Factor in kernel object overhead when checking available memory for tests

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

5 files changed, 49 insertions, 17 deletions

diff --git a/lib/igt_aux.h b/lib/igt_aux.h
index 597580da..db0dea84 100644
--- a/lib/igt_aux.h
+++ b/lib/igt_aux.h
@@ -77,4 +77,8 @@ uint64_t intel_get_avail_ram_mb(void);
 uint64_t intel_get_total_ram_mb(void);
 uint64_t intel_get_total_swap_mb(void);
 
+bool intel_check_memory(uint32_t count, uint32_t size, unsigned mode);
+#define CHECK_RAM 0x1
+#define CHECK_SWAP 0x2
+
 #endif /* IGT_AUX_H */
diff --git a/lib/intel_os.c b/lib/intel_os.c
index 7d9a703a..e717c7b5 100644
--- a/lib/intel_os.c
+++ b/lib/intel_os.c
@@ -185,6 +185,36 @@ intel_get_total_swap_mb(void)
 	return retval / (1024*1024);
 }
 
+bool intel_check_memory(uint32_t count, uint32_t size, unsigned mode)
+{
+/* rough estimate of how many bytes the kernel requires to track each object */
+#define KERNEL_BO_OVERHEAD 512
+	uint64_t required, total;
+
+	required = count;
+	required *= size + KERNEL_BO_OVERHEAD;
+	required = ALIGN(required, 4096);
+
+	total = 0;
+	if (mode & (CHECK_RAM | CHECK_SWAP))
+		total += intel_get_avail_ram_mb();
+	if (mode & CHECK_SWAP)
+		total += intel_get_total_swap_mb();
+	total *= 1024 * 1024;
+
+	if (total <= required) {
+		igt_log(IGT_LOG_INFO,
+			"Estimated that we need %llu bytes for the test, but only have %llu bytes available (%s%s)\n",
+			(long long)required, (long long)total,
+			mode & CHECK_RAM ? "RAM" : "",
+			mode & CHECK_SWAP ? " + swap": "");
+		return 0;
+	}
+
+	return 1;
+}
+
+
 void
 intel_purge_vm_caches(void)
 {
diff --git a/tests/eviction_common.c b/tests/eviction_common.c
index 2d8e60ad..76cf26b8 100644
--- a/tests/eviction_common.c
+++ b/tests/eviction_common.c
@@ -101,13 +101,12 @@ static int minor_evictions(int fd, struct igt_eviction_test_ops *ops,
 }
 
 static int major_evictions(int fd, struct igt_eviction_test_ops *ops,
-				int surface_size, int nr_surfaces)
+			   int surface_size, int nr_surfaces)
 {
 	int n, m, loop;
 	uint32_t *bo;
 
-	igt_require((uint64_t)nr_surfaces * surface_size / (1024 * 1024)
-			< intel_get_total_ram_mb() * 9 / 10);
+	igt_require(intel_check_memory(nr_surfaces, surface_size, CHECK_RAM));
 
 	bo = malloc(nr_surfaces*sizeof(*bo));
 	igt_assert(bo);
@@ -128,19 +127,20 @@ static int major_evictions(int fd, struct igt_eviction_test_ops *ops,
 }
 
 static int swapping_evictions(int fd, struct igt_eviction_test_ops *ops,
-				int surface_size,
-				int working_surfaces,
-				int trash_surfaces)
+			      int surface_size,
+			      int working_surfaces,
+			      int trash_surfaces)
 {
 	uint32_t *bo;
 	int i, n, pass;
 
-	igt_require((uint64_t)working_surfaces * surface_size / (1024 * 1024)
-			< intel_get_total_ram_mb() * 9 / 10);
+	igt_require(intel_check_memory(working_surfaces, surface_size, CHECK_RAM));
 
 	if (trash_surfaces < working_surfaces)
 		trash_surfaces = working_surfaces;
 
+	igt_require(intel_check_memory(trash_surfaces, surface_size, CHECK_RAM | CHECK_SWAP));
+
 	bo = malloc(trash_surfaces*sizeof(*bo));
 	igt_assert(bo);
 
@@ -173,19 +173,18 @@ static int forking_evictions(int fd, struct igt_eviction_test_ops *ops,
 	int num_threads = sysconf(_SC_NPROCESSORS_ONLN);
 	int bo_count;
 
-	igt_require((uint64_t)working_surfaces * surface_size / (1024 * 1024)
-			< intel_get_total_ram_mb() * 9 / 10);
+	igt_require(intel_check_memory(working_surfaces, surface_size, CHECK_RAM));
 
 	if (flags & FORKING_EVICTIONS_SWAPPING) {
-		igt_require(intel_get_total_ram_mb() / 4
-				< intel_get_total_swap_mb());
 		bo_count = trash_surfaces;
-
 		if (bo_count < working_surfaces)
 			bo_count = working_surfaces;
+
 	} else
 		bo_count = working_surfaces;
 
+	igt_require(intel_check_memory(bo_count, surface_size, CHECK_RAM | CHECK_SWAP));
+
 	bo = malloc(bo_count*sizeof(*bo));
 	igt_assert(bo);
 
diff --git a/tests/gem_evict_everything.c b/tests/gem_evict_everything.c
index c595302e..6daf6c06 100644
--- a/tests/gem_evict_everything.c
+++ b/tests/gem_evict_everything.c
@@ -150,6 +150,7 @@ static void test_forking_evictions(int fd, int size, int count,
 	int trash_count;
 
 	trash_count = intel_get_total_ram_mb() * 11 / 10;
+	igt_require(intel_check_memory(trash_count, size, CHECK_RAM | CHECK_SWAP));
 
 	forking_evictions(fd, &fault_ops, size, count, trash_count, flags);
 }
@@ -158,9 +159,8 @@ static void test_swapping_evictions(int fd, int size, int count)
 {
 	int trash_count;
 
-	igt_require(intel_get_total_ram_mb() / 4 < intel_get_total_swap_mb());
-
 	trash_count = intel_get_total_ram_mb() * 11 / 10;
+	igt_require(intel_check_memory(trash_count, size, CHECK_RAM | CHECK_SWAP));
 
 	swapping_evictions(fd, &fault_ops, size, count, trash_count);
 }
diff --git a/tests/gem_tiled_swapping.c b/tests/gem_tiled_swapping.c
index 3bd2fa7e..86c79f2d 100644
--- a/tests/gem_tiled_swapping.c
+++ b/tests/gem_tiled_swapping.c
@@ -171,8 +171,7 @@ igt_simple_main
 		(long)intel_get_avail_ram_mb(),
 		(long)intel_get_total_ram_mb(),
 		(long)intel_get_total_swap_mb());
-
-	igt_require(count < intel_get_avail_ram_mb() + intel_get_total_swap_mb());
+	igt_require(intel_check_memory(count, 1024*1024, CHECK_RAM | CHECK_SWAP));
 
 	for (n = 0; n < count; n++) {
 		bo_handles[n] = create_bo_and_fill(fd);