igt/gem_exec_nop: Repeat and average to stabilize measurements
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/tests/gem_exec_nop.c b/tests/gem_exec_nop.c
index f110c9d..235c8f6 100644
--- a/tests/gem_exec_nop.c
+++ b/tests/gem_exec_nop.c
@@ -41,8 +41,22 @@
#include "drmtest.h"
#include "intel_io.h"
+#define LOCAL_I915_EXEC_NO_RELOC (1<<11)
+#define LOCAL_I915_EXEC_HANDLE_LUT (1<<12)
+
#define LOCAL_I915_EXEC_VEBOX (4<<0)
+static int dcmp(const void *A, const void *B)
+{
+ double a = *(double *)A, b = *(double *)B;
+ if (a < b)
+ return -1;
+ else if (a > b)
+ return 1;
+ else
+ return 0;
+}
+
static double elapsed(const struct timeval *start,
const struct timeval *end,
int loop)
@@ -50,56 +64,53 @@
return (1e6*(end->tv_sec - start->tv_sec) + (end->tv_usec - start->tv_usec))/loop;
}
-static int exec(int fd, uint32_t handle, int loops, unsigned ring_id)
+static void loop(int fd, uint32_t handle, unsigned ring_id, const char *ring_name)
{
struct drm_i915_gem_execbuffer2 execbuf;
struct drm_i915_gem_exec_object2 gem_exec[1];
- int ret = 0;
-
- gem_exec[0].handle = handle;
- gem_exec[0].relocation_count = 0;
- gem_exec[0].relocs_ptr = 0;
- gem_exec[0].alignment = 0;
- gem_exec[0].offset = 0;
- gem_exec[0].flags = 0;
- gem_exec[0].rsvd1 = 0;
- gem_exec[0].rsvd2 = 0;
-
- execbuf.buffers_ptr = (uintptr_t)gem_exec;
- execbuf.buffer_count = 1;
- execbuf.batch_start_offset = 0;
- execbuf.batch_len = 8;
- execbuf.cliprects_ptr = 0;
- execbuf.num_cliprects = 0;
- execbuf.DR1 = 0;
- execbuf.DR4 = 0;
- execbuf.flags = ring_id;
- i915_execbuffer2_set_context_id(execbuf, 0);
- execbuf.rsvd2 = 0;
-
- while (loops-- && ret == 0) {
- if (drmIoctl(fd, DRM_IOCTL_I915_GEM_EXECBUFFER2, &execbuf))
- ret = -errno;
- }
- gem_sync(fd, handle);
-
- return ret;
-}
-
-static void loop(int fd, uint32_t handle, unsigned ring_id, const char *ring_name)
-{
int count;
gem_require_ring(fd, ring_id);
- for (count = 1; count <= SLOW_QUICK(1<<17, 1<<4); count <<= 1) {
- struct timeval start, end;
+ memset(&gem_exec, 0, sizeof(gem_exec));
+ gem_exec[0].handle = handle;
- gettimeofday(&start, NULL);
- igt_assert_eq(exec(fd, handle, count, ring_id), 0);
- gettimeofday(&end, NULL);
+ memset(&execbuf, 0, sizeof(execbuf));
+ execbuf.buffers_ptr = (uintptr_t)gem_exec;
+ execbuf.buffer_count = 1;
+ execbuf.flags = ring_id;
+ execbuf.flags |= LOCAL_I915_EXEC_HANDLE_LUT;
+ execbuf.flags |= LOCAL_I915_EXEC_NO_RELOC;
+ if (drmIoctl(fd, DRM_IOCTL_I915_GEM_EXECBUFFER2, &execbuf)) {
+ execbuf.flags = ring_id;
+ do_ioctl(fd, DRM_IOCTL_I915_GEM_EXECBUFFER2, &execbuf);
+ }
+ gem_sync(fd, handle);
+
+ for (count = 1; count <= SLOW_QUICK(1<<17, 1<<4); count <<= 1) {
+ const int reps = 9;
+ double t[reps], sum;
+ int n;
+
+ for (n = 0; n < reps; n++) {
+ struct timeval start, end;
+ int loops = count;
+ gettimeofday(&start, NULL);
+ while (loops--)
+ do_ioctl(fd, DRM_IOCTL_I915_GEM_EXECBUFFER2, &execbuf);
+ gem_sync(fd, handle);
+ gettimeofday(&end, NULL);
+ t[n] = elapsed(&start, &end, count);
+ }
+
+ qsort(t, reps, sizeof(double), dcmp);
+ sum = 0;
+ for (n = 2; n < reps-2; n++)
+ sum += t[n];
+ sum /= reps - 4;
+
igt_info("Time to exec x %d: %7.3fµs (ring=%s)\n",
- count, elapsed(&start, &end, count), ring_name);
+ count, sum, ring_name);
fflush(stdout);
}
}