Re: [PATCH 1/2] sched: Add cond_resched_rcu_lock() helper

[Ingo Molnar <mingo@kernel.org>]

* Simon Horman <horms@verge.net.au> wrote:

> This is intended for use in loops which read data protected by RCU and may
> have a large number of iterations.  Such an example is dumping the list of
> connections known to IPVS: ip_vs_conn_array() and ip_vs_conn_seq_next().
> 
> As suggested by Eric Dumazet.
> 
> Cc: Eric Dumazet <eric.dumazet@gmail.com>
> Cc: Julian Anastasov <ja@ssi.bg>
> Signed-off-by: Simon Horman <horms@verge.net.au>
> ---
>  include/linux/sched.h | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/include/linux/sched.h b/include/linux/sched.h
> index e692a02..7eec4c7 100644
> --- a/include/linux/sched.h
> +++ b/include/linux/sched.h
> @@ -2787,3 +2787,12 @@ static inline unsigned long rlimit_max(unsigned int limit)
>  }
>  
>  #endif
> +
> +static void inline cond_resched_rcu_lock(void)
> +{
> +	if (need_resched()) {
> +		rcu_read_unlock();
> +		cond_resched();
> +		rcu_read_lock();
> +	}
> +}

Acked-by: Ingo Molnar <mingo@kernel.org>

	Ingo