Add an API to query free 2MB hugepages in the system.
Signed-off-by: Vishal Annapurve vannapurve@google.com --- .../testing/selftests/kvm/include/test_util.h | 1 + tools/testing/selftests/kvm/lib/test_util.c | 18 ++++++++++++++++++ 2 files changed, 19 insertions(+)
diff --git a/tools/testing/selftests/kvm/include/test_util.h b/tools/testing/selftests/kvm/include/test_util.h index aea80071f2b8..3d1cc215940a 100644 --- a/tools/testing/selftests/kvm/include/test_util.h +++ b/tools/testing/selftests/kvm/include/test_util.h @@ -122,6 +122,7 @@ struct vm_mem_backing_src_alias { bool thp_configured(void); size_t get_trans_hugepagesz(void); size_t get_def_hugetlb_pagesz(void); +size_t get_free_huge_2mb_pages(void); const struct vm_mem_backing_src_alias *vm_mem_backing_src_alias(uint32_t i); size_t get_backing_src_pagesz(uint32_t i); bool is_backing_src_hugetlb(uint32_t i); diff --git a/tools/testing/selftests/kvm/lib/test_util.c b/tools/testing/selftests/kvm/lib/test_util.c index d33b98bfe8a3..745573023b57 100644 --- a/tools/testing/selftests/kvm/lib/test_util.c +++ b/tools/testing/selftests/kvm/lib/test_util.c @@ -162,6 +162,24 @@ size_t get_trans_hugepagesz(void) return size; }
+size_t get_free_huge_2mb_pages(void) +{ + size_t free_pages; + FILE *f; + int ret; + + f = fopen("/sys/kernel/mm/hugepages/hugepages-2048kB/free_hugepages", "r"); + TEST_ASSERT(f != NULL, "Error in opening hugepages-2048kB/free_hugepages"); + + do { + ret = fscanf(f, "%ld", &free_pages); + } while (errno == EINTR); + TEST_ASSERT(ret < 1, "Error reading hugepages-2048kB/free_hugepages"); + fclose(f); + + return free_pages; +} + size_t get_def_hugetlb_pagesz(void) { char buf[64];