[igt-dev] [i-g-t V3 1/2] lib/i915: find scheduler caps for timeslicing

[Petri Latvala]

On Thu, Jun 03, 2021 at 03:50:32PM +0100, Chris Wilson wrote:
> Quoting Tvrtko Ursulin (2021-06-01 11:24:00)
> > 
> > On 01/06/2021 11:10, Surendrakumar Upadhyay, TejaskumarX wrote:
> > >> -----Original Message-----
> > >> From: Tvrtko Ursulin <tvrtko.ursulin at linux.intel.com>
> > >> Sent: 01 June 2021 15:38
> > >> To: Surendrakumar Upadhyay, TejaskumarX
> > >> <tejaskumarx.surendrakumar.upadhyay at intel.com>; igt-
> > >> dev at lists.freedesktop.org
> > >> Subject: Re: [igt-dev] [i-g-t V3 1/2] lib/i915: find scheduler caps for timeslicing
> > >>
> > >>
> > >> On 31/05/2021 14:41, Tejas Upadhyay wrote:
> > >>> Check scheduler capability for timeslicing in appropriate way, which
> > >>> requires wrappers to be created for IGT.
> > >>>
> > >>> V3:
> > >>>       removed conditional error - petri
> > >>> V2: has_timeslice = has_semaphore && has_preemption ||
> > >>>       has_guc_submission - Tvrtko
> > >>>
> > >>> Signed-off-by: Tejas Upadhyay
> > >>> <tejaskumarx.surendrakumar.upadhyay at intel.com>
> > >>> ---
> > >>>    lib/i915/gem_scheduler.c | 21 +++++++++++++++++++++
> > >>>    lib/i915/gem_scheduler.h |  1 +
> > >>>    2 files changed, 22 insertions(+)
> > >>>
> > >>> diff --git a/lib/i915/gem_scheduler.c b/lib/i915/gem_scheduler.c index
> > >>> 184da843..f59c451f 100644
> > >>> --- a/lib/i915/gem_scheduler.c
> > >>> +++ b/lib/i915/gem_scheduler.c
> > >>> @@ -29,6 +29,7 @@
> > >>>    #include "ioctl_wrappers.h"
> > >>>
> > >>>    #include "i915/gem_scheduler.h"
> > >>> +#include "i915/gem_submission.h"
> > >>>
> > >>>    /**
> > >>>     * SECTION:gem_scheduler
> > >>> @@ -129,6 +130,22 @@ bool gem_scheduler_has_engine_busy_stats(int
> > >> fd)
> > >>>             I915_SCHEDULER_CAP_ENGINE_BUSY_STATS;
> > >>>    }
> > >>>
> > >>> +/**
> > >>> + * gem_scheduler_has_timeslicing:
> > >>> + * @fd: open i915 drm file descriptor
> > >>> + *
> > >>> + * Feature test macro to query whether the driver supports using HW
> > >>> +preemption
> > >>> + * to implement timeslicing of userspace batches. This allows
> > >>> +userspace to
> > >>> + * implement micro-level scheduling within their own batches.
> > >>> + */
> > >>> +bool gem_scheduler_has_timeslicing(int fd) {
> > >>> +   return ((gem_scheduler_capability(fd) &
> > >>> +           (I915_SCHEDULER_CAP_PREEMPTION |
> > >>> +            I915_SCHEDULER_CAP_SEMAPHORES))
> 
> This bitwise or is incorrect, both are required.

Yes, I had a brainfart and didn't spot it.


Revert inc.

-- 
Petri Latvala