@@ -267,6 +267,21 @@ static void *no_contention(void *closure)
return NULL;
}
+static void *wc_mmap(void *closure)
+{
+ struct thread_contention *t = closure;
+ int n;
+
+ for (n = 0; n < t->loops; n++) {
+ uint32_t *ptr = gem_mmap__wc(t->fd, t->handle, 0, OBJECT_SIZE, PROT_READ | PROT_WRITE);
+ igt_assert(ptr);
+ memset(ptr + (rand() % 256) * 4096 / 4, 0, 4096);
+ munmap(ptr, OBJECT_SIZE);
+ }
+
+ return NULL;
+}
+
static void thread_contention(void)
{
const int loops = 4096;
@@ -322,6 +337,62 @@ static void thread_contention(void)
igt_assert(tiled[1] > 0.75 * tiled[0]);
}
+static void wc_contention(void)
+{
+ const int loops = 4096;
+ int n, count;
+ int fd, num_fences;
+ double linear[2], tiled[2];
+
+ fd = drm_open_any();
+ igt_require_mmap_wc(fd);
+
+ num_fences = gem_available_fences(fd);
+ igt_require(num_fences > 0);
+
+ for (count = 1; count < 4*num_fences; count *= 2) {
+ struct timeval start, end;
+ struct thread_contention threads[count];
+
+ for (n = 0; n < count; n++) {
+ threads[n].handle = gem_create(fd, OBJECT_SIZE);
+ threads[n].loops = loops;
+ threads[n].fd = fd;
+ }
+
+ gettimeofday(&start, NULL);
+ for (n = 0; n < count; n++)
+ pthread_create(&threads[n].thread, NULL, wc_mmap, &threads[n]);
+ for (n = 0; n < count; n++)
+ pthread_join(threads[n].thread, NULL);
+ gettimeofday(&end, NULL);
+
+ linear[count != 2] = count * loops / elapsed(&start, &end) / (OBJECT_SIZE / 4096);
+ igt_info("Contended upload rate for %d linear threads/wc: %7.3fMiB/s\n", count, linear[count != 2]);
+
+ for (n = 0; n < count; n++)
+ gem_set_tiling(fd, threads[n].handle, I915_TILING_X, 1024);
+
+ gettimeofday(&start, NULL);
+ for (n = 0; n < count; n++)
+ pthread_create(&threads[n].thread, NULL, wc_mmap, &threads[n]);
+ for (n = 0; n < count; n++)
+ pthread_join(threads[n].thread, NULL);
+ gettimeofday(&end, NULL);
+
+ tiled[count != 2] = count * loops / elapsed(&start, &end) / (OBJECT_SIZE / 4096);
+ igt_info("Contended upload rate for %d tiled threads/wc: %7.3fMiB/s\n", count, tiled[count != 2]);
+
+ for (n = 0; n < count; n++) {
+ gem_close(fd, threads[n].handle);
+ }
+ }
+
+ errno = 0;
+ igt_assert(linear[1] > 0.75 * linear[0]);
+ igt_assert(tiled[1] > 0.75 * tiled[0]);
+}
+
igt_main
{
igt_skip_on_simulation();
@@ -330,6 +401,8 @@ igt_main
performance();
igt_subtest("thread-contention")
thread_contention();
+ igt_subtest("wc-contention")
+ wc_contention();
igt_subtest("thread-performance-read")
thread_performance(READ);
igt_subtest("thread-performance-write")