[igt-dev] [PATCH i-g-t 2/2] 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.  To avoid object overlapping,
offsets need to be calculated with actual minimum batch size in mind.

Replace hardcoded constants corresponding to the assumed 4kB minimum
batch size with values calculated from a variable supposed to represent
actual batch size.  For now, the variable is still initialized with the
4kB value, 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 | 21 +++++++++++++--------
 1 file changed, 13 insertions(+), 8 deletions(-)

diff --git a/tests/i915/gem_exec_reloc.c b/tests/i915/gem_exec_reloc.c
index 8f88826e..8d2f10ac 100644
--- a/tests/i915/gem_exec_reloc.c
+++ b/tests/i915/gem_exec_reloc.c
@@ -518,16 +518,21 @@ static void basic_range(int fd, unsigned flags)
 	struct drm_i915_gem_execbuffer2 execbuf;
 	uint64_t address_mask = has_64b_reloc(fd) ? ~(uint64_t)0 : ~(uint32_t)0;
 	uint64_t gtt_size = gem_aperture_size(fd);
+	/* FIXME: switch to a suitable library function when available */
+	uint64_t batch_size = 4096;
 	const uint32_t bbe = MI_BATCH_BUFFER_END;
 	igt_spin_t *spin = NULL;
-	int count, n;
+	int batch_order, count, n;
 
 	igt_require(gem_has_softpin(fd));
 
-	for (count = 12; gtt_size >> (count + 1); count++)
+	for (batch_order = 0; batch_size >> (batch_order + 1); batch_order++)
 		;
 
-	count -= 12;
+	for (count = batch_order; gtt_size >> (count + 1); count++)
+		;
+
+	count -= batch_order;
 
 	memset(obj, 0, sizeof(obj));
 	memset(reloc, 0, sizeof(reloc));
@@ -535,8 +540,8 @@ 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].handle = gem_create(fd, batch_size);
+		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_ppgtt(fd)) {
@@ -556,8 +561,8 @@ static void basic_range(int fd, unsigned flags)
 		n++;
 	}
 	for (int i = 1; i < count; i++) {
-		obj[n].handle = gem_create(fd, 4096);
-		obj[n].offset = 1ull << (i + 12);
+		obj[n].handle = gem_create(fd, batch_size);
+		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_ppgtt(fd)) {
@@ -578,7 +583,7 @@ static void basic_range(int fd, unsigned flags)
 	}
 	igt_require(n);
 
-	obj[n].handle = gem_create(fd, 4096);
+	obj[n].handle = gem_create(fd, batch_size);
 	obj[n].relocs_ptr = to_user_pointer(reloc);
 	obj[n].relocation_count = n;
 	gem_write(fd, obj[n].handle, 0, &bbe, sizeof(bbe));
-- 
2.21.0