From: Yanan Wang Date: Tue, 30 Mar 2021 08:08:52 +0000 (+0800) Subject: KVM: selftests: Add a helper to get system configured THP page size X-Git-Tag: v5.15~1218^2~77 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=3b70c4d128a7781f507fa072d60ce5df3fdfcaa6;p=platform%2Fkernel%2Flinux-starfive.git KVM: selftests: Add a helper to get system configured THP page size 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 Reviewed-by: Ben Gardon Reviewed-by: Andrew Jones Message-Id: <20210330080856.14940-7-wangyanan55@huawei.com> Signed-off-by: Paolo Bonzini --- diff --git a/tools/testing/selftests/kvm/include/test_util.h b/tools/testing/selftests/kvm/include/test_util.h index b7f4139..ef24c76 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 906c955..9830b2b 100644 --- a/tools/testing/selftests/kvm/lib/test_util.c +++ b/tools/testing/selftests/kvm/lib/test_util.c @@ -10,6 +10,7 @@ #include #include #include +#include #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;