@@ -34,8 +34,9 @@
#include <inttypes.h>
#include <pthread.h>
#include <errno.h>
-#include <sys/stat.h>
#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
#include "drm.h"
#include "igt.h"
@@ -323,6 +324,73 @@ test_pf_nonblock(int i915)
igt_spin_free(i915, spin);
}
+static void
+test_fork_bomb(int i915)
+{
+ uint32_t *control;
+ uint32_t handle;
+ int dmabuf;
+
+ /* Rebind the same object into many different process adress spaces. */
+
+ control = mmap(NULL, 4096, PROT_WRITE, MAP_SHARED | MAP_ANON, -1, 0);
+ igt_assert(control != MAP_FAILED);
+
+ handle = gem_create(i915, 4096);
+ dmabuf = prime_handle_to_fd(i915, handle);
+ gem_close(i915, handle);
+
+ igt_fork(child, 1) {
+ int fd[512];
+
+ atomic_fetch_add(&control[1], 1);
+ while (!READ_ONCE(control[0])) {
+ int children;
+
+ atomic_fetch_add(&control[2], 1);
+
+ for (int i = 0; i < ARRAY_SIZE(fd); i++) {
+ fd[i] = gem_reopen_driver(i915);
+
+ handle = prime_fd_to_handle(fd[i], dmabuf);
+ gem_mmap__gtt(fd[i], handle, 4096, PROT_WRITE);
+ gem_close(fd[i], handle);
+
+ /* leave the fd + mmap for process cleanup */
+ }
+
+ for (children = 0; children < 2; children++) {
+ if (fork() > 0) { /* child */
+ atomic_fetch_add(&control[1], 1);
+ for (int i = 0; i < ARRAY_SIZE(fd); i++)
+ close(fd[i]);
+ break;
+ }
+ }
+ if (children == 2) { /* parent */
+ sched_yield();
+ break;
+ }
+ }
+ atomic_fetch_add(&control[1], -1);
+ }
+
+ sleep(30);
+
+ *control = 1;
+ igt_waitchildren();
+
+ while (READ_ONCE(control[1])) {
+ int status = 0;
+ wait(&status);
+ }
+
+ igt_info("Spawned %d children\n", control[2]);
+
+ close(dmabuf);
+ munmap(control, 4096);
+}
+
static void
test_isolation(int i915)
{
@@ -1097,6 +1165,8 @@ igt_main
test_flink_race(fd);
igt_subtest("pf-nonblock")
test_pf_nonblock(fd);
+ igt_subtest("fork-bomb")
+ test_fork_bomb(fd);
igt_subtest("basic-small-bo")
test_huge_bo(fd, -1, I915_TILING_NONE);
Fork and remap the same object into a new process space under a new file descriptor. Principally to check list management and find scaling issues in using such lists. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Abdiel Janulgue <abdiel.janulgue@linux.intel.com> --- tests/i915/gem_mmap_gtt.c | 72 ++++++++++++++++++++++++++++++++++++++- 1 file changed, 71 insertions(+), 1 deletion(-)