This is an update of @davepacheco's patch in #3617 that enables DTrace probes on OSX and adds more arguments to some of the probes to accomodate broken DTrace implementations
build: allow building with dtrace on osx
dtrace: pass more arguments to probes
OSX and other DTrace implementations don't support dereferencing
structs in probes. To accomodate that pass members from the struct as
arguments so that DTrace is useful on those systems.
+1! Thanks for doing this.
Landed in fe7440c and 7634069.