add support for specifying process priority

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

2 files changed, 17 insertions, 0 deletions

diff --git a/instance.c b/instance.c
index b84e7c8..a25f91a 100644
--- a/instance.c
+++ b/instance.c
@@ -1,3 +1,4 @@
+#include <sys/resource.h>
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <net/if.h>
@@ -12,6 +13,7 @@ enum {
 	INSTANCE_ATTR_ENV,
 	INSTANCE_ATTR_DATA,
 	INSTANCE_ATTR_NETDEV,
+	INSTANCE_ATTR_NICE,
 	__INSTANCE_ATTR_MAX
 };
 
@@ -20,6 +22,7 @@ static const struct blobmsg_policy instance_attr[__INSTANCE_ATTR_MAX] = {
 	[INSTANCE_ATTR_ENV] = { "env", BLOBMSG_TYPE_TABLE },
 	[INSTANCE_ATTR_DATA] = { "data", BLOBMSG_TYPE_TABLE },
 	[INSTANCE_ATTR_NETDEV] = { "netdev", BLOBMSG_TYPE_ARRAY },
+	[INSTANCE_ATTR_NICE] = { "nice", BLOBMSG_TYPE_INT32 },
 };
 
 struct instance_netdev {
@@ -36,6 +39,9 @@ instance_run(struct service_instance *in)
 	int argc = 1; /* NULL terminated */
 	int rem;
 
+	if (in->nice)
+		setpriority(PRIO_PROCESS, 0, in->nice);
+
 	blobmsg_for_each_attr(cur, in->command, rem)
 		argc++;
 
@@ -129,6 +135,9 @@ instance_config_changed(struct service_instance *in, struct service_instance *in
 	if (!blobmsg_list_equal(&in->netdev, &in_new->netdev))
 		return true;
 
+	if (in->nice != in_new->nice)
+		return true;
+
 	return false;
 }
 
@@ -176,6 +185,12 @@ instance_config_parse(struct service_instance *in)
 
 	in->command = cur;
 
+	if ((cur = tb[INSTANCE_ATTR_NICE])) {
+		in->nice = (int8_t) blobmsg_get_u32(cur);
+		if (in->nice < -20 || in->nice > 20)
+			return false;
+	}
+
 	if ((cur = tb[INSTANCE_ATTR_ENV])) {
 		if (!blobmsg_check_attr_list(cur, BLOBMSG_TYPE_STRING))
 			return false;
diff --git a/instance.h b/instance.h
index 59e887c..484c856 100644
--- a/instance.h
+++ b/instance.h
@@ -10,8 +10,10 @@ struct service_instance {
 	struct service *srv;
 	const char *name;
 
+	int8_t nice;
 	bool valid;
 	bool restart;
+
 	struct blob_attr *config;
 	struct uloop_process proc;
 	struct uloop_timeout timeout;