From b94097567cbb116025f54772609eef7b9a8e3f4e Mon Sep 17 00:00:00 2001
From: Franco Fichtner <franco@opnsense.org>
Date: Thu, 24 Aug 2023 09:58:22 +0200
Subject: [PATCH] system: defer config reload to SIGHUP in gateway watcher

This should considerably lower CPU usage as reported a few times.
We do need to bring in pcntl PHP module in order to get that done
easily in the script.

PR: https://forum.opnsense.org/index.php?topic=35219.0
---
 Makefile                                        |  3 ++-
 src/etc/inc/plugins.inc.d/dpinger.inc           | 17 +++++++++++------
 src/opnsense/scripts/routes/gateway_watcher.php | 17 +++++++++++++----
 3 files changed, 26 insertions(+), 11 deletions(-)

diff --git a/Makefile b/Makefile
index cee72ad64..c1b2f85a8 100644
--- a/Makefile
+++ b/Makefile
@@ -167,9 +167,10 @@ CORE_DEPENDS?=		ca_root_nss \
 			php${CORE_PHP}-gettext \
 			php${CORE_PHP}-google-api-php-client \
 			php${CORE_PHP}-ldap \
+			php${CORE_PHP}-pcntl \
 			php${CORE_PHP}-pdo \
-			php${CORE_PHP}-pecl-radius \
 			php${CORE_PHP}-pear-Crypt_CHAP \
+			php${CORE_PHP}-pecl-radius \
 			php${CORE_PHP}-phalcon \
 			php${CORE_PHP}-phpseclib \
 			php${CORE_PHP}-session \
diff --git a/src/etc/inc/plugins.inc.d/dpinger.inc b/src/etc/inc/plugins.inc.d/dpinger.inc
index 048bd8a52..f12d5c06d 100644
--- a/src/etc/inc/plugins.inc.d/dpinger.inc
+++ b/src/etc/inc/plugins.inc.d/dpinger.inc
@@ -319,12 +319,17 @@ function dpinger_configure_do($verbose = false, $gwname = null, $bootup = false)
     }
 
     if (count(dpinger_services())) {
-        /* use a separate script to produce the monitor alerts which runs forever */
-        mwexecf(
-            '/usr/sbin/daemon -f -p %s /usr/local/opnsense/scripts/routes/gateway_watcher.php %s',
-            ['/var/run/gateway_watcher.pid', 'interface routes alarm'],
-            true
-        );
+        if (isvalidpid('/var/run/gateway_watcher.pid')) {
+            /* indicate that the configuration needs a reload */
+            killbypid('/var/run/gateway_watcher.pid', 'HUP');
+        } else {
+            /* use a separate script to produce the monitor alerts which runs forever */
+            mwexecf(
+                '/usr/sbin/daemon -f -p %s /usr/local/opnsense/scripts/routes/gateway_watcher.php %s',
+                ['/var/run/gateway_watcher.pid', 'interface routes alarm'],
+                true
+            );
+        }
     } else {
         killbypid('/var/run/gateway_watcher.pid');
     }
diff --git a/src/opnsense/scripts/routes/gateway_watcher.php b/src/opnsense/scripts/routes/gateway_watcher.php
index e67debbff..248650205 100755
--- a/src/opnsense/scripts/routes/gateway_watcher.php
+++ b/src/opnsense/scripts/routes/gateway_watcher.php
@@ -31,7 +31,18 @@ require_once 'config.inc';
 require_once 'util.inc';
 require_once 'interfaces.inc';
 
+function signalhandler($signal)
+{
+    global $config;
+
+    OPNsense\Core\Config::getInstance()->forceReload();
+    $config = parse_config();
+
+    syslog(LOG_NOTICE, 'Reloaded gateway watcher configuration on SIGHUP');
+}
+
 openlog('dpinger', LOG_DAEMON, LOG_LOCAL4);
+pcntl_signal(SIGHUP, 'signalhandler');
 
 $action = !empty($argv[1]) ? $argv[1] : null;
 
@@ -43,12 +54,10 @@ $mode = [];
 sleep($wait);
 
 while (1) {
-    $alarm = false;
-
-    OPNsense\Core\Config::getInstance()->forceReload();
-    $config = parse_config();
+    pcntl_signal_dispatch();
 
     $status = return_gateways_status();
+    $alarm = false;
 
     /* clear known gateways in first step to flush unknown in second step */
     $cleanup = $mode;