From 3d81d589d6e3c89b687771074f65cb8f3b59ccf3 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Mon, 13 Feb 2017 17:15:31 +0000 Subject: [PATCH] drm/i915: Test exhaustion of the mmap space An unlikely error condition that we can simulate by stealing most of the range before trying to insert new objects. Signed-off-by: Chris Wilson Reviewed-by: Matthew Auld Link: http://patchwork.freedesktop.org/patch/msgid/20170213171558.20942-20-chris@chris-wilson.co.uk --- .../gpu/drm/i915/selftests/i915_gem_object.c | 138 ++++++++++++++++++ 1 file changed, 138 insertions(+) diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_object.c b/drivers/gpu/drm/i915/selftests/i915_gem_object.c index 99648f91194f..67d82bf1407f 100644 --- a/drivers/gpu/drm/i915/selftests/i915_gem_object.c +++ b/drivers/gpu/drm/i915/selftests/i915_gem_object.c @@ -25,6 +25,7 @@ #include "../i915_selftest.h" #include "mock_gem_device.h" +#include "huge_gem_object.h" static int igt_gem_object(void *arg) { @@ -432,6 +433,142 @@ out: return err; } +static int make_obj_busy(struct drm_i915_gem_object *obj) +{ + struct drm_i915_private *i915 = to_i915(obj->base.dev); + struct drm_i915_gem_request *rq; + struct i915_vma *vma; + int err; + + vma = i915_vma_instance(obj, &i915->ggtt.base, NULL); + if (IS_ERR(vma)) + return PTR_ERR(vma); + + err = i915_vma_pin(vma, 0, 0, PIN_USER); + if (err) + return err; + + rq = i915_gem_request_alloc(i915->engine[RCS], i915->kernel_context); + if (IS_ERR(rq)) { + i915_vma_unpin(vma); + return PTR_ERR(rq); + } + + i915_vma_move_to_active(vma, rq, 0); + i915_add_request(rq); + + i915_gem_object_set_active_reference(obj); + i915_vma_unpin(vma); + return 0; +} + +static bool assert_mmap_offset(struct drm_i915_private *i915, + unsigned long size, + int expected) +{ + struct drm_i915_gem_object *obj; + int err; + + obj = i915_gem_object_create_internal(i915, size); + if (IS_ERR(obj)) + return PTR_ERR(obj); + + err = i915_gem_object_create_mmap_offset(obj); + i915_gem_object_put(obj); + + return err == expected; +} + +static int igt_mmap_offset_exhaustion(void *arg) +{ + struct drm_i915_private *i915 = arg; + struct drm_mm *mm = &i915->drm.vma_offset_manager->vm_addr_space_mm; + struct drm_i915_gem_object *obj; + struct drm_mm_node resv, *hole; + u64 hole_start, hole_end; + int loop, err; + + /* Trim the device mmap space to only a page */ + memset(&resv, 0, sizeof(resv)); + drm_mm_for_each_hole(hole, mm, hole_start, hole_end) { + resv.start = hole_start; + resv.size = hole_end - hole_start - 1; /* PAGE_SIZE units */ + err = drm_mm_reserve_node(mm, &resv); + if (err) { + pr_err("Failed to trim VMA manager, err=%d\n", err); + return err; + } + break; + } + + /* Just fits! */ + if (!assert_mmap_offset(i915, PAGE_SIZE, 0)) { + pr_err("Unable to insert object into single page hole\n"); + err = -EINVAL; + goto out; + } + + /* Too large */ + if (!assert_mmap_offset(i915, 2*PAGE_SIZE, -ENOSPC)) { + pr_err("Unexpectedly succeeded in inserting too large object into single page hole\n"); + err = -EINVAL; + goto out; + } + + /* Fill the hole, further allocation attempts should then fail */ + obj = i915_gem_object_create_internal(i915, PAGE_SIZE); + if (IS_ERR(obj)) { + err = PTR_ERR(obj); + goto out; + } + + err = i915_gem_object_create_mmap_offset(obj); + if (err) { + pr_err("Unable to insert object into reclaimed hole\n"); + goto err_obj; + } + + if (!assert_mmap_offset(i915, PAGE_SIZE, -ENOSPC)) { + pr_err("Unexpectedly succeeded in inserting object into no holes!\n"); + err = -EINVAL; + goto err_obj; + } + + i915_gem_object_put(obj); + + /* Now fill with busy dead objects that we expect to reap */ + for (loop = 0; loop < 3; loop++) { + obj = i915_gem_object_create_internal(i915, PAGE_SIZE); + if (IS_ERR(obj)) { + err = PTR_ERR(obj); + goto out; + } + + mutex_lock(&i915->drm.struct_mutex); + err = make_obj_busy(obj); + mutex_unlock(&i915->drm.struct_mutex); + if (err) { + pr_err("[loop %d] Failed to busy the object\n", loop); + goto err_obj; + } + + GEM_BUG_ON(!i915_gem_object_is_active(obj)); + err = i915_gem_object_create_mmap_offset(obj); + if (err) { + pr_err("[loop %d] i915_gem_object_create_mmap_offset failed with err=%d\n", + loop, err); + goto out; + } + } + +out: + drm_mm_remove_node(&resv); + return err; +err_obj: + i915_gem_object_put(obj); + goto out; +} + int i915_gem_object_mock_selftests(void) { static const struct i915_subtest tests[] = { @@ -456,6 +593,7 @@ int i915_gem_object_live_selftests(struct drm_i915_private *i915) static const struct i915_subtest tests[] = { SUBTEST(igt_gem_huge), SUBTEST(igt_partial_tiling), + SUBTEST(igt_mmap_offset_exhaustion), }; return i915_subtests(tests, i915); -- 2.20.1