On Wed, Aug 27, 2025, Shivank Garg wrote:
Add tests for NUMA memory policy binding and NUMA aware allocation in guest_memfd. This extends the existing selftests by adding proper validation for:
- KVM GMEM set_policy and get_policy() vm_ops functionality using mbind() and get_mempolicy()
- NUMA policy application before and after memory allocation
These tests help ensure NUMA support for guest_memfd works correctly.
Signed-off-by: Shivank Garg shivankg@amd.com
tools/testing/selftests/kvm/Makefile.kvm | 1 + .../testing/selftests/kvm/guest_memfd_test.c | 121 ++++++++++++++++++ 2 files changed, 122 insertions(+)
diff --git a/tools/testing/selftests/kvm/Makefile.kvm b/tools/testing/selftests/kvm/Makefile.kvm index 90f03f00cb04..c46cef2a7cd7 100644 --- a/tools/testing/selftests/kvm/Makefile.kvm +++ b/tools/testing/selftests/kvm/Makefile.kvm @@ -275,6 +275,7 @@ pgste-option = $(call try-run, echo 'int main(void) { return 0; }' | \ $(CC) -Werror -Wl$(comma)--s390-pgste -x c - -o "$$TMP",-Wl$(comma)--s390-pgste) LDLIBS += -ldl +LDLIBS += -lnuma
Hrm, this is going to be very annoying. I don't have libnuma-dev installed on any of my <too many> systems, and I doubt I'm alone. Installing the package is trivial, but I'm a little wary of foisting that requirement on all KVM developers and build bots.
I'd be especially curious what ARM and RISC-V think, as NUMA is likely a bit less prevelant there.
LDFLAGS += -pthread $(no-pie-option) $(pgste-option) LIBKVM_C := $(filter %.c,$(LIBKVM)) diff --git a/tools/testing/selftests/kvm/guest_memfd_test.c b/tools/testing/selftests/kvm/guest_memfd_test.c index b3ca6737f304..9640d04ec293 100644 --- a/tools/testing/selftests/kvm/guest_memfd_test.c +++ b/tools/testing/selftests/kvm/guest_memfd_test.c @@ -7,6 +7,8 @@ #include <stdlib.h> #include <string.h> #include <unistd.h> +#include <numa.h> +#include <numaif.h> #include <errno.h> #include <stdio.h> #include <fcntl.h> @@ -19,6 +21,7 @@ #include <sys/mman.h> #include <sys/types.h> #include <sys/stat.h> +#include <sys/syscall.h> #include "kvm_util.h" #include "test_util.h" @@ -72,6 +75,122 @@ static void test_mmap_supported(int fd, size_t page_size, size_t total_size) TEST_ASSERT(!ret, "munmap() should succeed."); } +#define TEST_REQUIRE_NUMA_MULTIPLE_NODES() \
- TEST_REQUIRE(numa_available() != -1 && numa_max_node() >= 1)
Using TEST_REQUIRE() here will result in skipping the _entire_ test. Ideally this test would use fixtures so that each testcase can run in a child process and thus can use TEST_REQUIRE(), but that's a conversion for another day.
Easiest thing would probably be to turn this into a common helper and then bail early.
diff --git a/tools/testing/selftests/kvm/guest_memfd_test.c b/tools/testing/selftests/kvm/guest_memfd_test.c index 9640d04ec293..6acb186e5300 100644 --- a/tools/testing/selftests/kvm/guest_memfd_test.c +++ b/tools/testing/selftests/kvm/guest_memfd_test.c @@ -7,7 +7,6 @@ #include <stdlib.h> #include <string.h> #include <unistd.h> -#include <numa.h> #include <numaif.h> #include <errno.h> #include <stdio.h> @@ -75,9 +74,6 @@ static void test_mmap_supported(int fd, size_t page_size, size_t total_size) TEST_ASSERT(!ret, "munmap() should succeed."); }
-#define TEST_REQUIRE_NUMA_MULTIPLE_NODES() \ - TEST_REQUIRE(numa_available() != -1 && numa_max_node() >= 1) - static void test_mbind(int fd, size_t page_size, size_t total_size) { unsigned long nodemask = 1; /* nid: 0 */ @@ -87,7 +83,8 @@ static void test_mbind(int fd, size_t page_size, size_t total_size) char *mem; int ret;
- TEST_REQUIRE_NUMA_MULTIPLE_NODES(); + if (!is_multi_numa_node_system()) + return;
mem = mmap(NULL, total_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); TEST_ASSERT(mem != MAP_FAILED, "mmap for mbind test should succeed"); @@ -136,7 +133,8 @@ static void test_numa_allocation(int fd, size_t page_size, size_t total_size) char *mem; int ret, i;
- TEST_REQUIRE_NUMA_MULTIPLE_NODES(); + if (!is_multi_numa_node_system()) + return;
/* Clean slate: deallocate all file space, if any */ ret = fallocate(fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, 0, total_size); diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h index 23a506d7eca3..d7051607e6bf 100644 --- a/tools/testing/selftests/kvm/include/kvm_util.h +++ b/tools/testing/selftests/kvm/include/kvm_util.h @@ -21,6 +21,7 @@ #include <sys/eventfd.h> #include <sys/ioctl.h>
+#include <numa.h> #include <pthread.h>
#include "kvm_util_arch.h" @@ -633,6 +634,11 @@ static inline bool is_smt_on(void) return false; }
+static inline bool is_multi_numa_node_system(void) +{ + return numa_available() != -1 && numa_max_node() >= 1; +} + void vm_create_irqchip(struct kvm_vm *vm);
static inline int __vm_create_guest_memfd(struct kvm_vm *vm, uint64_t size,