On 2021/3/12 19:40, Andrew Jones wrote:
On Tue, Mar 02, 2021 at 08:57:48PM +0800, Yanan Wang wrote:
If HUGETLB is configured in the host kernel, then we can know the system default hugetlb page size through *cat /proc/meminfo*. Otherwise, we will not see the information of hugetlb pages in file /proc/meminfo if it's not configured. So add a helper to determine whether HUGETLB is configured and then get the default page size by reading /proc/meminfo.
This helper can be useful when a program wants to use the default hugetlb pages of the system and doesn't know the default page size.
Signed-off-by: Yanan Wang wangyanan55@huawei.com
.../testing/selftests/kvm/include/test_util.h | 1 + tools/testing/selftests/kvm/lib/test_util.c | 27 +++++++++++++++++++ 2 files changed, 28 insertions(+)
diff --git a/tools/testing/selftests/kvm/include/test_util.h b/tools/testing/selftests/kvm/include/test_util.h index ef24c76ba89a..e087174eefe5 100644 --- a/tools/testing/selftests/kvm/include/test_util.h +++ b/tools/testing/selftests/kvm/include/test_util.h @@ -80,6 +80,7 @@ struct vm_mem_backing_src_alias { bool thp_configured(void); size_t get_trans_hugepagesz(void); +size_t get_def_hugetlb_pagesz(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 f2d133f76c67..80d68dbd72d2 100644 --- a/tools/testing/selftests/kvm/lib/test_util.c +++ b/tools/testing/selftests/kvm/lib/test_util.c @@ -153,6 +153,33 @@ size_t get_trans_hugepagesz(void) return size; } +size_t get_def_hugetlb_pagesz(void) +{
- char buf[64];
- const char *tag = "Hugepagesize:";
- FILE *f;
- f = fopen("/proc/meminfo", "r");
- TEST_ASSERT(f != NULL, "Error in opening /proc/meminfo: %d", errno);
- while (fgets(buf, sizeof(buf), f) != NULL) {
if (strstr(buf, tag) == buf) {fclose(f);return strtoull(buf + strlen(tag), NULL, 10) << 10;}- }
- if (feof(f)) {
fclose(f);TEST_FAIL("HUGETLB is not configured in host kernel");- } else {
fclose(f);TEST_FAIL("Error in reading /proc/meminfo: %d", errno);- }
fclose() can be factored out.
- return 0;
+}
- void backing_src_help(void) { int i;
-- 2.23.0
Besides the fclose comment and the same errno comment as the previous patch
I will fix it and add your R-b in this patch.
Thanks, Yanan
Reviewed-by: Andrew Jones drjones@redhat.com
.