I wrote:
> The only fast path that needs atomic_dec_if_positive is down_trylock.
> You can use atomic_dec for down_trylock instead; the only downside to
> that is that if somebody was holding the semaphore but nobody was
> waiting, the holder will take the slow path when it does the up.
Better st
Benjamin LaHaise writes:
> There are at least two users who need asynchronous semaphore/mutex
> operations: aio_write (which needs to acquire i_sem), and nfs.
What do you mean by asynchronous semaphore/mutex operations? Are you
talking about a down operation that will acquire the semaphore if
Trond Myklebust writes:
> The PPC implementation would be hard to port to x86, since it relies on
> the load-linked/store-conditional stuff to provide a fast primitive for
> atomic_dec_if_positive().
The only fast path that needs atomic_dec_if_positive is down_trylock.
You can use atomic_dec for
fr den 29.04.2005 Klokka 10:14 (-0400) skreiv Benjamin LaHaise:
> On Fri, Apr 29, 2005 at 10:44:17AM +1000, Paul Mackerras wrote:
> > You have made semaphores bigger and slower on the architectures that
> > have load-linked/store-conditional instructions, which is at least
> > ppc, ppc64, sparc64 a
On Fri, Apr 29, 2005 at 10:44:17AM +1000, Paul Mackerras wrote:
> You have made semaphores bigger and slower on the architectures that
> have load-linked/store-conditional instructions, which is at least
> ppc, ppc64, sparc64 and alpha. Did you take the trouble to understand
> the ppc semaphore im
5 matches
Mail list logo
