linux-stable/include/net/busy_poll.h
Daniel Borkmann ba0581749f net, xdp, xsk: fix __sk_mark_napi_id_once napi_id error
Stephen reported the following build error for !CONFIG_NET_RX_BUSY_POLL
built kernels:

  In file included from fs/select.c:32:
  include/net/busy_poll.h: In function 'sk_mark_napi_id_once':
  include/net/busy_poll.h:150:36: error: 'const struct sk_buff' has no member named 'napi_id'
    150 |  __sk_mark_napi_id_once_xdp(sk, skb->napi_id);
        |                                    ^~

Fix it by wrapping a CONFIG_NET_RX_BUSY_POLL around the helpers.

Fixes: b02e5a0ebb ("xsk: Propagate napi_id to XDP socket Rx path")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Björn Töpel <bjorn.topel@intel.com>
Link: https://lore.kernel.org/linux-next/20201201190746.7d3357fb@canb.auug.org.au
2020-12-01 15:51:19 +01:00

163 lines
3.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* net busy poll support
* Copyright(c) 2013 Intel Corporation.
*
* Author: Eliezer Tamir
*
* Contact Information:
* e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
*/
#ifndef _LINUX_NET_BUSY_POLL_H
#define _LINUX_NET_BUSY_POLL_H
#include <linux/netdevice.h>
#include <linux/sched/clock.h>
#include <linux/sched/signal.h>
#include <net/ip.h>
/* 0 - Reserved to indicate value not set
* 1..NR_CPUS - Reserved for sender_cpu
* NR_CPUS+1..~0 - Region available for NAPI IDs
*/
#define MIN_NAPI_ID ((unsigned int)(NR_CPUS + 1))
#define BUSY_POLL_BUDGET 8
#ifdef CONFIG_NET_RX_BUSY_POLL
struct napi_struct;
extern unsigned int sysctl_net_busy_read __read_mostly;
extern unsigned int sysctl_net_busy_poll __read_mostly;
static inline bool net_busy_loop_on(void)
{
return sysctl_net_busy_poll;
}
static inline bool sk_can_busy_loop(const struct sock *sk)
{
return sk->sk_ll_usec && !signal_pending(current);
}
bool sk_busy_loop_end(void *p, unsigned long start_time);
void napi_busy_loop(unsigned int napi_id,
bool (*loop_end)(void *, unsigned long),
void *loop_end_arg, bool prefer_busy_poll, u16 budget);
#else /* CONFIG_NET_RX_BUSY_POLL */
static inline unsigned long net_busy_loop_on(void)
{
return 0;
}
static inline bool sk_can_busy_loop(struct sock *sk)
{
return false;
}
#endif /* CONFIG_NET_RX_BUSY_POLL */
static inline unsigned long busy_loop_current_time(void)
{
#ifdef CONFIG_NET_RX_BUSY_POLL
return (unsigned long)(local_clock() >> 10);
#else
return 0;
#endif
}
/* in poll/select we use the global sysctl_net_ll_poll value */
static inline bool busy_loop_timeout(unsigned long start_time)
{
#ifdef CONFIG_NET_RX_BUSY_POLL
unsigned long bp_usec = READ_ONCE(sysctl_net_busy_poll);
if (bp_usec) {
unsigned long end_time = start_time + bp_usec;
unsigned long now = busy_loop_current_time();
return time_after(now, end_time);
}
#endif
return true;
}
static inline bool sk_busy_loop_timeout(struct sock *sk,
unsigned long start_time)
{
#ifdef CONFIG_NET_RX_BUSY_POLL
unsigned long bp_usec = READ_ONCE(sk->sk_ll_usec);
if (bp_usec) {
unsigned long end_time = start_time + bp_usec;
unsigned long now = busy_loop_current_time();
return time_after(now, end_time);
}
#endif
return true;
}
static inline void sk_busy_loop(struct sock *sk, int nonblock)
{
#ifdef CONFIG_NET_RX_BUSY_POLL
unsigned int napi_id = READ_ONCE(sk->sk_napi_id);
if (napi_id >= MIN_NAPI_ID)
napi_busy_loop(napi_id, nonblock ? NULL : sk_busy_loop_end, sk,
READ_ONCE(sk->sk_prefer_busy_poll),
READ_ONCE(sk->sk_busy_poll_budget) ?: BUSY_POLL_BUDGET);
#endif
}
/* used in the NIC receive handler to mark the skb */
static inline void skb_mark_napi_id(struct sk_buff *skb,
struct napi_struct *napi)
{
#ifdef CONFIG_NET_RX_BUSY_POLL
/* If the skb was already marked with a valid NAPI ID, avoid overwriting
* it.
*/
if (skb->napi_id < MIN_NAPI_ID)
skb->napi_id = napi->napi_id;
#endif
}
/* used in the protocol hanlder to propagate the napi_id to the socket */
static inline void sk_mark_napi_id(struct sock *sk, const struct sk_buff *skb)
{
#ifdef CONFIG_NET_RX_BUSY_POLL
WRITE_ONCE(sk->sk_napi_id, skb->napi_id);
#endif
sk_rx_queue_set(sk, skb);
}
static inline void __sk_mark_napi_id_once(struct sock *sk, unsigned int napi_id)
{
#ifdef CONFIG_NET_RX_BUSY_POLL
if (!READ_ONCE(sk->sk_napi_id))
WRITE_ONCE(sk->sk_napi_id, napi_id);
#endif
}
/* variant used for unconnected sockets */
static inline void sk_mark_napi_id_once(struct sock *sk,
const struct sk_buff *skb)
{
#ifdef CONFIG_NET_RX_BUSY_POLL
__sk_mark_napi_id_once(sk, skb->napi_id);
#endif
}
static inline void sk_mark_napi_id_once_xdp(struct sock *sk,
const struct xdp_buff *xdp)
{
#ifdef CONFIG_NET_RX_BUSY_POLL
__sk_mark_napi_id_once(sk, xdp->rxq->napi_id);
#endif
}
#endif /* _LINUX_NET_BUSY_POLL_H */