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SubjectRe: brlock_is_locked()?
On Wed, Aug 22 2001, Brad Chapman wrote:
> > (I checked the brlock code and didn't find any schedule()s; there's
> > probably a reason for that).
> >
> > Ummm, this is SMP 101, you can't sleep with a lock held.
> > The global kernel lock is special in this regard, but all
> > other SMP locking primitives may not sleep.
> Grrr....I read Rusty's Unreliable Guide to Kernel Locking (twice) and
> still didn't remember that. Guess you have to schedule() yourself.

Errr, like Dave said, _you cannot sleep while holding a lock_. It's not
just that the locking primitives themselves don't sleep, you must not
call schedule() (or any other function that may block/sleep) while
holding a lock. _That's_ SMP 101 :-)

Jens Axboe

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