Commit Graph

170 Commits

Author SHA1 Message Date
Andriy Gapon
27b6c49726 add invpcid instruction to i386 dtrace disassembler tables
MFC after:	2 weeks
2016-04-29 15:45:22 +00:00
Mark Johnston
cd8bbc382d Add a kern.dtrace.err_verbose sysctl to control dtrace_err_verbose.
When this flag is turned on, DOF and DIF validation errors are printed to
the kernel message buffer. This is useful for debugging.

Also remove the debug.dtrace.debug sysctl, which has no effect.
2016-04-25 18:09:36 +00:00
Andriy Gapon
2d69831b85 lahf/sahf are supported on some amd64 processors
While the instructions were not included into the original instruction
set, their support can be indicated by a special feature bit.
For example:
  CPU: AMD Phenom(tm) II X4 955 Processor (3214.71-MHz K8-class CPU)
  ...
    AMD Features2=0x37ff<LAHF, ...>

Clang 3.8 uses lahf/sahf as a faster alternative to pushf/popf where
possible.

MFC after:	2 weeks
2016-04-22 13:44:12 +00:00
Mark Johnston
6c2806594b Make the second argument of dtrace_invop() a trapframe pointer.
Currently this argument is a pointer into the stack which is used by FBT
to fetch the first five probe arguments. On all non-x86 architectures it's
simply the trapframe address, so this change has no functional impact. On
amd64 it's a pointer into the trapframe such that stack[1 .. 5] gives the
first five argument registers, which are deliberately grouped together in
the amd64 trapframe definition.

A trapframe argument simplifies the invop handlers on !x86 and makes the
x86 FBT invop handler easier to understand. Moreover, it allows for invop
handlers that may want to modify the register set of the interrupted thread.
2016-04-17 23:08:47 +00:00
Mark Johnston
33b454938a Initialize SDT probes during SI_SUB_DTRACE_PROVIDER.
This is consistent with all other DTrace providers and ensures that
SDT probes are available for boot-time tracing.

MFC after:	2 weeks
2016-04-10 01:24:27 +00:00
Mark Johnston
e1e33ff912 Initialize DTrace hrtimer frequency during SI_SUB_CPU on i386 and amd64.
This allows the hrtimer to be used earlier during boot. This is required
for boot-time DTrace: anonymous enablings are created during
SI_SUB_DTRACE_ANON, which runs before APs are started. In particular,
the DTrace deadman timer requires that the hrtimer be functional.

MFC after:	2 weeks
2016-04-10 01:23:39 +00:00
Wojciech Macek
1c7c13aa0e Implement dtrace_getupcstack in ARM64
Allow using DTRACE for performance analysis of userspace
applications - the function call stack can be captured.
This is almost an exact copy of AMD64 solution.

Obtained from:         Semihalf
Sponsored by:          Cavium
Reviewed by:           emaste, gnn, jhibbits
Differential Revision: https://reviews.freebsd.org/D5779
2016-04-06 05:13:36 +00:00
Mark Johnston
48cc2d5e22 Remove unused variables dtrace_in_probe and dtrace_in_probe_addr. 2016-03-17 18:55:54 +00:00
Mark Johnston
9610c89750 Fix a couple of silly mistakes in r291962.
- Handle the case where no DOF helper is provided. This occurs with the
  currently-unused DTRACEHIOC_ADD ioctl.
- Fix some checks that prevented the loading DOF in the (non-default)
  lazyload mode.
2016-03-08 00:46:03 +00:00
Svatopluk Kraus
35a0bc1260 As <machine/vmparam.h> is included from <vm/vm_param.h>, there is no
need to include it explicitly when <vm/vm_param.h> is already included.

Suggested by:	alc
Reviewed by:	alc
Differential Revision:	https://reviews.freebsd.org/D5379
2016-02-22 09:08:04 +00:00
Michal Meloun
7a308c64b4 ARM: Rename remaining ARMv4 specific function in DTrace code.
I missed it in r295319.

Pointed by: tuexen
2016-02-06 11:16:15 +00:00
Andrew Turner
06ef48781d Be stricter on which functions we can probe with FBT. We now only check the
first instruction to see if it's either a pushm with lr, or a sub with sp.
The former is the common case, with the latter used with va_args.

This removes 12 probes. These are all hand-written assembly, with a few C
functions with no stack usage.

Submitted by:	Howard Su <howard0su@gmail.com>
Differential Revision:	https://reviews.freebsd.org/D4419
2015-12-23 17:54:19 +00:00
Mark Johnston
8ff6d9dd22 Support an arbitrary number of arguments to DTrace syscall probes.
Rather than pushing all eight possible arguments into dtrace_probe()'s
stack frame, make the syscall_args struct for the current syscall available
via the current thread. Using a custom getargval method for the systrace
provider, this allows any syscall argument to be fetched, even in kernels
that have modified the maximum number of system call arguments.

Sponsored by:	EMC / Isilon Storage Division
2015-12-17 00:00:27 +00:00
Mark Johnston
feea513564 Remove the unused systrace device file and fix style bugs.
MFC after:	1 week
2015-12-16 23:46:27 +00:00
Mark Johnston
6e0f204c3f Modify DTRACEHIOC_ADDDOF to copy the DOF section from the target process.
r281257 added support for lazyload mode by allowing dtrace(1) to register
a DOF section on behalf of a traced process. This was implemented by
having libdtrace copy the DOF section into a heap-allocated buffer and
passing its address to the ioctl handler. However, DTrace uses the DOF
section address as a lookup key in certain cases, so the ioctl handler
should be given the target process' DOF section address instead. This
change modifies the ADDDOF handler to copy the DOF section in from the
target process, rather than from dtrace(1).
2015-12-07 21:44:05 +00:00
Andrew Turner
5cde34a0ff Allow the artificial profile frames to be adjusted as needed by the user.
While here update for armv6 to a tested value.

Submitted by:	Howard Su <howard0su@gmail.com>
Reviewed by:	stat
Differential Revision:	https://reviews.freebsd.org/D4315
2015-12-05 10:00:01 +00:00
Andrew Turner
c218815337 Move the check to see if we are tracing a function with the DTrace Function
Boundary Trace to assembly to reduce the overhead of these checks.

Submitted by:	Howard Su <howard0su@gmail.com>
Relnotes:	Yes
Differential Revision:	https://reviews.freebsd.org/D4266
2015-12-05 09:32:36 +00:00
Mark Johnston
4d7296f9aa Fix a bug in the amd64 dtrace_getarg() implementation: when unwinding the
stack, take into account the copy of rsi pushed between the breakpoint
trapframe and the dtrace_invop frame. Prior to r287644, this was covered
by the fact that sizeof(struct amd64_frame) was 24 rather than 16.

Reported by:	smh
2015-11-19 05:33:15 +00:00
John Baldwin
2f99bcce1e Rename remaining linux32 symbols such as linux_sysent[] and
linux_syscallnames[] from linux_* to linux32_* to avoid conflicts with
linux64.ko.  While here, add support for linux64 binaries to systrace.
- Update NOPROTO entries in amd64/linux/syscalls.master to match the
  main table to fix systrace build.
- Add a special case for union l_semun arguments to the systrace
  generation.
- The systrace_linux32 module now only builds the systrace_linux32.ko.
  module on amd64.
- Add a new systrace_linux module that builds on both i386 and amd64.
  For i386 it builds the existing systrace_linux.ko.  For amd64 it
  builds a systrace_linux.ko for 64-bit binaries.

Reviewed by:	markj
Differential Revision:	https://reviews.freebsd.org/D3954
2015-10-22 21:28:20 +00:00
Andriy Gapon
a26cc6c081 sdt: static-ize couple of variables
MFC after:	11 days
2015-09-29 12:14:22 +00:00
Andriy Gapon
ab8d248801 sdt module does not seem to actually use any symbol from opensolaris module
MFC after:	11 days
2015-09-29 12:13:31 +00:00
Andriy Gapon
3bd9b9a600 std: it is important that func name is never an empty string
otherwise DTRACE_ANCHORED() returns false and that makes stack()
insert a bogus frame at the top.
For example:
dtrace -n 'test:dtrace_test::sdttest { stack(); }

This change is not really a solution, but just a work-around.
The real solution is to record the probe's call site and to use
that for resolving a function name.

PR:		195222
MFC after:	22 days
2015-09-29 12:02:23 +00:00
Andriy Gapon
09999d92b1 sdt: start checking version field when parsing probe definitions
This is an extra safety measure.

MFC after:	21 days
2015-09-29 11:58:21 +00:00
Andriy Gapon
c9d71814d5 dtrace_getarg: remove stray return statement on amd64, powerpc
MFC after:	10 days
2015-09-29 11:55:26 +00:00
Mark Johnston
1e954a7c63 Remove the arg0 field from struct amd64_frame. Its existence was a bug,
since on amd64 the first argument to a function is generally not on the
stack.

Revert an old DTrace bug fix to some code that assumed that
sizeof(struct amd64_frame) == 16.

Reviewed by:	jhb, kib
Sponsored by:	EMC / Isilon Storage Division
Differential Revision:	https://reviews.freebsd.org/D3255
2015-09-11 03:31:22 +00:00
Mark Johnston
1c9a705223 Remove a couple of unused fields from the FBT probe struct. 2015-08-03 17:39:36 +00:00
Mark Johnston
d258fd1d98 Remove checks for a NULL return value from M_WAITOK allocations. 2015-07-21 23:44:36 +00:00
Mark Johnston
32cd0147fa Implement the lockstat provider using SDT(9) instead of the custom provider
in lockstat.ko. This means that lockstat probes now have typed arguments and
will utilize SDT probe hot-patching support when it arrives.

Reviewed by:	gnn
Differential Revision:	https://reviews.freebsd.org/D2993
2015-07-19 22:14:09 +00:00
Mark Johnston
efe8b26b82 Modify lockstat_nsecs() to just return unless lockstat probes are actually
enabled. The cost of a timecounter read can be quite significant, and the
problem became more apparent after r284297, since that change resulted in
a call to lockstat_nsecs() for each acquisition of an rwlock read lock.

PR:		201642
Reviewed by:	avg
Tested by:	Jason Unovitch
MFC after:	3 days
Differential Revision:	https://reviews.freebsd.org/D3073
2015-07-18 00:22:00 +00:00
Konstantin Belousov
888e282ab4 When checking for the valid value of the frame pointer, verify that it
belongs to the kernel stack address range for the thread.  Right now,
code checks that new frame is not farther then KSTACK_PAGES pages from
the current frame, which allows the address to point past the top of
the stack.

Reviewed by:	andrew, emaste, markj
Differential revision:	https://reviews.freebsd.org/D3108
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
2015-07-16 19:40:18 +00:00
Konstantin Belousov
6fdfd88220 Use single instance of the identical INKERNEL() and PMC_IN_KERNEL()
macros on amd64 and i386.  Move the definition to machine/param.h.
kgdb defines INKERNEL() too, the conflict is resolved by renaming kgdb
version to PINKERNEL().

On i386, correct the lowest kernel address.  After the shared page was
introduced, USRSTACK no longer points to the last user address + 1 [*]

Submitted by:	Oliver Pinter [*]
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2015-07-02 14:37:21 +00:00
Ruslan Bukin
b78ee15e9f First cut of DTrace for AArch64.
Reviewed by:	andrew, emaste
Sponsored by:	ARM Limited
Differential Revision:	https://reviews.freebsd.org/D2738
2015-07-01 15:51:11 +00:00
Ruslan Bukin
0ff41755cd Add a central location for exclusion checks. We check
here if function is excluded from FBT instrumentation.

Reviewed by:	andrew, emaste, markj
Differential Revision:	https://reviews.freebsd.org/D2899
2015-07-01 14:09:59 +00:00
Ruslan Bukin
8bd0e17595 Don't re-define LOCORE when dtrace is built-in to the kernel. 2015-06-10 09:59:26 +00:00
Mark Johnston
11027ebcbb Remove unused references to calltrap.
MFC after:	3 days
2015-05-25 01:22:56 +00:00
Jung-uk Kim
fd90e2ed54 CALLOUT_MPSAFE has lost its meaning since r141428, i.e., for more than ten
years for head.  However, it is continuously misused as the mpsafe argument
for callout_init(9).  Deprecate the flag and clean up callout_init() calls
to make them more consistent.

Differential Revision:	https://reviews.freebsd.org/D2613
Reviewed by:	jhb
MFC after:	2 weeks
2015-05-22 17:05:21 +00:00
Mark Johnston
5a9f9cb38e Remove some commented-out upstream code for handling traps from usermode
DTrace probes. This handling is already done in trap() on i386 and amd64.
2015-05-10 22:27:48 +00:00
Robert Watson
a12df97ed2 Adjust PROF_ARTIFICIAL_FRAMES in the DTrace profile provider on ARM to
skip 10, rather than 9, frames.  This appears to work quite well in
practice on the BeagleBone Black, so remove a comment about the value
being bogus and replace it with a slightly less negative one.  However,
the number of frames to skip is quite sensitive to details of the timer
and interrupt handling paths, so this is necessarily fragile -- but no
more so than on x86.

Sponsored by:	DARPA, AFRL
2015-04-25 15:43:12 +00:00
Mark Johnston
8241ee3b2c Fix DTrace's panic() action.
It would previously call into some unfinished Solaris compatibility code and
return without actually calling panic(9). The compatibility code is
unneeded, however, so just remove it and have dtrace_panic() call vpanic(9)
directly.

Differential Revision:	https://reviews.freebsd.org/D2349
Reviewed by:	avg
MFC after:	2 weeks
Sponsored by:	EMC / Isilon Storage Division
2015-04-24 03:19:30 +00:00
Mark Johnston
67cf27b70f libdtrace: add support for lazyload mode.
Passing "-x lazyload" to dtrace -G during compilation causes dtrace(1) to
not link drti.o into the output object file, so the USDT probes are not created
during process startup. Instead, dtrace(1) will automatically discover and
create probes on the process' behalf when attaching.

Differential Revision:	https://reviews.freebsd.org/D2203
Reviewed by:		rpaulo
MFC after:		1 month
2015-04-08 02:36:37 +00:00
Mark Johnston
09a15aa38d Import a missing piece of commit b8fac8e162eda7e98d from illumos-gate.
This adds an upper bound, dtrace_ustackdepth_max, to the number of frames
traversed when computing the userland stack depth. Some programs - notably
firefox - are otherwise able to trigger an infinite loop in
dtrace_getustack_common(), causing a panic.

MFC after:	1 week
2015-03-30 03:55:51 +00:00
Robert Watson
9dcce6e267 Now that DTrace stack traces handle exception frames better, skip fewer
stack frames for FBT 'entry' probes on ARM.

MFC after:	3 days
Sponsored by:	DARPA, AFRL
2015-03-15 15:19:02 +00:00
Robert Watson
2a1d3dee4f On ARM, unlike some other architectures, saved $pc values from in-kernel
traps do appear in the regular call stack, rather than only in a special
trap frame, so we don't need to inject the trap-frame $pc into a returned
stack trace in DTrace.

MFC after:	3 days
Sponsored by:	DARPA, AFRL
2015-03-15 15:17:34 +00:00
Robert Watson
808d83b01a Replace the completely arbitrary '3' with '9' for the number of frames to
skip using the DTrace 'profile' provider on ARM.  This causes stack traces
to skip various driver-and callout-related things as they do on x86, where
the likewise arbitrary values are '6' (32-bit) and '10' (64-bit) for
similar sorts of reasons.

MFC after:	3 days
Sponsored by:	DARPA, AFRL
2015-03-15 14:12:40 +00:00
George V. Neville-Neil
a340dc5348 Add support for walltimestamp to DTrace on ARM. 2015-03-07 04:38:25 +00:00
Andrew Turner
be9bc81174 dtrace_cas32 and dtrace_casptr should retrn the data loaded from target
not the new value.

Sponsored by:	ABT Systems Ltd
2015-03-05 18:03:42 +00:00
Andrew Turner
4a8169d97b Add the MD parts of dtrace needed to use fbt on ARM. For this we need to
emulate the instructions used in function entry and exit.

For function entry ARM will use a push instruction to push up to 16
registers to the stack. While we don't expect all 16 to be used we need to
handle any combination the compiler may generate, even if it doesn't make
sense (e.g. pushing the program counter).

On function return we will either have a pop or branch instruction. The
former is similar to the push instruction, but with care to make sure we
update the stack pointer and program counter correctly in the cases they
are either in the list of registers or not. For branch we need to take the
24-bit offset, sign-extend it, and add that number of 4-byte words to the
program counter. Care needs to be taken as, due to historical reasons, the
address the branch is relative to is not the current instruction, but 8
bytes later.

This allows us to use the following probes on ARM boards:
  dtrace -n 'fbt::malloc:entry { stack() }'
and
  dtrace -n 'fbt:🆓return { stack() }'

Differential Revision:	https://reviews.freebsd.org/D2007
Reviewed by:	gnn, rpaulo
Sponsored by:	ABT Systems Ltd
2015-03-05 17:55:31 +00:00
Nathan Whitehorn
4c790d26d1 Fix build after unifying DAR/DEAR storage in trap frame. 2015-03-05 17:02:22 +00:00
Robert Watson
ca162c0888 Don't all DTrace's FBT on ARM to instrument undefinedinstruction(), as
this would lead to DTrace reentrance.

Sponsored by:	DARPA, AFRL
2015-03-05 07:40:41 +00:00
Andrew Turner
2b6af94bc8 Fix the dtrace ARM atomic compare-and-set functions. These functions are
expected to return the data in the memory location pointed at by target
after the operation. The FreeBSD atomic functions previously used return
either 0 or 1 to indicate if the comparison succeeded or not respectively.

With this change these functions only support ARMv6 and later are supported
by these functions.

Sponsored by:	ABT Systems Ltd
2015-03-01 10:04:14 +00:00