On 23.05.19 19:40, Andrew Jones wrote:
On Thu, May 23, 2019 at 06:43:05PM +0200, Thomas Huth wrote:
On s390x, there is a constraint that memory regions have to be aligned to 1M (or running the VM will fail). Introduce a new "alignment" variable in the vm_userspace_mem_region_add() function which now can be used for both, huge page and s390x alignment requirements.
Signed-off-by: Thomas Huth thuth@redhat.com
tools/testing/selftests/kvm/lib/kvm_util.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-)
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c index 08edb8436c47..656df9d5cd4d 100644 --- a/tools/testing/selftests/kvm/lib/kvm_util.c +++ b/tools/testing/selftests/kvm/lib/kvm_util.c @@ -559,6 +559,7 @@ void vm_userspace_mem_region_add(struct kvm_vm *vm, unsigned long pmem_size = 0; struct userspace_mem_region *region; size_t huge_page_size = KVM_UTIL_PGS_PER_HUGEPG * vm->page_size;
- size_t alignment;
TEST_ASSERT((guest_paddr % vm->page_size) == 0, "Guest physical " "address not on a page boundary.\n" @@ -608,9 +609,20 @@ void vm_userspace_mem_region_add(struct kvm_vm *vm, TEST_ASSERT(region != NULL, "Insufficient Memory"); region->mmap_size = npages * vm->page_size;
- /* Enough memory to align up to a huge page. */
+#ifdef __s390x__
- /* On s390x, the host address must be aligned to 1M (due to PGSTEs) */
- alignment = 0x100000;
+#else
- alignment = 1;
+#endif
- if (src_type == VM_MEM_SRC_ANONYMOUS_THP)
region->mmap_size += huge_page_size;
alignment = huge_page_size;I guess s390x won't ever support VM_MEM_SRC_ANONYMOUS_THP? If it does, then we need 'alignment = max(huge_page_size, alignment)'. Actually that might be a nice way to write this anyway for future-proofing.
I can do - alignment = huge_page_size; + alignment = max(huge_page_size, alignment);
when applying.
- /* Add enough memory to align up if necessary */
- if (alignment > 1)
region->mmap_size += alignment;- region->mmap_start = mmap(NULL, region->mmap_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS
@@ -620,9 +632,8 @@ void vm_userspace_mem_region_add(struct kvm_vm *vm, "test_malloc failed, mmap_start: %p errno: %i", region->mmap_start, errno);
- /* Align THP allocation up to start of a huge page. */
- region->host_mem = align(region->mmap_start,
src_type == VM_MEM_SRC_ANONYMOUS_THP ? huge_page_size : 1);
- /* Align host address */
- region->host_mem = align(region->mmap_start, alignment);
/* As needed perform madvise */ if (src_type == VM_MEM_SRC_ANONYMOUS || src_type == VM_MEM_SRC_ANONYMOUS_THP) { -- 2.21.0