On Fri, Nov 16, 2018 at 01:50:55PM +0200, Ahmed Abd El Mawgood wrote:
From: Ahmed Abd El Mawgood ahmedsoliman@mena.vt.edu
madvise() returns -1 without CONFIG_TRANSPARENT_HUGEPAGE=y. That would trigger asserts when checking for return value of madvice. Following similar decision to [1]. I thought it is ok to assume that madvise() MADV_NOHUGEPAGE failures implies that THP is not supported by host kernel.
Other options was to check for Transparent Huge Page support in /sys/kernel/mm/transparent_hugepage/enabled.
-- links -- [1] https://lists.gnu.org/archive/html/qemu-devel/2015-11/msg04514.html
Signed-off-by: Ahmed Abd El Mawgood ahmedsoliman@mena.vt.edu
tools/testing/selftests/kvm/lib/kvm_util.c | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-)
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c index 1b41e71283d5..437c5bb48061 100644 --- a/tools/testing/selftests/kvm/lib/kvm_util.c +++ b/tools/testing/selftests/kvm/lib/kvm_util.c @@ -586,14 +586,23 @@ void vm_userspace_mem_region_add(struct kvm_vm *vm, src_type == VM_MEM_SRC_ANONYMOUS_THP ? huge_page_size : 1); /* As needed perform madvise */
- if (src_type == VM_MEM_SRC_ANONYMOUS || src_type == VM_MEM_SRC_ANONYMOUS_THP) {
- if (src_type == VM_MEM_SRC_ANONYMOUS) {
/** Neglect madvise error because it is ok to not have THP* support in this case.*/madvise(region->host_mem, npages * vm->page_size,MADV_NOHUGEPAGE);- } else if (src_type == VM_MEM_SRC_ANONYMOUS_THP) { ret = madvise(region->host_mem, npages * vm->page_size,
src_type == VM_MEM_SRC_ANONYMOUS ? MADV_NOHUGEPAGE : MADV_HUGEPAGE);
MADV_HUGEPAGE);
" addr: %p\n"" length: 0x%lx\n"" src_type: %x",region->host_mem, npages * vm->page_size, src_type);
"Does the kernel have CONFIG_TRANSPARENT_HUGEPAGE=y\n"" addr: %p\n"" length: 0x%lx\n"" src_type: %x\n",region->host_mem, npages * vm->page_size,src_type);region->unused_phy_pages = sparsebit_alloc(); -- 2.18.1
Reviewed-by: Andrew Jones drjones@redhat.com