RE: [PATCH 5.15.y 1/2] mm/damon/vaddr-test: split a test function having >1024 bytes frame size

From: SeongJae Park

Sent: 06 December 2024 18:16

On some configuration[1], 'damon_test_split_evenly()' kunit test function has >1024 bytes frame size, so below build warning is triggered:

  CC      mm/damon/vaddr.o
In file included from mm/damon/vaddr.c:672:
mm/damon/vaddr-test.h: In function 'damon_test_split_evenly':
mm/damon/vaddr-test.h:309:1: warning: the frame size of 1064 bytes is larger than 1024 bytes [-

Wframe-larger-than=] 309 | } | ^

This commit fixes the warning by separating the common logic in the function.

In that guaranteed to make any difference without some noinline_for_stack attributes?

Not that I can see exactly where the stack was used. But it tends to be clang that doesn't re-use stack space.

David

[1] https://lore.kernel.org/linux-mm/202111182146.OV3C4uGr-lkp@intel.com/

Link: https://lkml.kernel.org/r/20211201150440.1088-6-sj@kernel.org Fixes: 17ccae8bb5c9 ("mm/damon: add kunit tests") Signed-off-by: SeongJae Park sj@kernel.org Reported-by: kernel test robot lkp@intel.com Cc: Brendan Higgins brendanhiggins@google.com Cc: Shuah Khan shuah@kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org (cherry picked from commit 044cd9750fe010170f5dc812e4824d98f5ea928c)

---

mm/damon/vaddr-test.h | 77 ++++++++++++++++++++++--------------------- 1 file changed, 40 insertions(+), 37 deletions(-)

diff --git a/mm/damon/vaddr-test.h b/mm/damon/vaddr-test.h index 1f5c13257dba..95ec362cdc37 100644 --- a/mm/damon/vaddr-test.h +++ b/mm/damon/vaddr-test.h @@ -252,59 +252,62 @@ static void damon_test_apply_three_regions4(struct kunit *test) new_three_regions, expected, ARRAY_SIZE(expected)); }

-static void damon_test_split_evenly(struct kunit *test) +static void damon_test_split_evenly_fail(struct kunit *test,

• unsigned long start, unsigned long end, unsigned int nr_pieces)
  

{

• struct damon_ctx *c = damon_new_ctx();
• struct damon_target *t;
• struct damon_region *r;
• unsigned long i;
• KUNIT_EXPECT_EQ(test, damon_va_evenly_split_region(NULL, NULL, 5),

• 	-EINVAL);
  

• t = damon_new_target(42);
• r = damon_new_region(0, 100);
• KUNIT_EXPECT_EQ(test, damon_va_evenly_split_region(t, r, 0), -EINVAL);

• struct damon_target *t = damon_new_target(42);

• struct damon_region *r = damon_new_region(start, end);

  damon_add_region(r, t);

• KUNIT_EXPECT_EQ(test, damon_va_evenly_split_region(t, r, 10), 0);
• KUNIT_EXPECT_EQ(test, damon_nr_regions(t), 10u);

• KUNIT_EXPECT_EQ(test,

• 	damon_va_evenly_split_region(t, r, nr_pieces), -EINVAL);
  

• KUNIT_EXPECT_EQ(test, damon_nr_regions(t), 1u);

• i = 0; damon_for_each_region(r, t) {

• KUNIT_EXPECT_EQ(test, r->ar.start, i++ * 10);
  

• KUNIT_EXPECT_EQ(test, r->ar.end, i * 10);
  

• KUNIT_EXPECT_EQ(test, r->ar.start, start);
  

• KUNIT_EXPECT_EQ(test, r->ar.end, end);
  

  }
• damon_free_target(t);

+}

+static void damon_test_split_evenly_succ(struct kunit *test,

• unsigned long start, unsigned long end, unsigned int nr_pieces)

+{

• struct damon_target *t = damon_new_target(42);
• struct damon_region *r = damon_new_region(start, end);
• unsigned long expected_width = (end - start) / nr_pieces;
• unsigned long i = 0;

• t = damon_new_target(42);
• r = damon_new_region(5, 59); damon_add_region(r, t);
• KUNIT_EXPECT_EQ(test, damon_va_evenly_split_region(t, r, 5), 0);
• KUNIT_EXPECT_EQ(test, damon_nr_regions(t), 5u);

• KUNIT_EXPECT_EQ(test,

• 	damon_va_evenly_split_region(t, r, nr_pieces), 0);
  

• KUNIT_EXPECT_EQ(test, damon_nr_regions(t), nr_pieces);

• i = 0; damon_for_each_region(r, t) {

• if (i == 4)
  

• if (i == nr_pieces - 1)
  break;
  

• KUNIT_EXPECT_EQ(test, r->ar.start, 5 + 10 * i++);
  

• KUNIT_EXPECT_EQ(test, r->ar.end, 5 + 10 * i);
  

• KUNIT_EXPECT_EQ(test,
  

• 		r->ar.start, start + i++ * expected_width);
  

• KUNIT_EXPECT_EQ(test, r->ar.end, start + i * expected_width);
  

  }

• KUNIT_EXPECT_EQ(test, r->ar.start, 5 + 10 * i);
• KUNIT_EXPECT_EQ(test, r->ar.end, 59ul);

• KUNIT_EXPECT_EQ(test, r->ar.start, start + i * expected_width);
• KUNIT_EXPECT_EQ(test, r->ar.end, end); damon_free_target(t);

+}

• t = damon_new_target(42);
• r = damon_new_region(5, 6);
• damon_add_region(r, t);
• KUNIT_EXPECT_EQ(test, damon_va_evenly_split_region(t, r, 2), -EINVAL);
• KUNIT_EXPECT_EQ(test, damon_nr_regions(t), 1u);

+static void damon_test_split_evenly(struct kunit *test) +{

• struct damon_ctx *c = damon_new_ctx();
• KUNIT_EXPECT_EQ(test, damon_va_evenly_split_region(NULL, NULL, 5),

• 	-EINVAL);
  

• damon_test_split_evenly_fail(test, 0, 100, 0);
• damon_test_split_evenly_succ(test, 0, 100, 10);
• damon_test_split_evenly_succ(test, 5, 59, 5);
• damon_test_split_evenly_fail(test, 5, 6, 2);

• damon_for_each_region(r, t) {

• KUNIT_EXPECT_EQ(test, r->ar.start, 5ul);
  

• KUNIT_EXPECT_EQ(test, r->ar.end, 6ul);
  

• }
• damon_free_target(t); damon_destroy_ctx(c);

}

-- 2.39.5

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