stress-dev: add --dev-alldev option to exercise all devices

This new option will exercise all devices; the default is
just to exercise the first occurrence +of a device (e.g. /dev/i2c-0),
this option will exercise all devices (e.g. /dev/i2c-*) and hence will
take far more time to work through all the devices.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>

Author: ColinIanKing

bash-completion/stress-ng

@@ -262,6 +262,7 @@ _stress_ng()
 	'--cpu-online-all' | \
 	'--daemon-wait' | \
 	'--dentry-negative' | \
+	'--dev-alldev' | \
 	'--dry-run' | \
 	'--epollmany-delete' | \
 	'--eventfd-nonblock' | \

core-opts.c

@@ -270,8 +270,10 @@ const struct option stress_long_options[] = {
 	{ "dentrystat",		1,	NULL,	OPT_dentrystat },
 
 	{ "dev",		1,	NULL,	OPT_dev },
+	{ "dev-alldev",		0,	NULL,	OPT_dev_alldev },
 	{ "dev-file",		1,	NULL,	OPT_dev_file },
 	{ "dev-ops",		1,	NULL,	OPT_dev_ops },
+
 	{ "dev-shm",		1,	NULL,	OPT_dev_shm },
 	{ "dev-shm-ops",	1,	NULL,	OPT_dev_shm_ops },
 

core-opts.h

@@ -396,6 +396,7 @@ typedef enum {
 	OPT_dentrystat,
 
 	OPT_dev,
+	OPT_dev_alldev,
 	OPT_dev_ops,
 	OPT_dev_file,
 

stress-dev.c

@@ -236,13 +236,15 @@ typedef struct dev_info {
 
 static const stress_help_t help[] = {
 	{ NULL,	"dev N",	"start N device entry thrashing stressors" },
+	{ NULL, "dev-alldev",   "exercise all devices (rather than just /dev/devname0)" },
 	{ NULL, "dev-file name","specify the /dev/ file to exercise" },
 	{ NULL,	"dev-ops N",	"stop after N device thrashing bogo ops" },
 	{ NULL,	NULL,		NULL }
 };
 
 static const stress_opt_t opts[] = {
-	{ OPT_dev_file, "dev-file", TYPE_ID_STR, 0, 0, NULL },
+	{ OPT_dev_alldev, "dev-alldev", TYPE_ID_BOOL, 0, 1, NULL },
+	{ OPT_dev_file,   "dev-file",   TYPE_ID_STR, 0, 0, NULL },
 	END_OPT,
 };
 
@@ -4467,7 +4469,8 @@ static void stress_dev_infos_get(
 	const char *path,
 	const char *tty_name,
 	dev_info_t **list,
-	size_t *list_len)
+	size_t *list_len,
+	const bool dev_alldev)
 {
 	struct dirent **dlist;
 	int i;
@@ -4498,10 +4501,10 @@ static void stress_dev_infos_get(
 		len = shim_strlen(d->d_name);
 
 		/*
-		 *  Exercise no more than 3 of the same device
+		 *  Exercise no more than 1 of the same device
 		 *  driver, e.g. ttyS0..ttyS1
 		 */
-		if (len > 1) {
+		if (!dev_alldev && (len > 1)) {
 			int dev_n;
 			char *ptr = d->d_name + len - 1;
 
@@ -4510,10 +4513,11 @@ static void stress_dev_infos_get(
 			ptr++;
 			if (sscanf(ptr, "%d", &dev_n) != 1)
 				continue;
-			if (dev_n > 2)
+			if (dev_n > 1)
 				continue;
 		}
 
+
 		(void)stress_fs_make_filename(tmp, sizeof(tmp), path, d->d_name);
 
 		/* Don't exercise our tty */
@@ -4527,7 +4531,7 @@ static void stress_dev_infos_get(
 				continue;
 			if ((statbuf.st_mode & flags) == 0)
 				continue;
-			stress_dev_infos_get(args, tmp, tty_name, list, list_len);
+			stress_dev_infos_get(args, tmp, tty_name, list, list_len, dev_alldev);
 			break;
 		case SHIM_DT_BLK:
 		case SHIM_DT_CHR:
@@ -4766,6 +4770,7 @@ static int stress_dev(stress_args_t *args)
 	size_t dev_info_list_len = 0;
 	sys_dev_info_t *sys_dev_info_list = NULL;
 	sys_dev_info_t *sys_dev_info_list_end = NULL;
+	bool dev_alldev = false;
 
 	stress_dev_state_init(&dev_state_null);
 
@@ -4774,6 +4779,7 @@ static int stress_dev(stress_args_t *args)
 
 	(void)shim_memset(ret, 0, sizeof(ret));
 
+	(void)stress_setting_get("dev-alldev", &dev_alldev);
 	(void)stress_setting_get("dev-file", &dev_file);
 	if (dev_file) {
 		mode_t mode;
@@ -4793,7 +4799,7 @@ static int stress_dev(stress_args_t *args)
 
 		stress_dev_info_add(args, dev_file, &dev_info_list, &dev_info_list_len, true);
 	} else {
-		stress_dev_infos_get(args, "/dev", tty_name, &dev_info_list, &dev_info_list_len);
+		stress_dev_infos_get(args, "/dev", tty_name, &dev_info_list, &dev_info_list_len, dev_alldev);
 		stress_sys_dev_infos_get(args, "/sys/dev", &sys_dev_info_list, &sys_dev_info_list_end, 0);
 	}
 

stress-ng.1

@@ -2880,8 +2880,14 @@ stop after N non-existtent files are accessed.
 .B \-\-dev N
 start N workers that exercise the /dev devices. Each worker runs 5
 concurrent threads that perform open(2), fstat(2), lseek(2), poll(2),
-fcntl(2), mmap(2), munmap(2), fsync(2) and close(2) on each device.
-Note that watchdog devices are not exercised.
+fcntl(2), mmap(2), munmap(2), fsync(2) and close(2) on the fist occurance
+of each device. Note that watchdog devices are not exercised.
+.TP
+.B \-\-dev\-alldev
+exercise all devices; the default is just to exercise
+the first occurrence of a device (e.g. /dev/i2c-0), this option will
+exercise all devices (e.g. /dev/i2c-*) and hence will take far more
+time to work through all the devices.
 .TP
 .B \-\-dev\-file filename
 specify the device file to exercise, for example, /dev/null. By default