[igt-dev] [RFC PATCH v2 2/3] tests/gem_exec_reloc: Calculate softpin offsets from batch size

[Janusz Krzysztofik]

From: Janusz Krzysztofik <janusz.krzysztofik at intel.com>

The basic-range subtest assumes 4kB minimum batch size.  On future
backends with possibly bigger minimum batch sizes this subtest will
fail as buffer objects may overlap on softpin.  To avoid object
overlapping, softpin offsets need to be calculated with actual minimum
batch size in mind.

Replace hardcoded constants corresponding to the assumed 4kB value with
variables supposed to reflect actual batch size.  For now, the
variables are still initialized with values specific to the 4kB minimum
batch size, which are suitable for backends currently supported by IGT.

Signed-off-by: Janusz Krzysztofik <janusz.krzysztofik at intel.com>
Cc: Katarzyna Dec <katarzyna.dec at intel.com>
Cc: Stuart Summers <stuart.summers at intel.com>
---
 tests/i915/gem_exec_reloc.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/tests/i915/gem_exec_reloc.c b/tests/i915/gem_exec_reloc.c
index f7fc0ea7..61401ea7 100644
--- a/tests/i915/gem_exec_reloc.c
+++ b/tests/i915/gem_exec_reloc.c
@@ -520,14 +520,16 @@ static void basic_range(int fd, unsigned flags)
 	uint64_t gtt_size = gem_aperture_size(fd);
 	const uint32_t bbe = MI_BATCH_BUFFER_END;
 	igt_spin_t *spin = NULL;
+	int batch_order = 12;
+	uint64_t batch_size = 1ull << batch_order; /* 4096 */
 	int count, n;
 
 	igt_require(gem_has_softpin(fd));
 
-	for (count = 12; gtt_size >> (count + 1); count++)
+	for (count = batch_order; gtt_size >> (count + 1); count++)
 		;
 
-	count -= 12;
+	count -= batch_order;
 
 	memset(obj, 0, sizeof(obj));
 	memset(reloc, 0, sizeof(reloc));
@@ -536,7 +538,7 @@ static void basic_range(int fd, unsigned flags)
 	n = 0;
 	for (int i = 0; i <= count; i++) {
 		obj[n].handle = gem_create(fd, 4096);
-		obj[n].offset = (1ull << (i + 12)) - 4096;
+		obj[n].offset = (1ull << (i + batch_order)) - batch_size;
 		obj[n].offset = gen8_canonical_address(obj[n].offset);
 		obj[n].flags = EXEC_OBJECT_PINNED | EXEC_OBJECT_SUPPORTS_48B_ADDRESS;
 		if (!gem_uses_full_ppgtt(fd)) {
@@ -557,7 +559,7 @@ static void basic_range(int fd, unsigned flags)
 	}
 	for (int i = 1; i < count; i++) {
 		obj[n].handle = gem_create(fd, 4096);
-		obj[n].offset = 1ull << (i + 12);
+		obj[n].offset = 1ull << (i + batch_order);
 		obj[n].offset = gen8_canonical_address(obj[n].offset);
 		obj[n].flags = EXEC_OBJECT_PINNED | EXEC_OBJECT_SUPPORTS_48B_ADDRESS;
 		if (!gem_uses_full_ppgtt(fd)) {
-- 
2.21.0