Messages in this thread | | | Date | Mon, 12 Mar 2001 19:05:27 +0100 | From | Jamie Lokier <> | Subject | Re: static scheduling - SCHED_IDLE? |
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Adrian Cox wrote: > Unfortunately the kernel is already full of counting semaphores. > Priority inheritance won't save you, as the task which is going to call > up() need not be the same one that called down(). > > Jamie Lokier's suggestion of raising priority when in the kernel doesn't > help. You need to raise the priority of the task which is currently in > userspace and will call up() next time it enters the kernel. You don't > know which task that is.
Dear oh dear. I was under the impression that kernel semaphores are supposed to be used as mutexes only -- there are other mechanisms for signalling between processes.
Do any processes ever enter userspace holding a critical semaphore?
(Things like userspace signalling another userspace don't count -- it's your own fault and your own problem if _that_ deadlocks).
-- Jamie - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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