Add monitor delay parameter to mdadm.conf

Add possibility to configure delay for mdadm in monitoring mode
using mdadm.conf.
--delay command line argument takes precedence over config file.

Signed-off-by: Oleksandr Shchirskyi <oleksandr.shchirskyi@intel.com>
Signed-off-by: Mariusz Tkaczyk <mariusz.tkaczyk@linux.intel.com>
Signed-off-by: Jes Sorensen <jsorensen@fb.com>

config.c

@@ -81,7 +81,7 @@ char DefaultAltConfDir[] = CONFFILE2 ".d";
 
 enum linetype { Devices, Array, Mailaddr, Mailfrom, Program, CreateDev,
 		Homehost, HomeCluster, AutoMode, Policy, PartPolicy, Sysfs,
-		LTEnd };
+		MonitorDelay, LTEnd };
 char *keywords[] = {
 	[Devices]  = "devices",
 	[Array]    = "array",
@@ -95,6 +95,7 @@ char *keywords[] = {
 	[Policy]   = "policy",
 	[PartPolicy]="part-policy",
 	[Sysfs]    = "sysfs",
+	[MonitorDelay] = "monitordelay",
 	[LTEnd]    = NULL
 };
 
@@ -588,6 +589,17 @@ void homeclusterline(char *line)
 	}
 }
 
+static int monitor_delay;
+void monitordelayline(char *line)
+{
+	char *w;
+
+	for (w = dl_next(line); w != line; w = dl_next(w)) {
+		if (monitor_delay == 0)
+			monitor_delay = strtol(w, NULL, 10);
+	}
+}
+
 char auto_yes[] = "yes";
 char auto_no[] = "no";
 char auto_homehost[] = "homehost";
@@ -769,6 +781,9 @@ void conf_file(FILE *f)
 		case Sysfs:
 			sysfsline(line);
 			break;
+		case MonitorDelay:
+			monitordelayline(line);
+			break;
 		default:
 			pr_err("Unknown keyword %s\n", line);
 		}
@@ -925,6 +940,12 @@ char *conf_get_homecluster(void)
 	return home_cluster;
 }
 
+int conf_get_monitor_delay(void)
+{
+	load_conffile();
+	return monitor_delay;
+}
+
 struct createinfo *conf_get_create_info(void)
 {
 	load_conffile();

mdadm.c

@@ -1659,10 +1659,8 @@ int main(int argc, char *argv[])
 			break;
 		}
 		if (c.delay == 0) {
-			if (get_linux_version() > 2006016)
-				/* mdstat responds to poll */
-				c.delay = 1000;
-			else
+			c.delay = conf_get_monitor_delay();
+			if (!c.delay)
 				c.delay = 60;
 		}
 		rv = Monitor(devlist, mailaddr, program,

mdadm.conf.5

@@ -505,7 +505,7 @@ Keywords used in the
 .I POLICY
 line and supported values are:
 
-.RS 7
+.RS 4
 .TP
 .B domain=
 any arbitrary string
@@ -589,7 +589,9 @@ found.
 
 .TP
 .B SYSFS
-The SYSFS line lists custom values of MD device's sysfs attributes which will be
+The
+.B SYSFS
+line lists custom values of MD device's sysfs attributes which will be
 stored in sysfs after the array is assembled. Multiple lines are allowed and each
 line has to contain the uuid or the name of the device to which it relates.
 .RS 4
@@ -604,8 +606,22 @@ name of the MD device as was given to
 when the array was created. It will be ignored if
 .B uuid
 is not empty.
+.RE
+
 .TP
-.RS 7
+.B MONITORDELAY
+The
+.B monitordelay
+line gives a delay in seconds
+.I mdadm
+shall wait before pooling md arrays
+when
+.I mdadm
+is running in
+.B \-\-monitor
+mode.
+.B \-d/\-\-delay
+command line argument takes precedence over the config file
 
 .SH EXAMPLE
 DEVICE /dev/sd[bcdjkl]1
@@ -682,6 +698,8 @@ SYSFS name=/dev/md/raid5 group_thread_cnt=4 sync_speed_max=1000000
 .br
 SYSFS uuid=bead5eb6:31c17a27:da120ba2:7dfda40d group_thread_cnt=4
 sync_speed_max=1000000
+.br
+MONITORDELAY 60
 
 .SH SEE ALSO
 .BR mdadm (8),

mdadm.h

@@ -1525,6 +1525,7 @@ extern char *conf_get_mailfrom(void);
 extern char *conf_get_program(void);
 extern char *conf_get_homehost(int *require_homehostp);
 extern char *conf_get_homecluster(void);
+extern int conf_get_monitor_delay(void);
 extern char *conf_line(FILE *file);
 extern char *conf_word(FILE *file, int allow_key);
 extern void print_quoted(char *str);