[igt-dev] [RFC i-g-t] tests/xe/xe_evict: Check for memory availability

[Niranjana Vishwanathapura]

On Wed, Jul 05, 2023 at 03:54:27AM -0700, Kumar, Janga Rahul wrote:
>
>
>> -----Original Message-----
>> From: igt-dev <igt-dev-bounces at lists.freedesktop.org> On Behalf Of Niranjana
>> Vishwanathapura
>> Sent: 05 July 2023 02:36
>> To: igt-dev at lists.freedesktop.org
>> Cc: Hellstrom, Thomas <thomas.hellstrom at intel.com>
>> Subject: [igt-dev] [RFC i-g-t] tests/xe/xe_evict: Check for memory availability
>>
>> On systems with low system memory the subtests fail in various ways including
>> returning -ENOMEM, hanging, etc.
>> Ensure system has enough memory for the tests, otherwise skip it.
>
>Instead of skipping the tests, we can update the num_bo to fit in the available memory.

Thanks Rahul for the review.

Seems like num_bo is chosen based on vram size to exercise vram overcommit.
But there may not be enough system memory to evict all vram BOs.
Hence, we need to skip the test.

>
>>
>> Signed-off-by: Niranjana Vishwanathapura
>> <niranjana.vishwanathapura at intel.com>
>> ---
>>  tests/xe/xe_evict.c | 42 ++++++++++++++++++++++++++++--------------
>>  1 file changed, 28 insertions(+), 14 deletions(-)
>>
>> diff --git a/tests/xe/xe_evict.c b/tests/xe/xe_evict.c index
>> 1a70f1b45..d28400f1c 100644
>> --- a/tests/xe/xe_evict.c
>> +++ b/tests/xe/xe_evict.c
>> @@ -454,6 +454,13 @@ static uint64_t calc_bo_size(uint64_t vram_size, int
>> mul, int div)
>>  	return (ALIGN(vram_size, 0x40000000)  * mul) / div;  }
>>
>> +static bool has_required_memory(uint64_t mem_size, uint64_t vram_size,
>> +				int num_bos, uint64_t bo_size)
>> +{
>> +	/* Assume 1/2 of system memory is available to use */
>> +	return (mem_size / 2 + vram_size) >= (num_bos * bo_size); }
>I think here available VRAM size for use needs to considered instead of total VRAM size.
>

The issue seems to be not the VRAM size, but the available system memory size (mem_size)
may not be enough to evict all the VRAM bos.

Niranjana

>Thanks,
>Rahul
>> +
>>  /**
>>   * SUBTEST: evict-%s
>>   * Description:  %arg[1] evict test.
>> @@ -658,12 +665,13 @@ igt_main
>>  			MIXED_THREADS | MULTI_VM | THREADED |
>> BIND_ENGINE },
>>  		{ NULL },
>>  	};
>> -	uint64_t vram_size;
>> +	uint64_t mem_size, vram_size;
>>  	int fd;
>>
>>  	igt_fixture {
>>  		fd = drm_open_driver(DRIVER_XE);
>>  		igt_require(xe_has_vram(fd));
>> +		mem_size = igt_get_total_ram_mb() << 20;
>>  		vram_size = xe_vram_size(fd, 0);
>>  		igt_assert(vram_size);
>>
>> @@ -673,25 +681,31 @@ igt_main
>>  	}
>>
>>  	for (const struct section *s = sections; s->name; s++) {
>> -		igt_subtest_f("evict-%s", s->name)
>> -			test_evict(-1, hwe, s->n_engines, s->n_execs,
>> -				   calc_bo_size(vram_size, s->mul, s->div),
>> -				   s->flags, NULL);
>> +		igt_subtest_f("evict-%s", s->name) {
>> +			uint64_t bo_size = calc_bo_size(vram_size, s->mul, s-
>> >div);
>> +
>> +			igt_require(has_required_memory(mem_size,
>> vram_size, s->n_execs / 2, bo_size));
>> +			test_evict(-1, hwe, s->n_engines, s->n_execs, bo_size,
>> s->flags, NULL);
>> +		}
>>  	}
>>
>>  	for (const struct section_cm *s = sections_cm; s->name; s++) {
>> -		igt_subtest_f("evict-%s", s->name)
>> -			test_evict_cm(-1, hwe, s->n_engines, s->n_execs,
>> -				      calc_bo_size(vram_size, s->mul, s->div),
>> -				      s->flags, NULL);
>> +		igt_subtest_f("evict-%s", s->name) {
>> +			uint64_t bo_size = calc_bo_size(vram_size, s->mul, s-
>> >div);
>> +
>> +			igt_require(has_required_memory(mem_size,
>> vram_size, s->n_execs / 2, bo_size));
>> +			test_evict(-1, hwe, s->n_engines, s->n_execs, bo_size,
>> s->flags, NULL);
>> +		}
>>  	}
>>
>>  	for (const struct section_threads *s = sections_threads; s->name; s++) {
>> -		igt_subtest_f("evict-%s", s->name)
>> -			threads(-1, hwe, s->n_threads, s->n_engines,
>> -				 s->n_execs,
>> -				 calc_bo_size(vram_size, s->mul, s->div),
>> -				 s->flags);
>> +		igt_subtest_f("evict-%s", s->name) {
>> +			uint64_t bo_size = calc_bo_size(vram_size, s->mul, s-
>> >div);
>> +
>> +			igt_require(has_required_memory(mem_size,
>> vram_size,
>> +							s->n_threads * (s-
>> >n_execs / 2), bo_size));
>> +			threads(-1, hwe, s->n_threads, s->n_engines, s-
>> >n_execs, bo_size, s->flags);
>> +		}
>>  	}
>>
>>  	igt_fixture
>> --
>> 2.21.0.rc0.32.g243a4c7e27
>