Re: [PATCH v5] resource: add a simple test for walk_iomem_res_desc()

[Chia-I Wu]

On Wed, Jun 5, 2024 at 5:40 PM Chia-I Wu <olvaffe@xxxxxxxxx> wrote:
>
> This mainly tests that find_next_iomem_res() does not miss resources.
>
> Signed-off-by: Chia-I Wu <olvaffe@xxxxxxxxx>
>
> ---
> v2: update subject, use DEFINE_RES_NAMED and hardcoded offsets
> v3: really hardcode offsets, with 4KB intervals since 0x1000 is easier
>     to read than 0x400
> v4: use RESOURCE_SIZE_MAX, split allocate_resource and KUNIT_ASSERT_EQ,
>     and other cosmetic changes
> v5: include linux/limits.h, add a comment on the resource layout, and
>     add more negative tests for holes
> ---
>  kernel/resource_kunit.c | 99 +++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 99 insertions(+)
>
> diff --git a/kernel/resource_kunit.c b/kernel/resource_kunit.c
> index 58ab9f914602b..b13f01f290606 100644
> --- a/kernel/resource_kunit.c
> +++ b/kernel/resource_kunit.c
> @@ -6,6 +6,7 @@
>  #include <kunit/test.h>
>  #include <linux/ioport.h>
>  #include <linux/kernel.h>
> +#include <linux/limits.h>
>  #include <linux/string.h>
>
>  #define R0_START       0x0000
> @@ -137,9 +138,107 @@ static void resource_test_intersection(struct kunit *test)
>         } while (++i < ARRAY_SIZE(results_for_intersection));
>  }
>
> +static int resource_walk_count(struct resource *res, void *data)
> +{
> +       int *count = data;
> +
> +       (*count)++;
> +       return 0;
> +}
> +
> +static void resource_test_walk_iomem_res_desc(struct kunit *test)
> +{
> +       struct resource root = {
> +               .name = "Resource Walk Test",
> +       };
> +       struct resource res[8];
> +       int count;
> +       int ret;
> +
> +       ret = allocate_resource(&iomem_resource, &root, 0x100000,
> +                       0, RESOURCE_SIZE_MAX, 0x100000, NULL, NULL);
> +       KUNIT_ASSERT_EQ(test, 0, ret);
> +
> +       /* build the resource tree under the test root:
> +        *
> +        *   0x0000-0x0fff: res[0], a match
> +        *   0x1000-0x1fff: res[1], a non-match
> +        *   0x2000-0x2fff: a hole
> +        *   0x3000-0x3fff: res[2], a non-match
> +        *     0x3800-0x3bff: res[3], a match
> +        *   0x4000-0x4fff: res[4], a match
> +        */
> +       res[0] = DEFINE_RES_NAMED(root.start + 0x0000, 0x1000, "SYSRAM 1",
> +                       IORESOURCE_SYSTEM_RAM);
> +       res[1] = DEFINE_RES_NAMED(root.start + 0x1000, 0x1000, "OTHER", 0);
> +
> +       res[2] = DEFINE_RES_NAMED(root.start + 0x3000, 0x1000, "NESTED", 0);
> +       res[3] = DEFINE_RES_NAMED(root.start + 0x3800, 0x0400, "SYSRAM 2",
> +                       IORESOURCE_SYSTEM_RAM);
> +
> +       res[4] = DEFINE_RES_NAMED(root.start + 0x4000, 0x1000, "SYSRAM 3",
> +                       IORESOURCE_SYSTEM_RAM);
> +
> +       KUNIT_EXPECT_EQ(test, 0, request_resource(&root, &res[0]));
> +       KUNIT_EXPECT_EQ(test, 0, request_resource(&root, &res[1]));
> +       KUNIT_EXPECT_EQ(test, 0, request_resource(&root, &res[2]));
> +       KUNIT_EXPECT_EQ(test, 0, request_resource(&res[2], &res[3]));
> +       KUNIT_EXPECT_EQ(test, 0, request_resource(&root, &res[4]));
> +
> +       /* walk the entire region */
> +       count = 0;
> +       walk_iomem_res_desc(IORES_DESC_NONE, IORESOURCE_SYSTEM_RAM,
> +                       root.start, root.end, &count, resource_walk_count);
> +       KUNIT_EXPECT_EQ(test, count, 3);
> +
> +       /* walk the region requested by res[0] */
> +       count = 0;
> +       walk_iomem_res_desc(IORES_DESC_NONE, IORESOURCE_SYSTEM_RAM,
> +                       res[0].start, res[0].end, &count, resource_walk_count);
> +       KUNIT_EXPECT_EQ(test, count, 1);
> +
> +       /* walk the region requested by res[1] */
> +       count = 0;
> +       walk_iomem_res_desc(IORES_DESC_NONE, IORESOURCE_SYSTEM_RAM,
> +                       res[1].start, res[1].end, &count, resource_walk_count);
> +       KUNIT_EXPECT_EQ(test, count, 0);
> +
> +       /* walk the hole between res[1] and res[2] */
> +       count = 0;
> +       walk_iomem_res_desc(IORES_DESC_NONE, IORESOURCE_SYSTEM_RAM,
> +                       res[1].end + 1, res[2].start - 1, &count,
> +                       resource_walk_count);
> +       KUNIT_EXPECT_EQ(test, count, 0);
> +
> +       /* walk the region requested by res[2] */
> +       count = 0;
> +       walk_iomem_res_desc(IORES_DESC_NONE, IORESOURCE_SYSTEM_RAM,
> +                       res[2].start, res[2].end, &count, resource_walk_count);
> +       KUNIT_EXPECT_EQ(test, count, 1);
> +
> +       /* walk the holes before and after res[3] nested under res[2] */
> +       count = 0;
> +       walk_iomem_res_desc(IORES_DESC_NONE, IORESOURCE_SYSTEM_RAM,
> +                       res[2].start, res[3].start - 1, &count,
> +                       resource_walk_count);
> +       walk_iomem_res_desc(IORES_DESC_NONE, IORESOURCE_SYSTEM_RAM,
> +                       res[2].end + 1, res[3].end, &count,
This should be from "res[3].end + 1" to "res[2].end".  Not sure if I
should resend or if you can make the fix when applying.

> +                       resource_walk_count);
> +       KUNIT_EXPECT_EQ(test, count, 0);
> +
> +       /* walk the region requested by res[4] */
> +       count = 0;
> +       walk_iomem_res_desc(IORES_DESC_NONE, IORESOURCE_SYSTEM_RAM,
> +                       res[4].start, res[4].end, &count, resource_walk_count);
> +       KUNIT_EXPECT_EQ(test, count, 1);
> +
> +       release_resource(&root);
> +}
> +
>  static struct kunit_case resource_test_cases[] = {
>         KUNIT_CASE(resource_test_union),
>         KUNIT_CASE(resource_test_intersection),
> +       KUNIT_CASE(resource_test_walk_iomem_res_desc),
>         {}
>  };
>
> --
> 2.45.1.467.gbab1589fc0-goog
>