From 5579fa682a3411e5ed58bde35af5128f1044a4b9 Mon Sep 17 00:00:00 2001 From: Yanan Wang Date: Tue, 30 Mar 2021 16:08:53 +0800 Subject: KVM: selftests: Add a helper to get system default hugetlb page size 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 Reviewed-by: Andrew Jones Message-Id: <20210330080856.14940-8-wangyanan55@huawei.com> Signed-off-by: Paolo Bonzini --- tools/testing/selftests/kvm/lib/test_util.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) (limited to 'tools/testing/selftests/kvm/lib/test_util.c') diff --git a/tools/testing/selftests/kvm/lib/test_util.c b/tools/testing/selftests/kvm/lib/test_util.c index 9830b2bcd068..bd718c9fb92e 100644 --- a/tools/testing/selftests/kvm/lib/test_util.c +++ b/tools/testing/selftests/kvm/lib/test_util.c @@ -146,6 +146,31 @@ 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"); + + 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)) + TEST_FAIL("HUGETLB is not configured in host kernel"); + else + TEST_FAIL("Error in reading /proc/meminfo"); + + fclose(f); + return 0; +} + void backing_src_help(void) { int i; -- cgit v1.2.3