On 9/1/2022 4:08 PM, Mike Rapoport wrote:
On Tue, Aug 30, 2022 at 09:49:18AM +0800, shaoqin.huang@xxxxxxxxx wrote:
From: Shaoqin Huang <shaoqin.huang@xxxxxxxxx>
Reserve 129th region in 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 valid memory region.
At the same time, reserve 128 faked memory region, and make sure these
reserved region not intersect with the valid memory region. So
memblock_double_array() will choose the valid memory region, and it will
success.
Also need to restore the reserved.regions after memblock_double_array(),
to make sure the subsequent tests can run as normal.
Signed-off-by: Shaoqin Huang <shaoqin.huang@xxxxxxxxx>
---
tools/testing/memblock/tests/basic_api.c | 87 ++++++++++++++++++++++++
1 file changed, 87 insertions(+)
diff --git a/tools/testing/memblock/tests/basic_api.c b/tools/testing/memblock/tests/basic_api.c
index c8e201156cdc..d8defc9866cb 100644
--- a/tools/testing/memblock/tests/basic_api.c
+++ b/tools/testing/memblock/tests/basic_api.c
@@ -686,6 +686,92 @@ static int memblock_reserve_twice_check(void)
return 0;
}
+/*
+ * A test that tries to reserve the 129th memory block.
+ * Expect to trigger memblock_double_array() to double the
+ * memblock.memory.max, find a new valid memory as
+ * reserved.regions.
+ */
+static int memblock_reserve_many_check(void)
+{
+ int i;
+ void *orig_region;
+ struct region r = {
+ .base = SZ_16K,
+ .size = MEM_SIZE,
+ };
+ phys_addr_t memory_base = SZ_128K;
+ phys_addr_t new_reserved_regions_size;
+
+ PREFIX_PUSH();
+
+ reset_memblock_regions();
+ memblock_allow_resize();
+
+ /* Add a valid memory region used by double_array(). */
+ dummy_physical_memory_init();
+ memblock_add((phys_addr_t)get_memory_block_base(), MEM_SIZE);
+
+ for (i = 0; i < INIT_MEMBLOCK_REGIONS; i++) {
+ /* Reserve some fakes memory region to fulfill the memblock. */
+ memblock_reserve(memory_base, MEM_SIZE);
+
+ ASSERT_EQ(memblock.reserved.cnt, i + 1);
+ ASSERT_EQ(memblock.reserved.total_size, (i + 1) * MEM_SIZE);
+
+ /* Keep the gap so these memory region will not be merged. */
+ memory_base += MEM_SIZE * 2;
+ }
+
+ orig_region = memblock.reserved.regions;
+
+ /* This reserve the 129 memory_region, and makes it double array. */
+ memblock_reserve(memory_base, MEM_SIZE);
+
+ /*
+ * This is the memory region size used by the doubled reserved.regions,
+ * and it has been reserved due to it has been used. The size is used to
+ * calculate the total_size that the memblock.reserved have now.
+ */
+ new_reserved_regions_size = PAGE_ALIGN((INIT_MEMBLOCK_REGIONS * 2) *
+ sizeof(struct memblock_region));
+ /*
+ * The double_array() will find a free memory region as the new
+ * reserved.regions, and the used memory region will be reserved, so
+ * there will be one more region exist in the reserved memblock. And the
+ * one more reserved region's size is new_reserved_regions_size.
+ */
+ ASSERT_EQ(memblock.reserved.cnt, INIT_MEMBLOCK_REGIONS + 1 + 1);
+2 would be fine ^
Yes. It actually is +2. first +1 is the 129th region, second +1 is the
reserved region used by double_array().
+ ASSERT_EQ(memblock.reserved.total_size, (INIT_MEMBLOCK_REGIONS + 1) * MEM_SIZE +
+ new_reserved_regions_size);
+ ASSERT_EQ(memblock.reserved.max, INIT_MEMBLOCK_REGIONS * 2);
+
Can you please elaborate what does the below sequence check?
After the double_array(), we can reserve more memory region. The below
is aimed to check it can reserve more. So this reserve a memory region
with small base which will be put at the first reserved.regions, and I
checked if it will be reserved ok.
+ /* The base is very small, so it should be insert to the first region. */
+ memblock_reserve(r.base, r.size);
+ ASSERT_EQ(memblock.reserved.regions[0].base, r.base);
+ ASSERT_EQ(memblock.reserved.regions[0].size, r.size);
+
+ ASSERT_EQ(memblock.reserved.cnt, INIT_MEMBLOCK_REGIONS + 2 + 1);
+ ASSERT_EQ(memblock.reserved.total_size, (INIT_MEMBLOCK_REGIONS + 2) * MEM_SIZE +
+ new_reserved_regions_size);
+ ASSERT_EQ(memblock.reserved.max, INIT_MEMBLOCK_REGIONS * 2);
+
+ dummy_physical_memory_cleanup();
+
+ /*
+ * The current reserved.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.reserved.regions = orig_region;
+ memblock.reserved.cnt = INIT_MEMBLOCK_REGIONS;
+
+ test_pass_pop();
+
+ return 0;
+}
+
static int memblock_reserve_checks(void)
{
prefix_reset();
@@ -698,6 +784,7 @@ static int memblock_reserve_checks(void)
memblock_reserve_overlap_bottom_check();
memblock_reserve_within_check();
memblock_reserve_twice_check();
+ memblock_reserve_many_check();
prefix_pop();
--
2.34.1
