It's no dtrace, but check out systemtap "stap". It provides a lot of similar functionality on modern linux. It can actually use existing dtrace probe points if

It's no dtrace, but check out systemtap "stap". It provides a lot of similar functionality on modern linux. It can actually use existing dtrace probe points if you have a binary like mysqld. The ability to follow call graphs, and insert arbitrary logic, is amazing for chasing down system issues.