Change read_file(), write_file(), read_num() and write_num() in vm_util.c
to report failures to callers instead of exiting from the helper.

Update the helpers to print TAP compatible diagnostics before returning
errors and update their callers to handle those errors. This prepares
the helpers to be moved to tools/lib/mm without carrying selftest-specific
process-exit behaviour into the shared implementation.

Also, make read_file() return a negative errno on failure instead of 0, so
callers can distinguish a successful read from an I/O error. Make
read_num() reject negative and malformed values.

Signed-off-by: Sarthak Sharma <sarthak.sharma@arm.com>
---
 .../testing/selftests/mm/hugepage_settings.c  |  64 +++++++---
 tools/testing/selftests/mm/khugepaged.c       |  13 +-
 .../selftests/mm/split_huge_page_test.c       |   4 +-
 tools/testing/selftests/mm/vm_util.c          | 115 +++++++++++++-----
 tools/testing/selftests/mm/vm_util.h          |   6 +-
 5 files changed, 150 insertions(+), 52 deletions(-)

diff --git a/tools/testing/selftests/mm/hugepage_settings.c b/tools/testing/selftests/mm/hugepage_settings.c
index 2eab2110ac6a..202c8e6b0246 100644
--- a/tools/testing/selftests/mm/hugepage_settings.c
+++ b/tools/testing/selftests/mm/hugepage_settings.c
@@ -61,10 +61,9 @@ int thp_read_string(const char *name, const char * const strings[])
 		exit(EXIT_FAILURE);
 	}
 
-	if (!read_file(path, buf, sizeof(buf))) {
-		perror(path);
+	ret = read_file(path, buf, sizeof(buf));
+	if (ret < 0)
 		exit(EXIT_FAILURE);
-	}
 
 	c = strchr(buf, '[');
 	if (!c) {
@@ -103,12 +102,15 @@ void thp_write_string(const char *name, const char *val)
 		printf("%s: Pathname is too long\n", __func__);
 		exit(EXIT_FAILURE);
 	}
-	write_file(path, val, strlen(val) + 1);
+	ret = write_file(path, val, strlen(val) + 1);
+	if (ret < 0)
+		exit(EXIT_FAILURE);
 }
 
 unsigned long thp_read_num(const char *name)
 {
 	char path[PATH_MAX];
+	unsigned long num;
 	int ret;
 
 	ret = snprintf(path, PATH_MAX, THP_SYSFS "%s", name);
@@ -116,7 +118,11 @@ unsigned long thp_read_num(const char *name)
 		printf("%s: Pathname is too long\n", __func__);
 		exit(EXIT_FAILURE);
 	}
-	return read_num(path);
+	ret = read_num(path, &num);
+	if (ret < 0)
+		exit(EXIT_FAILURE);
+
+	return num;
 }
 
 void thp_write_num(const char *name, unsigned long num)
@@ -129,7 +135,9 @@ void thp_write_num(const char *name, unsigned long num)
 		printf("%s: Pathname is too long\n", __func__);
 		exit(EXIT_FAILURE);
 	}
-	write_num(path, num);
+	ret = write_num(path, num);
+	if (ret < 0)
+		exit(EXIT_FAILURE);
 }
 
 void thp_read_settings(struct thp_settings *settings)
@@ -157,8 +165,13 @@ void thp_read_settings(struct thp_settings *settings)
 		.max_ptes_shared = thp_read_num("khugepaged/max_ptes_shared"),
 		.pages_to_scan = thp_read_num("khugepaged/pages_to_scan"),
 	};
-	if (dev_queue_read_ahead_path[0])
-		settings->read_ahead_kb = read_num(dev_queue_read_ahead_path);
+	if (dev_queue_read_ahead_path[0]) {
+		int ret = read_num(dev_queue_read_ahead_path,
+				   &settings->read_ahead_kb);
+
+		if (ret < 0)
+			exit(EXIT_FAILURE);
+	}
 
 	for (i = 0; i < NR_ORDERS; i++) {
 		if (!((1 << i) & orders)) {
@@ -208,8 +221,13 @@ void thp_write_settings(struct thp_settings *settings)
 	thp_write_num("khugepaged/max_ptes_shared", khugepaged->max_ptes_shared);
 	thp_write_num("khugepaged/pages_to_scan", khugepaged->pages_to_scan);
 
-	if (dev_queue_read_ahead_path[0])
-		write_num(dev_queue_read_ahead_path, settings->read_ahead_kb);
+	if (dev_queue_read_ahead_path[0]) {
+		int ret = write_num(dev_queue_read_ahead_path,
+				    settings->read_ahead_kb);
+
+		if (ret < 0)
+			exit(EXIT_FAILURE);
+	}
 
 	for (i = 0; i < NR_ORDERS; i++) {
 		if (!((1 << i) & orders))
@@ -306,8 +324,11 @@ static unsigned long __thp_supported_orders(bool is_shmem)
 			exit(EXIT_FAILURE);
 		}
 
+		if (access(path, F_OK))
+			continue;
+
 		ret = read_file(path, buf, sizeof(buf));
-		if (ret)
+		if (ret > 0)
 			orders |= 1UL << i;
 	}
 
@@ -425,28 +446,43 @@ static void hugetlb_sysfs_path(char *buf, size_t buflen,
 unsigned long hugetlb_nr_pages(unsigned long size)
 {
 	char path[PATH_MAX];
+	unsigned long nr;
+	int ret;
 
 	hugetlb_sysfs_path(path, sizeof(path), size, "nr_hugepages");
 
-	return read_num(path);
+	ret = read_num(path, &nr);
+	if (ret < 0)
+		exit(EXIT_FAILURE);
+
+	return nr;
 }
 
 void hugetlb_set_nr_pages(unsigned long size, unsigned long nr)
 {
 	char path[PATH_MAX];
+	int ret;
 
 	hugetlb_sysfs_path(path, sizeof(path), size, "nr_hugepages");
 
-	write_num(path, nr);
+	ret = write_num(path, nr);
+	if (ret < 0)
+		exit(EXIT_FAILURE);
 }
 
 unsigned long hugetlb_free_pages(unsigned long size)
 {
 	char path[PATH_MAX];
+	unsigned long nr;
+	int ret;
 
 	hugetlb_sysfs_path(path, sizeof(path), size, "free_hugepages");
 
-	return read_num(path);
+	ret = read_num(path, &nr);
+	if (ret < 0)
+		exit(EXIT_FAILURE);
+
+	return nr;
 }
 
 static bool __hugetlb_setup(unsigned long size, unsigned long nr)
diff --git a/tools/testing/selftests/mm/khugepaged.c b/tools/testing/selftests/mm/khugepaged.c
index 10e8dedcb087..5eac27dd9683 100644
--- a/tools/testing/selftests/mm/khugepaged.c
+++ b/tools/testing/selftests/mm/khugepaged.c
@@ -119,6 +119,7 @@ static void get_finfo(const char *dir)
 	char buf[1 << 10];
 	char path[PATH_MAX];
 	char *str, *end;
+	int ret;
 
 	finfo.dir = dir;
 	stat(finfo.dir, &path_stat);
@@ -138,8 +139,9 @@ static void get_finfo(const char *dir)
 		     major(path_stat.st_dev), minor(path_stat.st_dev))
 	    >= sizeof(path))
 		ksft_exit_fail_msg("%s: Pathname is too long\n", __func__);
-	if (read_file(path, buf, sizeof(buf)) < 0)
-		ksft_exit_fail_perror("read_file(read_num)");
+	ret = read_file(path, buf, sizeof(buf));
+	if (ret < 0)
+		ksft_exit_fail();
 	if (strstr(buf, "DEVTYPE=disk")) {
 		/* Found it */
 		if (snprintf(finfo.dev_queue_read_ahead_path,
@@ -319,7 +321,7 @@ static void *file_setup_area_common(int nr_hpages, enum file_setup_ops setup)
 {
 	const int open_opt = setup == FILE_SETUP_READ_ONLY_FS ? O_RDONLY : O_RDWR;
 	const int mmap_prot = setup == FILE_SETUP_READ_ONLY_FS ? PROT_READ : (PROT_READ | PROT_WRITE);
-	int fd;
+	int fd, ret;
 	void *p;
 	unsigned long size;
 
@@ -363,7 +365,10 @@ static void *file_setup_area_common(int nr_hpages, enum file_setup_ops setup)
 		ksft_exit_fail_perror("mmap()");
 
 	/* Drop page cache */
-	write_file("/proc/sys/vm/drop_caches", "3", 2);
+	ret = write_file("/proc/sys/vm/drop_caches", "3", 2);
+	if (ret)
+		ksft_exit_fail();
+
 	success("OK");
 	return p;
 }
diff --git a/tools/testing/selftests/mm/split_huge_page_test.c b/tools/testing/selftests/mm/split_huge_page_test.c
index 32b991472f74..83a75001518b 100644
--- a/tools/testing/selftests/mm/split_huge_page_test.c
+++ b/tools/testing/selftests/mm/split_huge_page_test.c
@@ -269,7 +269,9 @@ static void write_debugfs(const char *fmt, ...)
 	if (ret >= INPUT_MAX)
 		ksft_exit_fail_msg("%s: Debugfs input is too long\n", __func__);
 
-	write_file(SPLIT_DEBUGFS, input, ret + 1);
+	ret = write_file(SPLIT_DEBUGFS, input, ret + 1);
+	if (ret)
+		ksft_exit_fail();
 }
 
 static char *allocate_zero_filled_hugepage(size_t len)
diff --git a/tools/testing/selftests/mm/vm_util.c b/tools/testing/selftests/mm/vm_util.c
index 311fc5b4513e..bfe0efbe517e 100644
--- a/tools/testing/selftests/mm/vm_util.c
+++ b/tools/testing/selftests/mm/vm_util.c
@@ -704,87 +704,142 @@ int read_file(const char *path, char *buf, size_t buflen)
 	ssize_t numread;
 
 	fd = open(path, O_RDONLY);
-	if (fd == -1)
-		return 0;
+	if (fd == -1) {
+		int err = errno;
+
+		printf("# %s: %s (%d)\n", path, strerror(err), err);
+		return -err;
+	}
 
 	numread = read(fd, buf, buflen - 1);
 	if (numread < 1) {
+		int err = numread ? errno : ENODATA;
 		close(fd);
-		return 0;
+		printf("# %s: %s (%d)\n", path, strerror(err), err);
+		return -err;
 	}
 
 	buf[numread] = '\0';
 	close(fd);
 
-	return (unsigned int) numread;
+	return (int)numread;
 }
 
-void write_file(const char *path, const char *buf, size_t buflen)
+int write_file(const char *path, const char *buf, size_t buflen)
 {
 	int fd, saved_errno;
 	ssize_t numwritten;
 
-	if (buflen < 2)
-		ksft_exit_fail_msg("Incorrect buffer len: %zu\n", buflen);
+	if (buflen < 2) {
+		printf("# %s: %s (%d)\n", path, strerror(EINVAL), EINVAL);
+		return -EINVAL;
+	}
 
 	fd = open(path, O_WRONLY);
-	if (fd == -1)
-		ksft_exit_fail_msg("%s open failed: %s\n", path, strerror(errno));
+	if (fd == -1) {
+		int err = errno;
+
+		printf("# %s: %s (%d)\n", path, strerror(err), err);
+		return -err;
+	}
 
 	numwritten = write(fd, buf, buflen - 1);
 	saved_errno = errno;
 	close(fd);
-	errno = saved_errno;
-	if (numwritten < 0)
-		ksft_exit_fail_msg("%s write(%.*s) failed: %s\n", path, (int)(buflen - 1),
-				buf, strerror(errno));
-	if (numwritten != buflen - 1)
-		ksft_exit_fail_msg("%s write(%.*s) is truncated, expected %zu bytes, got %zd bytes\n",
-				path, (int)(buflen - 1), buf, buflen - 1, numwritten);
+	if (numwritten < 0) {
+		printf("# %s: %s (%d)\n", path, strerror(saved_errno), saved_errno);
+		return -saved_errno;
+	}
+
+	if (numwritten != (ssize_t)(buflen - 1)) {
+		printf("# %s write(%.*s) is truncated, expected %zu bytes, got %zd bytes\n",
+		       path, (int)(buflen - 1), buf, buflen - 1, numwritten);
+		return -EIO;
+	}
+
+	return 0;
 }
 
-unsigned long read_num(const char *path)
+int read_num(const char *path, unsigned long *num)
 {
+	unsigned long val;
+	int err, ret;
 	char buf[21];
+	char *end;
 
-	if (read_file(path, buf, sizeof(buf)) < 0)
-		ksft_exit_fail_perror("read_file()");
+	if (!num)
+		return -EINVAL;
 
-	return strtoul(buf, NULL, 10);
+	ret = read_file(path, buf, sizeof(buf));
+	if (ret < 0)
+		return ret;
+
+	errno = 0;
+	val = strtoul(buf, &end, 10);
+	if (errno) {
+		err = errno;
+		printf("# %s: %s (%d)\n", path, strerror(err), err);
+		return -err;
+	}
+
+	if (end == buf || buf[0] == '-') {
+		printf("# %s: invalid numeric value\n", path);
+		return -EINVAL;
+	}
+
+	if (*end == '\n')
+		end++;
+
+	if (*end != '\0') {
+		printf("# %s: invalid numeric value\n", path);
+		return -EINVAL;
+	}
+
+	*num = val;
+	return 0;
 }
 
-void write_num(const char *path, unsigned long num)
+int write_num(const char *path, unsigned long num)
 {
 	char buf[21];
 
 	sprintf(buf, "%lu", num);
-	write_file(path, buf, strlen(buf) + 1);
+	return write_file(path, buf, strlen(buf) + 1);
 }
 
 static unsigned long shmall, shmmax;
 
 void __shm_limits_restore(void)
 {
-	if (shmmax)
-		write_num("/proc/sys/kernel/shmmax", shmmax);
-	if (shmall)
-		write_num("/proc/sys/kernel/shmall", shmall);
+	if (shmmax && write_num("/proc/sys/kernel/shmmax", shmmax))
+		ksft_exit_fail();
+	if (shmall && write_num("/proc/sys/kernel/shmall", shmall))
+		ksft_exit_fail();
 }
 
 void shm_limits_prepare(unsigned long length)
 {
 	unsigned long nr = length / psize();
 	unsigned long val;
+	int ret;
 
-	val = read_num("/proc/sys/kernel/shmmax");
+	ret = read_num("/proc/sys/kernel/shmmax", &val);
+	if (ret)
+		ksft_exit_fail();
 	if (val < length) {
-		write_num("/proc/sys/kernel/shmmax", length);
+		ret = write_num("/proc/sys/kernel/shmmax", length);
+		if (ret)
+			ksft_exit_fail();
 		shmmax = val;
 	}
 
-	val = read_num("/proc/sys/kernel/shmall");
+	ret = read_num("/proc/sys/kernel/shmall", &val);
+	if (ret)
+		ksft_exit_fail();
 	if (val < nr) {
-		write_num("/proc/sys/kernel/shmall", nr);
+		ret = write_num("/proc/sys/kernel/shmall", nr);
+		if (ret)
+			ksft_exit_fail();
 		shmall = val;
 	}
 }
diff --git a/tools/testing/selftests/mm/vm_util.h b/tools/testing/selftests/mm/vm_util.h
index ea8fc8fdf0eb..28c3d7c1faed 100644
--- a/tools/testing/selftests/mm/vm_util.h
+++ b/tools/testing/selftests/mm/vm_util.h
@@ -164,10 +164,10 @@ int unpoison_memory(unsigned long pfn);
 #define PAGEMAP_PRESENT(ent)	(((ent) & (1ull << 63)) != 0)
 #define PAGEMAP_PFN(ent)	((ent) & ((1ull << 55) - 1))
 
-void write_file(const char *path, const char *buf, size_t buflen);
 int read_file(const char *path, char *buf, size_t buflen);
-unsigned long read_num(const char *path);
-void write_num(const char *path, unsigned long num);
+int write_file(const char *path, const char *buf, size_t buflen);
+int read_num(const char *path, unsigned long *num);
+int write_num(const char *path, unsigned long num);
 
 void shm_limits_prepare(unsigned long length);
 void __shm_limits_restore(void);
-- 
2.39.5


Move read_file(), write_file(), read_num(), and write_num() out of
tools/testing/selftests/mm/vm_util.c into a new shared helper under
tools/lib/mm/.

These helpers are used by mm selftests today and will also be needed by
shared hugepage helpers in subsequent patches. Move them to a generic
location so they can be reused outside selftests as well.

Keep the helpers exposed to mm selftests through vm_util.h by including
the new shared header there, and link the new helper into the
selftests/mm build.

Update the explicit x86 protection_keys 32-bit and 64-bit build rules
to preserve prerequisite paths, now that file_utils.c is built from
tools/lib/mm.

Add tools/lib/mm/ to the MEMORY MANAGEMENT - MISC entry in MAINTAINERS.

Signed-off-by: Sarthak Sharma <sarthak.sharma@arm.com>
---
 MAINTAINERS                          |   1 +
 tools/lib/mm/file_utils.c            | 119 +++++++++++++++++++++++++++
 tools/lib/mm/file_utils.h            |  12 +++
 tools/testing/selftests/mm/Makefile  |  11 +--
 tools/testing/selftests/mm/vm_util.c | 109 ------------------------
 tools/testing/selftests/mm/vm_util.h |   6 +-
 6 files changed, 139 insertions(+), 119 deletions(-)
 create mode 100644 tools/lib/mm/file_utils.c
 create mode 100644 tools/lib/mm/file_utils.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 806bd2d80d15..26b06d80ab45 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17128,6 +17128,7 @@ F:	mm/memory-tiers.c
 F:	mm/page_idle.c
 F:	mm/pgalloc-track.h
 F:	mm/process_vm_access.c
+F:	tools/lib/mm/
 F:	tools/testing/selftests/mm/
 
 MEMORY MANAGEMENT - NUMA MEMBLOCKS AND NUMA EMULATION
diff --git a/tools/lib/mm/file_utils.c b/tools/lib/mm/file_utils.c
new file mode 100644
index 000000000000..792f4b4db625
--- /dev/null
+++ b/tools/lib/mm/file_utils.c
@@ -0,0 +1,119 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "file_utils.h"
+
+int read_file(const char *path, char *buf, size_t buflen)
+{
+	int fd;
+	ssize_t numread;
+
+	fd = open(path, O_RDONLY);
+	if (fd == -1) {
+		int err = errno;
+
+		printf("# %s: %s (%d)\n", path, strerror(err), err);
+		return -err;
+	}
+
+	numread = read(fd, buf, buflen - 1);
+	if (numread < 1) {
+		int err = numread ? errno : ENODATA;
+
+		close(fd);
+		printf("# %s: %s (%d)\n", path, strerror(err), err);
+		return -err;
+	}
+
+	buf[numread] = '\0';
+	close(fd);
+
+	return (int)numread;
+}
+
+int write_file(const char *path, const char *buf, size_t buflen)
+{
+	int fd, saved_errno;
+	ssize_t numwritten;
+
+	if (buflen < 2) {
+		printf("# %s: %s (%d)\n", path, strerror(EINVAL), EINVAL);
+		return -EINVAL;
+	}
+
+	fd = open(path, O_WRONLY);
+	if (fd == -1) {
+		int err = errno;
+
+		printf("# %s: %s (%d)\n", path, strerror(err), err);
+		return -err;
+	}
+
+	numwritten = write(fd, buf, buflen - 1);
+	saved_errno = errno;
+	close(fd);
+	if (numwritten < 0) {
+		printf("# %s: %s (%d)\n", path, strerror(saved_errno),
+		       saved_errno);
+		return -saved_errno;
+	}
+	if (numwritten != (ssize_t)(buflen - 1)) {
+		printf("# %s write(%.*s) is truncated, expected %zu bytes, got %zd bytes\n",
+		       path, (int)(buflen - 1), buf, buflen - 1, numwritten);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+int read_num(const char *path, unsigned long *num)
+{
+	unsigned long val;
+	int err, ret;
+	char buf[21];
+	char *end;
+
+	if (!num)
+		return -EINVAL;
+
+	ret = read_file(path, buf, sizeof(buf));
+	if (ret < 0)
+		return ret;
+
+	errno = 0;
+	val = strtoul(buf, &end, 10);
+	if (errno) {
+		err = errno;
+		printf("# %s: %s (%d)\n", path, strerror(err), err);
+		return -err;
+	}
+
+	if (end == buf || buf[0] == '-') {
+		printf("# %s: invalid numeric value\n", path);
+		return -EINVAL;
+	}
+
+	if (*end == '\n')
+		end++;
+
+	if (*end != '\0') {
+		printf("# %s: invalid numeric value\n", path);
+		return -EINVAL;
+	}
+
+	*num = val;
+	return 0;
+}
+
+int write_num(const char *path, unsigned long num)
+{
+	char buf[21];
+
+	snprintf(buf, sizeof(buf), "%lu", num);
+	return write_file(path, buf, strlen(buf) + 1);
+}
diff --git a/tools/lib/mm/file_utils.h b/tools/lib/mm/file_utils.h
new file mode 100644
index 000000000000..38576790a342
--- /dev/null
+++ b/tools/lib/mm/file_utils.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __MM_FILE_UTILS_H__
+#define __MM_FILE_UTILS_H__
+
+#include <stddef.h>
+
+int read_file(const char *path, char *buf, size_t buflen);
+int write_file(const char *path, const char *buf, size_t buflen);
+int read_num(const char *path, unsigned long *num);
+int write_num(const char *path, unsigned long num);
+
+#endif
diff --git a/tools/testing/selftests/mm/Makefile b/tools/testing/selftests/mm/Makefile
index e6df968f0971..70d6a9ccf9c9 100644
--- a/tools/testing/selftests/mm/Makefile
+++ b/tools/testing/selftests/mm/Makefile
@@ -37,7 +37,8 @@ endif
 # LDLIBS.
 MAKEFLAGS += --no-builtin-rules
 
-CFLAGS = -Wall -O2 -I $(top_srcdir) $(EXTRA_CFLAGS) $(KHDR_INCLUDES) $(TOOLS_INCLUDES)
+CFLAGS = -Wall -O2 -I $(top_srcdir) -I $(top_srcdir)/tools/lib
+CFLAGS += $(EXTRA_CFLAGS) $(KHDR_INCLUDES) $(TOOLS_INCLUDES)
 CFLAGS += -Wunreachable-code
 LDLIBS = -lrt -lpthread -lm
 
@@ -187,8 +188,8 @@ TEST_FILES += write_hugetlb_memory.sh
 
 include ../lib.mk
 
-$(TEST_GEN_PROGS): vm_util.c hugepage_settings.c
-$(TEST_GEN_FILES): vm_util.c hugepage_settings.c
+$(TEST_GEN_PROGS): vm_util.c hugepage_settings.c $(top_srcdir)/tools/lib/mm/file_utils.c
+$(TEST_GEN_FILES): vm_util.c hugepage_settings.c $(top_srcdir)/tools/lib/mm/file_utils.c
 
 $(OUTPUT)/uffd-stress: uffd-common.c
 $(OUTPUT)/uffd-unit-tests: uffd-common.c
@@ -217,7 +218,7 @@ $(BINARIES_32): CFLAGS += -m32 -mxsave
 $(BINARIES_32): LDLIBS += -lrt -ldl -lm
 $(BINARIES_32): $(OUTPUT)/%_32: %.c
 	$(call msg,CC,,$@)
-	$(Q)$(CC) $(CFLAGS) $(EXTRA_CFLAGS) $(notdir $^) $(LDLIBS) -o $@
+	$(Q)$(CC) $(CFLAGS) $(EXTRA_CFLAGS) $^ $(LDLIBS) -o $@
 $(foreach t,$(VMTARGETS),$(eval $(call gen-target-rule-32,$(t))))
 endif
 
@@ -226,7 +227,7 @@ $(BINARIES_64): CFLAGS += -m64 -mxsave
 $(BINARIES_64): LDLIBS += -lrt -ldl
 $(BINARIES_64): $(OUTPUT)/%_64: %.c
 	$(call msg,CC,,$@)
-	$(Q)$(CC) $(CFLAGS) $(EXTRA_CFLAGS) $(notdir $^) $(LDLIBS) -o $@
+	$(Q)$(CC) $(CFLAGS) $(EXTRA_CFLAGS) $^ $(LDLIBS) -o $@
 $(foreach t,$(VMTARGETS),$(eval $(call gen-target-rule-64,$(t))))
 endif
 
diff --git a/tools/testing/selftests/mm/vm_util.c b/tools/testing/selftests/mm/vm_util.c
index bfe0efbe517e..f276eee57680 100644
--- a/tools/testing/selftests/mm/vm_util.c
+++ b/tools/testing/selftests/mm/vm_util.c
@@ -698,115 +698,6 @@ int unpoison_memory(unsigned long pfn)
 	return ret > 0 ? 0 : -errno;
 }
 
-int read_file(const char *path, char *buf, size_t buflen)
-{
-	int fd;
-	ssize_t numread;
-
-	fd = open(path, O_RDONLY);
-	if (fd == -1) {
-		int err = errno;
-
-		printf("# %s: %s (%d)\n", path, strerror(err), err);
-		return -err;
-	}
-
-	numread = read(fd, buf, buflen - 1);
-	if (numread < 1) {
-		int err = numread ? errno : ENODATA;
-		close(fd);
-		printf("# %s: %s (%d)\n", path, strerror(err), err);
-		return -err;
-	}
-
-	buf[numread] = '\0';
-	close(fd);
-
-	return (int)numread;
-}
-
-int write_file(const char *path, const char *buf, size_t buflen)
-{
-	int fd, saved_errno;
-	ssize_t numwritten;
-
-	if (buflen < 2) {
-		printf("# %s: %s (%d)\n", path, strerror(EINVAL), EINVAL);
-		return -EINVAL;
-	}
-
-	fd = open(path, O_WRONLY);
-	if (fd == -1) {
-		int err = errno;
-
-		printf("# %s: %s (%d)\n", path, strerror(err), err);
-		return -err;
-	}
-
-	numwritten = write(fd, buf, buflen - 1);
-	saved_errno = errno;
-	close(fd);
-	if (numwritten < 0) {
-		printf("# %s: %s (%d)\n", path, strerror(saved_errno), saved_errno);
-		return -saved_errno;
-	}
-
-	if (numwritten != (ssize_t)(buflen - 1)) {
-		printf("# %s write(%.*s) is truncated, expected %zu bytes, got %zd bytes\n",
-		       path, (int)(buflen - 1), buf, buflen - 1, numwritten);
-		return -EIO;
-	}
-
-	return 0;
-}
-
-int read_num(const char *path, unsigned long *num)
-{
-	unsigned long val;
-	int err, ret;
-	char buf[21];
-	char *end;
-
-	if (!num)
-		return -EINVAL;
-
-	ret = read_file(path, buf, sizeof(buf));
-	if (ret < 0)
-		return ret;
-
-	errno = 0;
-	val = strtoul(buf, &end, 10);
-	if (errno) {
-		err = errno;
-		printf("# %s: %s (%d)\n", path, strerror(err), err);
-		return -err;
-	}
-
-	if (end == buf || buf[0] == '-') {
-		printf("# %s: invalid numeric value\n", path);
-		return -EINVAL;
-	}
-
-	if (*end == '\n')
-		end++;
-
-	if (*end != '\0') {
-		printf("# %s: invalid numeric value\n", path);
-		return -EINVAL;
-	}
-
-	*num = val;
-	return 0;
-}
-
-int write_num(const char *path, unsigned long num)
-{
-	char buf[21];
-
-	sprintf(buf, "%lu", num);
-	return write_file(path, buf, strlen(buf) + 1);
-}
-
 static unsigned long shmall, shmmax;
 
 void __shm_limits_restore(void)
diff --git a/tools/testing/selftests/mm/vm_util.h b/tools/testing/selftests/mm/vm_util.h
index 28c3d7c1faed..d45135283732 100644
--- a/tools/testing/selftests/mm/vm_util.h
+++ b/tools/testing/selftests/mm/vm_util.h
@@ -8,6 +8,7 @@
 #include <unistd.h> /* _SC_PAGESIZE */
 #include "kselftest.h"
 #include <linux/fs.h>
+#include <mm/file_utils.h>
 
 #define BIT_ULL(nr)                   (1ULL << (nr))
 #define PM_SOFT_DIRTY                 BIT_ULL(55)
@@ -164,11 +165,6 @@ int unpoison_memory(unsigned long pfn);
 #define PAGEMAP_PRESENT(ent)	(((ent) & (1ull << 63)) != 0)
 #define PAGEMAP_PFN(ent)	((ent) & ((1ull << 55) - 1))
 
-int read_file(const char *path, char *buf, size_t buflen);
-int write_file(const char *path, const char *buf, size_t buflen);
-int read_num(const char *path, unsigned long *num);
-int write_num(const char *path, unsigned long num);
-
 void shm_limits_prepare(unsigned long length);
 void __shm_limits_restore(void);
 
-- 
2.39.5


Move hugepage_settings.[ch] from tools/testing/selftests/mm/ to
tools/lib/mm/ so the THP and HugeTLB helpers can be shared more easily
between selftests and other tools.

Keep the helpers exposed to mm selftests through vm_util.h where possible,
and use direct <mm/hugepage_settings.h> includes for users that do not
include vm_util.h. Adjust the selftests/mm build to compile the moved
implementation from its new location.

Remove the remaining kselftest dependency from hugepage_settings.c by
replacing ksft_print_msg() calls with TAP comment style printf()
diagnostics.

Signed-off-by: Sarthak Sharma <sarthak.sharma@arm.com>
---
 .../selftests => lib}/mm/hugepage_settings.c    | 17 ++++++++++++-----
 .../selftests => lib}/mm/hugepage_settings.h    |  0
 tools/testing/selftests/mm/Makefile             |  6 ++++--
 tools/testing/selftests/mm/compaction_test.c    |  2 +-
 tools/testing/selftests/mm/cow.c                |  1 -
 .../selftests/mm/folio_split_race_test.c        |  1 -
 tools/testing/selftests/mm/guard-regions.c      |  1 -
 tools/testing/selftests/mm/gup_longterm.c       |  1 -
 tools/testing/selftests/mm/gup_test.c           |  1 -
 tools/testing/selftests/mm/hmm-tests.c          |  6 +++---
 tools/testing/selftests/mm/hugetlb-madvise.c    |  1 -
 tools/testing/selftests/mm/hugetlb-mmap.c       |  1 -
 tools/testing/selftests/mm/hugetlb-mremap.c     |  1 -
 tools/testing/selftests/mm/hugetlb-shm.c        |  1 -
 .../testing/selftests/mm/hugetlb-soft-offline.c |  2 +-
 tools/testing/selftests/mm/hugetlb-vmemmap.c    |  1 -
 tools/testing/selftests/mm/hugetlb_dio.c        |  1 -
 .../selftests/mm/hugetlb_fault_after_madv.c     |  1 -
 .../testing/selftests/mm/hugetlb_madv_vs_map.c  |  1 -
 tools/testing/selftests/mm/khugepaged.c         |  1 -
 tools/testing/selftests/mm/ksm_tests.c          |  1 -
 tools/testing/selftests/mm/migration.c          |  5 ++---
 tools/testing/selftests/mm/pagemap_ioctl.c      |  1 -
 tools/testing/selftests/mm/prctl_thp_disable.c  |  1 -
 tools/testing/selftests/mm/protection_keys.c    |  2 +-
 tools/testing/selftests/mm/soft-dirty.c         |  1 -
 .../testing/selftests/mm/split_huge_page_test.c |  1 -
 tools/testing/selftests/mm/thuge-gen.c          |  1 -
 tools/testing/selftests/mm/transhuge-stress.c   |  1 -
 tools/testing/selftests/mm/uffd-common.h        |  1 -
 tools/testing/selftests/mm/uffd-wp-mremap.c     |  2 +-
 .../testing/selftests/mm/va_high_addr_switch.c  |  1 -
 tools/testing/selftests/mm/vm_util.h            |  1 +
 33 files changed, 26 insertions(+), 40 deletions(-)
 rename tools/{testing/selftests => lib}/mm/hugepage_settings.c (97%)
 rename tools/{testing/selftests => lib}/mm/hugepage_settings.h (100%)

diff --git a/tools/testing/selftests/mm/hugepage_settings.c b/tools/lib/mm/hugepage_settings.c
similarity index 97%
rename from tools/testing/selftests/mm/hugepage_settings.c
rename to tools/lib/mm/hugepage_settings.c
index 202c8e6b0246..8d9e44727edb 100644
--- a/tools/testing/selftests/mm/hugepage_settings.c
+++ b/tools/lib/mm/hugepage_settings.c
@@ -9,11 +9,16 @@
 #include <string.h>
 #include <unistd.h>
 
-#include "vm_util.h"
+#include "file_utils.h"
 #include "hugepage_settings.h"
 
 #define THP_SYSFS "/sys/kernel/mm/transparent_hugepage/"
 #define MAX_SETTINGS_DEPTH 4
+
+#ifndef ARRAY_SIZE
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
+#endif
+
 static struct thp_settings settings_stack[MAX_SETTINGS_DEPTH];
 static int settings_index;
 static struct thp_settings saved_settings;
@@ -403,8 +408,7 @@ int detect_hugetlb_page_sizes(unsigned long sizes[], int max)
 		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);
+		printf("# [INFO] detected hugetlb page size: %zu KiB\n", kb);
 	}
 	closedir(dir);
 	return count;
@@ -538,7 +542,8 @@ unsigned long hugetlb_setup(unsigned long nr, unsigned long sizes[],
 		return 0;
 
 	if (nr_enabled > max) {
-		ksft_print_msg("detected %d huge page sizes, will only test %d\n", nr_enabled, max);
+		printf("# detected %d huge page sizes, will only test %d\n",
+		       nr_enabled, max);
 		nr_enabled = max;
 	}
 
@@ -610,8 +615,10 @@ static void hugepage_restore_settings_atexit(void)
 
 static void hugepage_restore_settings_sighandler(int sig)
 {
+	(void)sig;
+
 	/* exit() will invoke the hugepage_restore_settings_atexit handler. */
-	exit(KSFT_FAIL);
+	exit(EXIT_FAILURE);
 }
 
 void hugepage_save_settings(bool thp, bool hugetlb)
diff --git a/tools/testing/selftests/mm/hugepage_settings.h b/tools/lib/mm/hugepage_settings.h
similarity index 100%
rename from tools/testing/selftests/mm/hugepage_settings.h
rename to tools/lib/mm/hugepage_settings.h
diff --git a/tools/testing/selftests/mm/Makefile b/tools/testing/selftests/mm/Makefile
index 70d6a9ccf9c9..e77c4cc41b47 100644
--- a/tools/testing/selftests/mm/Makefile
+++ b/tools/testing/selftests/mm/Makefile
@@ -188,8 +188,10 @@ TEST_FILES += write_hugetlb_memory.sh
 
 include ../lib.mk
 
-$(TEST_GEN_PROGS): vm_util.c hugepage_settings.c $(top_srcdir)/tools/lib/mm/file_utils.c
-$(TEST_GEN_FILES): vm_util.c hugepage_settings.c $(top_srcdir)/tools/lib/mm/file_utils.c
+$(TEST_GEN_PROGS): vm_util.c $(top_srcdir)/tools/lib/mm/hugepage_settings.c \
+		   $(top_srcdir)/tools/lib/mm/file_utils.c
+$(TEST_GEN_FILES): vm_util.c $(top_srcdir)/tools/lib/mm/hugepage_settings.c \
+		   $(top_srcdir)/tools/lib/mm/file_utils.c
 
 $(OUTPUT)/uffd-stress: uffd-common.c
 $(OUTPUT)/uffd-unit-tests: uffd-common.c
diff --git a/tools/testing/selftests/mm/compaction_test.c b/tools/testing/selftests/mm/compaction_test.c
index 5b582588e015..b2eaa490e7c2 100644
--- a/tools/testing/selftests/mm/compaction_test.c
+++ b/tools/testing/selftests/mm/compaction_test.c
@@ -15,9 +15,9 @@
 #include <errno.h>
 #include <unistd.h>
 #include <string.h>
+#include <mm/hugepage_settings.h>
 
 #include "kselftest.h"
-#include "hugepage_settings.h"
 
 #define MAP_SIZE_MB	100
 #define MAP_SIZE	(MAP_SIZE_MB * 1024 * 1024)
diff --git a/tools/testing/selftests/mm/cow.c b/tools/testing/selftests/mm/cow.c
index 0c627ea89ff7..3c3d129c91b2 100644
--- a/tools/testing/selftests/mm/cow.c
+++ b/tools/testing/selftests/mm/cow.c
@@ -29,7 +29,6 @@
 #include "../../../../mm/gup_test.h"
 #include "kselftest.h"
 #include "vm_util.h"
-#include "hugepage_settings.h"
 
 static size_t pagesize;
 static int pagemap_fd;
diff --git a/tools/testing/selftests/mm/folio_split_race_test.c b/tools/testing/selftests/mm/folio_split_race_test.c
index 6329e37fff4c..496b74b37476 100644
--- a/tools/testing/selftests/mm/folio_split_race_test.c
+++ b/tools/testing/selftests/mm/folio_split_race_test.c
@@ -25,7 +25,6 @@
 #include <unistd.h>
 #include "vm_util.h"
 #include "kselftest.h"
-#include "hugepage_settings.h"
 
 uint64_t page_size;
 uint64_t pmd_pagesize;
diff --git a/tools/testing/selftests/mm/guard-regions.c b/tools/testing/selftests/mm/guard-regions.c
index b21df3040b1c..ed967b3c7f37 100644
--- a/tools/testing/selftests/mm/guard-regions.c
+++ b/tools/testing/selftests/mm/guard-regions.c
@@ -21,7 +21,6 @@
 #include <sys/uio.h>
 #include <unistd.h>
 #include "vm_util.h"
-#include "hugepage_settings.h"
 
 #include "../pidfd/pidfd.h"
 
diff --git a/tools/testing/selftests/mm/gup_longterm.c b/tools/testing/selftests/mm/gup_longterm.c
index eb8963e9d98f..68c840bae082 100644
--- a/tools/testing/selftests/mm/gup_longterm.c
+++ b/tools/testing/selftests/mm/gup_longterm.c
@@ -29,7 +29,6 @@
 #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/gup_test.c b/tools/testing/selftests/mm/gup_test.c
index 3f841a96f870..5f44761dbec0 100644
--- a/tools/testing/selftests/mm/gup_test.c
+++ b/tools/testing/selftests/mm/gup_test.c
@@ -14,7 +14,6 @@
 #include <mm/gup_test.h>
 #include "kselftest.h"
 #include "vm_util.h"
-#include "hugepage_settings.h"
 
 #define MB (1UL << 20)
 
diff --git a/tools/testing/selftests/mm/hmm-tests.c b/tools/testing/selftests/mm/hmm-tests.c
index 2f2b9879d100..e1bb031019f2 100644
--- a/tools/testing/selftests/mm/hmm-tests.c
+++ b/tools/testing/selftests/mm/hmm-tests.c
@@ -10,9 +10,6 @@
  * bugs.
  */
 
-#include "kselftest_harness.h"
-#include "hugepage_settings.h"
-
 #include <errno.h>
 #include <fcntl.h>
 #include <stdio.h>
@@ -29,6 +26,9 @@
 #include <sys/mman.h>
 #include <sys/ioctl.h>
 #include <sys/time.h>
+#include <mm/hugepage_settings.h>
+
+#include "kselftest_harness.h"
 
 /*
  * This is a private UAPI to the kernel test module so it isn't exported
diff --git a/tools/testing/selftests/mm/hugetlb-madvise.c b/tools/testing/selftests/mm/hugetlb-madvise.c
index 555b4b3d1430..57cf790ca478 100644
--- a/tools/testing/selftests/mm/hugetlb-madvise.c
+++ b/tools/testing/selftests/mm/hugetlb-madvise.c
@@ -14,7 +14,6 @@
 #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 0f2aad1b7dbd..a458becf5832 100644
--- a/tools/testing/selftests/mm/hugetlb-mmap.c
+++ b/tools/testing/selftests/mm/hugetlb-mmap.c
@@ -18,7 +18,6 @@
 #include <linux/memfd.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-mremap.c b/tools/testing/selftests/mm/hugetlb-mremap.c
index ed3d92e862d8..9b724af66e93 100644
--- a/tools/testing/selftests/mm/hugetlb-mremap.c
+++ b/tools/testing/selftests/mm/hugetlb-mremap.c
@@ -26,7 +26,6 @@
 #include <stdbool.h>
 #include "kselftest.h"
 #include "vm_util.h"
-#include "hugepage_settings.h"
 
 #define DEFAULT_LENGTH_MB 10UL
 #define MB_TO_BYTES(x) (x * 1024 * 1024)
diff --git a/tools/testing/selftests/mm/hugetlb-shm.c b/tools/testing/selftests/mm/hugetlb-shm.c
index 3ff7f062b7eb..f4514da49e1d 100644
--- a/tools/testing/selftests/mm/hugetlb-shm.c
+++ b/tools/testing/selftests/mm/hugetlb-shm.c
@@ -29,7 +29,6 @@
 #include <sys/mman.h>
 
 #include "vm_util.h"
-#include "hugepage_settings.h"
 
 #define LENGTH (256UL*1024*1024)
 
diff --git a/tools/testing/selftests/mm/hugetlb-soft-offline.c b/tools/testing/selftests/mm/hugetlb-soft-offline.c
index bc202e4ed2bd..20864e7d4e0c 100644
--- a/tools/testing/selftests/mm/hugetlb-soft-offline.c
+++ b/tools/testing/selftests/mm/hugetlb-soft-offline.c
@@ -21,9 +21,9 @@
 #include <sys/mman.h>
 #include <sys/statfs.h>
 #include <sys/types.h>
+#include <mm/hugepage_settings.h>
 
 #include "kselftest.h"
-#include "hugepage_settings.h"
 
 #ifndef MADV_SOFT_OFFLINE
 #define MADV_SOFT_OFFLINE 101
diff --git a/tools/testing/selftests/mm/hugetlb-vmemmap.c b/tools/testing/selftests/mm/hugetlb-vmemmap.c
index 507df78a158d..c46a656c25a0 100644
--- a/tools/testing/selftests/mm/hugetlb-vmemmap.c
+++ b/tools/testing/selftests/mm/hugetlb-vmemmap.c
@@ -11,7 +11,6 @@
 #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 fb4600570e13..9495974eccbe 100644
--- a/tools/testing/selftests/mm/hugetlb_dio.c
+++ b/tools/testing/selftests/mm/hugetlb_dio.c
@@ -20,7 +20,6 @@
 #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 2dc158054f66..56c5a8533e9d 100644
--- a/tools/testing/selftests/mm/hugetlb_fault_after_madv.c
+++ b/tools/testing/selftests/mm/hugetlb_fault_after_madv.c
@@ -10,7 +10,6 @@
 
 #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 f94549efcc6f..2532a42b98df 100644
--- a/tools/testing/selftests/mm/hugetlb_madv_vs_map.c
+++ b/tools/testing/selftests/mm/hugetlb_madv_vs_map.c
@@ -25,7 +25,6 @@
 #include <unistd.h>
 
 #include "vm_util.h"
-#include "hugepage_settings.h"
 
 #define INLOOP_ITER 100
 
diff --git a/tools/testing/selftests/mm/khugepaged.c b/tools/testing/selftests/mm/khugepaged.c
index 5eac27dd9683..2382973b2f55 100644
--- a/tools/testing/selftests/mm/khugepaged.c
+++ b/tools/testing/selftests/mm/khugepaged.c
@@ -22,7 +22,6 @@
 #include "linux/magic.h"
 
 #include "vm_util.h"
-#include "hugepage_settings.h"
 
 #define BASE_ADDR ((void *)(1UL << 30))
 static unsigned long hpage_pmd_size;
diff --git a/tools/testing/selftests/mm/ksm_tests.c b/tools/testing/selftests/mm/ksm_tests.c
index a050f4840cfa..cc37492cf32c 100644
--- a/tools/testing/selftests/mm/ksm_tests.c
+++ b/tools/testing/selftests/mm/ksm_tests.c
@@ -15,7 +15,6 @@
 #include "kselftest.h"
 #include <include/vdso/time64.h>
 #include "vm_util.h"
-#include "hugepage_settings.h"
 
 #define KSM_SYSFS_PATH "/sys/kernel/mm/ksm/"
 #define KSM_FP(s) (KSM_SYSFS_PATH s)
diff --git a/tools/testing/selftests/mm/migration.c b/tools/testing/selftests/mm/migration.c
index 29f7492453d4..4fe97c033261 100644
--- a/tools/testing/selftests/mm/migration.c
+++ b/tools/testing/selftests/mm/migration.c
@@ -4,9 +4,6 @@
  * paths in the kernel.
  */
 
-#include "kselftest_harness.h"
-#include "hugepage_settings.h"
-
 #include <strings.h>
 #include <pthread.h>
 #include <numa.h>
@@ -16,6 +13,8 @@
 #include <sys/types.h>
 #include <signal.h>
 #include <time.h>
+
+#include "kselftest_harness.h"
 #include "vm_util.h"
 
 #define TWOMEG		(2<<20)
diff --git a/tools/testing/selftests/mm/pagemap_ioctl.c b/tools/testing/selftests/mm/pagemap_ioctl.c
index 6f8971d5b3ce..804372803080 100644
--- a/tools/testing/selftests/mm/pagemap_ioctl.c
+++ b/tools/testing/selftests/mm/pagemap_ioctl.c
@@ -23,7 +23,6 @@
 
 #include "vm_util.h"
 #include "kselftest.h"
-#include "hugepage_settings.h"
 
 #define PAGEMAP_BITS_ALL		(PAGE_IS_WPALLOWED | PAGE_IS_WRITTEN |	\
 					 PAGE_IS_FILE | PAGE_IS_PRESENT |	\
diff --git a/tools/testing/selftests/mm/prctl_thp_disable.c b/tools/testing/selftests/mm/prctl_thp_disable.c
index d8d9d1de57b8..a4f8451791cb 100644
--- a/tools/testing/selftests/mm/prctl_thp_disable.c
+++ b/tools/testing/selftests/mm/prctl_thp_disable.c
@@ -14,7 +14,6 @@
 #include <sys/wait.h>
 
 #include "kselftest_harness.h"
-#include "hugepage_settings.h"
 #include "vm_util.h"
 
 #ifndef PR_THP_DISABLE_EXCEPT_ADVISED
diff --git a/tools/testing/selftests/mm/protection_keys.c b/tools/testing/selftests/mm/protection_keys.c
index 9a6d954ee371..5ba2033e8a09 100644
--- a/tools/testing/selftests/mm/protection_keys.c
+++ b/tools/testing/selftests/mm/protection_keys.c
@@ -45,8 +45,8 @@
 #include <unistd.h>
 #include <sys/ptrace.h>
 #include <setjmp.h>
+#include <mm/hugepage_settings.h>
 
-#include "hugepage_settings.h"
 #include "pkey-helpers.h"
 
 int iteration_nr = 1;
diff --git a/tools/testing/selftests/mm/soft-dirty.c b/tools/testing/selftests/mm/soft-dirty.c
index fb1864a68e1c..6c22ac9e93db 100644
--- a/tools/testing/selftests/mm/soft-dirty.c
+++ b/tools/testing/selftests/mm/soft-dirty.c
@@ -9,7 +9,6 @@
 
 #include "kselftest.h"
 #include "vm_util.h"
-#include "hugepage_settings.h"
 
 #define PAGEMAP_FILE_PATH "/proc/self/pagemap"
 #define TEST_ITERATIONS 10000
diff --git a/tools/testing/selftests/mm/split_huge_page_test.c b/tools/testing/selftests/mm/split_huge_page_test.c
index 83a75001518b..e744c9434e7d 100644
--- a/tools/testing/selftests/mm/split_huge_page_test.c
+++ b/tools/testing/selftests/mm/split_huge_page_test.c
@@ -21,7 +21,6 @@
 #include <time.h>
 #include "vm_util.h"
 #include "kselftest.h"
-#include "hugepage_settings.h"
 
 uint64_t pagesize;
 unsigned int pageshift;
diff --git a/tools/testing/selftests/mm/thuge-gen.c b/tools/testing/selftests/mm/thuge-gen.c
index 22b9c2f1c35d..0da15d530a1f 100644
--- a/tools/testing/selftests/mm/thuge-gen.c
+++ b/tools/testing/selftests/mm/thuge-gen.c
@@ -14,7 +14,6 @@
 #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/transhuge-stress.c b/tools/testing/selftests/mm/transhuge-stress.c
index 8eb0c5630e7e..96f72898ebe0 100644
--- a/tools/testing/selftests/mm/transhuge-stress.c
+++ b/tools/testing/selftests/mm/transhuge-stress.c
@@ -17,7 +17,6 @@
 #include <sys/mman.h>
 #include "vm_util.h"
 #include "kselftest.h"
-#include "hugepage_settings.h"
 
 int backing_fd = -1;
 int mmap_flags = MAP_ANONYMOUS | MAP_NORESERVE | MAP_PRIVATE;
diff --git a/tools/testing/selftests/mm/uffd-common.h b/tools/testing/selftests/mm/uffd-common.h
index 92a21b97f745..0723843a7626 100644
--- a/tools/testing/selftests/mm/uffd-common.h
+++ b/tools/testing/selftests/mm/uffd-common.h
@@ -37,7 +37,6 @@
 
 #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/uffd-wp-mremap.c b/tools/testing/selftests/mm/uffd-wp-mremap.c
index c973d6722720..eb4b2433b00e 100644
--- a/tools/testing/selftests/mm/uffd-wp-mremap.c
+++ b/tools/testing/selftests/mm/uffd-wp-mremap.c
@@ -7,8 +7,8 @@
 #include <assert.h>
 #include <linux/mman.h>
 #include <sys/mman.h>
+#include <mm/hugepage_settings.h>
 #include "kselftest.h"
-#include "hugepage_settings.h"
 #include "uffd-common.h"
 
 static int pagemap_fd;
diff --git a/tools/testing/selftests/mm/va_high_addr_switch.c b/tools/testing/selftests/mm/va_high_addr_switch.c
index e24d7ba00b44..5a354a664d1f 100644
--- a/tools/testing/selftests/mm/va_high_addr_switch.c
+++ b/tools/testing/selftests/mm/va_high_addr_switch.c
@@ -11,7 +11,6 @@
 
 #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.h b/tools/testing/selftests/mm/vm_util.h
index d45135283732..aa856f0d32d6 100644
--- a/tools/testing/selftests/mm/vm_util.h
+++ b/tools/testing/selftests/mm/vm_util.h
@@ -9,6 +9,7 @@
 #include "kselftest.h"
 #include <linux/fs.h>
 #include <mm/file_utils.h>
+#include <mm/hugepage_settings.h>
 
 #define BIT_ULL(nr)                   (1ULL << (nr))
 #define PM_SOFT_DIRTY                 BIT_ULL(55)
-- 
2.39.5


Add a command-line tool for benchmarking get_user_pages fast-path
(GUP_FAST), pin_user_pages fast-path (PIN_FAST), and pin_user_pages
longterm (PIN_LONGTERM) via the CONFIG_GUP_TEST debugfs interface.

When invoked without arguments, gup_bench runs the benchmark subset
of configurations covered by run_gup_matrix() in run_vmtests.sh: all
three GUP commands across read/write, private/shared mappings, and a
range of page counts, with THP on/off for regular mappings and hugetlb
for huge page mappings. Restore HugeTLB settings after each hugetlb
benchmark run. Validate numeric command-line arguments instead of
relying on atoi().

This tool is a mix of reused and new logic. The mapping/setup path comes
from selftests/mm/gup_test.c, while the default benchmark matrix matches
the benchmark subset of run_gup_matrix() in run_vmtests.sh. The standalone
CLI and tools/mm integration are added here and the HugeTLB setup code is
shared via tools/lib/mm.

Add gup_bench to BUILD_TARGETS and INSTALL_TARGETS in tools/mm/Makefile,
link it against the shared tools/lib/mm hugepage helpers, and ignore the
resulting binary in tools/mm/.gitignore. While here, also add the
missing thp_swap_allocator_test entry to .gitignore.

Add tools/mm/gup_bench.c to the GUP entry in MAINTAINERS.

Suggested-by: David Hildenbrand (Arm) <david@kernel.org>
Signed-off-by: Sarthak Sharma <sarthak.sharma@arm.com>
---
 MAINTAINERS          |   1 +
 tools/mm/.gitignore  |   2 +
 tools/mm/Makefile    |  10 +-
 tools/mm/gup_bench.c | 482 +++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 492 insertions(+), 3 deletions(-)
 create mode 100644 tools/mm/gup_bench.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 26b06d80ab45..7d121dee9f0f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17024,6 +17024,7 @@ T:	git git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
 F:	mm/gup.c
 F:	mm/gup_test.c
 F:	mm/gup_test.h
+F:	tools/mm/gup_bench.c
 F:	tools/testing/selftests/mm/gup_longterm.c
 F:	tools/testing/selftests/mm/gup_test.c
 
diff --git a/tools/mm/.gitignore b/tools/mm/.gitignore
index 922879f93fc8..154d740be02e 100644
--- a/tools/mm/.gitignore
+++ b/tools/mm/.gitignore
@@ -2,3 +2,5 @@
 slabinfo
 page-types
 page_owner_sort
+thp_swap_allocator_test
+gup_bench
diff --git a/tools/mm/Makefile b/tools/mm/Makefile
index f5725b5c23aa..d82cc8c43ee0 100644
--- a/tools/mm/Makefile
+++ b/tools/mm/Makefile
@@ -3,13 +3,14 @@
 #
 include ../scripts/Makefile.include
 
-BUILD_TARGETS=page-types slabinfo page_owner_sort thp_swap_allocator_test
+BUILD_TARGETS=page-types slabinfo page_owner_sort thp_swap_allocator_test gup_bench
 INSTALL_TARGETS = $(BUILD_TARGETS) thpmaps
 
 LIB_DIR = ../lib/api
 LIBS = $(LIB_DIR)/libapi.a
+GUP_BENCH_OBJS = gup_bench.c ../lib/mm/hugepage_settings.c ../lib/mm/file_utils.c
 
-CFLAGS += -Wall -Wextra -I../lib/ -pthread
+CFLAGS += -Wall -Wextra -I../lib/ -I../.. -pthread
 LDFLAGS += $(LIBS) -pthread
 
 all: $(BUILD_TARGETS)
@@ -22,8 +23,11 @@ $(LIBS):
 %: %.c
 	$(CC) $(CFLAGS) -o $@ $< $(LDFLAGS)
 
+gup_bench: $(GUP_BENCH_OBJS) $(LIBS)
+	$(CC) $(CFLAGS) -o $@ $(GUP_BENCH_OBJS) $(LDFLAGS)
+
 clean:
-	$(RM) page-types slabinfo page_owner_sort thp_swap_allocator_test
+	$(RM) page-types slabinfo page_owner_sort thp_swap_allocator_test gup_bench
 	make -C $(LIB_DIR) clean
 
 sbindir ?= /usr/sbin
diff --git a/tools/mm/gup_bench.c b/tools/mm/gup_bench.c
new file mode 100644
index 000000000000..497b8f3f6ac4
--- /dev/null
+++ b/tools/mm/gup_bench.c
@@ -0,0 +1,482 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Microbenchmark for get_user_pages (GUP) kernel interfaces.
+ *
+ * Exercises GUP_FAST_BENCHMARK, PIN_FAST_BENCHMARK, and
+ * PIN_LONGTERM_BENCHMARK via the CONFIG_GUP_TEST debugfs interface.
+ *
+ * Example use:
+ *   # Run the full matrix (all commands, access modes, page counts):
+ *   ./gup_bench
+ *
+ *   # Single run: pin_user_pages_fast, 512 pages, write access, hugetlb:
+ *   ./gup_bench -a -n 512 -w -H
+ *
+ * Requires CONFIG_GUP_TEST=y and debugfs mounted at /sys/kernel/debug.
+ * Must be run as root.
+ */
+
+#define __SANE_USERSPACE_TYPES__ // Use ll64
+#include <fcntl.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <pthread.h>
+#include <stdbool.h>
+#include <stdatomic.h>
+#include <stdint.h>
+#include <limits.h>
+#include <string.h>
+#include <mm/gup_test.h>
+#include <mm/hugepage_settings.h>
+
+#define MB (1UL << 20)
+
+#ifndef ARRAY_SIZE
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
+#endif
+
+/* Just the flags we need, copied from the kernel internals. */
+#define FOLL_WRITE	0x01	/* check pte is writable */
+
+#define GUP_TEST_FILE "/sys/kernel/debug/gup_test"
+
+static unsigned int psize(void)
+{
+	static unsigned int __page_size;
+
+	if (!__page_size)
+		__page_size = sysconf(_SC_PAGESIZE);
+	return __page_size;
+}
+
+static unsigned long cmd;
+static const char *bench_label;
+static int gup_fd, repeats = 1;
+static unsigned long size = 128 * MB;
+static atomic_int bench_error;
+/* Serialize prints */
+static pthread_mutex_t print_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+static const unsigned long bench_cmds[] = {
+	GUP_FAST_BENCHMARK,
+	PIN_FAST_BENCHMARK,
+	PIN_LONGTERM_BENCHMARK,
+};
+
+static const int bench_thp_modes[] = { 1, 0 };	/* on, off */
+static const int bench_nr_pages_list[] = { 1, 512, 123, -1 };
+
+static const char *cmd_to_str(unsigned long cmd)
+{
+	switch (cmd) {
+	case GUP_FAST_BENCHMARK:
+		return "GUP_FAST_BENCHMARK";
+	case PIN_FAST_BENCHMARK:
+		return "PIN_FAST_BENCHMARK";
+	case PIN_LONGTERM_BENCHMARK:
+		return "PIN_LONGTERM_BENCHMARK";
+	}
+	return "Unknown command";
+}
+
+static long parse_long_arg_base(const char *arg, const char *name, int base)
+{
+	char *end;
+	long val;
+
+	errno = 0;
+	val = strtol(arg, &end, base);
+	if (errno || end == arg || *end != '\0') {
+		fprintf(stderr, "Invalid %s '%s'\n", name, arg);
+		exit(1);
+	}
+	return val;
+}
+
+static long parse_long_arg(const char *arg, const char *name)
+{
+	return parse_long_arg_base(arg, name, 10);
+}
+
+static long parse_positive_long_arg(const char *arg, const char *name)
+{
+	long val = parse_long_arg(arg, name);
+
+	if (val < 1) {
+		fprintf(stderr, "Invalid %s '%s'\n", name, arg);
+		exit(1);
+	}
+
+	return val;
+}
+
+struct bench_run {
+	unsigned long cmd;
+	int thp;		/* -1: default, 0: off, 1: on */
+	bool hugetlb;
+	bool write;		/* whether to set FOLL_WRITE */
+	bool shared;
+	int nr_pages;		/* -1 means all pages (size / psize()) */
+	unsigned long size;
+	char *file;
+	int nthreads;
+	unsigned int gup_flags;
+};
+
+void *gup_thread(void *data)
+{
+	struct gup_test gup = *(struct gup_test *)data;
+	int i, status;
+
+	for (i = 0; i < repeats; i++) {
+		gup.size = size;
+		status = ioctl(gup_fd, cmd, &gup);
+		if (status) {
+			bench_error = 1;
+			break;
+		}
+
+		pthread_mutex_lock(&print_mutex);
+		printf("%s time: get:%lld put:%lld us",
+		       bench_label, gup.get_delta_usec,
+		       gup.put_delta_usec);
+		if (gup.size != size)
+			printf(", truncated (size: %lld)", gup.size);
+		printf("\n");
+		pthread_mutex_unlock(&print_mutex);
+	}
+
+	return NULL;
+}
+
+static int run_bench(struct bench_run *run)
+{
+	struct gup_test gup = { 0 };
+	int zero_fd, i, ret, started_threads = 0;
+	unsigned long nr_pages_per_call;
+	int flags = MAP_PRIVATE;
+	pthread_t *tid;
+	char label[128];
+	char *p;
+	bool restore_hugetlb = false;
+
+	/* Set globals consumed by gup_thread */
+	cmd = run->cmd;
+	size = run->size;
+	bench_error = 0;
+
+	if (run->hugetlb) {
+		unsigned long hp_size = default_huge_page_size();
+
+		if (!hp_size) {
+			fprintf(stderr, "Could not determine huge page size\n");
+			return 1;
+		}
+
+		if (size > ULONG_MAX - (hp_size - 1)) {
+			fprintf(stderr, "HugeTLB mapping size is too large\n");
+			return 1;
+		}
+
+		size = (size + hp_size - 1) & ~(hp_size - 1);
+		if (!hugetlb_setup_default(size / hp_size)) {
+			fprintf(stderr, "Not enough huge pages\n");
+			hugetlb_restore_settings();
+			return 1;
+		}
+		restore_hugetlb = true;
+		flags |= (MAP_HUGETLB | MAP_ANONYMOUS);
+	}
+
+	if (run->shared) {
+		flags &= ~MAP_PRIVATE;
+		flags |= MAP_SHARED;
+	}
+
+	nr_pages_per_call = run->nr_pages < 0 ? size / psize() :
+		(unsigned long)run->nr_pages;
+
+	if (nr_pages_per_call > UINT_MAX) {
+		fprintf(stderr, "Page count is too large\n");
+		if (restore_hugetlb)
+			hugetlb_restore_settings();
+		return 1;
+	}
+	gup.nr_pages_per_call = nr_pages_per_call;
+
+	gup.gup_flags = run->gup_flags;
+	if (run->write)
+		gup.gup_flags |= FOLL_WRITE;
+
+	snprintf(label, sizeof(label), "%s (nr_pages=%-4u %s %s %s %s)",
+		 cmd_to_str(run->cmd),
+		 gup.nr_pages_per_call,
+		 run->write  ? "write"   : "read",
+		 run->shared ? "shared"  : "private",
+		 run->hugetlb ? "hugetlb=on" : "hugetlb=off",
+		 run->hugetlb ? "thp=off" :
+		 (run->thp == 1 ? "thp=on" :
+		 (run->thp == 0 ? "thp=off" : "thp=default")));
+	bench_label = label;
+
+	zero_fd = open(run->file, O_RDWR);
+	if (zero_fd < 0) {
+		fprintf(stderr, "Unable to open %s: %s\n", run->file, strerror(errno));
+		if (restore_hugetlb)
+			hugetlb_restore_settings();
+		return 1;
+	}
+
+	p = mmap(NULL, size, PROT_READ | PROT_WRITE, flags, zero_fd, 0);
+	close(zero_fd);
+	if (p == MAP_FAILED) {
+		fprintf(stderr, "mmap: %s\n", strerror(errno));
+		if (restore_hugetlb)
+			hugetlb_restore_settings();
+		return 1;
+	}
+	gup.addr = (unsigned long)p;
+
+	if (run->thp == 1)
+		madvise(p, size, MADV_HUGEPAGE);
+	else if (run->thp == 0)
+		madvise(p, size, MADV_NOHUGEPAGE);
+
+	/* Fault them in here, from user space. */
+	for (; (unsigned long)p < gup.addr + size; p += psize())
+		p[0] = 0;
+
+	tid = malloc(sizeof(pthread_t) * run->nthreads);
+	if (!tid) {
+		fprintf(stderr, "Failed to allocate %d threads: %s\n",
+			run->nthreads, strerror(errno));
+		munmap((void *)gup.addr, size);
+		if (restore_hugetlb)
+			hugetlb_restore_settings();
+		return 1;
+	}
+
+	for (i = 0; i < run->nthreads; i++) {
+		ret = pthread_create(&tid[i], NULL, gup_thread, &gup);
+		if (ret) {
+			fprintf(stderr, "pthread_create failed: %s\n", strerror(ret));
+			bench_error = 1;
+			break;
+		}
+		started_threads++;
+	}
+	for (i = 0; i < started_threads; i++) {
+		ret = pthread_join(tid[i], NULL);
+		if (ret) {
+			fprintf(stderr, "pthread_join failed: %s\n", strerror(ret));
+			bench_error = 1;
+		}
+	}
+
+	free(tid);
+	munmap((void *)gup.addr, size);
+	if (restore_hugetlb)
+		hugetlb_restore_settings();
+
+	return bench_error ? 1 : 0;
+}
+
+static int run_matrix(void)
+{
+	unsigned int c, t, w, s, n;
+	int ret = 0;
+
+	for (c = 0; c < ARRAY_SIZE(bench_cmds); c++) {
+		for (w = 0; w <= 1; w++) {
+			for (s = 0; s <= 1; s++) {
+				for (t = 0; t < ARRAY_SIZE(bench_thp_modes); t++) {
+					for (n = 0; n < ARRAY_SIZE(bench_nr_pages_list); n++) {
+						struct bench_run run = {
+							.cmd	  = bench_cmds[c],
+							.thp	  = bench_thp_modes[t],
+							.hugetlb  = false,
+							.write	  = w,
+							.shared	  = s,
+							.nr_pages = bench_nr_pages_list[n],
+							.size	  = 128 * MB,
+							.file	  = "/dev/zero",
+							.nthreads = 1,
+						};
+						ret |= run_bench(&run);
+					}
+				}
+				/* hugetlb: 256M to match run_gup_matrix() in run_vmtests.sh */
+				for (n = 0; n < ARRAY_SIZE(bench_nr_pages_list); n++) {
+					struct bench_run run = {
+						.cmd	  = bench_cmds[c],
+						.thp	  = -1,
+						.hugetlb  = true,
+						.write	  = w,
+						.shared	  = s,
+						.nr_pages = bench_nr_pages_list[n],
+						.size	  = 256 * MB,
+						.file	  = "/dev/zero",
+						.nthreads = 1,
+					};
+					ret |= run_bench(&run);
+				}
+			}
+		}
+	}
+	return ret;
+}
+
+int main(int argc, char **argv)
+{
+	struct bench_run run = {
+		.cmd	  = GUP_FAST_BENCHMARK,
+		.thp	  = -1,
+		.hugetlb  = false,
+		.write	  = true,
+		.shared	  = false,
+		.nr_pages = 1,
+		.size	  = 128 * MB,
+		.file	  = "/dev/zero",
+		.nthreads = 1,
+	};
+	int opt, result;
+
+	while ((opt = getopt(argc, argv, "m:r:n:F:f:aj:tTLuwWSH")) != -1) {
+		switch (opt) {
+		/* Command selection */
+		case 'u':
+			run.cmd = GUP_FAST_BENCHMARK;
+			break;
+		case 'a':
+			run.cmd = PIN_FAST_BENCHMARK;
+			break;
+		case 'L':
+			run.cmd = PIN_LONGTERM_BENCHMARK;
+			break;
+
+		/* Memory type */
+		case 'H':
+			run.hugetlb = true;
+			break;
+		case 't':
+			run.thp = 1;
+			break;
+		case 'T':
+			run.thp = 0;
+			break;
+
+		/* Access mode */
+		case 'w':
+			run.write = true;
+			break;
+		case 'W':
+			run.write = false;
+			break;
+		case 'S':
+			run.shared = true;
+			break;
+
+		/* Mapping */
+		case 'f':
+			run.file = optarg;
+			break;
+
+		/* Sizing and iteration */
+		case 'm':
+			run.size = parse_positive_long_arg(optarg, "size");
+			if (run.size > ULONG_MAX / MB) {
+				fprintf(stderr, "Invalid size '%s'\n", optarg);
+				exit(1);
+			}
+			run.size *= MB;
+			break;
+		case 'n': {
+			long val;
+
+			val = parse_long_arg(optarg, "page count");
+			if (val != -1 && (val < 1 || val > INT_MAX)) {
+				fprintf(stderr, "Invalid page count '%s'\n", optarg);
+				exit(1);
+			}
+			run.nr_pages = val;
+			break;
+		}
+		case 'r': {
+			long val;
+
+			val = parse_positive_long_arg(optarg, "repeat count");
+			if (val > INT_MAX) {
+				fprintf(stderr, "Invalid repeat count '%s'\n", optarg);
+				exit(1);
+			}
+			repeats = val;
+			break;
+		}
+		case 'j': {
+			long val;
+
+			val = parse_positive_long_arg(optarg, "thread count");
+			if (val > INT_MAX ||
+			    (size_t)val > SIZE_MAX / sizeof(pthread_t)) {
+				fprintf(stderr, "Invalid thread count '%s'\n", optarg);
+				exit(1);
+			}
+			run.nthreads = val;
+			break;
+		}
+
+		/* Advanced */
+		case 'F': {
+			long val;
+
+			val = parse_long_arg_base(optarg, "GUP flags", 0);
+			if (val < 0 || val > UINT_MAX) {
+				fprintf(stderr, "Invalid GUP flags '%s'\n", optarg);
+				exit(1);
+			}
+
+			run.gup_flags = val;
+			break;
+		}
+
+		default:
+			fprintf(stderr, "Wrong argument\n");
+			exit(1);
+		}
+	}
+
+	if (optind != argc) {
+		fprintf(stderr, "Unexpected argument '%s'\n", argv[optind]);
+		exit(1);
+	}
+
+	gup_fd = open(GUP_TEST_FILE, O_RDWR);
+	if (gup_fd == -1) {
+		if (errno == EACCES) {
+			fprintf(stderr, "Please run as root\n");
+		} else if (errno == ENOENT) {
+			DIR *debugfs = opendir("/sys/kernel/debug");
+
+			if (!debugfs) {
+				fprintf(stderr, "Mount debugfs at /sys/kernel/debug\n");
+			} else {
+				closedir(debugfs);
+				fprintf(stderr, "Check CONFIG_GUP_TEST in kernel config\n");
+			}
+		} else {
+			fprintf(stderr, "Failed to open %s: %s\n", GUP_TEST_FILE,
+				strerror(errno));
+		}
+		exit(1);
+	}
+
+	result = (argc == 1) ? run_matrix() : run_bench(&run);
+	close(gup_fd);
+	return result;
+}
-- 
2.39.5


Rewrite gup_test.c using kselftest_harness.h. The new test covers 12
mapping configurations: THP on, THP off and hugetlb, each across
private/shared and read/write variants. It runs seven test cases per
variant: get_user_pages, get_user_pages_fast, pin_user_pages,
pin_user_pages_fast, pin_user_pages_longterm, and DUMP_USER_PAGES_TEST
via both get and pin.

Each test case sweeps four nr_pages_per_call values: 1, 512, 123, and
all pages. This preserves the old run_gup_matrix() sweep: 12 mapping
combinations x 5 GUP/PUP operations x 4 batch sizes = 240 ioctl sweeps.
It also expands DUMP_USER_PAGES_TEST coverage from one standalone
invocation to 12 variants x 2 dump modes x 4 batch sizes = 96
additional sweeps.

Preserve the old sparse dump coverage from run_vmtests.sh with one
standalone test that exercises DUMP_USER_PAGES_TEST with page indices
0, 19 and 0x1000, fetching the full mapping in one ioctl call. This
brings the total to 85 TAP-reported cases (12 x 7 + 1) and 337 ioctl
sweeps (240 + 96 + 1).

On a Radxa Orion O6 board, ./gup_test completes in 5.39s on average
over 10 runs (range: 5.33s - 5.48s).

Update run_vmtests.sh: remove run_gup_matrix() and the multiple flagged
invocations of gup_test, replacing them with a single unconditional
invocation. Benchmark functionality is handled by tools/mm/gup_bench
introduced in the previous patch.

Update Documentation/core-api/pin_user_pages.rst to reflect the new
harness-based gup_test interface rather than command-line flag
invocations.

Suggested-by: David Hildenbrand (Arm) <david@kernel.org>
Signed-off-by: Sarthak Sharma <sarthak.sharma@arm.com>
---
 Documentation/core-api/pin_user_pages.rst |  12 +-
 tools/testing/selftests/mm/gup_test.c     | 605 ++++++++++++++--------
 tools/testing/selftests/mm/run_vmtests.sh |  37 +-
 3 files changed, 397 insertions(+), 257 deletions(-)

diff --git a/Documentation/core-api/pin_user_pages.rst b/Documentation/core-api/pin_user_pages.rst
index c16ca163b55e..ea722adf22cc 100644
--- a/Documentation/core-api/pin_user_pages.rst
+++ b/Documentation/core-api/pin_user_pages.rst
@@ -230,10 +230,16 @@ This file::
 
  tools/testing/selftests/mm/gup_test.c
 
-has the following new calls to exercise the new pin*() wrapper functions:
+contains the following test cases to exercise pin_user_pages*():
 
-* PIN_FAST_BENCHMARK (./gup_test -a)
-* PIN_BASIC_TEST (./gup_test -b)
+* pin_user_pages via PIN_BASIC_TEST
+* pin_user_pages_fast via PIN_FAST_BENCHMARK
+* pin_user_pages_longterm via PIN_LONGTERM_BENCHMARK
+
+Run with::
+
+  make -C tools/testing/selftests/mm
+  ./tools/testing/selftests/mm/gup_test
 
 You can monitor how many total dma-pinned pages have been acquired and released
 since the system was booted, via two new /proc/vmstat entries: ::
diff --git a/tools/testing/selftests/mm/gup_test.c b/tools/testing/selftests/mm/gup_test.c
index 5f44761dbec0..d9caa9fb8b78 100644
--- a/tools/testing/selftests/mm/gup_test.c
+++ b/tools/testing/selftests/mm/gup_test.c
@@ -1,274 +1,443 @@
 #define __SANE_USERSPACE_TYPES__ // Use ll64
 #include <fcntl.h>
 #include <errno.h>
+#include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <unistd.h>
 #include <dirent.h>
 #include <sys/ioctl.h>
 #include <sys/mman.h>
 #include <sys/stat.h>
 #include <sys/types.h>
-#include <pthread.h>
-#include <assert.h>
 #include <mm/gup_test.h>
 #include "kselftest.h"
 #include "vm_util.h"
+#include "kselftest_harness.h"
 
 #define MB (1UL << 20)
 
+#ifndef ARRAY_SIZE
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
+#endif
+
 /* Just the flags we need, copied from the kernel internals. */
 #define FOLL_WRITE	0x01	/* check pte is writable */
 
+/* Page counts exercising single, THP-batch, partial, and full-mapping GUP. */
+static const int nr_pages_list[] = { 1, 512, 123, -1 };
+
 #define GUP_TEST_FILE "/sys/kernel/debug/gup_test"
 
-static unsigned long cmd = GUP_FAST_BENCHMARK;
-static int gup_fd, repeats = 1;
-static unsigned long size = 128 * MB;
-/* Serialize prints */
-static pthread_mutex_t print_mutex = PTHREAD_MUTEX_INITIALIZER;
+FIXTURE(gup_test)
+{
+	int gup_fd;
+	char *addr;
+	unsigned long size;
+};
+
+FIXTURE_VARIANT(gup_test)
+{
+	bool thp;
+	bool hugetlb;
+	bool write;
+	bool shared;
+};
+
+FIXTURE_VARIANT_ADD(gup_test, private_write)
+{
+	.thp = false,
+	.hugetlb = false,
+	.write = true,
+	.shared = false,
+};
+
+FIXTURE_VARIANT_ADD(gup_test, private_readonly)
+{
+	.thp = false,
+	.hugetlb = false,
+	.write = false,
+	.shared = false,
+};
+
+FIXTURE_VARIANT_ADD(gup_test, private_write_thp)
+{
+	.thp = true,
+	.hugetlb = false,
+	.write = true,
+	.shared = false,
+};
+
+FIXTURE_VARIANT_ADD(gup_test, private_readonly_thp)
+{
+	.thp = true,
+	.hugetlb = false,
+	.write = false,
+	.shared = false,
+};
+
+FIXTURE_VARIANT_ADD(gup_test, private_write_hugetlb)
+{
+	.thp = false,
+	.hugetlb = true,
+	.write = true,
+	.shared = false,
+};
+
+FIXTURE_VARIANT_ADD(gup_test, private_readonly_hugetlb)
+{
+	.thp = false,
+	.hugetlb = true,
+	.write = false,
+	.shared = false,
+};
+
+FIXTURE_VARIANT_ADD(gup_test, shared_write)
+{
+	.thp = false,
+	.hugetlb = false,
+	.write = true,
+	.shared = true,
+};
+
+FIXTURE_VARIANT_ADD(gup_test, shared_readonly)
+{
+	.thp = false,
+	.hugetlb = false,
+	.write = false,
+	.shared = true,
+};
+
+FIXTURE_VARIANT_ADD(gup_test, shared_write_thp)
+{
+	.thp = true,
+	.hugetlb = false,
+	.write = true,
+	.shared = true,
+};
 
-static char *cmd_to_str(unsigned long cmd)
+FIXTURE_VARIANT_ADD(gup_test, shared_readonly_thp)
 {
-	switch (cmd) {
-	case GUP_FAST_BENCHMARK:
-		return "GUP_FAST_BENCHMARK";
-	case PIN_FAST_BENCHMARK:
-		return "PIN_FAST_BENCHMARK";
-	case PIN_LONGTERM_BENCHMARK:
-		return "PIN_LONGTERM_BENCHMARK";
-	case GUP_BASIC_TEST:
-		return "GUP_BASIC_TEST";
-	case PIN_BASIC_TEST:
-		return "PIN_BASIC_TEST";
-	case DUMP_USER_PAGES_TEST:
-		return "DUMP_USER_PAGES_TEST";
+	.thp = true,
+	.hugetlb = false,
+	.write = false,
+	.shared = true,
+};
+
+FIXTURE_VARIANT_ADD(gup_test, shared_write_hugetlb)
+{
+	.thp = false,
+	.hugetlb = true,
+	.write = true,
+	.shared = true,
+};
+
+FIXTURE_VARIANT_ADD(gup_test, shared_readonly_hugetlb)
+{
+	.thp = false,
+	.hugetlb = true,
+	.write = false,
+	.shared = true,
+};
+
+FIXTURE_SETUP(gup_test)
+{
+	int mmap_flags = MAP_PRIVATE;
+	int zero_fd;
+	char *p;
+
+	/* zero_fd has to be >= 0. Already checked in main() */
+	zero_fd = open("/dev/zero", O_RDWR);
+	ASSERT_GE(zero_fd, 0);
+
+	/* gup_fd has to be >= 0. Already checked in main() */
+	self->gup_fd = open(GUP_TEST_FILE, O_RDWR);
+	ASSERT_GE(self->gup_fd, 0);
+
+	self->size = variant->hugetlb ? 256 * MB : 128 * MB;
+
+	/* Check for hugetlb */
+	if (variant->hugetlb) {
+		unsigned long hp_size = default_huge_page_size();
+
+		if (!hp_size) {
+			close(zero_fd);
+			close(self->gup_fd);
+			SKIP(return, "HugeTLB not available\n");
+		}
+
+		self->size = (self->size + hp_size - 1) & ~(hp_size - 1);
+		if (!hugetlb_setup_default(self->size / hp_size)) {
+			hugetlb_restore_settings();
+			close(zero_fd);
+			close(self->gup_fd);
+			SKIP(return, "Not enough huge pages\n");
+		}
+
+		mmap_flags |= (MAP_HUGETLB | MAP_ANONYMOUS);
+	}
+
+	if (variant->shared)
+		mmap_flags = (mmap_flags & ~MAP_PRIVATE) | MAP_SHARED;
+
+	self->addr = mmap(NULL, self->size, PROT_READ | PROT_WRITE,
+			  mmap_flags, zero_fd, 0);
+
+	close(zero_fd);
+
+	ASSERT_NE(self->addr, MAP_FAILED) {
+		int err = errno;
+
+		close(self->gup_fd);
+		if (variant->hugetlb)
+			hugetlb_restore_settings();
+		TH_LOG("mmap failed: %s", strerror(err));
 	}
-	return "Unknown command";
+
+	if (variant->thp)
+		madvise(self->addr, self->size, MADV_HUGEPAGE);
+	else
+		madvise(self->addr, self->size, MADV_NOHUGEPAGE);
+
+	for (p = self->addr; (unsigned long)p < (unsigned long)self->addr
+			+ self->size; p += psize())
+		p[0] = 0;
 }
 
-void *gup_thread(void *data)
+FIXTURE_TEARDOWN(gup_test)
 {
-	struct gup_test gup = *(struct gup_test *)data;
-	int i, status;
-
-	/* Only report timing information on the *_BENCHMARK commands: */
-	if ((cmd == PIN_FAST_BENCHMARK) || (cmd == GUP_FAST_BENCHMARK) ||
-	     (cmd == PIN_LONGTERM_BENCHMARK)) {
-		for (i = 0; i < repeats; i++) {
-			gup.size = size;
-			status = ioctl(gup_fd, cmd, &gup);
-			if (status)
-				break;
-
-			pthread_mutex_lock(&print_mutex);
-			ksft_print_msg("%s: Time: get:%lld put:%lld us",
-				       cmd_to_str(cmd), gup.get_delta_usec,
-				       gup.put_delta_usec);
-			if (gup.size != size)
-				ksft_print_msg(", truncated (size: %lld)", gup.size);
-			ksft_print_msg("\n");
-			pthread_mutex_unlock(&print_mutex);
-		}
-	} else {
-		gup.size = size;
-		status = ioctl(gup_fd, cmd, &gup);
-		if (status)
-			goto return_;
-
-		pthread_mutex_lock(&print_mutex);
-		ksft_print_msg("%s: done\n", cmd_to_str(cmd));
-		if (gup.size != size)
-			ksft_print_msg("Truncated (size: %lld)\n", gup.size);
-		pthread_mutex_unlock(&print_mutex);
+	munmap(self->addr, self->size);
+	close(self->gup_fd);
+
+	if (variant->hugetlb)
+		hugetlb_restore_settings();
+}
+
+TEST_F(gup_test, get_user_pages)
+{
+	/* Tests the get_user_pages path */
+	int i;
+
+	for (i = 0; i < (int)ARRAY_SIZE(nr_pages_list); i++) {
+		struct gup_test gup = { 0 };
+
+		gup.addr = (unsigned long)self->addr;
+		gup.size = self->size;
+		gup.nr_pages_per_call = nr_pages_list[i] < 0 ?
+			self->size / psize() : nr_pages_list[i];
+
+		if (variant->write)
+			gup.gup_flags |= FOLL_WRITE;
+
+		TH_LOG("nr_pages_per_call=%u", gup.nr_pages_per_call);
+		ASSERT_EQ(ioctl(self->gup_fd, GUP_BASIC_TEST, &gup), 0);
+	}
+}
+
+TEST_F(gup_test, pin_user_pages)
+{
+	/* Tests the pin_user_pages path */
+	int i;
+
+	for (i = 0; i < (int)ARRAY_SIZE(nr_pages_list); i++) {
+		struct gup_test gup = { 0 };
+
+		gup.addr = (unsigned long)self->addr;
+		gup.size = self->size;
+		gup.nr_pages_per_call = nr_pages_list[i] < 0 ?
+			self->size / psize() : nr_pages_list[i];
+
+		if (variant->write)
+			gup.gup_flags |= FOLL_WRITE;
+
+		TH_LOG("nr_pages_per_call=%u", gup.nr_pages_per_call);
+		ASSERT_EQ(ioctl(self->gup_fd, PIN_BASIC_TEST, &gup), 0);
 	}
+}
 
-return_:
-	ksft_test_result(!status, "ioctl status %d\n", status);
-	return NULL;
+TEST_F(gup_test, dump_user_pages_with_get)
+{
+	/* Tests DUMP_USER_PAGES_TEST using get_user_pages */
+	int i;
+
+	for (i = 0; i < (int)ARRAY_SIZE(nr_pages_list); i++) {
+		struct gup_test gup = { 0 };
+
+		gup.addr = (unsigned long)self->addr;
+		gup.size = self->size;
+		gup.nr_pages_per_call = nr_pages_list[i] < 0 ?
+			self->size / psize() : nr_pages_list[i];
+
+		if (variant->write)
+			gup.gup_flags |= FOLL_WRITE;
+
+		gup.which_pages[0] = 1;
+
+		TH_LOG("nr_pages_per_call=%u", gup.nr_pages_per_call);
+		ASSERT_EQ(ioctl(self->gup_fd, DUMP_USER_PAGES_TEST, &gup), 0);
+	}
 }
 
-int main(int argc, char **argv)
+TEST_F(gup_test, dump_user_pages_with_pin)
 {
-	struct gup_test gup = { 0 };
-	int filed, i, opt, nr_pages = 1, thp = -1, write = 1, nthreads = 1, ret;
-	int flags = MAP_PRIVATE;
-	char *file = "/dev/zero";
-	bool hugetlb = false;
-	pthread_t *tid;
-	char *p;
+	/* Tests DUMP_USER_PAGES_TEST using pin_user_pages */
+	int i;
 
-	while ((opt = getopt(argc, argv, "m:r:n:F:f:abcj:tTLUuwWSHpz")) != -1) {
-		switch (opt) {
-		case 'a':
-			cmd = PIN_FAST_BENCHMARK;
-			break;
-		case 'b':
-			cmd = PIN_BASIC_TEST;
-			break;
-		case 'L':
-			cmd = PIN_LONGTERM_BENCHMARK;
-			break;
-		case 'c':
-			cmd = DUMP_USER_PAGES_TEST;
-			/*
-			 * Dump page 0 (index 1). May be overridden later, by
-			 * user's non-option arguments.
-			 *
-			 * .which_pages is zero-based, so that zero can mean "do
-			 * nothing".
-			 */
-			gup.which_pages[0] = 1;
-			break;
-		case 'p':
-			/* works only with DUMP_USER_PAGES_TEST */
-			gup.test_flags |= GUP_TEST_FLAG_DUMP_PAGES_USE_PIN;
-			break;
-		case 'F':
-			/* strtol, so you can pass flags in hex form */
-			gup.gup_flags = strtol(optarg, 0, 0);
-			break;
-		case 'j':
-			nthreads = atoi(optarg);
-			break;
-		case 'm':
-			size = atoi(optarg) * MB;
-			break;
-		case 'r':
-			repeats = atoi(optarg);
-			break;
-		case 'n':
-			nr_pages = atoi(optarg);
-			if (nr_pages < 0)
-				nr_pages = size / psize();
-			break;
-		case 't':
-			thp = 1;
-			break;
-		case 'T':
-			thp = 0;
-			break;
-		case 'U':
-			cmd = GUP_BASIC_TEST;
-			break;
-		case 'u':
-			cmd = GUP_FAST_BENCHMARK;
-			break;
-		case 'w':
-			write = 1;
-			break;
-		case 'W':
-			write = 0;
-			break;
-		case 'f':
-			file = optarg;
-			break;
-		case 'S':
-			flags &= ~MAP_PRIVATE;
-			flags |= MAP_SHARED;
-			break;
-		case 'H':
-			flags |= (MAP_HUGETLB | MAP_ANONYMOUS);
-			hugetlb = true;
-			break;
-		default:
-			ksft_exit_fail_msg("Wrong argument\n");
-		}
+	for (i = 0; i < (int)ARRAY_SIZE(nr_pages_list); i++) {
+		struct gup_test gup = { 0 };
+
+		gup.addr = (unsigned long)self->addr;
+		gup.size = self->size;
+		gup.nr_pages_per_call = nr_pages_list[i] < 0 ?
+			self->size / psize() : nr_pages_list[i];
+
+		if (variant->write)
+			gup.gup_flags |= FOLL_WRITE;
+
+		gup.which_pages[0] = 1;
+		gup.test_flags |= GUP_TEST_FLAG_DUMP_PAGES_USE_PIN;
+
+		TH_LOG("nr_pages_per_call=%u", gup.nr_pages_per_call);
+		ASSERT_EQ(ioctl(self->gup_fd, DUMP_USER_PAGES_TEST, &gup), 0);
 	}
+}
 
-	if (optind < argc) {
-		int extra_arg_count = 0;
-		/*
-		 * For example:
-		 *
-		 *   ./gup_test -c 0 1 0x1001
-		 *
-		 * ...to dump pages 0, 1, and 4097
-		 */
-
-		while ((optind < argc) &&
-		       (extra_arg_count < GUP_TEST_MAX_PAGES_TO_DUMP)) {
-			/*
-			 * Do the 1-based indexing here, so that the user can
-			 * use normal 0-based indexing on the command line.
-			 */
-			long page_index = strtol(argv[optind], 0, 0) + 1;
-
-			gup.which_pages[extra_arg_count] = page_index;
-			extra_arg_count++;
-			optind++;
-		}
+TEST_F(gup_test, get_user_pages_fast)
+{
+	/* Tests the lockless get_user_pages_fast() path */
+	int i;
+
+	for (i = 0; i < (int)ARRAY_SIZE(nr_pages_list); i++) {
+		struct gup_test gup = { 0 };
+
+		gup.addr = (unsigned long)self->addr;
+		gup.size = self->size;
+		gup.nr_pages_per_call = nr_pages_list[i] < 0 ?
+			self->size / psize() : nr_pages_list[i];
+
+		if (variant->write)
+			gup.gup_flags |= FOLL_WRITE;
+
+		TH_LOG("nr_pages_per_call=%u", gup.nr_pages_per_call);
+		ASSERT_EQ(ioctl(self->gup_fd, GUP_FAST_BENCHMARK, &gup), 0);
 	}
+}
+
+TEST_F(gup_test, pin_user_pages_fast)
+{
+	/* Tests the lockless pin_user_pages_fast() path */
+	int i;
 
-	ksft_print_header();
+	for (i = 0; i < (int)ARRAY_SIZE(nr_pages_list); i++) {
+		struct gup_test gup = { 0 };
 
-	if (hugetlb) {
-		unsigned long hp_size = default_huge_page_size();
+		gup.addr = (unsigned long)self->addr;
+		gup.size = self->size;
+		gup.nr_pages_per_call = nr_pages_list[i] < 0 ?
+			self->size / psize() : nr_pages_list[i];
 
-		if (!hp_size)
-			ksft_exit_skip("HugeTLB is unavailable\n");
+		if (variant->write)
+			gup.gup_flags |= FOLL_WRITE;
 
-		size = (size + hp_size - 1) & ~(hp_size - 1);
-		if (!hugetlb_setup_default(size / hp_size))
-			ksft_exit_skip("Not enough huge pages\n");
+		TH_LOG("nr_pages_per_call=%u", gup.nr_pages_per_call);
+		ASSERT_EQ(ioctl(self->gup_fd, PIN_FAST_BENCHMARK, &gup), 0);
 	}
+}
 
-	ksft_set_plan(nthreads);
+TEST_F(gup_test, pin_user_pages_longterm)
+{
+	/* Tests pin_user_pages() with FOLL_LONGTERM */
+	int i;
 
-	filed = open(file, O_RDWR|O_CREAT, 0664);
-	if (filed < 0)
-		ksft_exit_fail_msg("Unable to open %s: %s\n", file, strerror(errno));
+	for (i = 0; i < (int)ARRAY_SIZE(nr_pages_list); i++) {
+		struct gup_test gup = { 0 };
 
-	gup.nr_pages_per_call = nr_pages;
-	if (write)
-		gup.gup_flags |= FOLL_WRITE;
+		gup.addr = (unsigned long)self->addr;
+		gup.size = self->size;
+		gup.nr_pages_per_call = nr_pages_list[i] < 0 ?
+			self->size / psize() : nr_pages_list[i];
 
-	gup_fd = open(GUP_TEST_FILE, O_RDWR);
-	if (gup_fd == -1) {
-		switch (errno) {
-		case EACCES:
-			if (getuid())
-				ksft_print_msg("Please run this test as root\n");
-			break;
-		case ENOENT:
-			if (opendir("/sys/kernel/debug") == NULL)
-				ksft_print_msg("mount debugfs at /sys/kernel/debug\n");
-			ksft_print_msg("check if CONFIG_GUP_TEST is enabled in kernel config\n");
-			break;
-		default:
-			ksft_print_msg("failed to open %s: %s\n", GUP_TEST_FILE, strerror(errno));
-			break;
-		}
-		ksft_test_result_skip("Please run this test as root\n");
-		ksft_exit_pass();
+		if (variant->write)
+			gup.gup_flags |= FOLL_WRITE;
+
+		TH_LOG("nr_pages_per_call=%u", gup.nr_pages_per_call);
+		ASSERT_EQ(ioctl(self->gup_fd, PIN_LONGTERM_BENCHMARK, &gup), 0);
 	}
+}
+
+TEST(dump_user_pages_sparse_indices)
+{
+	/* Tests sparse multi-index which_pages[] inputs. */
+	struct gup_test gup = { 0 };
+	unsigned long size = 128 * MB;
+	int zero_fd, gup_fd;
+	char *addr, *p;
+
+	zero_fd = open("/dev/zero", O_RDWR);
+	ASSERT_GE(zero_fd, 0);
 
-	p = mmap(NULL, size, PROT_READ | PROT_WRITE, flags, filed, 0);
-	if (p == MAP_FAILED)
-		ksft_exit_fail_msg("mmap: %s\n", strerror(errno));
-	gup.addr = (unsigned long)p;
+	gup_fd = open(GUP_TEST_FILE, O_RDWR);
+	ASSERT_GE(gup_fd, 0);
+
+	addr = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, zero_fd, 0);
+	close(zero_fd);
+	ASSERT_NE(addr, MAP_FAILED);
 
-	if (thp == 1)
-		madvise(p, size, MADV_HUGEPAGE);
-	else if (thp == 0)
-		madvise(p, size, MADV_NOHUGEPAGE);
+	madvise(addr, size, MADV_HUGEPAGE);
 
-	/* Fault them in here, from user space. */
-	for (; (unsigned long)p < gup.addr + size; p += psize())
+	for (p = addr; (unsigned long)p < (unsigned long)addr + size;
+	     p += psize())
 		p[0] = 0;
 
-	tid = malloc(sizeof(pthread_t) * nthreads);
-	assert(tid);
-	for (i = 0; i < nthreads; i++) {
-		ret = pthread_create(&tid[i], NULL, gup_thread, &gup);
-		assert(ret == 0);
-	}
-	for (i = 0; i < nthreads; i++) {
-		ret = pthread_join(tid[i], NULL);
-		assert(ret == 0);
+	gup.addr = (unsigned long)addr;
+	gup.size = size;
+	gup.nr_pages_per_call = size / psize();
+	gup.gup_flags = FOLL_WRITE;
+	gup.which_pages[0] = 1;
+	gup.which_pages[1] = 20;
+	gup.which_pages[2] = 0x1001;
+
+	/*
+	 * Preserve the old "./gup_test -ct -F 0x1 0 19 0x1000" sparse dump
+	 * coverage after removing command-line parsing from this binary.
+	 */
+	ASSERT_EQ(ioctl(gup_fd, DUMP_USER_PAGES_TEST, &gup), 0);
+
+	munmap(addr, size);
+	close(gup_fd);
+}
+
+int main(int argc, char **argv)
+{
+	int fd;
+	char *file = "/dev/zero";
+
+	fd = open(file, O_RDWR);
+	if (fd < 0) {
+		ksft_print_header();
+		ksft_exit_fail_msg("Unable to open %s: %s\n", file, strerror(errno));
 	}
+	close(fd);
 
-	free(tid);
+	fd = open(GUP_TEST_FILE, O_RDWR);
+	if (fd == -1) {
+		ksft_print_header();
+		if (errno == EACCES)
+			ksft_exit_skip("Please run this test as root\n");
+		if (errno == ENOENT) {
+			DIR *debugfs = opendir("/sys/kernel/debug");
+
+			if (!debugfs) {
+				ksft_exit_skip("Mount debugfs at /sys/kernel/debug\n");
+			} else {
+				closedir(debugfs);
+				ksft_exit_skip("Check CONFIG_GUP_TEST in kernel config\n");
+			}
+		}
+		ksft_exit_skip("failed to open %s: %s\n", GUP_TEST_FILE, strerror(errno));
+	}
+	close(fd);
 
-	ksft_exit_pass();
+	return test_harness_run(argc, argv);
 }
diff --git a/tools/testing/selftests/mm/run_vmtests.sh b/tools/testing/selftests/mm/run_vmtests.sh
index 8c296dedf047..56df0dcc9640 100755
--- a/tools/testing/selftests/mm/run_vmtests.sh
+++ b/tools/testing/selftests/mm/run_vmtests.sh
@@ -130,30 +130,6 @@ test_selected() {
 	fi
 }
 
-run_gup_matrix() {
-    # -t: thp=on, -T: thp=off, -H: hugetlb=on
-    local hugetlb_mb=256
-
-    for huge in -t -T "-H -m $hugetlb_mb"; do
-        # -u: gup-fast, -U: gup-basic, -a: pin-fast, -b: pin-basic, -L: pin-longterm
-        for test_cmd in -u -U -a -b -L; do
-            # -w: write=1, -W: write=0
-            for write in -w -W; do
-                # -S: shared
-                for share in -S " "; do
-                    # -n: How many pages to fetch together?  512 is special
-                    # because it's default thp size (or 2M on x86), 123 to
-                    # just test partial gup when hit a huge in whatever form
-                    for num in "-n 1" "-n 512" "-n 123" "-n -1"; do
-                        CATEGORY="gup_test" run_test ./gup_test \
-                                $huge $test_cmd $write $share $num
-                    done
-                done
-            done
-        done
-    done
-}
-
 # filter 64bit architectures
 ARCH64STR="arm64 mips64 parisc64 ppc64 ppc64le riscv64 s390x sparc64 x86_64"
 if [ -z "$ARCH" ]; then
@@ -276,18 +252,7 @@ fi
 
 CATEGORY="mmap" run_test ./map_fixed_noreplace
 
-if $RUN_ALL; then
-    run_gup_matrix
-else
-    # get_user_pages_fast() benchmark
-    CATEGORY="gup_test" run_test ./gup_test -u -n 1
-    CATEGORY="gup_test" run_test ./gup_test -u -n -1
-    # pin_user_pages_fast() benchmark
-    CATEGORY="gup_test" run_test ./gup_test -a -n 1
-    CATEGORY="gup_test" run_test ./gup_test -a -n -1
-fi
-# Dump pages 0, 19, and 4096, using pin_user_pages:
-CATEGORY="gup_test" run_test ./gup_test -ct -F 0x1 0 19 0x1000
+CATEGORY="gup_test" run_test ./gup_test
 CATEGORY="gup_test" run_test ./gup_longterm
 
 CATEGORY="userfaultfd" run_test ./uffd-unit-tests
-- 
2.39.5