Re: [PATCH] as i/o hang with aacraid driver 2.6.0-test1

From: Nick Piggin <piggin@cyberone.com.au>
To: Jens Axboe <axboe@suse.de>
Cc: Andrew Morton <akpm@osdl.org>,
	James.Bottomley@steeleye.com, markh@osdl.org, cliffw@osdl.org,
	linux-scsi@vger.kernel.org
Subject: Re: [PATCH] as i/o hang with aacraid driver 2.6.0-test1
Date: Thu, 17 Jul 2003 21:21:51 +1000	[thread overview]
Message-ID: <3F1686CF.70201@cyberone.com.au> (raw)
In-Reply-To: <20030717111043.GH833@suse.de>

Jens Axboe wrote:

>On Thu, Jul 17 2003, Nick Piggin wrote:
>
>>
>>Jens Axboe wrote:
>>
>>
>>>On Thu, Jul 17 2003, Nick Piggin wrote:
>>>
>>>
>>>>If the requeue were seperate to the add, it would simply be a call
>>>>to as_completed_request in as-iosched.c.
>>>>
>>>>
>>>Out of laziness, or what? Just the accounting, not the actual completion
>>>bits.
>>>
>>>
>>Well no it would have to because it has nothing to associate
>>the re-add with a re-add and not a new add, if you know what
>>I mean.
>>
>>So it would have to do all the cleanup stuff that
>>as_completed_request does. Its possible I guess, that we could
>>set a flag in the as_rq's state field, to say that the request
>>is a re-add, but thats not very clean IMO.
>>
>
>Wont that possibly cause it to make bad decisions? From AS pov, it looks
>like an immediate complete of a request. Which it isn't.
>

Yeah thats correct - AS assumes elv_add_request is an entirely new
request from the process point of view, so yeah the quick fix wasn't
entirely optimal for AS.