Messages in this thread | | | From | Oliver Neukum <> | Subject | Re: [PATCH] Replace completions with semaphores | Date | Wed, 16 Apr 2008 18:42:50 +0200 |
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Am Mittwoch, 16. April 2008 18:34:14 schrieb Matthew Wilcox: > On Wed, Apr 16, 2008 at 06:31:08PM +0200, Oliver Neukum wrote: > > Am Mittwoch, 16. April 2008 18:16:52 schrieb Matthew Wilcox: > > > The basic idea is that you get back a cookie from the kcounter_claim() > > > which you have to hand to the kcounter_release() function so it > > > knows which one you released. ?It's similar to mutex debugging except > > > > So in addition to the kcounter we need to save a token in a data structure? > > In fact, there must be a data structure that can house that token. So you > > can no longer live with a pointer just to a device descriptor, but every > > individual use of a resource must have an associated data structure? > > That's right. Do you have an example where this would be inconvenient? > I couldn't find one. For example, with USB, you could place one in the > struct urb.
That's a data structure we really want to shrink. And furthermore, the needs of the use cases should shape the locking primitives, not the reverse.
Regards Oliver
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