On Fri, Apr 21, 2017 at 1:27 AM, Bala Manoharan <bala.manoha...@linaro.org> wrote:
> On 21 April 2017 at 02:05, Honnappa Nagarahalli > <honnappa.nagaraha...@linaro.org> wrote: > > On 20 April 2017 at 13:54, Bill Fischofer <bill.fischo...@linaro.org> > wrote: > >> > >> On Thu, Apr 20, 2017 at 12:26 PM, Honnappa Nagarahalli > >> <honnappa.nagaraha...@linaro.org> wrote: > >>> > >>> Hi, > >>> I looked at the shmem pool APIs for allocating smaller chunks of > >>> shared memory. Following are the APIs I am looking at: > >>> > >>> odpdrv_shm_pool_create > >>> odpdrv_shm_pool_destroy > >>> odpdrv_shm_pool_alloc > >>> odpdrv_shm_pool_free > >>> > >>> Few questions: > >>> > >>> 1) Why are these APIs prefixed with 'odpdrv', this should be 'odp'. > >>> Are these APIs supposed to be used only by drivers? > >> > >> > >> Christophe was using the prefix odpdrv_ for new "Southside" APIs. The > idea > >> is that the standard "Northside" (odp_ prefix) APIs are intended for > use by > >> applications to allow portability across different ODP implementations > while > >> the Southside APIs would provide the same sort of portability for > drivers. > >> These haven't been formalized (yet) so these are still under > definition. I > >> hope we'll be able to review / discuss these during the upcoming Sprint. > >> > >>> > >>> 2) odpdrv_shm_pool_alloc - does not take 'alignment' input. The > >>> scalable scheduler data structures need cache line alignment. > >> > >> > >> These are prototypes at this point and if that's needed I'm sure it > could > >> easily be added. Since drivers are typically dealing with page-aligned > ring > >> buffers and such they would automatically be cache-aligned, so perhaps > he > >> didn't see the need to call that out explicitly. > >> > > > > I find these APIs useful in allocating smaller chunks of shared memory > > (may be some more functionality can be added to these APIs). I will > > use them in the scalable scheduler for allocating shared memory for > > queues. > > Since these are driver APIs they might not be available in all > implementations. > IMO, we need to keep scalable scheduler implementation independent > from drv APIs. > Agree. Christophe developed his shm extensions with a view that they could be used by both north and south APIs. That's the reason why _ishm.c exists. Sounds like these should be made _ishm functions so that the scheduler can use them as internal APIs. > > Regards, > Bala > > > >>> > >>> > >>> Thanks, > >>> Honnappa > >> > >> >
