[gbsyncd] Graceful shutdown of syncd process in container gbsyncd (#16812)

Fix #16608. Need to gracefully shutdown syncd/gbsyncd individually.

files/scripts/gbsyncd.sh

@@ -19,7 +19,32 @@ function waitplatform() {
 }
 
 function stopplatform1() {
-    :
+    # Invoke platform specific pre shutdown routine.
+    PLATFORM=`$SONIC_DB_CLI CONFIG_DB hget 'DEVICE_METADATA|localhost' platform`
+    PLATFORM_PRE_SHUTDOWN="/usr/share/sonic/device/$PLATFORM/plugins/gbsyncd_request_pre_shutdown"
+    [ -f $PLATFORM_PRE_SHUTDOWN ] && \
+        /usr/bin/docker exec -i gbsyncd$DEV /usr/share/sonic/platform/plugins/gbsyncd_request_pre_shutdown --${TYPE}
+
+    debug "${TYPE} shutdown syncd process in container gbsyncd$DEV ..."
+    /usr/bin/docker exec -i gbsyncd$DEV /usr/bin/syncd_request_shutdown -g 1 -x /usr/share/sonic/hwsku/context_config.json --${TYPE}
+
+    # wait until syncd quits gracefully or force syncd to exit after
+    # waiting for 20 seconds
+    start_in_secs=${SECONDS}
+    end_in_secs=${SECONDS}
+    timer_threshold=20
+    while docker top gbsyncd$DEV | grep -q /usr/bin/syncd \
+            && [[ $((end_in_secs - start_in_secs)) -le $timer_threshold ]]; do
+        sleep 0.1
+        end_in_secs=${SECONDS}
+    done
+
+    if [[ $((end_in_secs - start_in_secs)) -gt $timer_threshold ]]; then
+        debug "syncd process in container gbsyncd$DEV did not exit gracefully"
+    fi
+
+    /usr/bin/docker exec -i gbsyncd$DEV /bin/sync
+    debug "Finished ${TYPE} shutdown syncd process in container gbsyncd$DEV ..."
 }
 
 function stopplatform2() {