Re: [Intel-gfx] [PATCH] drm/i915/gem: Fix the mman selftest

["Thomas Hellström" <thomas.hellstrom@linux.intel.com>]

On 8/31/21 11:45 AM, Maarten Lankhorst wrote:
> Op 26-08-2021 om 09:24 schreef Thomas Hellström:
>> Using the I915_MMAP_TYPE_FIXED mmap type requires the TTM backend, so
>> for that mmap type, use __i915_gem_object_create_user() instead of
>> i915_gem_object_create_internal(), as we really want to tests objects
>> mmap-able by user-space.
>>
>> This also means that the out-of-space error happens at object creation
>> and returns -ENXIO rather than -ENOSPC, so fix the code up to expect
>> that on out-of-offset-space errors.
>>
>> Finally only use I915_MMAP_TYPE_FIXED for LMEM and SMEM for now if
>> testing on LMEM-capable devices. For stolen LMEM, we still take the
>> same path as for integrated, as that haven't been moved over to TTM yet,
>> and user-space should not be able to create out of stolen LMEM anyway.
>>
>> Fixes: 7961c5b60f23 ("drm/i915: Add TTM offset argument to mmap.")
>> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
>> Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
>> ---
>>   .../drm/i915/gem/selftests/i915_gem_mman.c    | 26 +++++++++++++++----
>>   1 file changed, 21 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c
>> index b20f5621f62b..68da25e66b69 100644
>> --- a/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c
>> +++ b/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c
>> @@ -581,6 +581,20 @@ static enum i915_mmap_type default_mapping(struct drm_i915_private *i915)
>>   	return I915_MMAP_TYPE_GTT;
>>   }
>>   
>> +static struct drm_i915_gem_object *
>> +create_sys_or_internal(struct drm_i915_private *i915,
>> +		       unsigned long size)
>> +{
>> +	if (HAS_LMEM(i915)) {
>> +		struct intel_memory_region *sys_region =
>> +			i915->mm.regions[INTEL_REGION_SMEM];
>> +
>> +		return __i915_gem_object_create_user(i915, size, &sys_region, 1);
>> +	}
>> +
>> +	return i915_gem_object_create_internal(i915, size);
>> +}
>> +
>>   static bool assert_mmap_offset(struct drm_i915_private *i915,
>>   			       unsigned long size,
>>   			       int expected)
>> @@ -589,7 +603,7 @@ static bool assert_mmap_offset(struct drm_i915_private *i915,
>>   	u64 offset;
>>   	int ret;
>>   
>> -	obj = i915_gem_object_create_internal(i915, size);
>> +	obj = create_sys_or_internal(i915, size);
>>   	if (IS_ERR(obj))
>>   		return expected && expected == PTR_ERR(obj);
>>   
>> @@ -633,6 +647,7 @@ static int igt_mmap_offset_exhaustion(void *arg)
>>   	struct drm_mm_node *hole, *next;
>>   	int loop, err = 0;
>>   	u64 offset;
>> +	int enospc = HAS_LMEM(i915) ? -ENXIO : -ENOSPC;
>>   
>>   	/* Disable background reaper */
>>   	disable_retire_worker(i915);
>> @@ -683,14 +698,14 @@ static int igt_mmap_offset_exhaustion(void *arg)
>>   	}
>>   
>>   	/* Too large */
>> -	if (!assert_mmap_offset(i915, 2 * PAGE_SIZE, -ENOSPC)) {
>> +	if (!assert_mmap_offset(i915, 2 * PAGE_SIZE, enospc)) {
>>   		pr_err("Unexpectedly succeeded in inserting too large object into single page hole\n");
>>   		err = -EINVAL;
>>   		goto out;
>>   	}
>>   
>>   	/* Fill the hole, further allocation attempts should then fail */
>> -	obj = i915_gem_object_create_internal(i915, PAGE_SIZE);
>> +	obj = create_sys_or_internal(i915, PAGE_SIZE);
>>   	if (IS_ERR(obj)) {
>>   		err = PTR_ERR(obj);
>>   		pr_err("Unable to create object for reclaimed hole\n");
>> @@ -703,7 +718,7 @@ static int igt_mmap_offset_exhaustion(void *arg)
>>   		goto err_obj;
>>   	}
>>   
>> -	if (!assert_mmap_offset(i915, PAGE_SIZE, -ENOSPC)) {
>> +	if (!assert_mmap_offset(i915, PAGE_SIZE, enospc)) {
>>   		pr_err("Unexpectedly succeeded in inserting object into no holes!\n");
>>   		err = -EINVAL;
>>   		goto err_obj;
>> @@ -842,7 +857,8 @@ static bool can_mmap(struct drm_i915_gem_object *obj, enum i915_mmap_type type)
>>   	struct drm_i915_private *i915 = to_i915(obj->base.dev);
>>   	bool no_map;
>>   
>> -	if (HAS_LMEM(i915))
>> +	if (HAS_LMEM(i915) && (obj->mm.region->id == INTEL_REGION_SMEM ||
>> +			       obj->mm.region->id == INTEL_REGION_LMEM))
> Ooh just noticed, make the whole line "if (obj->ops->mmap_offset)" instead to match i915_gem_mman.c?

Ah, right. I'll fix that up.

/Thomas

>
> Otherwise looks good.
>
> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
>
>>   		return type == I915_MMAP_TYPE_FIXED;
>>   	else if (type == I915_MMAP_TYPE_FIXED)
>>   		return false;
>