Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 21 Mar 2000 13:40:20 -0800
From:      Mike Smith <msmith@freebsd.org>
To:        Matthew Dillon <dillon@apollo.backplane.com>
Cc:        Brad Knowles <blk@skynet.be>, "John W. DeBoskey" <jwd@unx.sas.com>, freebsd-current@FreeBSD.ORG, Brad Chisholm <sasblc@unx.sas.com>
Subject:   Re: AMI MegaRAID lockup? not accepting commands. 
Message-ID:  <200003212140.NAA00925@mass.cdrom.com>
In-Reply-To: Your message of "Tue, 21 Mar 2000 09:14:14 PST." <200003211714.JAA81010@apollo.backplane.com> 

next in thread | previous in thread | raw e-mail | index | archive | help
> :At 7:25 PM -0800 2000/3/20, Mike Smith wrote:
> :
> :>  Not that I consider this particuarly optimal; busy-waiting for the
> :>  controller is a terrible waste of the host CPU.  A better solution would
> :>  probably defer the command and try again a short time later, but let's
> :>  see if this works first.
> :
> :	Since this is a device driver, I guess you can't usleep() and 
> :then check again?  Is there anything else useful you could be doing 
> :during that period of time -- other than busy waiting?
> 
>     For situations that aren't in the critical path and don't happen often,
>     it may be beneficial to do a voluntary context switch inside the loop.

Is it possible/legal to do this inside a strategy() routine?

-- 
\\ Give a man a fish, and you feed him for a day. \\  Mike Smith
\\ Tell him he should learn how to fish himself,  \\  msmith@freebsd.org
\\ and he'll hate you for a lifetime.             \\  msmith@cdrom.com




To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-current" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200003212140.NAA00925>