K 10 svn:author V 5 markj K 8 svn:date V 27 2013-09-20T23:50:14.641442Z K 7 svn:log V 728 MFC r250953: The fasttrap provider cleans up probes asynchronously when a process with USDT probes exits. This was previously done with a callout; however, it is possible to sleep while holding the DTrace mutexes, so a panic will occur on INVARIANTS kernels if the callout handler can't immediately acquire one of these mutexes. This panic will be frequently triggered on systems where a USDT-enabled program (perl, for instance) is often run. This revision changes the fasttrap cleanup mechanism so that a dedicated thread is used instead of a callout. The old behaviour is otherwise preserved. MFC r252493: Be sure to destory the fasttrap cleanup mutex when unloading the fasttrap module. This should be MFCed with r250953. END