linux-kernel - Re: [PATCH 13/13] workqueue: record global worker ID instead of pool ID in work->data when off-queue

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20130204214057.GG27963@mtj.dyndns.org>
Date:	Mon, 4 Feb 2013 13:40:57 -0800
From:	Tejun Heo <tj@...nel.org>
To:	Lai Jiangshan <laijs@...fujitsu.com>
Cc:	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 13/13] workqueue: record global worker ID instead of pool
 ID in work->data when off-queue

Hello,

On Fri, Feb 01, 2013 at 02:41:36AM +0800, Lai Jiangshan wrote:
> -	pool = worker_pool_by_id(pool_id);
> -	if (!pool)
> -		return NULL;
> +	rcu_read_lock();
> +	exec = idr_find(&worker_gwid_idr, worker_gwid);
>  
> -	spin_lock(&pool->lock);
> -	exec = find_worker_executing_work(pool, work);
>  	if (exec) {
> -		BUG_ON(pool != exec->pool);
> -		*worker = exec;
> -		return pool;
> +		pool = exec->pool;
> +		spin_lock(&pool->lock);
> +		if (exec->current_work == work &&
> +		    exec->current_func == work->func) {
> +			*worker = exec;
> +			rcu_read_unlock();
> +			return pool;
> +		}
> +		spin_unlock(&pool->lock);
>  	}
> -	spin_unlock(&pool->lock);
> +	rcu_read_unlock();

We're guaranteed to have irq disabled, why not use sched_rcu in
combination with synchronize_sched()?

Thanks.

-- 
tejun
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/