[PATCH v2 26/31] selftests/mm: Move zeropage test into uffd unit tests
From: Peter Xu
Date: Wed Apr 12 2023 - 12:46:52 EST
Simplifies it a bit along the way, e.g., drop the never used offset
field (which was always the 1st page so offset=0).
Introduce uffd_register_with_ioctls() out of uffd_register() to detect
uffdio_register.ioctls got returned. Check that automatically when testing
UFFDIO_ZEROPAGE on different types of memory (and kernel).
Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
---
tools/testing/selftests/mm/uffd-stress.c | 94 +-------------------
tools/testing/selftests/mm/uffd-unit-tests.c | 93 +++++++++++++++++++
tools/testing/selftests/mm/vm_util.c | 14 ++-
tools/testing/selftests/mm/vm_util.h | 2 +
4 files changed, 108 insertions(+), 95 deletions(-)
diff --git a/tools/testing/selftests/mm/uffd-stress.c b/tools/testing/selftests/mm/uffd-stress.c
index ce51180238d8..d78f88850011 100644
--- a/tools/testing/selftests/mm/uffd-stress.c
+++ b/tools/testing/selftests/mm/uffd-stress.c
@@ -109,15 +109,6 @@ static inline uint64_t uffd_minor_feature(void)
return 0;
}
-static int my_bcmp(char *str1, char *str2, size_t n)
-{
- unsigned long i;
- for (i = 0; i < n; i++)
- if (str1[i] != str2[i])
- return 1;
- return 0;
-}
-
static void *locking_thread(void *arg)
{
unsigned long cpu = (unsigned long) arg;
@@ -273,89 +264,6 @@ static int stress(struct uffd_args *args)
return 0;
}
-static void retry_uffdio_zeropage(int ufd,
- struct uffdio_zeropage *uffdio_zeropage,
- unsigned long offset)
-{
- uffd_test_ops->alias_mapping(&uffdio_zeropage->range.start,
- uffdio_zeropage->range.len,
- offset);
- if (ioctl(ufd, UFFDIO_ZEROPAGE, uffdio_zeropage)) {
- if (uffdio_zeropage->zeropage != -EEXIST)
- err("UFFDIO_ZEROPAGE error: %"PRId64,
- (int64_t)uffdio_zeropage->zeropage);
- } else {
- err("UFFDIO_ZEROPAGE error: %"PRId64,
- (int64_t)uffdio_zeropage->zeropage);
- }
-}
-
-static int __uffdio_zeropage(int ufd, unsigned long offset)
-{
- struct uffdio_zeropage uffdio_zeropage;
- int ret;
- bool has_zeropage = !(test_type == TEST_HUGETLB);
- __s64 res;
-
- if (offset >= nr_pages * page_size)
- err("unexpected offset %lu", offset);
- uffdio_zeropage.range.start = (unsigned long) area_dst + offset;
- uffdio_zeropage.range.len = page_size;
- uffdio_zeropage.mode = 0;
- ret = ioctl(ufd, UFFDIO_ZEROPAGE, &uffdio_zeropage);
- res = uffdio_zeropage.zeropage;
- if (ret) {
- /* real retval in ufdio_zeropage.zeropage */
- if (has_zeropage)
- err("UFFDIO_ZEROPAGE error: %"PRId64, (int64_t)res);
- else if (res != -EINVAL)
- err("UFFDIO_ZEROPAGE not -EINVAL");
- } else if (has_zeropage) {
- if (res != page_size) {
- err("UFFDIO_ZEROPAGE unexpected size");
- } else {
- retry_uffdio_zeropage(ufd, &uffdio_zeropage,
- offset);
- return 1;
- }
- } else
- err("UFFDIO_ZEROPAGE succeeded");
-
- return 0;
-}
-
-static int uffdio_zeropage(int ufd, unsigned long offset)
-{
- return __uffdio_zeropage(ufd, offset);
-}
-
-/* exercise UFFDIO_ZEROPAGE */
-static int userfaultfd_zeropage_test(void)
-{
- printf("testing UFFDIO_ZEROPAGE: ");
- fflush(stdout);
-
- uffd_test_ctx_init(0);
-
- if (uffd_register(uffd, area_dst, nr_pages * page_size,
- true, test_uffdio_wp, false))
- err("register failure");
-
- if (area_dst_alias) {
- /* Needed this to test zeropage-retry on shared memory */
- if (uffd_register(uffd, area_dst_alias, nr_pages * page_size,
- true, test_uffdio_wp, false))
- err("register failure");
- }
-
- if (uffdio_zeropage(uffd, 0))
- if (my_bcmp(area_dst, zeropage, page_size))
- err("zeropage is not zero");
-
- printf("done.\n");
- return 0;
-}
-
static int userfaultfd_stress(void)
{
void *area;
@@ -467,7 +375,7 @@ static int userfaultfd_stress(void)
uffd_stats_report(args, nr_cpus);
}
- return userfaultfd_zeropage_test();
+ return 0;
}
static void set_test_type(const char *type)
diff --git a/tools/testing/selftests/mm/uffd-unit-tests.c b/tools/testing/selftests/mm/uffd-unit-tests.c
index 94549696f4b2..160bd8ccda55 100644
--- a/tools/testing/selftests/mm/uffd-unit-tests.c
+++ b/tools/testing/selftests/mm/uffd-unit-tests.c
@@ -660,7 +660,100 @@ static void uffd_events_wp_test(void)
uffd_events_test_common(true);
}
+static void retry_uffdio_zeropage(int ufd,
+ struct uffdio_zeropage *uffdio_zeropage)
+{
+ uffd_test_ops->alias_mapping(&uffdio_zeropage->range.start,
+ uffdio_zeropage->range.len,
+ 0);
+ if (ioctl(ufd, UFFDIO_ZEROPAGE, uffdio_zeropage)) {
+ if (uffdio_zeropage->zeropage != -EEXIST)
+ err("UFFDIO_ZEROPAGE error: %"PRId64,
+ (int64_t)uffdio_zeropage->zeropage);
+ } else {
+ err("UFFDIO_ZEROPAGE error: %"PRId64,
+ (int64_t)uffdio_zeropage->zeropage);
+ }
+}
+
+static bool do_uffdio_zeropage(int ufd, bool has_zeropage)
+{
+ struct uffdio_zeropage uffdio_zeropage = { 0 };
+ int ret;
+ __s64 res;
+
+ uffdio_zeropage.range.start = (unsigned long) area_dst;
+ uffdio_zeropage.range.len = page_size;
+ uffdio_zeropage.mode = 0;
+ ret = ioctl(ufd, UFFDIO_ZEROPAGE, &uffdio_zeropage);
+ res = uffdio_zeropage.zeropage;
+ if (ret) {
+ /* real retval in ufdio_zeropage.zeropage */
+ if (has_zeropage)
+ err("UFFDIO_ZEROPAGE error: %"PRId64, (int64_t)res);
+ else if (res != -EINVAL)
+ err("UFFDIO_ZEROPAGE not -EINVAL");
+ } else if (has_zeropage) {
+ if (res != page_size)
+ err("UFFDIO_ZEROPAGE unexpected size");
+ else
+ retry_uffdio_zeropage(ufd, &uffdio_zeropage);
+ return true;
+ } else
+ err("UFFDIO_ZEROPAGE succeeded");
+
+ return false;
+}
+
+/*
+ * Registers a range with MISSING mode only for zeropage test. Return true
+ * if UFFDIO_ZEROPAGE supported, false otherwise. Can't use uffd_register()
+ * because we want to detect .ioctls along the way.
+ */
+static bool
+uffd_register_detect_zeropage(int uffd, void *addr, uint64_t len)
+{
+ uint64_t ioctls = 0;
+
+ if (uffd_register_with_ioctls(uffd, addr, len, true,
+ false, false, &ioctls))
+ err("zeropage register fail");
+
+ return ioctls & (1 << _UFFDIO_ZEROPAGE);
+}
+
+/* exercise UFFDIO_ZEROPAGE */
+static void uffd_zeropage_test(void)
+{
+ bool has_zeropage;
+ int i;
+
+ has_zeropage = uffd_register_detect_zeropage(uffd, area_dst, page_size);
+ if (area_dst_alias)
+ /* Ignore the retval; we already have it */
+ uffd_register_detect_zeropage(uffd, area_dst_alias, page_size);
+
+ if (do_uffdio_zeropage(uffd, has_zeropage))
+ for (i = 0; i < page_size; i++)
+ if (area_dst[i] != 0)
+ err("data non-zero at offset %d\n", i);
+
+ if (uffd_unregister(uffd, area_dst, page_size))
+ err("unregister");
+
+ if (area_dst_alias && uffd_unregister(uffd, area_dst_alias, page_size))
+ err("unregister");
+
+ uffd_test_pass();
+}
+
uffd_test_case_t uffd_tests[] = {
+ {
+ .name = "zeropage",
+ .uffd_fn = uffd_zeropage_test,
+ .mem_targets = MEM_ALL,
+ .uffd_feature_required = 0,
+ },
{
.name = "pagemap",
.uffd_fn = uffd_pagemap_test,
diff --git a/tools/testing/selftests/mm/vm_util.c b/tools/testing/selftests/mm/vm_util.c
index 1bc0ceb01adb..9b06a5034808 100644
--- a/tools/testing/selftests/mm/vm_util.c
+++ b/tools/testing/selftests/mm/vm_util.c
@@ -198,8 +198,9 @@ unsigned long default_huge_page_size(void)
return hps;
}
-int uffd_register(int uffd, void *addr, uint64_t len,
- bool miss, bool wp, bool minor)
+/* If `ioctls' non-NULL, the allowed ioctls will be returned into the var */
+int uffd_register_with_ioctls(int uffd, void *addr, uint64_t len,
+ bool miss, bool wp, bool minor, uint64_t *ioctls)
{
struct uffdio_register uffdio_register = { 0 };
uint64_t mode = 0;
@@ -218,10 +219,19 @@ int uffd_register(int uffd, void *addr, uint64_t len,
if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register) == -1)
ret = -errno;
+ else if (ioctls)
+ *ioctls = uffdio_register.ioctls;
return ret;
}
+int uffd_register(int uffd, void *addr, uint64_t len,
+ bool miss, bool wp, bool minor)
+{
+ return uffd_register_with_ioctls(uffd, addr, len,
+ miss, wp, minor, NULL);
+}
+
int uffd_unregister(int uffd, void *addr, uint64_t len)
{
struct uffdio_range range = { .start = (uintptr_t)addr, .len = len };
diff --git a/tools/testing/selftests/mm/vm_util.h b/tools/testing/selftests/mm/vm_util.h
index 634eb2f41145..b950bd16083a 100644
--- a/tools/testing/selftests/mm/vm_util.h
+++ b/tools/testing/selftests/mm/vm_util.h
@@ -52,6 +52,8 @@ int uffd_open_dev(unsigned int flags);
int uffd_open_sys(unsigned int flags);
int uffd_open(unsigned int flags);
int uffd_get_features(uint64_t *features);
+int uffd_register_with_ioctls(int uffd, void *addr, uint64_t len,
+ bool miss, bool wp, bool minor, uint64_t *ioctls);
/*
* On ppc64 this will only work with radix 2M hugepage size
--
2.39.1