diff --git a/src/Makefile.am b/src/Makefile.am
index 3467ebe7..cc4152b0 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -55,7 +55,7 @@ endif
 #endif
 
 if BUILD_FREEBSD
-freebsd = freebsd.c
+freebsd = freebsd.c diskio.c
 PTHREAD_LIBS =  -pthread
 endif
 
diff --git a/src/freebsd.c b/src/freebsd.c
index 9b9d76ea..6386dfd5 100644
--- a/src/freebsd.c
+++ b/src/freebsd.c
@@ -721,7 +721,7 @@ update_diskio()
 						diskio_stats[i].current_read = 0;
 						diskio_stats[i].current = diskio_stats[i].current_write;
 					}
-					if (writes < diskio_stats[i].last_write) {
+					if (dev->bytes[DEVSTAT_WRITE] < diskio_stats[i].last_write) {
 						diskio_stats[i].current_write = 0;
 						diskio_stats[i].current = diskio_stats[i].current_read;
 					}