Re: [PATCH] Fix SMP support on 3c527 net driver

From: Felipe W Damasio (felipewd_at_terra.com.br)
Date: 08/31/03

  • Next message: Jeff Chua: "Re: [BUG] hda:end_request: I/O error, dev 03:00 (hda), sector 0" 
    Date:	Sun, 31 Aug 2003 13:50:30 -0300
To: Manfred Spraul <manfred@colorfullife.com>

            Hi Manfred,

    Manfred Spraul wrote:
    > Additionally, you must replace the sleep_on calls with wait_event, or an
    > open-coded wait queue: sleep_on is racy, it only works with cli().

            Oh, I didn't no that..

    > IMHO the right way to fix cli() is
    > - add a single spinlock to the driver or the device structure. Do not
    > forget the spin_lock_init().
    > - replace cli/sti with spin_lock_irqsave/spin_unlock_irqsave.

            Yes.

    > - Additionally acquire the spinlock in every interrupt handler (cli()
    > stops all interrupts, spinlocks only stop interrupt on the current cpu).
    > - check if there were recursive cli() calls. Fix them.
    > - replace all sleep_on calls with wait queue calls.
    > - check if there are any kmalloc or schedule calls in the area now under
    > the spinlock, and reorganize the code.

            But doesn't wait_queue call schedule()?

    > And please add a changelog entry that code was converted without testing.

            Ok.

            Thanks for your review, will work on those.

    Felipe 

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  • Next message: Jeff Chua: "Re: [BUG] hda:end_request: I/O error, dev 03:00 (hda), sector 0"

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