collectd: SQM collect data from some qdiscs

Add a script that can collect data from mq (multi queue) and cake
qdiscs.

Script is reliant on collectd's 'exec' module.

Signed-off-by: Kevin Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>

utils/collectd/Makefile

@@ -362,6 +362,32 @@ define BuildPlugin
 
 endef
 
+define BuildScriptPlugin
+  PKG_CONFIG_DEPENDS+= CONFIG_PACKAGE_collectd-mod-$(1)
+
+  define Package/collectd-mod-$(1)
+  $$(call Package/collectd/Default)
+    TITLE:=$(2) plugin
+    DEPENDS:= $(4)
+  endef
+
+  define Package/collectd-mod-$(1)/install
+	$(INSTALL_DIR) $$(1)/usr/libexec/collectd
+	for m in $(3); do \
+		${INSTALL_BIN} \
+			./files/exec-scripts/$$$$$$$${m}.sh $$(1)/usr/libexec/collectd/ ; \
+	done
+	if [ -f ./files/usr/share/collectd/plugin/$(1).json ]; then \
+		$(INSTALL_DIR) $$(1)/usr/share/collectd/plugin ; \
+		$(INSTALL_DATA) ./files/usr/share/collectd/plugin/$(1).json \
+			$$(1)/usr/share/collectd/plugin/$(1).json ; \
+	fi
+  endef
+
+  $$(eval $$(call BuildPackage,collectd-mod-$(1)))
+
+endef
+
 $(eval $(call BuildPackage,collectd))
 
 #$(eval $(call BuildPlugin,NAME,DESCRIPTION,FILES,DEPENDENCIES))
@@ -434,3 +460,5 @@ $(eval $(call BuildPlugin,vmem,virtual memory usage input,vmem,))
 $(eval $(call BuildPlugin,wireless,wireless status input,wireless,))
 $(eval $(call BuildPlugin,write-graphite,Carbon/Graphite output,write_graphite,+PACKAGE_collectd-mod-write-graphite:libpthread))
 $(eval $(call BuildPlugin,write-http,HTTP POST output,write_http,+PACKAGE_collectd-mod-write-http:libcurl))
+
+$(eval $(call BuildScriptPlugin,sqm,SQM/qdisc collection,sqm_collectd,+PACKAGE_collectd-mod-sqm:collectd-mod-exec))

utils/collectd/files/collectd.init

@@ -11,6 +11,11 @@ NICEPRIO=5
 
 CONFIG_STRING=""
 
+[ -d /usr/libexec/collectd ] && {
+	find /usr/libexec/collectd ! -perm 0500 -exec chmod 0500 '{}' '+'
+	find /usr/libexec/collectd ! \( -user nobody -a -group nogroup \) -exec chown nobody:nogroup '{}' '+'
+}
+
 process_exec() {
 	printf "<Plugin exec>\n" >> "$COLLECTD_CONF"
 	config_foreach process_exec_sections exec_input "Exec"

utils/collectd/files/exec-scripts/sqm_collectd.sh

@@ -0,0 +1,106 @@
+#!/bin/sh
+
+. /usr/share/libubox/jshn.sh
+
+HOSTNAME="${COLLECTD_HOSTNAME:-localhost}"
+INTERVAL="${COLLECTD_INTERVAL:-60.000}"
+
+handle_cake() {
+	local ifc ifr tin i
+
+	ifc="$1"
+	ifr="${ifc//./_}"
+
+	# Overall
+	json_get_vars bytes packets drops backlog qlen
+
+	# Options
+	json_select options
+	json_get_vars bandwidth diffserv
+	json_select ".."
+
+	echo "PUTVAL \"$HOSTNAME/sqm-$ifc/qdisc_bytes\" interval=$INTERVAL N:$bytes"
+	echo "PUTVAL \"$HOSTNAME/sqm-$ifc/qdisc_drops\" interval=$INTERVAL N:$drops"
+	echo "PUTVAL \"$HOSTNAME/sqm-$ifc/qdisc_backlog\" interval=$INTERVAL N:$backlog"
+
+	# ash doesn't have arrays so prepare to get a little creative
+	case "$diffserv" in
+		diffserv3 | diffserv4) tns="BKBEVIVO"
+			;;
+		*) tns="T0T1T2T3T4T5T6T7"
+			;;
+	esac
+
+	# Tins
+	# Flows & delays indicate the state as of the last packet that flowed through, so they appear to get stuck.
+	# Discard the results from a stuck tin.
+	json_get_keys tins tins
+	json_select tins
+	i=0
+	for tin in $tins; do
+		json_select "$tin"
+		json_get_vars threshold_rate sent_bytes sent_packets backlog_bytes target_us peak_delay_us avg_delay_us base_delay_us drops ecn_mark ack_drops sparse_flows bulk_flows unresponsive_flows
+
+		eval osp="\$osp${ifr}t${i}"
+		if  [ "$osp" ] && [ "$osp" -eq "$sent_packets" ] ; then
+			peak_delay_us=0; avg_delay_us=0; base_delay_us=0
+			sparse_flows=0; bulk_flows=0; unresponsive_flows=0
+		else
+			eval "osp${ifr}t${i}=$sent_packets"
+		fi
+
+		tn=${tns:$((i<<1)):2}
+
+		echo "PUTVAL \"$HOSTNAME/sqmcake-$ifc/qdisct_bytes-$tn\" interval=$INTERVAL N:$sent_bytes"
+		echo "PUTVAL \"$HOSTNAME/sqmcake-$ifc/qdisct_thres-$tn\" interval=$INTERVAL N:$threshold_rate"
+		echo "PUTVAL \"$HOSTNAME/sqmcake-$ifc/qdisct_drops-$tn\" interval=$INTERVAL N:$drops:$ecn_mark:$ack_drops"
+		echo "PUTVAL \"$HOSTNAME/sqmcake-$ifc/qdisct_backlog-$tn\" interval=$INTERVAL N:$backlog_bytes"
+		echo "PUTVAL \"$HOSTNAME/sqmcake-$ifc/qdisct_flows-$tn\" interval=$INTERVAL N:$sparse_flows:$bulk_flows:$unresponsive_flows"
+		echo "PUTVAL \"$HOSTNAME/sqmcake-$ifc/qdisct_latencyus-$tn\" interval=$INTERVAL N:$target_us:$peak_delay_us:$avg_delay_us:$base_delay_us"
+
+		json_select ..
+		i=$((i+1))
+	done
+	json_select ..
+}
+
+handle_mq() {
+	ifc="$1"
+
+	# Overall
+	json_get_vars bytes drops backlog
+
+	echo "PUTVAL \"$HOSTNAME/sqm-$ifc/qdisc_bytes\" interval=$INTERVAL N:$bytes"
+	echo "PUTVAL \"$HOSTNAME/sqm-$ifc/qdisc_drops\" interval=$INTERVAL N:$drops"
+	echo "PUTVAL \"$HOSTNAME/sqm-$ifc/qdisc_backlog\" interval=$INTERVAL N:$backlog"
+}
+
+process_qdisc() {
+	local ifc jsn
+
+	ifc="$1"
+	jsn=$(tc -s -j qdisc show dev "$ifc")
+	# strip leading & trailing []
+	jsn="${jsn#[}" ; jsn="${jsn%]}"
+
+	json_load "${jsn}"
+	json_get_var qdisc kind
+
+	case "$qdisc" in
+		cake) handle_cake "$ifc"
+		;;
+		mq) handle_mq "$ifc"
+		;;
+
+		*) echo "Unknown qdisc type" 1>&2
+		;;
+	esac
+	json_cleanup
+}
+
+while true ; do
+	for ifc in "$@" ; do
+		process_qdisc "$ifc"
+	done
+	sleep "${INTERVAL%.000}"
+done

utils/collectd/patches/910-add-cake-qdisc-types.patch

@@ -0,0 +1,20 @@
+--- a/src/types.db
++++ b/src/types.db
+@@ -303,6 +303,17 @@ vs_memory               value:GAUGE:0:92
+ vs_processes            value:GAUGE:0:65535
+ vs_threads              value:GAUGE:0:65535
+ 
++qdisc_bytes             value:DERIVE:0:U
++qdisc_drops             value:DERIVE:0:U
++qdisc_backlog           value:GAUGE:0:U
++
++qdisct_bytes            value:DERIVE:0:U
++qdisct_thres            value:GAUGE:0:U
++qdisct_drops            drops:DERIVE:0:U, ecn:DERIVE:0:U, ack:DERIVE:0:U
++qdisct_backlog          value:GAUGE:0:U
++qdisct_latencyus	tg:GAUGE:0:U, pk:GAUGE:0:U, av:GAUGE:0:U, sp:GAUGE:0:U
++qdisct_flows		sp:GAUGE:0:U, bu:GAUGE:0:U, un:GAUGE:0:U
++
+ #
+ # Legacy types
+ # (required for the v5 upgrade target)