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

[Tvrtko Ursulin]

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))
>>> +		|| gem_has_guc_submission(fd));
>>> +}
>>> +
>>>    /**
>>>     * gem_scheduler_print_capability:
>>>     * @fd: open i915 drm file descriptor @@ -151,4 +168,8 @@ void
>>> gem_scheduler_print_capability(int fd)
>>>    		igt_info(" - With HW semaphores enabled\n");
>>>    	if (caps & I915_SCHEDULER_CAP_ENGINE_BUSY_STATS)
>>>    		igt_info(" - With engine busy statistics\n");
>>> +	if ((caps & (I915_SCHEDULER_CAP_PREEMPTION
>>> +		  | I915_SCHEDULER_CAP_SEMAPHORES))
>>> +		|| gem_has_guc_submission(fd))
>>> +		igt_info(" - With user timeslicing enabled\n");
>>
>> I don't think it's "user timeslicing" but just timeslicing. Otherwise looks okay.
> 
> I think this is what it was before, I have not changed print. Do you want to change it?

I don't care hugely. It is just not clear to me reader of this banner 
will have any idea what is "user timeslicing" versus just timeslicing.

Regards,

Tvrtko