diff options
| author | Björn Töpel <bjorn.topel@intel.com> | 2020-11-30 19:51:59 +0100 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2020-12-01 00:09:25 +0100 |
| commit | e392081837283fbe5df1837fd85012ae5bfae098 (patch) | |
| tree | f0c1d7ea91db4dfc7f03b59818246ac15d9ca2a7 /net/xdp/xsk.c | |
| parent | 45a86681844e375bef6f6add272ccc309bb6a08d (diff) | |
xsk: Check need wakeup flag in sendmsg()
Add a check for need wake up in sendmsg(), so that if a user calls
sendmsg() when no wakeup is needed, do not trigger a wakeup.
To simplify the need wakeup check in the syscall, unconditionally
enable the need wakeup flag for Tx. This has a side-effect for poll();
If poll() is called for a socket without enabled need wakeup, a Tx
wakeup is unconditionally performed.
The wakeup matrix for AF_XDP now looks like:
need wakeup | poll() | sendmsg() | recvmsg()
------------+--------------+-------------+------------
disabled | wake Tx | wake Tx | nop
enabled | check flag; | check flag; | check flag;
| wake Tx/Rx | wake Tx | wake Rx
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20201130185205.196029-5-bjorn.topel@gmail.com
Diffstat (limited to 'net/xdp/xsk.c')
| -rw-r--r-- | net/xdp/xsk.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c index 1d1e0cd51a95..c72b4dba2878 100644 --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -522,13 +522,17 @@ static int xsk_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len) bool need_wait = !(m->msg_flags & MSG_DONTWAIT); struct sock *sk = sock->sk; struct xdp_sock *xs = xdp_sk(sk); + struct xsk_buff_pool *pool; if (unlikely(!xsk_is_bound(xs))) return -ENXIO; if (unlikely(need_wait)) return -EOPNOTSUPP; - return __xsk_sendmsg(sk); + pool = xs->pool; + if (pool->cached_need_wakeup & XDP_WAKEUP_TX) + return __xsk_sendmsg(sk); + return 0; } static int xsk_recvmsg(struct socket *sock, struct msghdr *m, size_t len, int flags) |