + return false; > + > + return true; > +} > + > static bool xsk_is_bound(struct xdp_sock *xs) > { > if (READ_ONCE(xs->state) == XSK_BOUND) { > @@ -296,7 +304,8 @@ void xsk_tx_release(struct xsk_buff_pool *pool) > rcu_read_lock(); > list_for_each_entry_rcu(xs, &pool->xsk_tx_list, tx_list) { > __xskq_cons_release(xs->tx); > - xs->sk.sk_write_space(&xs->sk); > + if (xsk_tx_writeable(xs)) > + xs->sk.sk_write_space(&xs->sk); > } > rcu_read_unlock(); > } > @@ -436,7 +445,8 @@ static int xsk_generic_xmit(struct sock *sk) > > out: > if (sent_frame) > - sk->sk_write_space(sk); > + if (xsk_tx_writeable(xs)) > + sk->sk_write_space(sk); > > mutex_unlock(&xs->mutex); > return err; > @@ -493,7 +503,7 @@ static __poll_t xsk_poll(struct file *file, struct socket *sock, > > if (xs->rx && !xskq_prod_is_empty(xs->rx)) > mask |= EPOLLIN | EPOLLRDNORM; > - if (xs->tx && !xskq_cons_is_full(xs->tx)) > + if (xs->tx && xsk_tx_writeable(xs)) > mask |= EPOLLOUT | EPOLLWRNORM; > > return mask; > diff --git a/net/xdp/xsk_queue.h b/net/xdp/xsk_queue.h > index cdb9cf3..9e71b9f 100644 > --- a/net/xdp/xsk_queue.h > +++ b/net/xdp/xsk_queue.h > @@ -264,6 +264,12 @@ static inline bool xskq_cons_is_full(struct xsk_queue *q) > q->nentries; > } > > +static inline u32 xskq_cons_present_entries(struct xsk_queue *q) > +{ > + /* No barriers needed since data is not accessed */ > + return READ_ONCE(q->ring->producer) - READ_ONCE(q->ring->consumer); > +} > + > /* Functions for producers */ > > static inline bool xskq_prod_is_full(struct xsk_queue *q) > -- > 1.8.3.1 >
diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c index 9bbfd8a..6250447 100644 --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -211,6 +211,14 @@ static int __xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp, u32 len, return 0; } +static bool xsk_tx_writeable(struct xdp_sock *xs) +{ + if (xskq_cons_present_entries(xs->tx) > xs->tx->nentries / 2) + return false; + + return true; +} + static bool xsk_is_bound(struct xdp_sock *xs) { if (READ_ONCE(xs->state) == XSK_BOUND) { @@ -296,7 +304,8 @@ void xsk_tx_release(struct xsk_buff_pool *pool) rcu_read_lock(); list_for_each_entry_rcu(xs, &pool->xsk_tx_list, tx_list) { __xskq_cons_release(xs->tx); - xs->sk.sk_write_space(&xs->sk); + if (xsk_tx_writeable(xs)) + xs->sk.sk_write_space(&xs->sk); } rcu_read_unlock(); } @@ -436,7 +445,8 @@ static int xsk_generic_xmit(struct sock *sk) out: if (sent_frame) - sk->sk_write_space(sk); + if (xsk_tx_writeable(xs)) + sk->sk_write_space(sk); mutex_unlock(&xs->mutex); return err; @@ -493,7 +503,7 @@ static __poll_t xsk_poll(struct file *file, struct socket *sock, if (xs->rx && !xskq_prod_is_empty(xs->rx)) mask |= EPOLLIN | EPOLLRDNORM; - if (xs->tx && !xskq_cons_is_full(xs->tx)) + if (xs->tx && xsk_tx_writeable(xs)) mask |= EPOLLOUT | EPOLLWRNORM; return mask; diff --git a/net/xdp/xsk_queue.h b/net/xdp/xsk_queue.h index cdb9cf3..9e71b9f 100644 --- a/net/xdp/xsk_queue.h +++ b/net/xdp/xsk_queue.h @@ -264,6 +264,12 @@ static inline bool xskq_cons_is_full(struct xsk_queue *q) q->nentries; } +static inline u32 xskq_cons_present_entries(struct xsk_queue *q) +{ + /* No barriers needed since data is not accessed */ + return READ_ONCE(q->ring->producer) - READ_ONCE(q->ring->consumer); +} + /* Functions for producers */ static inline bool xskq_prod_is_full(struct xsk_queue *q)