Messages in this thread | | | Date | Wed, 30 Jun 2010 12:54:57 +0100 | From | "Jan Beulich" <> | Subject | Re: [PATCH 1/4, v2] x86: enlightenment for ticket spin locks - base implementation |
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>>> On 30.06.10 at 13:48, Peter Zijlstra <peterz@infradead.org> wrote: > On Wed, 2010-06-30 at 12:43 +0100, Jan Beulich wrote: > >> It does tickle just the new owner - that's what the list is for. > > But if you have a FIFO list you don't need the ticket stuff and can > implement a FIFO lock instead.
The list is LIFO (not FIFO, as only the most recently added entry is a candidate for needing wakeup as long as there's no interrupt re-enabling in irqsave lock paths), and is only used for tickling (not for deciding who's going to be the next owner).
Jan
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