[Intel-gfx] [PATCH] drm/i915/selftests: Refactor sibling selection

[Tvrtko Ursulin]

On 18/05/2020 11:29, Chris Wilson wrote:
> Tvrtko spotted that some selftests were using 'break' not 'continue',
> which will fail for discontiguous engine layouts such as on Icelake
> (which may have vcs0 and vcs2).
> 
> Reported-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> ---
>   drivers/gpu/drm/i915/gt/selftest_lrc.c | 68 ++++++++++----------------
>   1 file changed, 27 insertions(+), 41 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/gt/selftest_lrc.c b/drivers/gpu/drm/i915/gt/selftest_lrc.c
> index 824f99c4cc7c..94854a467e66 100644
> --- a/drivers/gpu/drm/i915/gt/selftest_lrc.c
> +++ b/drivers/gpu/drm/i915/gt/selftest_lrc.c
> @@ -3600,13 +3600,30 @@ static int nop_virtual_engine(struct intel_gt *gt,
>   	return err;
>   }
>   
> +static unsigned int select_siblings(struct intel_gt *gt,
> +				    unsigned int class,
> +				    struct intel_engine_cs **siblings)
> +{
> +	unsigned int n = 0;
> +	unsigned int inst;
> +
> +	for (inst = 0; inst <= MAX_ENGINE_INSTANCE; inst++) {
> +		if (!gt->engine_class[class][inst])
> +			continue;
> +
> +		siblings[n++] = gt->engine_class[class][inst];
> +	}
> +
> +	return n;
> +}
> +
>   static int live_virtual_engine(void *arg)
>   {
>   	struct intel_gt *gt = arg;
>   	struct intel_engine_cs *siblings[MAX_ENGINE_INSTANCE + 1];
>   	struct intel_engine_cs *engine;
>   	enum intel_engine_id id;
> -	unsigned int class, inst;
> +	unsigned int class;
>   	int err;
>   
>   	if (intel_uc_uses_guc_submission(&gt->uc))
> @@ -3624,13 +3641,7 @@ static int live_virtual_engine(void *arg)
>   	for (class = 0; class <= MAX_ENGINE_CLASS; class++) {
>   		int nsibling, n;
>   
> -		nsibling = 0;
> -		for (inst = 0; inst <= MAX_ENGINE_INSTANCE; inst++) {
> -			if (!gt->engine_class[class][inst])
> -				continue;
> -
> -			siblings[nsibling++] = gt->engine_class[class][inst];
> -		}
> +		nsibling = select_siblings(gt, class, siblings);
>   		if (nsibling < 2)
>   			continue;
>   
> @@ -3739,7 +3750,7 @@ static int live_virtual_mask(void *arg)
>   {
>   	struct intel_gt *gt = arg;
>   	struct intel_engine_cs *siblings[MAX_ENGINE_INSTANCE + 1];
> -	unsigned int class, inst;
> +	unsigned int class;
>   	int err;
>   
>   	if (intel_uc_uses_guc_submission(&gt->uc))
> @@ -3748,13 +3759,7 @@ static int live_virtual_mask(void *arg)
>   	for (class = 0; class <= MAX_ENGINE_CLASS; class++) {
>   		unsigned int nsibling;
>   
> -		nsibling = 0;
> -		for (inst = 0; inst <= MAX_ENGINE_INSTANCE; inst++) {
> -			if (!gt->engine_class[class][inst])
> -				break;
> -
> -			siblings[nsibling++] = gt->engine_class[class][inst];
> -		}
> +		nsibling = select_siblings(gt, class, siblings);
>   		if (nsibling < 2)
>   			continue;
>   
> @@ -3876,7 +3881,7 @@ static int live_virtual_preserved(void *arg)
>   {
>   	struct intel_gt *gt = arg;
>   	struct intel_engine_cs *siblings[MAX_ENGINE_INSTANCE + 1];
> -	unsigned int class, inst;
> +	unsigned int class;
>   
>   	/*
>   	 * Check that the context image retains non-privileged (user) registers
> @@ -3894,13 +3899,7 @@ static int live_virtual_preserved(void *arg)
>   	for (class = 0; class <= MAX_ENGINE_CLASS; class++) {
>   		int nsibling, err;
>   
> -		nsibling = 0;
> -		for (inst = 0; inst <= MAX_ENGINE_INSTANCE; inst++) {
> -			if (!gt->engine_class[class][inst])
> -				continue;
> -
> -			siblings[nsibling++] = gt->engine_class[class][inst];
> -		}
> +		nsibling = select_siblings(gt, class, siblings);
>   		if (nsibling < 2)
>   			continue;
>   
> @@ -4111,7 +4110,7 @@ static int live_virtual_bond(void *arg)
>   	};
>   	struct intel_gt *gt = arg;
>   	struct intel_engine_cs *siblings[MAX_ENGINE_INSTANCE + 1];
> -	unsigned int class, inst;
> +	unsigned int class;
>   	int err;
>   
>   	if (intel_uc_uses_guc_submission(&gt->uc))
> @@ -4121,14 +4120,7 @@ static int live_virtual_bond(void *arg)
>   		const struct phase *p;
>   		int nsibling;
>   
> -		nsibling = 0;
> -		for (inst = 0; inst <= MAX_ENGINE_INSTANCE; inst++) {
> -			if (!gt->engine_class[class][inst])
> -				break;
> -
> -			GEM_BUG_ON(nsibling == ARRAY_SIZE(siblings));
> -			siblings[nsibling++] = gt->engine_class[class][inst];
> -		}
> +		nsibling = select_siblings(gt, class, siblings);
>   		if (nsibling < 2)
>   			continue;
>   
> @@ -4266,7 +4258,7 @@ static int live_virtual_reset(void *arg)
>   {
>   	struct intel_gt *gt = arg;
>   	struct intel_engine_cs *siblings[MAX_ENGINE_INSTANCE + 1];
> -	unsigned int class, inst;
> +	unsigned int class;
>   
>   	/*
>   	 * Check that we handle a reset event within a virtual engine.
> @@ -4284,13 +4276,7 @@ static int live_virtual_reset(void *arg)
>   	for (class = 0; class <= MAX_ENGINE_CLASS; class++) {
>   		int nsibling, err;
>   
> -		nsibling = 0;
> -		for (inst = 0; inst <= MAX_ENGINE_INSTANCE; inst++) {
> -			if (!gt->engine_class[class][inst])
> -				continue;
> -
> -			siblings[nsibling++] = gt->engine_class[class][inst];
> -		}
> +		nsibling = select_siblings(gt, class, siblings);
>   		if (nsibling < 2)
>   			continue;
>   
> 

Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>

Regards,

Tvrtko