selftests/mm: protection_keys: use library code for HugeTLB setup

protection_keys open codes setup of HugeTLB pages.

Replace it with the library functions from hugepage_setup.

Replace exit() calls with _exit() to avoid restoring HugeTLB settings in
the middle of test.

Link: https://lore.kernel.org/20260511162840.375890-48-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Tested-by: Luiz Capitulino <luizcap@redhat.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Donet Tom <donettom@linux.ibm.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Liam Howlett <liam@infradead.org>
Cc: Li Wang <li.wang@linux.dev>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Sarthak Sharma <sarthak.sharma@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/tools/testing/selftests/mm/protection_keys.c b/tools/testing/selftests/mm/protection_keys.c
index 4e4aa3b326c169f0b1218ecc5b9b6973917cab35..9a6d954ee37126e07c49f7271cd20a11e24b0621 100644 (file)
--- a/tools/testing/selftests/mm/protection_keys.c
+++ b/tools/testing/selftests/mm/protection_keys.c
@@ -62,6 +62,7 @@ noinline int read_ptr(int *ptr)
        return *ptr;
 }
 
+#if CONTROL_TRACING > 0
 static void cat_into_file(char *str, char *file)
 {
        int fd = open(file, O_RDWR);
@@ -87,7 +88,6 @@ static void cat_into_file(char *str, char *file)
        close(fd);
 }
 
-#if CONTROL_TRACING > 0
 static int warned_tracing;
 static int tracing_root_ok(void)
 {
@@ -710,50 +710,28 @@ static void *malloc_pkey_anon_huge(long size, int prot, u16 pkey)
 }
 
 static int hugetlb_setup_ok;
-#define SYSFS_FMT_NR_HUGE_PAGES "/sys/kernel/mm/hugepages/hugepages-%ldkB/nr_hugepages"
 #define GET_NR_HUGE_PAGES 10
 static void setup_hugetlbfs(void)
 {
-       int err;
-       int fd;
-       char buf[256];
-       long hpagesz_kb;
-       long hpagesz_mb;
+       long hpagesz_mb = HPAGE_SIZE / 1024 / 1024;
+       unsigned long free_pages;
 
        if (geteuid() != 0) {
                ksft_print_msg("WARNING: not run as root, can not do hugetlb test\n");
                return;
        }
 
-       cat_into_file(__stringify(GET_NR_HUGE_PAGES), "/proc/sys/vm/nr_hugepages");
-
        /*
-        * Now go make sure that we got the pages and that they
+        * Make sure that we got the pages and that they
         * are PMD-level pages. Someone might have made PUD-level
         * pages the default.
         */
-       hpagesz_kb = HPAGE_SIZE / 1024;
-       hpagesz_mb = hpagesz_kb / 1024;
-       sprintf(buf, SYSFS_FMT_NR_HUGE_PAGES, hpagesz_kb);
-       fd = open(buf, O_RDONLY);
-       if (fd < 0) {
-               fprintf(stderr, "opening sysfs %ldM hugetlb config: %s\n",
-                       hpagesz_mb, strerror(errno));
-               return;
-       }
-
-       /* -1 to guarantee leaving the trailing \0 */
-       err = read(fd, buf, sizeof(buf)-1);
-       close(fd);
-       if (err <= 0) {
-               fprintf(stderr, "reading sysfs %ldM hugetlb config: %s\n",
-                       hpagesz_mb, strerror(errno));
-               return;
-       }
-
-       if (atoi(buf) != GET_NR_HUGE_PAGES) {
-               fprintf(stderr, "could not confirm %ldM pages, got: '%s' expected %d\n",
-                       hpagesz_mb, buf, GET_NR_HUGE_PAGES);
+       hugetlb_save_settings();
+       hugetlb_set_nr_pages(HPAGE_SIZE, GET_NR_HUGE_PAGES);
+       free_pages = hugetlb_free_pages(HPAGE_SIZE);
+       if (free_pages < GET_NR_HUGE_PAGES) {
+               ksft_print_msg("could not confirm %ldM pages, got: '%lu' expected %d\n",
+                              hpagesz_mb, free_pages, GET_NR_HUGE_PAGES);
                return;
        }
 
@@ -1130,7 +1108,7 @@ static void become_child(void)
                /* in the child */
                return;
        }
-       exit(0);
+       _exit(0);
 }
 
 /* Assumes that all pkeys other than 'pkey' are unallocated */
@@ -1509,18 +1487,18 @@ static void test_ptrace_modifies_pkru(int *ptr, u16 pkey)
                 * checking
                 */
                if (__read_pkey_reg() != new_pkru)
-                       exit(1);
+                       _exit(1);
 
                /* Stop and allow the tracer to clear XSTATE_BV for PKRU */
                raise(SIGSTOP);
 
                if (__read_pkey_reg() != 0)
-                       exit(1);
+                       _exit(1);
 
                /* Stop and allow the tracer to examine PKRU */
                raise(SIGSTOP);
 
-               exit(0);
+               _exit(0);
        }
 
        pkey_assert(child == waitpid(child, &status, 0));