On Tue, Sep 13, 2022 at 02:41:30PM +0800, shaoqin.huang@xxxxxxxxx wrote:
> From: Shaoqin Huang <shaoqin.huang@xxxxxxxxx>
>
> Add 129th region into the memblock, and this will trigger the
> memblock_double_array() function, this needs valid memory regions. So
> using dummy_physical_memory_init() to allocate a large enough memory
> region, and split it into a large enough memory which can be choosed by
> memblock_double_array(), and the left memory will be split into small
> memory region, and add them into the memblock. It make sure the
> memblock_double_array() will always choose the valid memory region that
> is allocated by the dummy_physical_memory_init().
> So memblock_double_array() must success.
>
> Another thing should be done is to restore the memory.regions after
> memblock_double_array(), due to now the memory.regions is pointing to a
> memory region allocated by dummy_physical_memory_init(). And it will
> affect the subsequent tests if we don't restore the memory region. So
> simply record the origin region, and restore it after the test.
>
> Signed-off-by: Shaoqin Huang <shaoqin.huang@xxxxxxxxx>
> ---
> tools/testing/memblock/tests/basic_api.c | 96 ++++++++++++++++++++++++
> tools/testing/memblock/tests/common.c | 7 +-
> tools/testing/memblock/tests/common.h | 3 +
> 3 files changed, 104 insertions(+), 2 deletions(-)
>
> diff --git a/tools/testing/memblock/tests/basic_api.c b/tools/testing/memblock/tests/basic_api.c
> index a13a57ba0815..7120fd8e47b1 100644
> --- a/tools/testing/memblock/tests/basic_api.c
> +++ b/tools/testing/memblock/tests/basic_api.c
> @@ -423,6 +423,101 @@ static int memblock_add_near_max_check(void)
> return 0;
> }
>
> +/*
> + * A test that trying to add the 129th memory block.
> + * Expect to trigger memblock_double_array() to double the
> + * memblock.memory.max, find a new valid memory as
> + * memory.regions.
> + */
> +static int memblock_add_many_check(void)
> +{
> + int i;
> + void *orig_region;
> + struct region r = {
> + .base = SZ_16K,
> + .size = MEM_SIZE,
> + };
> + phys_addr_t new_memory_regions_size;
> + phys_addr_t base, size, block_size;
> +
> + PREFIX_PUSH();
> +
> + reset_memblock_regions();
> + memblock_allow_resize();
> +
> + dummy_physical_memory_init();
> + /*
> + * We allocated enough memory by using dummy_physical_memory_init(), and
> + * split it into small block. First we split a large enough memory block
> + * as the memory region which will be choosed by memblock_double_array().
> + */
> + base = PAGE_ALIGN(dummy_physical_memory_base());
> + new_memory_regions_size = PAGE_ALIGN(INIT_MEMBLOCK_REGIONS * 2 *
> + sizeof(struct memblock_region));
> + memblock_add(base, new_memory_regions_size);
Why don't you simply increase MEM_SIZE, to say 1M?
This will make all the calculations here way simpler.
> +
> + /*
> + * For the left memory, we split them into small block and add them into
> + * memblock later.
> + */
> + base += new_memory_regions_size;
> + size = MEM_SIZE - new_memory_regions_size;
> + block_size = size / (INIT_MEMBLOCK_REGIONS * 2);
> +
> + orig_region = memblock.memory.regions;
> +
> + for (i = 0; i < INIT_MEMBLOCK_REGIONS; i++) {
> + /*
> + * Add these small block to fulfill the memblock. We keep an
> + * interval between the nearby memory to avoid being merged.
> + */
> + memblock_add(base + block_size * (2 * i + 1), block_size);
> +
> + ASSERT_EQ(memblock.memory.cnt, i + 2);
> + ASSERT_EQ(memblock.memory.total_size, new_memory_regions_size +
> + (i + 1) * block_size);
> + }
> +
> + /*
> + * At there, memblock_double_array() has been succeed, check if it
> + * update the memory.max.
> + */
> + ASSERT_EQ(memblock.memory.max, INIT_MEMBLOCK_REGIONS * 2);
> +
> + /* memblock_double_array() will reserve the memory it used. Check it. */
> + ASSERT_EQ(memblock.reserved.cnt, 1);
> + ASSERT_EQ(memblock.reserved.total_size, new_memory_regions_size);
> +
> + /*
> + * Now memblock_double_array() works fine. Let's check after the
> + * double_array(), the memblock_add() still works as normal.
> + */
> + memblock_add(r.base, r.size);
> + ASSERT_EQ(memblock.memory.regions[0].base, r.base);
> + ASSERT_EQ(memblock.memory.regions[0].size, r.size);
> +
> + ASSERT_EQ(memblock.memory.cnt, INIT_MEMBLOCK_REGIONS + 2);
> + ASSERT_EQ(memblock.memory.total_size, INIT_MEMBLOCK_REGIONS * block_size +
> + new_memory_regions_size +
> + MEM_SIZE);
> + ASSERT_EQ(memblock.memory.max, INIT_MEMBLOCK_REGIONS * 2);
> +
> + dummy_physical_memory_cleanup();
> +
> + /*
> + * The current memory.regions is occupying a range of memory that
> + * allocated from dummy_physical_memory_init(). After free the memory,
> + * we must not use it. So restore the origin memory region to make sure
> + * the tests can run as normal and not affected by the double array.
> + */
> + memblock.memory.regions = orig_region;
> + memblock.memory.cnt = INIT_MEMBLOCK_REGIONS;
> +
> + test_pass_pop();
> +
> + return 0;
> +}
> +
> static int memblock_add_checks(void)
> {
> prefix_reset();
> @@ -438,6 +533,7 @@ static int memblock_add_checks(void)
> memblock_add_twice_check();
> memblock_add_between_check();
> memblock_add_near_max_check();
> + memblock_add_many_check();
>
> prefix_pop();
>
> diff --git a/tools/testing/memblock/tests/common.c b/tools/testing/memblock/tests/common.c
> index eec6901081af..2de6a2b6efd2 100644
> --- a/tools/testing/memblock/tests/common.c
> +++ b/tools/testing/memblock/tests/common.c
> @@ -5,8 +5,6 @@
> #include <linux/memory_hotplug.h>
> #include <linux/build_bug.h>
>
> -#define INIT_MEMBLOCK_REGIONS 128
> -#define INIT_MEMBLOCK_RESERVED_REGIONS INIT_MEMBLOCK_REGIONS
> #define PREFIXES_MAX 15
> #define DELIM ": "
>
> @@ -84,6 +82,11 @@ void dummy_physical_memory_cleanup(void)
> free(memory_block.base);
> }
>
> +phys_addr_t dummy_physical_memory_base(void)
> +{
> + return (phys_addr_t)memory_block.base;
> +}
> +
> static void usage(const char *prog)
> {
> BUILD_BUG_ON(ARRAY_SIZE(help_opts) != ARRAY_SIZE(long_opts) - 1);
> diff --git a/tools/testing/memblock/tests/common.h b/tools/testing/memblock/tests/common.h
> index 78128e109a95..ba14dc989ae9 100644
> --- a/tools/testing/memblock/tests/common.h
> +++ b/tools/testing/memblock/tests/common.h
> @@ -11,6 +11,8 @@
> #include <../selftests/kselftest.h>
>
> #define MEM_SIZE SZ_16K
> +#define INIT_MEMBLOCK_REGIONS 128
> +#define INIT_MEMBLOCK_RESERVED_REGIONS INIT_MEMBLOCK_REGIONS
>
> enum test_flags {
> /* No special request. */
> @@ -104,6 +106,7 @@ void reset_memblock_attributes(void);
> void setup_memblock(void);
> void dummy_physical_memory_init(void);
> void dummy_physical_memory_cleanup(void);
> +phys_addr_t dummy_physical_memory_base(void);
> void parse_args(int argc, char **argv);
>
> void test_fail(void);
> --
> 2.34.1
>
>
--
Sincerely yours,
Mike.
