2022-08-28 18:38:35

by Maira Canal

[permalink] [raw]
Subject: [PATCH] drm/mm: Reduce stack frame usage in __igt_reserve

The struct drm_mm is being allocated on the stack, which is causing the
following -Wframe-larger-than warning on ARM:

../drivers/gpu/drm/tests/drm_mm_test.c:344:12: error: stack frame size
(1064) exceeds limit (1024) in '__igt_reserve' [-Werror,-Wframe-larger-than]

static int __igt_reserve(struct kunit *test, unsigned int count, u64 size)
^
1 error generated.

So, fix this warning by dynamically allocating the struct drm_mm.

Fixes: fc8d29e298cf ("drm: selftest: convert drm_mm selftest to KUnit")
Reported-by: kernel test robot <[email protected]>
Signed-off-by: MaĆ­ra Canal <[email protected]>
---
drivers/gpu/drm/tests/drm_mm_test.c | 33 ++++++++++++++++-------------
1 file changed, 18 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/tests/drm_mm_test.c b/drivers/gpu/drm/tests/drm_mm_test.c
index 1e2c1aa524bd..fbd8dcbc12ee 100644
--- a/drivers/gpu/drm/tests/drm_mm_test.c
+++ b/drivers/gpu/drm/tests/drm_mm_test.c
@@ -344,7 +344,7 @@ static bool check_reserve_boundaries(struct kunit *test, struct drm_mm *mm,
static int __igt_reserve(struct kunit *test, unsigned int count, u64 size)
{
DRM_RND_STATE(prng, random_seed);
- struct drm_mm mm;
+ struct drm_mm *mm;
struct drm_mm_node tmp, *nodes, *node, *next;
unsigned int *order, n, m, o = 0;
int ret, err;
@@ -366,17 +366,20 @@ static int __igt_reserve(struct kunit *test, unsigned int count, u64 size)
nodes = vzalloc(array_size(count, sizeof(*nodes)));
KUNIT_ASSERT_TRUE(test, nodes);

+ mm = kunit_kzalloc(test, sizeof(struct drm_mm), GFP_KERNEL);
+ KUNIT_ASSERT_NOT_NULL(test, mm);
+
ret = -EINVAL;
- drm_mm_init(&mm, 0, count * size);
+ drm_mm_init(mm, 0, count * size);

- if (!check_reserve_boundaries(test, &mm, count, size))
+ if (!check_reserve_boundaries(test, mm, count, size))
goto out;

for (n = 0; n < count; n++) {
nodes[n].start = order[n] * size;
nodes[n].size = size;

- err = drm_mm_reserve_node(&mm, &nodes[n]);
+ err = drm_mm_reserve_node(mm, &nodes[n]);
if (err) {
KUNIT_FAIL(test, "reserve failed, step %d, start %llu\n",
n, nodes[n].start);
@@ -390,23 +393,23 @@ static int __igt_reserve(struct kunit *test, unsigned int count, u64 size)
goto out;
}

- if (!expect_reserve_fail(test, &mm, &nodes[n]))
+ if (!expect_reserve_fail(test, mm, &nodes[n]))
goto out;
}

/* After random insertion the nodes should be in order */
- if (!assert_continuous(test, &mm, size))
+ if (!assert_continuous(test, mm, size))
goto out;

/* Repeated use should then fail */
drm_random_reorder(order, count, &prng);
for (n = 0; n < count; n++) {
- if (!expect_reserve_fail(test, &mm, set_node(&tmp, order[n] * size, 1)))
+ if (!expect_reserve_fail(test, mm, set_node(&tmp, order[n] * size, 1)))
goto out;

/* Remove and reinsert should work */
drm_mm_remove_node(&nodes[order[n]]);
- err = drm_mm_reserve_node(&mm, &nodes[order[n]]);
+ err = drm_mm_reserve_node(mm, &nodes[order[n]]);
if (err) {
KUNIT_FAIL(test, "reserve failed, step %d, start %llu\n",
n, nodes[n].start);
@@ -415,16 +418,16 @@ static int __igt_reserve(struct kunit *test, unsigned int count, u64 size)
}
}

- if (!assert_continuous(test, &mm, size))
+ if (!assert_continuous(test, mm, size))
goto out;

/* Overlapping use should then fail */
for (n = 0; n < count; n++) {
- if (!expect_reserve_fail(test, &mm, set_node(&tmp, 0, size * count)))
+ if (!expect_reserve_fail(test, mm, set_node(&tmp, 0, size * count)))
goto out;
}
for (n = 0; n < count; n++) {
- if (!expect_reserve_fail(test, &mm, set_node(&tmp, size * n, size * (count - n))))
+ if (!expect_reserve_fail(test, mm, set_node(&tmp, size * n, size * (count - n))))
goto out;
}

@@ -437,7 +440,7 @@ static int __igt_reserve(struct kunit *test, unsigned int count, u64 size)

for (m = 0; m < n; m++) {
node = &nodes[order[(o + m) % count]];
- err = drm_mm_reserve_node(&mm, node);
+ err = drm_mm_reserve_node(mm, node);
if (err) {
KUNIT_FAIL(test, "reserve failed, step %d/%d, start %llu\n",
m, n, node->start);
@@ -448,15 +451,15 @@ static int __igt_reserve(struct kunit *test, unsigned int count, u64 size)

o += n;

- if (!assert_continuous(test, &mm, size))
+ if (!assert_continuous(test, mm, size))
goto out;
}

ret = 0;
out:
- drm_mm_for_each_node_safe(node, next, &mm)
+ drm_mm_for_each_node_safe(node, next, mm)
drm_mm_remove_node(node);
- drm_mm_takedown(&mm);
+ drm_mm_takedown(mm);
vfree(nodes);
kfree(order);
err:
--
2.37.2