freebsd-dev/sys/cddl/contrib/opensolaris/uts/intel
Mark Johnston 380344a7af Fix fasttrap tracepoint locking.
Upstream, tracepoints are protected by per-CPU mutexes. An unlinked
tracepoint may be freed once all the tracepoint mutexes have been acquired
and released - this is done in fasttrap_mod_barrier(). This mechanism was
not properly ported: in some places, the proc lock is used in place of a
tracepoint lock, and in others the locking is omitted entirely. This change
implements tracepoint locking with an rmlock, where the read lock is used
in fasttrap probe context. As a side effect, this fixes a recursion on the
proc lock when the raise action is used from a userland probe.

MFC after:	1 month
2016-03-08 00:43:03 +00:00
..
dtrace Fix fasttrap tracepoint locking. 2016-03-08 00:43:03 +00:00
sys