From 0bb52cf9985bda47e13940761b3d8e2eaddf377c Mon Sep 17 00:00:00 2001

From: Kazunori INOUE <kazunori_inoue@newson.co.jp>

Date: Wed, 10 Aug 2022 17:35:54 +0900

Subject: [PATCH 1/4] storage_mon: Use the O_DIRECT flag in open() to eliminate

 cache effects

---

 tools/Makefile.am   |  1 +

 tools/storage_mon.c | 82 +++++++++++++++++++++++++++++++++------------

 2 files changed, 61 insertions(+), 22 deletions(-)

diff --git a/tools/Makefile.am b/tools/Makefile.am

index 1309223b4..08323fee3 100644

--- a/tools/Makefile.am

+++ b/tools/Makefile.am

@@ -74,6 +74,7 @@ sfex_stat_LDADD		= $(GLIBLIB) -lplumb -lplumbgpl

 findif_SOURCES		= findif.c

 storage_mon_SOURCES	= storage_mon.c

+storage_mon_CFLAGS	= -D_GNU_SOURCE

 if BUILD_TICKLE

 halib_PROGRAMS		+= tickle_tcp

diff --git a/tools/storage_mon.c b/tools/storage_mon.c

index 930ead41c..ba87492fc 100644

--- a/tools/storage_mon.c

+++ b/tools/storage_mon.c

@@ -31,23 +31,27 @@ static void usage(char *name, FILE *f)

 	fprintf(f, "      --help           print this message\n");

 }

-/* Check one device */

-static void *test_device(const char *device, int verbose, int inject_error_percent)

+static int open_device(const char *device, int verbose)

 {

-	uint64_t devsize;

 	int device_fd;

 	int res;

+	uint64_t devsize;

 	off_t seek_spot;

-	char buffer[512];

-	if (verbose) {

-		printf("Testing device %s\n", device);

+#if defined(__linux__) || defined(__FreeBSD__)

+	device_fd = open(device, O_RDONLY|O_DIRECT);

+	if (device_fd >= 0) {

+		return device_fd;

+	} else if (errno != EINVAL) {

+		fprintf(stderr, "Failed to open %s: %s\n", device, strerror(errno));

+		return -1;

 	}

+#endif

 	device_fd = open(device, O_RDONLY);

 	if (device_fd < 0) {

 		fprintf(stderr, "Failed to open %s: %s\n", device, strerror(errno));

-		exit(-1);

+		return -1;

 	}

 #ifdef __FreeBSD__

 	res = ioctl(device_fd, DIOCGMEDIASIZE, &devsize);

@@ -57,11 +61,12 @@ static void *test_device(const char *device, int verbose, int inject_error_perce

 	if (res != 0) {

 		fprintf(stderr, "Failed to stat %s: %s\n", device, strerror(errno));

 		close(device_fd);

-		exit(-1);

+		return -1;

 	}

 	if (verbose) {

 		fprintf(stderr, "%s: size=%zu\n", device, devsize);

 	}

+

 	/* Don't fret about real randomness */

 	srand(time(NULL) + getpid());

 	/* Pick a random place on the device - sector aligned */

@@ -70,35 +75,64 @@ static void *test_device(const char *device, int verbose, int inject_error_perce

 	if (res < 0) {

 		fprintf(stderr, "Failed to seek %s: %s\n", device, strerror(errno));

 		close(device_fd);

-		exit(-1);

+		return -1;

 	}

-

 	if (verbose) {

 		printf("%s: reading from pos %ld\n", device, seek_spot);

 	}

+	return device_fd;

+}

+

+/* Check one device */

+static void *test_device(const char *device, int verbose, int inject_error_percent)

+{

+	int device_fd;

+	int sec_size = 0;

+	int res;

+	void *buffer;

+

+	if (verbose) {

+		printf("Testing device %s\n", device);

+	}

+

+	device_fd = open_device(device, verbose);

+	if (device_fd < 0) {

+		exit(-1);

+	}

+

+	ioctl(device_fd, BLKSSZGET, &sec_size);

+	if (sec_size == 0) {

+		fprintf(stderr, "Failed to stat %s: %s\n", device, strerror(errno));

+		goto error;

+	}

-	res = read(device_fd, buffer, sizeof(buffer));

+	if (posix_memalign(&buffer, sysconf(_SC_PAGESIZE), sec_size) != 0) {

+		fprintf(stderr, "Failed to allocate aligned memory: %s\n", strerror(errno));

+		goto error;

+	}

+

+	res = read(device_fd, buffer, sec_size);

+	free(buffer);

 	if (res < 0) {

 		fprintf(stderr, "Failed to read %s: %s\n", device, strerror(errno));

-		close(device_fd);

-		exit(-1);

+		goto error;

 	}

-	if (res < (int)sizeof(buffer)) {

-		fprintf(stderr, "Failed to read %ld bytes from %s, got %d\n", sizeof(buffer), device, res);

-		close(device_fd);

-		exit(-1);

+	if (res < sec_size) {

+		fprintf(stderr, "Failed to read %d bytes from %s, got %d\n", sec_size, device, res);

+		goto error;

 	}

 	/* Fake an error */

-	if (inject_error_percent && ((rand() % 100) < inject_error_percent)) {

-		fprintf(stderr, "People, please fasten your seatbelts, injecting errors!\n");

-		close(device_fd);

-		exit(-1);

+	if (inject_error_percent) {

+		srand(time(NULL) + getpid());

+		if ((rand() % 100) < inject_error_percent) {

+			fprintf(stderr, "People, please fasten your seatbelts, injecting errors!\n");

+			goto error;

+		}

 	}

 	res = close(device_fd);

 	if (res != 0) {

 		fprintf(stderr, "Failed to close %s: %s\n", device, strerror(errno));

-		close(device_fd);

 		exit(-1);

 	}

@@ -106,6 +140,10 @@ static void *test_device(const char *device, int verbose, int inject_error_perce

 		printf("%s: done\n", device);

 	}

 	exit(0);

+

+error:

+	close(device_fd);

+	exit(-1);

 }

 int main(int argc, char *argv[])

From ce4e632f29ed6b86b82a959eac5844655baed153 Mon Sep 17 00:00:00 2001

From: Kazunori INOUE <kazunori_inoue@newson.co.jp>

Date: Mon, 15 Aug 2022 19:17:21 +0900

Subject: [PATCH 2/4] storage_mon: fix build-related issues

---

 tools/storage_mon.c | 6 ++++--

 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/tools/storage_mon.c b/tools/storage_mon.c

index ba87492fc..e34d1975a 100644

--- a/tools/storage_mon.c

+++ b/tools/storage_mon.c

@@ -38,7 +38,6 @@ static int open_device(const char *device, int verbose)

 	uint64_t devsize;

 	off_t seek_spot;

-#if defined(__linux__) || defined(__FreeBSD__)

 	device_fd = open(device, O_RDONLY|O_DIRECT);

 	if (device_fd >= 0) {

 		return device_fd;

@@ -46,7 +45,6 @@ static int open_device(const char *device, int verbose)

 		fprintf(stderr, "Failed to open %s: %s\n", device, strerror(errno));

 		return -1;

 	}

-#endif

 	device_fd = open(device, O_RDONLY);

 	if (device_fd < 0) {

@@ -100,7 +98,11 @@ static void *test_device(const char *device, int verbose, int inject_error_perce

 		exit(-1);

 	}

+#ifdef __FreeBSD__

+	ioctl(device_fd, DIOCGSECTORSIZE, &sec_size);

+#else

 	ioctl(device_fd, BLKSSZGET, &sec_size);

+#endif

 	if (sec_size == 0) {

 		fprintf(stderr, "Failed to stat %s: %s\n", device, strerror(errno));

 		goto error;

From 7a0aaa0dfdebeab3fae9fe9ddc412c3d1f610273 Mon Sep 17 00:00:00 2001

From: Kazunori INOUE <kazunori_inoue@newson.co.jp>

Date: Wed, 24 Aug 2022 17:36:23 +0900

Subject: [PATCH 3/4] storage_mon: do random lseek even with O_DIRECT, etc

---

 tools/storage_mon.c | 118 ++++++++++++++++++++++----------------------

 1 file changed, 58 insertions(+), 60 deletions(-)

diff --git a/tools/storage_mon.c b/tools/storage_mon.c

index e34d1975a..0bdb48649 100644

--- a/tools/storage_mon.c

+++ b/tools/storage_mon.c

@@ -31,38 +31,43 @@ static void usage(char *name, FILE *f)

 	fprintf(f, "      --help           print this message\n");

 }

-static int open_device(const char *device, int verbose)

+/* Check one device */

+static void *test_device(const char *device, int verbose, int inject_error_percent)

 {

+	uint64_t devsize;

+	int flags = O_RDONLY | O_DIRECT;

 	int device_fd;

 	int res;

-	uint64_t devsize;

 	off_t seek_spot;

-	device_fd = open(device, O_RDONLY|O_DIRECT);

-	if (device_fd >= 0) {

-		return device_fd;

-	} else if (errno != EINVAL) {

-		fprintf(stderr, "Failed to open %s: %s\n", device, strerror(errno));

-		return -1;

+	if (verbose) {

+		printf("Testing device %s\n", device);

 	}

-	device_fd = open(device, O_RDONLY);

+	device_fd = open(device, flags);

 	if (device_fd < 0) {

-		fprintf(stderr, "Failed to open %s: %s\n", device, strerror(errno));

-		return -1;

+		if (errno != EINVAL) {

+			fprintf(stderr, "Failed to open %s: %s\n", device, strerror(errno));

+			exit(-1);

+		}

+		flags &= ~O_DIRECT;

+		device_fd = open(device, flags);

+		if (device_fd < 0) {

+			fprintf(stderr, "Failed to open %s: %s\n", device, strerror(errno));

+			exit(-1);

+		}

 	}

 #ifdef __FreeBSD__

 	res = ioctl(device_fd, DIOCGMEDIASIZE, &devsize);

 #else

 	res = ioctl(device_fd, BLKGETSIZE64, &devsize);

 #endif

-	if (res != 0) {

+	if (res < 0) {

 		fprintf(stderr, "Failed to stat %s: %s\n", device, strerror(errno));

-		close(device_fd);

-		return -1;

+		goto error;

 	}

 	if (verbose) {

-		fprintf(stderr, "%s: size=%zu\n", device, devsize);

+		printf("%s: opened %s O_DIRECT, size=%zu\n", device, (flags & O_DIRECT)?"with":"without", devsize);

 	}

 	/* Don't fret about real randomness */

@@ -72,65 +77,58 @@ static int open_device(const char *device, int verbose)

 	res = lseek(device_fd, seek_spot, SEEK_SET);

 	if (res < 0) {

 		fprintf(stderr, "Failed to seek %s: %s\n", device, strerror(errno));

-		close(device_fd);

-		return -1;

+		goto error;

 	}

 	if (verbose) {

 		printf("%s: reading from pos %ld\n", device, seek_spot);

 	}

-	return device_fd;

-}

-

-/* Check one device */

-static void *test_device(const char *device, int verbose, int inject_error_percent)

-{

-	int device_fd;

-	int sec_size = 0;

-	int res;

-	void *buffer;

-

-	if (verbose) {

-		printf("Testing device %s\n", device);

-	}

-	device_fd = open_device(device, verbose);

-	if (device_fd < 0) {

-		exit(-1);

-	}

+	if (flags & O_DIRECT) {

+		int sec_size = 0;

+		void *buffer;

 #ifdef __FreeBSD__

-	ioctl(device_fd, DIOCGSECTORSIZE, &sec_size);

+		res = ioctl(device_fd, DIOCGSECTORSIZE, &sec_size);

 #else

-	ioctl(device_fd, BLKSSZGET, &sec_size);

+		res = ioctl(device_fd, BLKSSZGET, &sec_size);

 #endif

-	if (sec_size == 0) {

-		fprintf(stderr, "Failed to stat %s: %s\n", device, strerror(errno));

-		goto error;

-	}

+		if (res < 0) {

+			fprintf(stderr, "Failed to stat %s: %s\n", device, strerror(errno));

+			goto error;

+		}

-	if (posix_memalign(&buffer, sysconf(_SC_PAGESIZE), sec_size) != 0) {

-		fprintf(stderr, "Failed to allocate aligned memory: %s\n", strerror(errno));

-		goto error;

-	}

+		if (posix_memalign(&buffer, sysconf(_SC_PAGESIZE), sec_size) != 0) {

+			fprintf(stderr, "Failed to allocate aligned memory: %s\n", strerror(errno));

+			goto error;

+		}

+		res = read(device_fd, buffer, sec_size);

+		free(buffer);

+		if (res < 0) {

+			fprintf(stderr, "Failed to read %s: %s\n", device, strerror(errno));

+			goto error;

+		}

+		if (res < sec_size) {

+			fprintf(stderr, "Failed to read %d bytes from %s, got %d\n", sec_size, device, res);

+			goto error;

+		}

+	} else {

+		char buffer[512];

-	res = read(device_fd, buffer, sec_size);

-	free(buffer);

-	if (res < 0) {

-		fprintf(stderr, "Failed to read %s: %s\n", device, strerror(errno));

-		goto error;

-	}

-	if (res < sec_size) {

-		fprintf(stderr, "Failed to read %d bytes from %s, got %d\n", sec_size, device, res);

-		goto error;

+		res = read(device_fd, buffer, sizeof(buffer));

+		if (res < 0) {

+			fprintf(stderr, "Failed to read %s: %s\n", device, strerror(errno));

+			goto error;

+		}

+		if (res < (int)sizeof(buffer)) {

+			fprintf(stderr, "Failed to read %ld bytes from %s, got %d\n", sizeof(buffer), device, res);

+			goto error;

+		}

 	}

 	/* Fake an error */

-	if (inject_error_percent) {

-		srand(time(NULL) + getpid());

-		if ((rand() % 100) < inject_error_percent) {

-			fprintf(stderr, "People, please fasten your seatbelts, injecting errors!\n");

-			goto error;

-		}

+	if (inject_error_percent && ((rand() % 100) < inject_error_percent)) {

+		fprintf(stderr, "People, please fasten your seatbelts, injecting errors!\n");

+		goto error;

 	}

 	res = close(device_fd);

 	if (res != 0) {

From db97e055a17526cec056c595844a9d8851e3ee19 Mon Sep 17 00:00:00 2001

From: Kazunori INOUE <kazunori_inoue@newson.co.jp>

Date: Thu, 25 Aug 2022 16:03:46 +0900

Subject: [PATCH 4/4] storage_mon: improve error messages when ioctl() fails

---

 tools/storage_mon.c | 4 ++--

 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/storage_mon.c b/tools/storage_mon.c

index 0bdb48649..f829c5081 100644

--- a/tools/storage_mon.c

+++ b/tools/storage_mon.c

@@ -63,7 +63,7 @@ static void *test_device(const char *device, int verbose, int inject_error_perce

 	res = ioctl(device_fd, BLKGETSIZE64, &devsize);

 #endif

 	if (res < 0) {

-		fprintf(stderr, "Failed to stat %s: %s\n", device, strerror(errno));

+		fprintf(stderr, "Failed to get device size for %s: %s\n", device, strerror(errno));

 		goto error;

 	}

 	if (verbose) {

@@ -93,7 +93,7 @@ static void *test_device(const char *device, int verbose, int inject_error_perce

 		res = ioctl(device_fd, BLKSSZGET, &sec_size);

 #endif

 		if (res < 0) {

-			fprintf(stderr, "Failed to stat %s: %s\n", device, strerror(errno));

+			fprintf(stderr, "Failed to get block device sector size for %s: %s\n", device, strerror(errno));

 			goto error;

 		}