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Date: Thu, 13 Nov 2003 11:52:23 +0100
From: Jens Axboe <axboe@suse.de>
To: Nick Piggin <piggin@cyberone.com.au>,
       Linux Kernel <linux-kernel@vger.kernel.org>
Cc: Linus Torvalds <torvalds@osdl.org>
Subject: Re: AS spin lock bugs
Message-ID: <20031113105223.GC4441@suse.de>
References: <20031113103823.GB4441@suse.de>
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On Thu, Nov 13 2003, Jens Axboe wrote:
> @@ -959,12 +960,12 @@
>  	if (!aic)
>  		return;
>  
> -	spin_lock(&aic->lock);
> +	spin_lock_irqsave(&aic->lock, flags);
>  	if (arq->is_sync == REQ_SYNC) {
>  		set_bit(AS_TASK_IORUNNING, &aic->state);
>  		aic->last_end_request = jiffies;
>  	}
> -	spin_unlock(&aic->lock);
> +	spin_unlock_irqrestore(&aic->lock, flags);
>  
>  	put_io_context(arq->io_context);
>  }

BTW, this looks bogus. Why do you need any locking there?

-- 
Jens Axboe