1
0
mirror of https://git.FreeBSD.org/src.git synced 2024-12-20 11:11:24 +00:00
freebsd/sys/cddl
Ryan Stone 9742410797 Instead of only iterating over the set of known SDT probes when sdt.ko is
loaded and unloaded, also have sdt.ko register callbacks with kern_sdt.c
that will be called when a newly loaded KLD module adds more probes or
a module with probes is unloaded.

This fixes two issues: first, if a module with SDT probes was loaded after
sdt.ko was loaded, those new probes would not be available in DTrace.
Second, if a module with SDT probes was unloaded while sdt.ko was loaded,
the kernel would panic the next time DTrace had cause to try and do
anything with the no-longer-existent probes.

This makes it possible to create SDT probes in KLD modules, although there
are still two caveats: first, any SDT probes in a KLD module must be part
of a DTrace provider that is defined in that module.  At present DTrace
only destroys probes when the provider is destroyed, so you can still
panic the system if a KLD module creates new probes in a provider from a
different module(including the kernel) and then unload the the first module.

Second, the system will panic if you unload a module containing SDT probes
while there is an active D script that has enabled those probes.

MFC after:	1 month
2012-03-27 15:07:43 +00:00
..
boot/zfs - Correctly read gang header from raidz. 2011-10-20 15:42:38 +00:00
compat/opensolaris Fix found places where uio_resid is truncated to int. 2012-02-21 01:05:12 +00:00
contrib/opensolaris Add MIPS support to cddl/contrib part: 2012-03-24 04:52:18 +00:00
dev Instead of only iterating over the set of known SDT probes when sdt.ko is 2012-03-27 15:07:43 +00:00