Re: [PATCH 4/4] acpi: semaphore removal

Matthew Wilcox
2008-08-26T19:52:41Z

On Tue, Aug 26, 2008 at 12:30:46PM -0700, Daniel Walker wrote:
> On Tue, 2008-08-26 at 13:13 -0600, Matthew Wilcox wrote:
> > On Tue, Aug 26, 2008 at 11:59:49AM -0700, Daniel Walker wrote:
> > > The semaphore usage in ACPI is more like completions. The ASL
> >
> > Huh? They are semaphores. They're not 'more like completions' at all.
>
> You can clearly make a completion out of a semaphore, but we have a
> completion API .. ACPI is using locked semaphores, and essentially
> re-making completions with the semaphore API..

What makes you think that?

executer/excreate.c: status = acpi_os_create_semaphore(ACPI_NO_UNIT_LIMIT, 0,
executer/exsystem.c: acpi_os_create_semaphore(ACPI_NO_UNIT_LIMIT, 0, &temp_semaphore);
namespace/nsaccess.c: acpi_os_create_semaphore(1, 0,
osl.c:acpi_os_create_semaphore(u32 max_units, u32 initial_units, acpi_handle * handle)

All users set 'initial_units' to 0.

--
Matthew Wilcox Intel Open Source Technology Centre
"Bill, look, we understand that you're interested in selling us this
operating system, but compare it to ours. We can't possibly take such
a retrograde step."