diff mbox series

[RFC,v2,5/5] selftest/userfaultfd: test read/write hints

Message ID 20220619233449.181323-6-namit@vmware.com (mailing list archive)
State New
Headers show
Series userfaultfd: support access/write hints | expand

Commit Message

Nadav Amit June 19, 2022, 11:34 p.m. UTC 
From: Nadav Amit <namit@vmware.com>

Test UFFDIO_*_MODE_ACCESS_LIKELY and UFFDIO_*_MODE_WRITE_LIKELY.
Introduce a modifier to trigger the use of the hints.

Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Nadav Amit <namit@vmware.com>
---
 tools/testing/selftests/vm/userfaultfd.c | 26 ++++++++++++++++++++++++
 1 file changed, 26 insertions(+)
diff mbox series

Patch

diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c
index 28b881523d15..01680a7d1cdd 100644
--- a/tools/testing/selftests/vm/userfaultfd.c
+++ b/tools/testing/selftests/vm/userfaultfd.c
@@ -88,6 +88,8 @@  static volatile bool test_uffdio_zeropage_eexist = true;
 static bool test_uffdio_wp = true;
 /* Whether to test uffd minor faults */
 static bool test_uffdio_minor = false;
+static bool test_access_likely;
+static bool test_write_likely;
 
 static bool map_shared;
 static int shm_fd;
@@ -550,6 +552,12 @@  static void wp_range(int ufd, __u64 start, __u64 len, bool wp)
 	/* Undo write-protect, do wakeup after that */
 	prms.mode = wp ? UFFDIO_WRITEPROTECT_MODE_WP : 0;
 
+	if (test_access_likely)
+		prms.mode |= UFFDIO_WRITEPROTECT_MODE_ACCESS_LIKELY;
+
+	if (test_write_likely)
+		prms.mode |= UFFDIO_WRITEPROTECT_MODE_WRITE_LIKELY;
+
 	if (ioctl(ufd, UFFDIO_WRITEPROTECT, &prms))
 		err("clear WP failed: address=0x%"PRIx64, (uint64_t)start);
 }
@@ -653,6 +661,13 @@  static int __copy_page(int ufd, unsigned long offset, bool retry)
 		uffdio_copy.mode = UFFDIO_COPY_MODE_WP;
 	else
 		uffdio_copy.mode = 0;
+
+	if (test_access_likely)
+		uffdio_copy.mode |= UFFDIO_COPY_MODE_ACCESS_LIKELY;
+
+	if (test_write_likely)
+		uffdio_copy.mode |= UFFDIO_COPY_MODE_WRITE_LIKELY;
+
 	uffdio_copy.copy = 0;
 	if (ioctl(ufd, UFFDIO_COPY, &uffdio_copy)) {
 		/* real retval in ufdio_copy.copy */
@@ -1080,6 +1095,13 @@  static int __uffdio_zeropage(int ufd, unsigned long offset, bool retry)
 	uffdio_zeropage.range.start = (unsigned long) area_dst + offset;
 	uffdio_zeropage.range.len = page_size;
 	uffdio_zeropage.mode = 0;
+
+	if (test_access_likely)
+		uffdio_zeropage.mode |= UFFDIO_ZEROPAGE_MODE_ACCESS_LIKELY;
+
+	if (test_write_likely)
+		uffdio_zeropage.mode |= UFFDIO_ZEROPAGE_MODE_WRITE_LIKELY;
+
 	ret = ioctl(ufd, UFFDIO_ZEROPAGE, &uffdio_zeropage);
 	res = uffdio_zeropage.zeropage;
 	if (ret) {
@@ -1648,6 +1670,10 @@  static void parse_test_type_arg(const char *raw_type)
 			set_test_type(token);
 		else if (!strcmp(token, "dev"))
 			test_dev_userfaultfd = true;
+		else if (!strcmp(token, "access_likely"))
+			test_access_likely = true;
+		else if (!strcmp(token, "write_likely"))
+			test_write_likely = true;
 		else
 			err("unrecognized test mod '%s'", token);
 	}