Commit Graph

170 Commits

Author SHA1 Message Date
rpaulo
0a04223ce6 Make the /dev/dtrace/helper node have the mode 0660. This allows
programs that refuse to run as root (pgsql) to install probes when their
user is part of the wheel group.

Sponsored by:	The FreeBSD Foundation
> Description of fields to fill in above:                     76 columns --|
> PR:            If a GNATS PR is affected by the change.
> Submitted by:  If someone else sent in the change.
> Reviewed by:   If someone else reviewed your modification.
> Approved by:   If you needed approval for this commit.
> Obtained from: If the change is from a third party.
> MFC after:     N [day[s]|week[s]|month[s]].  Request a reminder email.
> Security:      Vulnerability reference (one per line) or description.
> Empty fields above will be automatically removed.

M    dev/dtrace/dtrace_load.c
2010-09-01 12:08:32 +00:00
rpaulo
9760737bfb Destroy the helper device when unloading.
Sponsored by:	The FreeBSD Foundation
2010-08-22 11:05:37 +00:00
rpaulo
ed2c978b97 Add more compatibility structure members needed by the upcoming fasttrap
DTrace device.

Sponsored by:	The FreeBSD Foundation
2010-08-22 11:04:43 +00:00
rpaulo
2b32a31ca3 Kernel DTrace support for:
o uregs  (sson@)
o ustack (sson@)
o /dev/dtrace/helper device (needed for USDT probes)

The work done by me was:
Sponsored by:	The FreeBSD Foundation
2010-08-22 10:53:32 +00:00
rpaulo
3a636008c7 Add a function compatibility function dtrace_instr_size_isa() that on
FreeBSD does the same as dtrace_dis_isize().

Sponsored by:	The FreeBSD Foundation
2010-08-22 10:40:15 +00:00
jhb
9b74a62d73 Update several places that iterate over CPUs to use CPU_FOREACH(). 2010-06-11 18:46:34 +00:00
kib
4208ccbe79 Reorganize syscall entry and leave handling.
Extend struct sysvec with three new elements:
sv_fetch_syscall_args - the method to fetch syscall arguments from
  usermode into struct syscall_args. The structure is machine-depended
  (this might be reconsidered after all architectures are converted).
sv_set_syscall_retval - the method to set a return value for usermode
  from the syscall. It is a generalization of
  cpu_set_syscall_retval(9) to allow ABIs to override the way to set a
  return value.
sv_syscallnames - the table of syscall names.

Use sv_set_syscall_retval in kern_sigsuspend() instead of hardcoding
the call to cpu_set_syscall_retval().

The new functions syscallenter(9) and syscallret(9) are provided that
use sv_*syscall* pointers and contain the common repeated code from
the syscall() implementations for the architecture-specific syscall
trap handlers.

Syscallenter() fetches arguments, calls syscall implementation from
ABI sysent table, and set up return frame. The end of syscall
bookkeeping is done by syscallret().

Take advantage of single place for MI syscall handling code and
implement ptrace_lwpinfo pl_flags PL_FLAG_SCE, PL_FLAG_SCX and
PL_FLAG_EXEC. The SCE and SCX flags notify the debugger that the
thread is stopped at syscall entry or return point respectively.  The
EXEC flag augments SCX and notifies debugger that the process address
space was changed by one of exec(2)-family syscalls.

The i386, amd64, sparc64, sun4v, powerpc and ia64 syscall()s are
changed to use syscallenter()/syscallret(). MIPS and arm are not
converted and use the mostly unchanged syscall() implementation.

Reviewed by:	jhb, marcel, marius, nwhitehorn, stas
Tested by:	marcel (ia64), marius (sparc64), nwhitehorn (powerpc),
	stas (mips)
MFC after:	1 month
2010-05-23 18:32:02 +00:00
rpaulo
7a84f3701d Rename the cyclic global variable lapic_cyclic_clock_func to just
cyclic_clock_func. This will make more sense when we start developing non
x86 cyclic version.
2010-04-20 17:03:30 +00:00
rpaulo
4eb7b21df0 The amd64 version of the cyclic dtrace module is a verbatim copy of the
i386 version, so instead having a copy of the same file, use Makefile
foo to include the i386 version on amd64.
2010-04-20 16:30:17 +00:00
avg
b898b874c6 dtrace_gethrtime: improve scaling of TSC ticks to nanoseconds
Currently dtrace_gethrtime uses formula similar to the following for
converting TSC ticks to nanoseconds:
rdtsc() * 10^9 / tsc_freq
The dividend overflows 64-bit type and wraps-around every 2^64/10^9 =
18446744073 ticks which is just a few seconds on modern machines.

Now we instead use precalculated scaling factor of
10^9*2^N/tsc_freq < 2^32 and perform TSC value multiplication separately
for each 32-bit half.  This allows to avoid overflow of the dividend
described above.
The idea is taken from OpenSolaris.
This has an added feature of always scaling TSC with invariant value
regardless of TSC frequency changes. Thus the timestamps will not be
accurate if TSC actually changes, but they are always proportional to
TSC ticks and thus monotonic. This should be much better than current
formula which produces wildly different non-monotonic results on when
tsc_freq changes.

Also drop write-only 'cp' variable from amd64 dtrace_gethrtime_init()
to make it identical to the i386 twin.

PR:		kern/127441
Tested by:	Thomas Backman <serenity@exscape.org>
Reviewed by:	jhb
Discussed with:	current@, bde, gnn
Silence from:	jb
Approved by:	re (gnn)
MFC after:	1 week
2009-07-15 17:07:39 +00:00
avg
296f644406 dtrace/amd64: fix virtual address checks
On amd64 KERNBASE/kernbase does not mean start of kernel memory.
This should fix a KASSERT panic in dtrace_copycheck when copyin*()
is used in D program.
Also make checks for user memory a bit stricter.

Reported by:	Thomas Backman <serenity@exscape.org>
Submitted by:	wxs (kaddr part)
Tested by:	Thomas Backman (prototype), wxs
Reviewed by:	alc (concept), jhb, current@
Aprroved by:	jb (concept)
MFC after:	2 weeks
PR:		kern/134408
2009-06-24 16:03:57 +00:00
sson
c0d5996eb6 Add the OpenSolaris dtrace lockstat provider. The lockstat provider
adds probes for mutexes, reader/writer and shared/exclusive locks to
gather contention statistics and other locking information for
dtrace scripts, the lockstat(1M) command and other potential
consumers.

Reviewed by:	attilio jhb jb
Approved by:	gnn (mentor)
2009-05-26 20:28:22 +00:00
rwatson
e610f292c5 Move dtnfsclient.c in the cddl tree to nfs_kdtrace.c in the nfsclient
directory, since it's under a BSD license, and this keeps NFS internals-
aware tracing parts close to NFS.

MFC after:	1 month
Suggested by:	jhb
2009-03-25 17:47:22 +00:00
rwatson
f0f3719742 Add DTrace probes to the NFS access and attribute caches. Access cache
events are:

  nfsclient:accesscache:flush:done
  nfsclient:accesscache:get:hit
  nfsclient:accesscache:get:miss
  nfsclient:accesscache:load:done

They pass the vnode, uid, and requested or loaded access mode (if any);
the load event may also report a load error if the RPC fails.

The attribute cache events are:

  nfsclient:attrcache:flush:done
  nfsclient:attrcache:get:hit
  nfsclient:attrcache:get:miss
  nfsclient:attrcache:load:done

They pass the vnode, optionally the vattr if one is present (hit or load),
and in the case of a load event, also a possible RPC error.

MFC after:	1 month
Sponsored by:	Google, Inc.
2009-03-24 17:14:34 +00:00
rwatson
c0055de891 Add dtnfsclient, a first cut at an NFSv2/v3 client reuest DTrace
provider.  The NFS client exposes 'start' and 'done' probes for NFSv2
and NFSv3 RPCs when using the new RPC implementation, passing in the
vnode, mbuf chain, credential, and NFSv2 or NFSv3 procedure number.
For 'done' probes, the error number is also available.

Probes are named in the following way:

  ...
  nfsclient:nfs2:write:start
  nfsclient:nfs2:write:done
  ...
  nfsclient:nfs3:access:start
  nfsclient:nfs3:access:done
  ...

Access to the unmarshalled arguments is not easily available at this
point in the stack, but the passed probe arguments are sufficient to
to a lot of interesting things in practice.  Technically, these probes
may cover multiple RPC retransmits, and even transactions if the
transaction ID change as a result of authentication failure or a
jukebox error from the server, but usefully capture the intent of a
single NFS request, such as access, getattr, write, etc.

Typical use might involve profiling RPC latency by system call, number
of RPCs, how often a getattr leads to a call to access, when failed
access control checks occur, etc.  More detailed RPC information might
best be provided by adding a krpc provider.  It would also be useful
to add NFS client probes for events such as the access cache or
attribute cache satisfying requests without an RPC.

Sponsored by:	Google, Inc.
MFC after:	1 month
2009-03-22 22:07:52 +00:00
ganbold
2ba03c3595 Remove unused variable.
Found with:     Coverity Prevent(tm)
CID: 3669,3671

Approved by: jb
2008-11-25 19:25:54 +00:00
rodrigc
8cd2060f99 Merge latest DTrace changes from Perforce. 2008-11-05 19:39:11 +00:00
ed
4212d51a7d Remove unit2minor() use from kernel code.
When I changed kern_conf.c three months ago I made device unit numbers
equal to (unneeded) device minor numbers. We used to require
bitshifting, because there were eight bits in the middle that were
reserved for a device major number. Not very long after I turned
dev2unit(), minor(), unit2minor() and minor2unit() into macro's.
The unit2minor() and minor2unit() macro's were no-ops.

We'd better not remove these four macro's from the kernel, because there
is a lot of (external) code that may still depend on them. For now it's
harmless to remove all invocations of unit2minor() and minor2unit().

Reviewed by:	kib
2008-09-26 14:19:52 +00:00
jb
a1fed4f2cd The cyclic timer device. This is a cut down version of the one in
OpenSolaris. We don't have the lock levels that they do, so this is just
hooked into clock interrupts.
2008-05-23 22:21:58 +00:00
jb
be12e1a504 Custom DTrace kernel module files plus FreeBSD-specific DTrace providers. 2008-05-23 05:59:42 +00:00