[igt-dev] [PATCH i-g-t 5/9] i915/gem_userptr_blits: Apply some THP pressure

Chris Wilson
2019-08-13T06:20:12Z

Still trying to hit a deadlock with userptr from kcompatcd.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
tests/i915/gem_userptr_blits.c | 49 +++++++++++++++++++++++++++++-----
1 file changed, 42 insertions(+), 7 deletions(-)

diff --git a/tests/i915/gem_userptr_blits.c b/tests/i915/gem_userptr_blits.c
index 1373f160b..5f7770c93 100644
--- a/tests/i915/gem_userptr_blits.c
+++ b/tests/i915/gem_userptr_blits.c
@@ -1662,20 +1662,24 @@ struct stress_thread_data {
static void *mm_stress_thread(void *data)
{
struct stress_thread_data *stdata = (struct stress_thread_data *)data;
+ const size_t sz = 2 << 20;
void *ptr;
- int ret;

while (!stdata->stop) {
- ptr = mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE,
- MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+ ptr = mmap(NULL, sz, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
if (ptr == MAP_FAILED) {
stdata->exit_code = -EFAULT;
break;
}
- ret = munmap(ptr, PAGE_SIZE);
- if (ret) {
- stdata->exit_code = errno;
- break;
+
+ madvise(ptr, sz, MADV_HUGEPAGE);
+ for (size_t page = 0; page < sz; page += PAGE_SIZE)
+ *(volatile uint32_t *)((unsigned char *)ptr + page) = 0;
+
+ if (munmap(ptr, sz)) {
+ stdata->exit_code = errno;
+ break;
}
}

@@ -1713,6 +1717,35 @@ static void test_stress_mm(int fd)
igt_assert_eq(stdata.exit_code, 0);
}

+static void test_stress_purge(int fd)
+{
+ struct stress_thread_data stdata;
+ uint32_t handle;
+ pthread_t t;
+ void *ptr;
+
+ memset(&stdata, 0, sizeof(stdata));
+
+ igt_assert(posix_memalign(&ptr, PAGE_SIZE, PAGE_SIZE) == 0);
+ igt_assert(!pthread_create(&t, NULL, mm_stress_thread, &stdata));
+
+ igt_until_timeout(150) {
+ gem_userptr(fd, ptr, PAGE_SIZE, 0, userptr_flags, &handle);
+
+ gem_set_domain(fd, handle,
+ I915_GEM_DOMAIN_GTT, I915_GEM_DOMAIN_GTT);
+ intel_purge_vm_caches(fd);
+
+ gem_close(fd, handle);
+ }
+
+ free(ptr);
+
+ stdata.stop = 1;
+ igt_assert(!pthread_join(t, NULL));
+ igt_assert_eq(stdata.exit_code, 0);
+}
+
struct userptr_close_thread_data {
int fd;
void *ptr;
@@ -1975,6 +2008,8 @@ igt_main_args("c:", NULL, help_str, opt_handler, NULL)

igt_subtest("stress-mm")
test_stress_mm(fd);
+ igt_subtest("stress-purge")
+ test_stress_purge(fd);

igt_subtest("stress-mm-invalidate-close")
test_invalidate_close_race(fd, false);