[PATCH 22/53] selftests/mm: move HugeTLB helpers to hugepage_settings

Mike Rapoport
2026-04-06T14:19:57Z

Move library functions that abstract HugeTLB /proc and /sysfs access
from vm_util to hugepage_settings.

This will help creating common helpers that save and restore HugeTLB and
THP settings.

Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
---
tools/testing/selftests/mm/gup_longterm.c | 1 +
tools/testing/selftests/mm/hmm-tests.c | 2 +-
.../testing/selftests/mm/hugepage_settings.c | 68 +++++++++++++++++++
.../testing/selftests/mm/hugepage_settings.h | 8 +++
tools/testing/selftests/mm/hugetlb-madvise.c | 1 +
tools/testing/selftests/mm/hugetlb-mmap.c | 1 +
tools/testing/selftests/mm/hugetlb-vmemmap.c | 1 +
tools/testing/selftests/mm/hugetlb_dio.c | 1 +
.../selftests/mm/hugetlb_fault_after_madv.c | 1 +
.../selftests/mm/hugetlb_madv_vs_map.c | 1 +
tools/testing/selftests/mm/thuge-gen.c | 1 +
tools/testing/selftests/mm/uffd-common.h | 1 +
.../selftests/mm/va_high_addr_switch.c | 1 +
tools/testing/selftests/mm/vm_util.c | 66 ------------------
tools/testing/selftests/mm/vm_util.h | 3 -
15 files changed, 87 insertions(+), 70 deletions(-)

diff --git a/tools/testing/selftests/mm/gup_longterm.c b/tools/testing/selftests/mm/gup_longterm.c
index f61150d28eb2..ab4eaf4feb7c 100644
--- a/tools/testing/selftests/mm/gup_longterm.c
+++ b/tools/testing/selftests/mm/gup_longterm.c
@@ -29,6 +29,7 @@
#include "../../../../mm/gup_test.h"
#include "kselftest.h"
#include "vm_util.h"
+#include "hugepage_settings.h"

static size_t pagesize;
static int nr_hugetlbsizes;
diff --git a/tools/testing/selftests/mm/hmm-tests.c b/tools/testing/selftests/mm/hmm-tests.c
index 788689497e92..409b11cad4bc 100644
--- a/tools/testing/selftests/mm/hmm-tests.c
+++ b/tools/testing/selftests/mm/hmm-tests.c
@@ -11,6 +11,7 @@
*/

#include "kselftest_harness.h"
+#include "hugepage_settings.h"

#include <errno.h>
#include <fcntl.h>
@@ -27,7 +28,6 @@
#include <sys/ioctl.h>
#include <sys/time.h>

-
/*
* This is a private UAPI to the kernel test module so it isn't exported
* in the usual include/uapi/... directory.
diff --git a/tools/testing/selftests/mm/hugepage_settings.c b/tools/testing/selftests/mm/hugepage_settings.c
index 87ecb309b430..ebaa621c45c6 100644
--- a/tools/testing/selftests/mm/hugepage_settings.c
+++ b/tools/testing/selftests/mm/hugepage_settings.c
@@ -1,7 +1,9 @@
// SPDX-License-Identifier: GPL-2.0
+#include <dirent.h>
#include <fcntl.h>
#include <limits.h>
#include <signal.h>
+#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
@@ -396,3 +398,69 @@ bool thp_is_enabled(void)
/* THP is considered enabled if it's either "always" or "madvise" */
return mode == 1 || mode == 3;
}
+
+int detect_hugetlb_page_sizes(size_t sizes[], int max)
+{
+ DIR *dir = opendir("/sys/kernel/mm/hugepages/");
+ int count = 0;
+
+ if (!dir)
+ return 0;
+
+ while (count < max) {
+ struct dirent *entry = readdir(dir);
+ size_t kb;
+
+ if (!entry)
+ break;
+ if (entry->d_type != DT_DIR)
+ continue;
+ if (sscanf(entry->d_name, "hugepages-%zukB", &kb) != 1)
+ continue;
+ sizes[count++] = kb * 1024;
+ ksft_print_msg("[INFO] detected hugetlb page size: %zu KiB\n",
+ kb);
+ }
+ closedir(dir);
+ return count;
+}
+
+unsigned long default_huge_page_size(void)
+{
+ unsigned long hps = 0;
+ char *line = NULL;
+ size_t linelen = 0;
+ FILE *f = fopen("/proc/meminfo", "r");
+
+ if (!f)
+ return 0;
+ while (getline(&line, &linelen, f) > 0) {
+ if (sscanf(line, "Hugepagesize: %lu kB", &hps) == 1) {
+ hps <<= 10;
+ break;
+ }
+ }
+
+ free(line);
+ fclose(f);
+ return hps;
+}
+
+unsigned long get_free_hugepages(void)
+{
+ unsigned long fhp = 0;
+ char *line = NULL;
+ size_t linelen = 0;
+ FILE *f = fopen("/proc/meminfo", "r");
+
+ if (!f)
+ return fhp;
+ while (getline(&line, &linelen, f) > 0) {
+ if (sscanf(line, "HugePages_Free: %lu", &fhp) == 1)
+ break;
+ }
+
+ free(line);
+ fclose(f);
+ return fhp;
+}
diff --git a/tools/testing/selftests/mm/hugepage_settings.h b/tools/testing/selftests/mm/hugepage_settings.h
index 7748a9009191..320b97e768e8 100644
--- a/tools/testing/selftests/mm/hugepage_settings.h
+++ b/tools/testing/selftests/mm/hugepage_settings.h
@@ -6,6 +6,8 @@
#include <stddef.h>
#include <stdint.h>

+/* Transparent Huge Pages (THP) */
+
enum thp_enabled {
THP_NEVER,
THP_ALWAYS,
@@ -86,4 +88,10 @@ unsigned long thp_shmem_supported_orders(void);
bool thp_available(void);
bool thp_is_enabled(void);

+/* HugeTLB */
+
+int detect_hugetlb_page_sizes(size_t sizes[], int max);
+unsigned long default_huge_page_size(void);
+unsigned long get_free_hugepages(void);
+
#endif /* __THP_SETTINGS_H__ */
diff --git a/tools/testing/selftests/mm/hugetlb-madvise.c b/tools/testing/selftests/mm/hugetlb-madvise.c
index 4c6c346a3af5..316384d919db 100644
--- a/tools/testing/selftests/mm/hugetlb-madvise.c
+++ b/tools/testing/selftests/mm/hugetlb-madvise.c
@@ -20,6 +20,7 @@
#include <fcntl.h>
#include "vm_util.h"
#include "kselftest.h"
+#include "hugepage_settings.h"

#define MIN_FREE_PAGES 20
#define NR_HUGE_PAGES 10 /* common number of pages to map/allocate */
diff --git a/tools/testing/selftests/mm/hugetlb-mmap.c b/tools/testing/selftests/mm/hugetlb-mmap.c
index 71a444d8b1cb..5be68fbc36dc 100644
--- a/tools/testing/selftests/mm/hugetlb-mmap.c
+++ b/tools/testing/selftests/mm/hugetlb-mmap.c
@@ -17,6 +17,7 @@
#include <fcntl.h>
#include "vm_util.h"
#include "kselftest.h"
+#include "hugepage_settings.h"

#define LENGTH (256UL*1024*1024)
#define PROTECTION (PROT_READ | PROT_WRITE)
diff --git a/tools/testing/selftests/mm/hugetlb-vmemmap.c b/tools/testing/selftests/mm/hugetlb-vmemmap.c
index 485a6978b40f..af5786bebfd1 100644
--- a/tools/testing/selftests/mm/hugetlb-vmemmap.c
+++ b/tools/testing/selftests/mm/hugetlb-vmemmap.c
@@ -11,6 +11,7 @@
#include <sys/mman.h>
#include <fcntl.h>
#include "vm_util.h"
+#include "hugepage_settings.h"

#define PAGE_COMPOUND_HEAD (1UL << 15)
#define PAGE_COMPOUND_TAIL (1UL << 16)
diff --git a/tools/testing/selftests/mm/hugetlb_dio.c b/tools/testing/selftests/mm/hugetlb_dio.c
index 31a054fa8134..81e3f7bc8e76 100644
--- a/tools/testing/selftests/mm/hugetlb_dio.c
+++ b/tools/testing/selftests/mm/hugetlb_dio.c
@@ -20,6 +20,7 @@
#include <sys/syscall.h>
#include "vm_util.h"
#include "kselftest.h"
+#include "hugepage_settings.h"

#ifndef STATX_DIOALIGN
#define STATX_DIOALIGN 0x00002000U
diff --git a/tools/testing/selftests/mm/hugetlb_fault_after_madv.c b/tools/testing/selftests/mm/hugetlb_fault_after_madv.c
index b4b257775b74..abc3904c5268 100644
--- a/tools/testing/selftests/mm/hugetlb_fault_after_madv.c
+++ b/tools/testing/selftests/mm/hugetlb_fault_after_madv.c
@@ -10,6 +10,7 @@

#include "vm_util.h"
#include "kselftest.h"
+#include "hugepage_settings.h"

#define INLOOP_ITER 100

diff --git a/tools/testing/selftests/mm/hugetlb_madv_vs_map.c b/tools/testing/selftests/mm/hugetlb_madv_vs_map.c
index c7105c6d319b..ac60b4f18784 100644
--- a/tools/testing/selftests/mm/hugetlb_madv_vs_map.c
+++ b/tools/testing/selftests/mm/hugetlb_madv_vs_map.c
@@ -25,6 +25,7 @@
#include <unistd.h>

#include "vm_util.h"
+#include "hugepage_settings.h"

#define INLOOP_ITER 100

diff --git a/tools/testing/selftests/mm/thuge-gen.c b/tools/testing/selftests/mm/thuge-gen.c
index 77813d34dcc2..1007bc8aa57c 100644
--- a/tools/testing/selftests/mm/thuge-gen.c
+++ b/tools/testing/selftests/mm/thuge-gen.c
@@ -28,6 +28,7 @@
#include <string.h>
#include "vm_util.h"
#include "kselftest.h"
+#include "hugepage_settings.h"

#if !defined(MAP_HUGETLB)
#define MAP_HUGETLB 0x40000
diff --git a/tools/testing/selftests/mm/uffd-common.h b/tools/testing/selftests/mm/uffd-common.h
index 844a85ab31eb..6c5aca9cb63e 100644
--- a/tools/testing/selftests/mm/uffd-common.h
+++ b/tools/testing/selftests/mm/uffd-common.h
@@ -37,6 +37,7 @@

#include "kselftest.h"
#include "vm_util.h"
+#include "hugepage_settings.h"

#define UFFD_FLAGS (O_CLOEXEC | O_NONBLOCK | UFFD_USER_MODE_ONLY)

diff --git a/tools/testing/selftests/mm/va_high_addr_switch.c b/tools/testing/selftests/mm/va_high_addr_switch.c
index 5741fd057640..d42ad50eb2d3 100644
--- a/tools/testing/selftests/mm/va_high_addr_switch.c
+++ b/tools/testing/selftests/mm/va_high_addr_switch.c
@@ -11,6 +11,7 @@

#include "vm_util.h"
#include "kselftest.h"
+#include "hugepage_settings.h"

/*
* The hint addr value is used to allocate addresses
diff --git a/tools/testing/selftests/mm/vm_util.c b/tools/testing/selftests/mm/vm_util.c
index db94564f4431..e62e2a473123 100644
--- a/tools/testing/selftests/mm/vm_util.c
+++ b/tools/testing/selftests/mm/vm_util.c
@@ -291,53 +291,6 @@ int64_t allocate_transhuge(void *ptr, int pagemap_fd)
return -1;
}

-unsigned long default_huge_page_size(void)
-{
- unsigned long hps = 0;
- char *line = NULL;
- size_t linelen = 0;
- FILE *f = fopen("/proc/meminfo", "r");
-
- if (!f)
- return 0;
- while (getline(&line, &linelen, f) > 0) {
- if (sscanf(line, "Hugepagesize: %lu kB", &hps) == 1) {
- hps <<= 10;
- break;
- }
- }
-
- free(line);
- fclose(f);
- return hps;
-}
-
-int detect_hugetlb_page_sizes(size_t sizes[], int max)
-{
- DIR *dir = opendir("/sys/kernel/mm/hugepages/");
- int count = 0;
-
- if (!dir)
- return 0;
-
- while (count < max) {
- struct dirent *entry = readdir(dir);
- size_t kb;
-
- if (!entry)
- break;
- if (entry->d_type != DT_DIR)
- continue;
- if (sscanf(entry->d_name, "hugepages-%zukB", &kb) != 1)
- continue;
- sizes[count++] = kb * 1024;
- ksft_print_msg("[INFO] detected hugetlb page size: %zu KiB\n",
- kb);
- }
- closedir(dir);
- return count;
-}
-
int pageflags_get(unsigned long pfn, int kpageflags_fd, uint64_t *flags)
{
size_t count;
@@ -396,25 +349,6 @@ int uffd_unregister(int uffd, void *addr, uint64_t len)
return ret;
}

-unsigned long get_free_hugepages(void)
-{
- unsigned long fhp = 0;
- char *line = NULL;
- size_t linelen = 0;
- FILE *f = fopen("/proc/meminfo", "r");
-
- if (!f)
- return fhp;
- while (getline(&line, &linelen, f) > 0) {
- if (sscanf(line, "HugePages_Free: %lu", &fhp) == 1)
- break;
- }
-
- free(line);
- fclose(f);
- return fhp;
-}
-
static bool check_vmflag(void *addr, const char *flag)
{
char buffer[MAX_LINE_LENGTH];
diff --git a/tools/testing/selftests/mm/vm_util.h b/tools/testing/selftests/mm/vm_util.h
index 1a07305ceff4..195bf2e26792 100644
--- a/tools/testing/selftests/mm/vm_util.h
+++ b/tools/testing/selftests/mm/vm_util.h
@@ -94,8 +94,6 @@ bool check_huge_anon(void *addr, int nr_hpages, uint64_t hpage_size);
bool check_huge_file(void *addr, int nr_hpages, uint64_t hpage_size);
bool check_huge_shmem(void *addr, int nr_hpages, uint64_t hpage_size);
int64_t allocate_transhuge(void *ptr, int pagemap_fd);
-unsigned long default_huge_page_size(void);
-int detect_hugetlb_page_sizes(size_t sizes[], int max);
int pageflags_get(unsigned long pfn, int kpageflags_fd, uint64_t *flags);

int uffd_register(int uffd, void *addr, uint64_t len,
@@ -103,7 +101,6 @@ int uffd_register(int uffd, void *addr, uint64_t len,
int uffd_unregister(int uffd, void *addr, uint64_t len);
int uffd_register_with_ioctls(int uffd, void *addr, uint64_t len,
bool miss, bool wp, bool minor, uint64_t *ioctls);
-unsigned long get_free_hugepages(void);
bool check_vmflag_io(void *addr);
bool check_vmflag_pfnmap(void *addr);
bool check_vmflag_guard(void *addr);
--
2.53.0