Re: [PATCH] workqueue: use "pool->cpu < 0" to stand for an unbound pool

[Lai Jiangshan <laijs@cn.fujitsu.com>]

Hi, Tejun

3.16-rc1 came out. Could you review the patches?

Thanks,
Lai

On 06/03/2014 03:31 PM, Lai Jiangshan wrote:
> There is a piece of sanity checks code in the put_unbound_pool().
> The meaning of this code is "if it is not an unbound pool, it will complain
> and return" IIUC. But the code uses "pool->flags & POOL_DISASSOCIATED"
> imprecisely due to a non-unbound pool may also have this flags.
> 
> We should use "pool->cpu < 0" to stand for an unbound pool, so we covert the
> code to it.
> 
> There is no strictly wrong if we still keep "pool->flags & POOL_DISASSOCIATED"
> here, but it is just a noise if we keep it:
>   1) we focus on "unbound" here, not "[dis]association".
>   2) "pool->cpu < 0" already implies "pool->flags & POOL_DISASSOCIATED".
> 
> Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
> ---
>  kernel/workqueue.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/kernel/workqueue.c b/kernel/workqueue.c
> index 90a0fa5..724ae35 100644
> --- a/kernel/workqueue.c
> +++ b/kernel/workqueue.c
> @@ -3457,7 +3457,7 @@ static void put_unbound_pool(struct worker_pool *pool)
>  		return;
>  
>  	/* sanity checks */
> -	if (WARN_ON(!(pool->flags & POOL_DISASSOCIATED)) ||
> +	if (WARN_ON(!(pool->cpu < 0)) ||
>  	    WARN_ON(!list_empty(&pool->worklist)))
>  		return;
>