Re: locking in a device driver

From: Dinesh Nair (dinesh_at_alphaque.com)
Date: 10/28/05

  • Next message: Mark Kirkwood: "Display files currently in the buffer cache" 
    Date: Fri, 28 Oct 2005 21:58:42 +0800
To: Scott Long <scottl@samsco.org>

    On 10/27/05 22:00 Scott Long said the following:
    > If you need to protect your pseudodriver from being interrupted by the
    > real driver then you'll need to use the same spl() as the driver. Note
    > that you shouldn't be using splhigh() unless you really know what you

    the driver currently is set to use INTR_TYPE_MISC, which from my
    understanding can only be masked with splhigh(). using another INTR_TYPE
    may be possible, so this is something i can explore.

    however, the device interrupts at a constant 1000Hz, as it's a quad-span
    E1/T1 line card, and thus it needs to have that interrupt serviced pronto
    to avoid E1/T1 frame slips. any advice here ? 

    -- 
Regards,                           /\_/\   "All dogs go to heaven."
dinesh@alphaque.com                (0 0)    http://www.alphaque.com/
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  • Next message: Mark Kirkwood: "Display files currently in the buffer cache"

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