RE: [PATCH] ACPICA: Export mutex functions

Moore, Robert
2017-04-14T23:32:53Z

> -----Original Message-----
> From: Rafael J. Wysocki [mailto:rjw@rjwysocki.net]
> Sent: Friday, April 14, 2017 3:30 PM
> To: Moore, Robert
> Cc: Guenter Roeck; Zheng, Lv; Wysocki, Rafael J; Len Brown; linux-
> acpi@vger.kernel.org; devel@acpica.org; linux-kernel@vger.kernel.org
> Subject: Re: [PATCH] ACPICA: Export mutex functions
>
> On Wednesday, April 12, 2017 09:56:37 PM Moore, Robert wrote:
> >
> > > -----Original Message-----
> > > From: Guenter Roeck [mailto:linux@roeck-us.net]
> > > Sent: Wednesday, April 12, 2017 2:23 PM
> > > To: Moore, Robert <robert.moore@intel.com>
> > > Cc: Zheng, Lv <lv.zheng@intel.com>; Wysocki, Rafael J
> > > <rafael.j.wysocki@intel.com>; Len Brown <lenb@kernel.org>; linux-
> > > acpi@vger.kernel.org; devel@acpica.org; linux-kernel@vger.kernel.org
> > > Subject: Re: [PATCH] ACPICA: Export mutex functions
> > >
> > > On Wed, Apr 12, 2017 at 03:29:55PM +0000, Moore, Robert wrote:
> > > > The ACPICA mutex functions are based on the host OS functions, so
> > > > they
> > > don't really buy you anything. You should just use the native Linux
> > > functions.
> > > >
> > >
> > > You mean they don't really acquire the requested ACPI mutex, and the
> > > underlying DSDT which declares and uses the mutex just ignores if
> > > the mutex was acquired by acpi_acquire_mutex() ?
> > >
> > [Moore, Robert]
> >
> > OK, I understand now. Yes, these mutex interfaces are in fact intended
> for the purpose you mention:
> >
> > * FUNCTION: AcpiAcquireMutex
> > *
> > * PARAMETERS: Handle - Mutex or prefix handle (optional)
> > * Pathname - Mutex pathname (optional)
> > * Timeout - Max time to wait for the lock
> (millisec)
> > *
> > * RETURN: Status
> > *
> > * DESCRIPTION: Acquire an AML mutex. This is a device driver interface
> to
> > * AML mutex objects, and allows for transaction locking
> between
> > * drivers and AML code. The mutex node is pointed to by
> > * Handle:Pathname. Either Handle or Pathname can be NULL,
> but
> > * not both.
> >
> >
> > And yes, both the acquire and release interfaces should be exported.
>
> OK, so I'm assuming this will go in through the upstream ACPICA.
>

Yes, done for next release.
Bob

> Thanks,
> Rafael