[PATCH 1/3] memblock test: Add test to memblock_add() 129th region

From: shaoqin . huang
Date: Sun Aug 21 2022 - 22:34:23 EST


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 valid memory region, and
fake the other memory region, so 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 | 82 ++++++++++++++++++++++++
tools/testing/memblock/tests/common.c | 7 +-
tools/testing/memblock/tests/common.h | 3 +
3 files changed, 90 insertions(+), 2 deletions(-)

diff --git a/tools/testing/memblock/tests/basic_api.c b/tools/testing/memblock/tests/basic_api.c
index 66f46f261e66..c8e201156cdc 100644
--- a/tools/testing/memblock/tests/basic_api.c
+++ b/tools/testing/memblock/tests/basic_api.c
@@ -326,6 +326,87 @@ static int memblock_add_twice_check(void)
return 0;
}

+/*
+ * A test that tries 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 memory_base = SZ_128K;
+
+ PREFIX_PUSH();
+
+ reset_memblock_regions();
+ memblock_allow_resize();
+
+ /*
+ * Add one valid memory region, this will be choosed to be the memory
+ * that new memory.regions occupied.
+ */
+ dummy_physical_memory_init();
+ memblock_add((phys_addr_t)get_memory_block_base(), MEM_SIZE);
+
+ ASSERT_EQ(memblock.memory.cnt, 1);
+ ASSERT_EQ(memblock.memory.total_size, MEM_SIZE);
+
+ for (i = 1; i < INIT_MEMBLOCK_REGIONS; i++) {
+ /* Add some fakes memory region to fulfill the memblock. */
+ memblock_add(memory_base, MEM_SIZE);
+
+ ASSERT_EQ(memblock.memory.cnt, i + 1);
+ ASSERT_EQ(memblock.memory.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.memory.regions;
+
+ /* This adds the 129 memory_region, and makes it double array. */
+ memblock_add((phys_addr_t)memory_base, MEM_SIZE);
+
+ ASSERT_EQ(memblock.memory.cnt, INIT_MEMBLOCK_REGIONS + 1);
+ ASSERT_EQ(memblock.memory.total_size, (INIT_MEMBLOCK_REGIONS + 1) * MEM_SIZE);
+ ASSERT_EQ(memblock.memory.max, INIT_MEMBLOCK_REGIONS * 2);
+
+ ASSERT_EQ(memblock.reserved.cnt, 1);
+ /* This is the size used by new memory.regions. Check it. */
+ ASSERT_EQ(memblock.reserved.total_size, PAGE_ALIGN(INIT_MEMBLOCK_REGIONS * 2 *
+ sizeof(struct memblock_region)));
+
+ /* The base is very small, so it should be insert to the first region. */
+ 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 + 2) * 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();
@@ -339,6 +420,7 @@ static int memblock_add_checks(void)
memblock_add_overlap_bottom_check();
memblock_add_within_check();
memblock_add_twice_check();
+ memblock_add_many_check();

prefix_pop();

diff --git a/tools/testing/memblock/tests/common.c b/tools/testing/memblock/tests/common.c
index e43b2676af81..89684ec00aa2 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 ": "

@@ -75,6 +73,11 @@ void dummy_physical_memory_cleanup(void)
free(memory_block.base);
}

+void *get_memory_block_base(void)
+{
+ return 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 3e7f23d341d7..98b0a0ec629d 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

/**
* ASSERT_EQ():
@@ -70,6 +72,7 @@ void reset_memblock_attributes(void);
void setup_memblock(void);
void dummy_physical_memory_init(void);
void dummy_physical_memory_cleanup(void);
+void *get_memory_block_base(void);
void parse_args(int argc, char **argv);

void test_fail(void);
--
2.34.1