Test the mmap() flag, the mlockall() flag, and ensure that mlock limits
are respected. Note that the limit test needs to be run a normal user.
Signed-off-by: Eric B Munson <emunson@xxxxxxxxxx>
Cc: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxx>
Cc: linux-mm@xxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: linux-api@xxxxxxxxxxxxxxx
---
tools/testing/selftests/vm/Makefile | 8 +-
tools/testing/selftests/vm/lock-on-fault.c | 145 ++++++++++++++++++++++++++++
tools/testing/selftests/vm/on-fault-limit.c | 47 +++++++++
tools/testing/selftests/vm/run_vmtests | 23 +++++
4 files changed, 222 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/vm/lock-on-fault.c
create mode 100644 tools/testing/selftests/vm/on-fault-limit.c
diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile
index a5ce953..32f3d20 100644
--- a/tools/testing/selftests/vm/Makefile
+++ b/tools/testing/selftests/vm/Makefile
@@ -1,7 +1,13 @@
# Makefile for vm selftests
CFLAGS = -Wall
-BINARIES = hugepage-mmap hugepage-shm map_hugetlb thuge-gen hugetlbfstest
+BINARIES = hugepage-mmap
+BINARIES += hugepage-shm
+BINARIES += hugetlbfstest
+BINARIES += lock-on-fault
+BINARIES += map_hugetlb
+BINARIES += on-fault-limit
+BINARIES += thuge-gen
BINARIES += transhuge-stress
all: $(BINARIES)
diff --git a/tools/testing/selftests/vm/lock-on-fault.c b/tools/testing/selftests/vm/lock-on-fault.c
new file mode 100644
index 0000000..4659303
--- /dev/null
+++ b/tools/testing/selftests/vm/lock-on-fault.c
@@ -0,0 +1,145 @@
+#include <sys/mman.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+
+#ifndef MCL_ONFAULT
+#define MCL_ONFAULT (MCL_FUTURE << 1)
+#endif
+
+#define PRESENT_BIT 0x8000000000000000
+#define PFN_MASK 0x007FFFFFFFFFFFFF
+#define UNEVICTABLE_BIT (1UL << 18)
+
+static int check_pageflags(void *map)
+{
+ FILE *file;
+ unsigned long pfn1;
+ unsigned long pfn2;
+ unsigned long offset1;
+ unsigned long offset2;
+ int ret = 1;
+
+ file = fopen("/proc/self/pagemap", "r");
+ if (!file) {
+ perror("fopen");
+ return ret;
+ }
+ offset1 = (unsigned long)map / getpagesize() * sizeof(unsigned long);
+ offset2 = ((unsigned long)map + getpagesize()) / getpagesize() * sizeof(unsigned long);
+ if (fseek(file, offset1, SEEK_SET)) {
+ perror("fseek");
+ goto out;
+ }
+
+ if (fread(&pfn1, sizeof(unsigned long), 1, file) != 1) {
+ perror("fread");
+ goto out;
+ }
+
+ if (fseek(file, offset2, SEEK_SET)) {
+ perror("fseek");
+ goto out;
+ }
+
+ if (fread(&pfn2, sizeof(unsigned long), 1, file) != 1) {
+ perror("fread");
+ goto out;
+ }
+
+ /* pfn2 should not be present */
+ if (pfn2 & PRESENT_BIT) {
+ printf("page map says 0x%lx\n", pfn2);
+ printf("present is 0x%lx\n", PRESENT_BIT);
+ goto out;
+ }
+
+ /* pfn1 should be present */
+ if ((pfn1 & PRESENT_BIT) == 0) {
+ printf("page map says 0x%lx\n", pfn1);
+ printf("present is 0x%lx\n", PRESENT_BIT);
+ goto out;
+ }
+
+ pfn1 &= PFN_MASK;
+ fclose(file);
+ file = fopen("/proc/kpageflags", "r");
+ if (!file) {
+ perror("fopen");
+ munmap(map, 2 * getpagesize());
+ return ret;
+ }
+
+ if (fseek(file, pfn1 * sizeof(unsigned long), SEEK_SET)) {
+ perror("fseek");
+ goto out;
+ }
+
+ if (fread(&pfn2, sizeof(unsigned long), 1, file) != 1) {
+ perror("fread");
+ goto out;
+ }
+
+ /* pfn2 now contains the entry from kpageflags for the first page, the
+ * unevictable bit should be set */
+ if ((pfn2 & UNEVICTABLE_BIT) == 0) {
+ printf("kpageflags says 0x%lx\n", pfn2);
+ printf("unevictable is 0x%lx\n", UNEVICTABLE_BIT);
+ goto out;
+ }
+
+ ret = 0;
+
+out:
+ fclose(file);
+ return ret;
+}
+
+static int test_mmap(int flags)
+{
+ int ret = 1;
+ void *map;
+
+ map = mmap(NULL, 2 * getpagesize(), PROT_READ | PROT_WRITE, flags, 0, 0);
+ if (map == MAP_FAILED) {
+ perror("mmap()");
+ return ret;
+ }
+
+ /* Write something into the first page to ensure it is present */
+ *(char *)map = 1;
+
+ ret = check_pageflags(map);
+
+ munmap(map, 2 * getpagesize());
+ return ret;
+}
+
+static int test_mlockall(void)
+{
+ int ret = 1;
+
+ if (mlockall(MCL_ONFAULT)) {
+ perror("mlockall");
+ return ret;
+ }
+
+ ret = test_mmap(MAP_PRIVATE | MAP_ANONYMOUS);
+ munlockall();
+ return ret;
+}
+
+#ifndef MAP_LOCKONFAULT
+#define MAP_LOCKONFAULT (MAP_HUGETLB << 1)
+#endif
+
+int main(int argc, char **argv)
+{
+ int ret = 0;
+
+ ret += test_mmap(MAP_PRIVATE | MAP_ANONYMOUS | MAP_LOCKONFAULT);
+ ret += test_mlockall();
+ return ret;
+}
diff --git a/tools/testing/selftests/vm/on-fault-limit.c b/tools/testing/selftests/vm/on-fault-limit.c
new file mode 100644
index 0000000..ed2a109
--- /dev/null
+++ b/tools/testing/selftests/vm/on-fault-limit.c
@@ -0,0 +1,47 @@
+#include <sys/mman.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+
+#ifndef MCL_ONFAULT
+#define MCL_ONFAULT (MCL_FUTURE << 1)
+#endif
+
+static int test_limit(void)
+{
+ int ret = 1;
+ struct rlimit lims;
+ void *map;
+
+ if (getrlimit(RLIMIT_MEMLOCK, &lims)) {
+ perror("getrlimit");
+ return ret;
+ }
+
+ if (mlockall(MCL_ONFAULT)) {
+ perror("mlockall");
+ return ret;
+ }
+
+ map = mmap(NULL, 2 * lims.rlim_max, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS | MAP_POPULATE, 0, 0);
+ if (map != MAP_FAILED)
+ printf("mmap should have failed, but didn't\n");
+ else {
+ ret = 0;
+ munmap(map, 2 * lims.rlim_max);
+ }
+
+ munlockall();
+ return ret;
+}
+
+int main(int argc, char **argv)
+{
+ int ret = 0;
+
+ ret += test_limit();
+ return ret;
+}
diff --git a/tools/testing/selftests/vm/run_vmtests b/tools/testing/selftests/vm/run_vmtests
index c87b681..c1aecce 100755
--- a/tools/testing/selftests/vm/run_vmtests
+++ b/tools/testing/selftests/vm/run_vmtests
@@ -90,4 +90,27 @@ fi
umount $mnt
rm -rf $mnt
echo $nr_hugepgs > /proc/sys/vm/nr_hugepages
+
+echo "--------------------"
+echo "running lock-on-fault"
+echo "--------------------"
+./lock-on-fault
+if [ $? -ne 0 ]; then
+ echo "[FAIL]"
+ exitcode=1
+else
+ echo "[PASS]"
+fi
+
+echo "--------------------"
+echo "running on-fault-limit"
+echo "--------------------"
+sudo -u nobody ./on-fault-limit
+if [ $? -ne 0 ]; then
+ echo "[FAIL]"
+ exitcode=1
+else
+ echo "[PASS]"
+fi
+
exit $exitcode
--
1.9.1
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