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    SubjectRe: [PATCH] 2.5.3 remove global semaphore_lock spin lock.
    On Thu, Jan 31 2002, Jeff Garzik wrote:
    > On Thu, Jan 31, 2002 at 03:55:02PM -0800, Andrew Morton wrote:
    > > > + unsigned long flags;
    > > > + wq_write_lock_irqsave(&sem->wait.lock, flags);
    > > > - spin_lock_irq(&semaphore_lock);
    > >
    > > I rather dislike spin_lock_irq(), because it's fragile (makes
    > It's less flexible for architectures, too.
    > spin_lock_irqsave is considered 100% portable AFAIK, and I make it my
    > own policy to s/_irq/_irqsave/ when the opportunity strikes in my PCI
    > drivers.

    spin_lock_irq is cheaper, though, and sometimes you _know_ it's safe to
    use. For instance, if the function in question can block (ie never
    called with interrupts disabled) then using spin_lock_irq is always

    I've heard this portability argument before, anyone care to outline
    _what_ the problem allegedly is?? Major part of the kernel uses
    spin_lock_irq and I suspect we would be seeing lots of request list
    corruption did it not work.

    Jens Axboe

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