When the virtual address range selftest is run on arm64 and x86 platforms,
it is observed that both the low and high VA range iterations are skipped
when the MAP_CHUNK_SIZE is set to 16GB. The MAP_CHUNK_SIZE is changed to
1GB to resolve this issue, following which support for arm64 platform is
added by changing the NR_CHUNKS_HIGH for aarch64 to accommodate up to 4PB
of virtual address space allocation requests. Dynamic memory allocation
of array holding addresses is introduced to prevent overflow of the stack.
Finally, the overcommit_policy is set as OVERCOMMIT_ALWAYS to prevent the
kernel from denying a memory allocation request based on a platform's
physical memory availability.
This series has been tested on 6.3.0-rc1 mainline kernel, both on arm64
and x86 platforms.
Changes in V2:
- Changed subject line to start with "selftest/mm", to maintain
specificity.
Changes in V1:
https://lore.kernel.org/all/[email protected]/
Cc: Andrew Morton <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Shuah Khan <[email protected]>
Cc: [email protected]
Cc: [email protected]
Chaitanya S Prakash (3):
selftests/mm: Change MAP_CHUNK_SIZE
selftests/mm: Change NR_CHUNKS_HIGH for aarch64
selftests/mm: Set overcommit_policy as OVERCOMMIT_ALWAYS
tools/testing/selftests/mm/run_vmtests.sh | 8 +++++++
.../selftests/mm/virtual_address_range.c | 24 +++++++++++++------
2 files changed, 25 insertions(+), 7 deletions(-)
--
2.30.2
Although there is a provision for 52 bit VA on arm64 platform, it remains
unutilised and higher addresses are not allocated. In order to accommodate
4PB [2^52] virtual address space where supported, NR_CHUNKS_HIGH is changed
accordingly.
Array holding addresses is changed from static allocation to dynamic
allocation to accommodate its voluminous nature which otherwise might
overflow the stack.
Cc: Andrew Morton <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Shuah Khan <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Chaitanya S Prakash <[email protected]>
---
tools/testing/selftests/mm/virtual_address_range.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)
diff --git a/tools/testing/selftests/mm/virtual_address_range.c b/tools/testing/selftests/mm/virtual_address_range.c
index 50564512c5ee..bae0ceaf95b1 100644
--- a/tools/testing/selftests/mm/virtual_address_range.c
+++ b/tools/testing/selftests/mm/virtual_address_range.c
@@ -36,13 +36,15 @@
* till it reaches 512TB. One with size 128TB and the
* other being 384TB.
*
- * On Arm64 the address space is 256TB and no high mappings
- * are supported so far.
+ * On Arm64 the address space is 256TB and support for
+ * high mappings up to 4PB virtual address space has
+ * been added.
*/
#define NR_CHUNKS_128TB ((128 * SZ_1TB) / MAP_CHUNK_SIZE) /* Number of chunks for 128TB */
#define NR_CHUNKS_256TB (NR_CHUNKS_128TB * 2UL)
#define NR_CHUNKS_384TB (NR_CHUNKS_128TB * 3UL)
+#define NR_CHUNKS_3840TB (NR_CHUNKS_128TB * 30UL)
#define ADDR_MARK_128TB (1UL << 47) /* First address beyond 128TB */
#define ADDR_MARK_256TB (1UL << 48) /* First address beyond 256TB */
@@ -51,7 +53,7 @@
#define HIGH_ADDR_MARK ADDR_MARK_256TB
#define HIGH_ADDR_SHIFT 49
#define NR_CHUNKS_LOW NR_CHUNKS_256TB
-#define NR_CHUNKS_HIGH 0
+#define NR_CHUNKS_HIGH NR_CHUNKS_3840TB
#else
#define HIGH_ADDR_MARK ADDR_MARK_128TB
#define HIGH_ADDR_SHIFT 48
@@ -101,7 +103,7 @@ static int validate_lower_address_hint(void)
int main(int argc, char *argv[])
{
char *ptr[NR_CHUNKS_LOW];
- char *hptr[NR_CHUNKS_HIGH];
+ char **hptr;
char *hint;
unsigned long i, lchunks, hchunks;
@@ -119,6 +121,9 @@ int main(int argc, char *argv[])
return 1;
}
lchunks = i;
+ hptr = (char **) calloc(NR_CHUNKS_HIGH, sizeof(char *));
+ if (hptr == NULL)
+ return 1;
for (i = 0; i < NR_CHUNKS_HIGH; i++) {
hint = hind_addr();
@@ -139,5 +144,6 @@ int main(int argc, char *argv[])
for (i = 0; i < hchunks; i++)
munmap(hptr[i], MAP_CHUNK_SIZE);
+ free(hptr);
return 0;
}
--
2.30.2