Re: [PATCH v2 1/3] memblock test: Add test to memblock_add() 129th region
From: Huang, Shaoqin
Date: Tue Sep 06 2022 - 11:40:04 EST
On 9/6/2022 8:57 PM, Mike Rapoport wrote:
On Fri, Sep 02, 2022 at 10:39:59AM +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 some valid memory region,
and add it 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 | 91 ++++++++++++++++++++++++
tools/testing/memblock/tests/common.c | 15 +++-
tools/testing/memblock/tests/common.h | 4 ++
3 files changed, 108 insertions(+), 2 deletions(-)
diff --git a/tools/testing/memblock/tests/basic_api.c b/tools/testing/memblock/tests/basic_api.c
index a13a57ba0815..b9877344d3a1 100644
--- a/tools/testing/memblock/tests/basic_api.c
+++ b/tools/testing/memblock/tests/basic_api.c
@@ -423,6 +423,96 @@ 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,
+ };
+ /* Record these allocated memory, they will be free at the end. */
+ phys_addr_t base[INIT_MEMBLOCK_REGIONS + 1];
+
+ PREFIX_PUSH();
+
+ reset_memblock_regions();
+ memblock_allow_resize();
+
+ for (i = 0; i < INIT_MEMBLOCK_REGIONS; i++) {
+ /* Add some memory region to fulfill the memblock. */
+ dummy_physical_memory_init();
+ base[i] = dummy_physical_memory_base();
+ memblock_add(base[i], MEM_SIZE);
Looks like we are going in rounds.
The simulated physical memory is what dummy_physical_memory_init()
allocates. Every memblock_add() may take a range from that "physical
memory" and register it with memblock. There is no need to allocate new
chunk for every memblock_add(), just make sure that
dummy_physical_memory_init() allocates enough memory.
Do you mean dummy_physical_memory_init() a large memory? And split it
into 128 regions to fulfill the memory.regions. If so, we may need to
modify the MEM_SIZE (now is 16K) to a larger size to make double_array()
succeed due to the new memory.regions will occupy 8K memory.
+
+ ASSERT_EQ(memblock.memory.cnt, i + 1);
+ ASSERT_EQ(memblock.memory.total_size, (i + 1) * MEM_SIZE);
+ }
+
+ orig_region = memblock.memory.regions;
+
+ /*
+ * This adds the 129 memory_region, and makes it double array. Now
+ * MEM_SIZE is 16K, which is enough, the doubled array will occupy 8K
+ * memory region, so it must success.
+ */
+ dummy_physical_memory_init();
+ base[i] = dummy_physical_memory_base();
+ memblock_add(base[i], 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)));
+
+ /*
+ * After double array, we want to make sure the memblock.memory.regions
+ * is actually on a valid memory, so we try to add a memory region which
What do you mean by "actually on a valid memory"? How would
memblock_double_array() succeed otherwise?
The code before this line has checked the memblock_double_array()
succeed. I just want to test after it succeed, add a new memory region
into it will still succeed. So the "actually on a valid memory" is a
little confused, I want to modify "After double array, we want to make
sure the memblock.memory.regions is actually on a valid memory" to "The
next we want to test if the memblock_add() still succeed after
memblock_double_array()".
+ * the base is very small, it should be insert to the first region. And
+ * the memory.cnt and memory.total_size will both be changed.
+ * Let's check it.
+ */
+ 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);
+
+ /*
+ * Due to we dummy_physical_memory_init() many memory region in this
+ * test, we need to free it. Instead of expose the memory_block and
+ * directly modify it's base, we pass an array which record all the
+ * memory base that we allocated to this function, and let it to do the
+ * clean job.
+ */
+ dummy_physical_memory_cleanup_many(base, INIT_MEMBLOCK_REGIONS + 1);
+
+ /*
+ * 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 +528,7 @@ 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..1fb347c5c099 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 +82,19 @@ void dummy_physical_memory_cleanup(void)
free(memory_block.base);
}
+void dummy_physical_memory_cleanup_many(phys_addr_t *base, int cnt)
+{
+ for (int i = 0; i < cnt; i++) {
+ memory_block.base = (void *)base[i];
+ dummy_physical_memory_cleanup();
+ }
+}
+
+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..310f0be2b2a2 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 +106,8 @@ void reset_memblock_attributes(void);
void setup_memblock(void);
void dummy_physical_memory_init(void);
void dummy_physical_memory_cleanup(void);
+void dummy_physical_memory_cleanup_many(phys_addr_t *base, int cnt);
+phys_addr_t dummy_physical_memory_base(void);
void parse_args(int argc, char **argv);
void test_fail(void);
--
2.34.1