On Wed, 2017-05-24 at 15:35 +0800, gfree.w...@vip.163.com wrote:
> From: Gao Feng <gfree.w...@vip.163.com>
>
> There are two spots which invoke the sock_rps_record_flow_hash, one is
> sock_rps_record_flow which has already checked rfs_needed. But the other
> is tun_flow_update which doesn't check if the rfs is enabled.
>
> Now rename the original function sock_rps_record_flow_hash to
> _sock_rps_record_flow_hash, and add one helper func which checks the
> rfs_needed.
>
> The perf result of two functions is following.
> When rfs is disabled, it could enhance 58% performance with checking
> rfs_needed.
> When rfs is enabled, the performanc is lower than current about 29%.
>
> Because the RFS is disabled by default. I think it is useful to tun
> driver.
>
> The follow is test statistics.
> Signed-off-by: Gao Feng <gfree.w...@vip.163.com>
> ---
> include/net/sock.h | 12 ++++++++++--
> 1 file changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/include/net/sock.h b/include/net/sock.h
> index 3467d9e..584bb9a 100644
> --- a/include/net/sock.h
> +++ b/include/net/sock.h
> @@ -910,7 +910,7 @@ static inline void sk_incoming_cpu_update(struct sock *sk)
> sk->sk_incoming_cpu = raw_smp_processor_id();
> }
>
> -static inline void sock_rps_record_flow_hash(__u32 hash)
> +static inline void _sock_rps_record_flow_hash(__u32 hash)
> {
> #ifdef CONFIG_RPS
> struct rps_sock_flow_table *sock_flow_table;
> @@ -922,6 +922,14 @@ static inline void sock_rps_record_flow_hash(__u32 hash)
> #endif
> }
>
> +static inline void sock_rps_record_flow_hash(__u32 hash)
> +{
> +#ifdef CONFIG_RPS
> + if (static_key_false(&rfs_needed))
> + _sock_rps_record_flow_hash(hash);
> +#endif
Seems that after your patch, sock_rps_record_flow_hash() is no longer
needed/used.
