freebsd with flexible iflib nic queues
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Mark Johnston 8776669b53 FreeBSD's DTrace implementation has a few problems with respect to handling
probes declared in a kernel module when that module is unloaded. In
particular,

* Unloading a module with active SDT probes will cause a panic. [1]
* A module's (FBT/SDT) probes aren't destroyed when the module is unloaded;
  trying to use them after the fact will generally cause a panic.

This change fixes both problems by porting the DTrace module load/unload
handlers from illumos and registering them with the corresponding
EVENTHANDLER(9) handlers. This allows the DTrace framework to destroy all
probes defined in a module when that module is unloaded, and to prevent a
module unload from proceeding if some of its probes are active. The latter
problem has already been fixed for FBT probes by checking lf->nenabled in
kern_kldunload(), but moving the check into the DTrace framework generalizes
it to all kernel providers and also fixes a race in the current
implementation (since a probe may be activated between the check and the
call to linker_file_unload()).

Additionally, the SDT implementation has been reworked to define SDT
providers/probes/argtypes in linker sets rather than using SYSINIT/SYSUNINIT
to create and destroy SDT probes when a module is loaded or unloaded. This
simplifies things quite a bit since it means that pretty much all of the SDT
code can live in sdt.ko, and since it becomes easier to integrate SDT with
the DTrace framework. Furthermore, this allows FreeBSD to be quite flexible
in that SDT providers spanning multiple modules can be created on the fly
when a module is loaded; at the moment it looks like illumos' SDT
implementation requires all SDT probes to be statically defined in a single
kernel table.

PR:		166927, 166926, 166928
Reported by:	davide [1]
Reviewed by:	avg, trociny (earlier version)
MFC after:	1 month
2013-08-13 03:10:39 +00:00
bin Add -c flag to pgrep(1) and pkill(1), to match login classes. 2013-08-09 08:38:51 +00:00
cddl Load the dtraceall module if /dev/dtrace/dtrace doesn't exist. 2013-08-10 23:17:09 +00:00
contrib Temporarily revert sendmail 8.14.7 change to getipnodebyname() flags to 2013-08-12 17:22:39 +00:00
crypto MFV r254106 (OpenSSL bugfix for RT #2984): 2013-08-08 22:29:35 +00:00
etc Add empty zones for Shared Address Space (RFC 6598) 2013-08-09 07:57:04 +00:00
games Remove a reference to instant-server which has been removed from the 2013-03-21 12:42:25 +00:00
gnu Add FreeBSD 9.2 to mdoc.local. 2013-08-11 18:05:20 +00:00
include Add mkostemp() and mkostemps(). 2013-08-09 17:24:23 +00:00
kerberos5 Fix the getpwnam_r() call in the pname_to_uid() kerberos library function so 2013-05-02 12:52:49 +00:00
lib db/hash: Use O_CLOEXEC instead of separate fcntl() call. 2013-08-11 15:38:48 +00:00
libexec Revert r253748,253749 2013-07-28 18:44:17 +00:00
release Fix the bootable CD: 2013-08-03 20:14:29 +00:00
rescue - Trim an unused and bogus Makefile for mount_smbfs. 2013-06-28 21:00:08 +00:00
sbin Change <sys/diskpc98.h> to not redefine the same symbols that are 2013-08-07 00:00:48 +00:00
secure Remove references to MK_IDEA. 2013-04-27 05:44:39 +00:00
share Add event handlers for module load and unload events. The load handlers are 2013-08-13 03:07:49 +00:00
sys FreeBSD's DTrace implementation has a few problems with respect to handling 2013-08-13 03:10:39 +00:00
tools Fix some signed comparison compile warnings. 2013-08-12 09:15:33 +00:00
usr.bin Make check for unknown login class actually work. Previously, using the "-c" option 2013-08-12 21:01:01 +00:00
usr.sbin Make sure bootonly.iso for -BETAs and -RCs use the releases/ 2013-08-13 02:31:46 +00:00
COPYRIGHT Happy New Year 2013! 2012-12-31 11:22:55 +00:00
LOCKS Test commit to make sure commit mail works after moving the server. 2012-12-29 16:03:23 +00:00
MAINTAINERS Add myself as maintainer for nvme(4), nvd(4) and nvmecontrol(8). 2013-07-31 18:18:02 +00:00
Makefile Fix bug in universe where if upgrade_checks wants a new make, 2013-07-24 17:55:08 +00:00
Makefile.inc1 Update nvi-1.79 to 2.1.1-4334a8297f 2013-08-11 20:03:12 +00:00
ObsoleteFiles.inc In r227839, when removing libkvm dependency on procfs(5), 2013-07-10 19:44:43 +00:00
README Vendor import of OpenSSH 6.2p1. 2013-03-22 11:19:48 +00:00
UPDATING opensolaris code: translate INVARIANTS to DEBUG and ZFS_DEBUG 2013-08-06 15:51:56 +00:00

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