| Message ID | 20210323135231.24948-7-wangyanan55@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: selftests: some improvement and a new test for kvm page table | expand |
On Tue, Mar 23, 2021 at 09:52:27PM +0800, Yanan Wang wrote: > If we want to have some tests about transparent hugepages, the system > configured THP hugepage size should better be known by the tests, which > can be used for kinds of alignment or guest memory accessing of vcpus... > So it makes sense to add a helper to get the transparent hugepage size. > > With VM_MEM_SRC_ANONYMOUS_THP specified in vm_userspace_mem_region_add(), > we now stat /sys/kernel/mm/transparent_hugepage to check whether THP is > configured in the host kernel before madvise(). Based on this, we can also > read file /sys/kernel/mm/transparent_hugepage/hpage_pmd_size to get THP > hugepage size. > > Signed-off-by: Yanan Wang <wangyanan55@huawei.com> > Reviewed-by: Ben Gardon <bgardon@google.com> > --- > .../testing/selftests/kvm/include/test_util.h | 2 ++ > tools/testing/selftests/kvm/lib/test_util.c | 29 +++++++++++++++++++ > 2 files changed, 31 insertions(+) Reviewed-by: Andrew Jones <drjones@redhat.com>
diff --git a/tools/testing/selftests/kvm/include/test_util.h b/tools/testing/selftests/kvm/include/test_util.h index b7f41399f22c..ef24c76ba89a 100644 --- a/tools/testing/selftests/kvm/include/test_util.h +++ b/tools/testing/selftests/kvm/include/test_util.h @@ -78,6 +78,8 @@ struct vm_mem_backing_src_alias { enum vm_mem_backing_src_type type; }; +bool thp_configured(void); +size_t get_trans_hugepagesz(void); void backing_src_help(void); enum vm_mem_backing_src_type parse_backing_src_type(const char *type_name); diff --git a/tools/testing/selftests/kvm/lib/test_util.c b/tools/testing/selftests/kvm/lib/test_util.c index c7c0627c6842..efc1a7782de0 100644 --- a/tools/testing/selftests/kvm/lib/test_util.c +++ b/tools/testing/selftests/kvm/lib/test_util.c @@ -10,6 +10,7 @@ #include <limits.h> #include <stdlib.h> #include <time.h> +#include <sys/stat.h> #include "linux/kernel.h" #include "test_util.h" @@ -117,6 +118,34 @@ const struct vm_mem_backing_src_alias backing_src_aliases[] = { {"anonymous_hugetlb", VM_MEM_SRC_ANONYMOUS_HUGETLB,}, }; +bool thp_configured(void) +{ + int ret; + struct stat statbuf; + + ret = stat("/sys/kernel/mm/transparent_hugepage", &statbuf); + TEST_ASSERT(ret == 0 || (ret == -1 && errno == ENOENT), + "Error in stating /sys/kernel/mm/transparent_hugepage"); + + return ret == 0; +} + +size_t get_trans_hugepagesz(void) +{ + size_t size; + FILE *f; + + TEST_ASSERT(thp_configured(), "THP is not configured in host kernel"); + + f = fopen("/sys/kernel/mm/transparent_hugepage/hpage_pmd_size", "r"); + TEST_ASSERT(f != NULL, "Error in opening transparent_hugepage/hpage_pmd_size"); + + fscanf(f, "%ld", &size); + fclose(f); + + return size; +} + void backing_src_help(void) { int i;