From a324b4be219a0f34cd4e5730557adb7c5c61b176 Mon Sep 17 00:00:00 2001
From: Matthew Auld <matthew.auld@intel.com>
Date: Mon, 6 Sep 2021 10:17:29 +0100
Subject: drm/i915/selftests: fixup igt_shrink_thp
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Git-commit: f503eb0cf2badfd8a70dac5d2a48a3e83550278e
Patch-mainline: v5.16-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225

Since the object might still be active here, the shrink_all will simply
ignore it, which blows up in the test, since the pages will still be
there. Currently THP is disabled which should result in the test being
skipped, but if we ever re-enable THP we might start seeing the failure.
Fix this by forcing I915_SHRINK_ACTIVE.

v2: Some machine in the shard runs doesn't seem to have any available
swap when running this test. Try to handle this.

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210906091729.2093312-1-matthew.auld@intel.com
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 .../gpu/drm/i915/gem/selftests/huge_pages.c   | 30 ++++++++++++++-----
 1 file changed, 23 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/selftests/huge_pages.c b/drivers/gpu/drm/i915/gem/selftests/huge_pages.c
index 5d71626a1ee5..0827634c842c 100644
--- a/drivers/gpu/drm/i915/gem/selftests/huge_pages.c
+++ b/drivers/gpu/drm/i915/gem/selftests/huge_pages.c
@@ -1519,6 +1519,7 @@ static int igt_shrink_thp(void *arg)
 	struct i915_vma *vma;
 	unsigned int flags = PIN_USER;
 	unsigned int n;
+	bool should_swap;
 	int err = 0;
 
 	/*
@@ -1567,23 +1568,38 @@ static int igt_shrink_thp(void *arg)
 			break;
 	}
 	i915_gem_context_unlock_engines(ctx);
+	/*
+	 * Nuke everything *before* we unpin the pages so we can be reasonably
+	 * sure that when later checking get_nr_swap_pages() that some random
+	 * leftover object doesn't steal the remaining swap space.
+	 */
+	i915_gem_shrink(NULL, i915, -1UL, NULL,
+			I915_SHRINK_BOUND |
+			I915_SHRINK_UNBOUND |
+			I915_SHRINK_ACTIVE);
 	i915_vma_unpin(vma);
 	if (err)
 		goto out_put;
 
 	/*
-	 * Now that the pages are *unpinned* shrink-all should invoke
-	 * shmem to truncate our pages.
+	 * Now that the pages are *unpinned* shrinking should invoke
+	 * shmem to truncate our pages, if we have available swap.
 	 */
-	i915_gem_shrink_all(i915);
-	if (i915_gem_object_has_pages(obj)) {
-		pr_err("shrink-all didn't truncate the pages\n");
+	should_swap = get_nr_swap_pages() > 0;
+	i915_gem_shrink(NULL, i915, -1UL, NULL,
+			I915_SHRINK_BOUND |
+			I915_SHRINK_UNBOUND |
+			I915_SHRINK_ACTIVE);
+	if (should_swap == i915_gem_object_has_pages(obj)) {
+		pr_err("unexpected pages mismatch, should_swap=%s\n",
+		       yesno(should_swap));
 		err = -EINVAL;
 		goto out_put;
 	}
 
-	if (obj->mm.page_sizes.sg || obj->mm.page_sizes.phys) {
-		pr_err("residual page-size bits left\n");
+	if (should_swap == (obj->mm.page_sizes.sg || obj->mm.page_sizes.phys)) {
+		pr_err("unexpected residual page-size bits, should_swap=%s\n",
+		       yesno(should_swap));
 		err = -EINVAL;
 		goto out_put;
 	}
-- 
2.38.1