[v4,5/6] syscalls/readahead02: test readahead() on an overlayfs file
diff mbox series

Message ID 20181128164645.783-6-amir73il@gmail.com
State Superseded
Headers show
Series
  • Tests for readahead() and fadvise() on overlayfs
Related show

Commit Message

Amir Goldstein Nov. 28, 2018, 4:46 p.m. UTC
Repeat the test case on an overlayfs file.

The new test case is a regression test for kernel commit b833a3660394
("ovl: add ovl_fadvise()") which fixes a regression of readahead() on
an overlay file that was introduced by kernel commit 5b910bd615ba
("ovl: fix GPF in swapfile_activate of file from overlayfs over xfs").

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
---
 .../kernel/syscalls/readahead/readahead02.c   | 80 ++++++++++++++++---
 1 file changed, 71 insertions(+), 9 deletions(-)

Comments

Cyril Hrubis Dec. 4, 2018, 2:02 p.m. UTC | #1
Hi!
> The new test case is a regression test for kernel commit b833a3660394
> ("ovl: add ovl_fadvise()") which fixes a regression of readahead() on
> an overlay file that was introduced by kernel commit 5b910bd615ba
> ("ovl: fix GPF in swapfile_activate of file from overlayfs over xfs").

I've pushed the patches up to this patch with the change to the error
propagation as we agreed and:

* Added commit hashes of the two commits mentioned in this changelog
  to the top level comment of this test, since this is the place where
  testers look first for this kind of information.

+ Added one simplification patch on the top of this

I will look closer at the last one now.

Thanks for your work on the test.

Patch
diff mbox series

diff --git a/testcases/kernel/syscalls/readahead/readahead02.c b/testcases/kernel/syscalls/readahead/readahead02.c
index 24f045900..73c8a6ce6 100644
--- a/testcases/kernel/syscalls/readahead/readahead02.c
+++ b/testcases/kernel/syscalls/readahead/readahead02.c
@@ -14,6 +14,7 @@ 
 #include <sys/types.h>
 #include <sys/syscall.h>
 #include <sys/mman.h>
+#include <sys/mount.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <errno.h>
@@ -33,8 +34,14 @@  static const char meminfo_fname[] = "/proc/meminfo";
 static size_t testfile_size = 64 * 1024 * 1024;
 static char *opt_fsizestr;
 static int pagesize;
+static unsigned long cached_max;
+static int ovl_mounted;
 
 #define MNTPOINT        "mntpoint"
+#define OVL_LOWER	MNTPOINT"/lower"
+#define OVL_UPPER	MNTPOINT"/upper"
+#define OVL_WORK	MNTPOINT"/work"
+#define OVL_MNT		MNTPOINT"/ovl"
 #define MIN_SANE_READAHEAD (4u * 1024u)
 
 static const char mntpoint[] = MNTPOINT;
@@ -44,6 +51,16 @@  static struct tst_option options[] = {
 	{NULL, NULL, NULL}
 };
 
+static struct tcase {
+	const char *tname;
+	int use_overlay;
+} tcases[] = {
+	{ "readahead on file", 0 },
+	{ "readahead on overlayfs file", 1 },
+};
+
+static int readahead_supported = 1;
+
 static int has_file(const char *fname, int required)
 {
 	struct stat buf;
@@ -97,12 +114,13 @@  static unsigned long get_cached_size(void)
 	return parse_entry(meminfo_fname, entry);
 }
 
-static void create_testfile(void)
+static void create_testfile(int use_overlay)
 {
 	int fd;
 	char *tmp;
 	size_t i;
 
+	sprintf(testfile, "%s/testfile", use_overlay ? OVL_MNT : MNTPOINT);
 	tst_res(TINFO, "creating test file of size: %zu", testfile_size);
 	tmp = SAFE_MALLOC(pagesize);
 
@@ -203,21 +221,33 @@  static void read_testfile(int do_readahead, const char *fname, size_t fsize,
 	SAFE_CLOSE(fd);
 }
 
-static void test_readahead(void)
+static void test_readahead(unsigned int n)
 {
 	unsigned long read_bytes, read_bytes_ra;
 	long long usec, usec_ra;
-	unsigned long cached_max, cached_low, cached, cached_ra;
+	unsigned long cached_high, cached_low, cached, cached_ra;
 	char proc_io_fname[128];
+	struct tcase *tc = &tcases[n];
+
+	tst_res(TINFO, "Test #%d: %s", n, tc->tname);
+
 	sprintf(proc_io_fname, "/proc/%u/io", getpid());
 
+	if (tc->use_overlay && !ovl_mounted) {
+		tst_res(TCONF,
+			"overlayfs is not configured in this kernel.");
+		return;
+	}
+
+	create_testfile(tc->use_overlay);
+
 	/* find out how much can cache hold if we read whole file */
 	read_testfile(0, testfile, testfile_size, &read_bytes, &usec, &cached);
-	cached_max = get_cached_size();
+	cached_high = get_cached_size();
 	sync();
 	drop_caches();
 	cached_low = get_cached_size();
-	cached_max = cached_max - cached_low;
+	cached_max = MAX(cached_max, cached_high - cached_low);
 
 	tst_res(TINFO, "read_testfile(0)");
 	read_testfile(0, testfile, testfile_size, &read_bytes, &usec, &cached);
@@ -233,11 +263,14 @@  static void test_readahead(void)
 	read_testfile(1, testfile, testfile_size, &read_bytes_ra,
 		      &usec_ra, &cached_ra);
 	if (TST_RET != 0) {
-		if (TST_ERR == EINVAL) {
+		if (TST_ERR == EINVAL &&
+		    (!tc->use_overlay || !readahead_supported)) {
+			readahead_supported = 0;
 			tst_res(TCONF, "readahead not supported on %s",
 				tst_device->fs_type);
 		} else {
 			tst_res(TFAIL | TTERRNO, "readahead failed on %s",
+				tc->use_overlay ? "overlayfs" :
 				tst_device->fs_type);
 		}
 		return;
@@ -284,6 +317,28 @@  static void test_readahead(void)
 	}
 }
 
+static void setup_overlay(void)
+{
+	int ret;
+
+	/* Setup an overlay mount with lower dir and file */
+	SAFE_MKDIR(OVL_LOWER, 0755);
+	SAFE_MKDIR(OVL_UPPER, 0755);
+	SAFE_MKDIR(OVL_WORK, 0755);
+	SAFE_MKDIR(OVL_MNT, 0755);
+	ret = mount("overlay", OVL_MNT, "overlay", 0, "lowerdir="OVL_LOWER
+		    ",upperdir="OVL_UPPER",workdir="OVL_WORK);
+	if (ret < 0) {
+		if (errno == ENODEV) {
+			tst_res(TINFO,
+				"overlayfs is not configured in this kernel.");
+			return;
+		}
+		tst_brk(TBROK | TERRNO, "overlayfs mount failed");
+	}
+	ovl_mounted = 1;
+}
+
 static void setup(void)
 {
 	if (opt_fsizestr)
@@ -297,8 +352,13 @@  static void setup(void)
 
 	pagesize = getpagesize();
 
-	sprintf(testfile, "%s/testfile", mntpoint);
-	create_testfile();
+	setup_overlay();
+}
+
+static void cleanup(void)
+{
+	if (ovl_mounted)
+		SAFE_UMOUNT(OVL_MNT);
 }
 
 static struct tst_test test = {
@@ -307,6 +367,8 @@  static struct tst_test test = {
 	.mount_device = 1,
 	.mntpoint = mntpoint,
 	.setup = setup,
+	.cleanup = cleanup,
 	.options = options,
-	.test_all = test_readahead,
+	.test = test_readahead,
+	.tcnt = ARRAY_SIZE(tcases),
 };