145 Commits

Author SHA1 Message Date
markj
b30bc0e211 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
markj
dcbb0d9c3f Remove a couple of unused fields from the FBT probe struct. 2015-08-03 17:39:36 +00:00
markj
aad6d5bfac Remove checks for a NULL return value from M_WAITOK allocations. 2015-07-21 23:44:36 +00:00
markj
fb4cb70b7d 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
markj
90a3119284 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
kib
67db66d5ea 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
kib
77205a0535 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
br
70d4d5a42d 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
br
e45cf9cd75 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
br
ab3ad78145 Don't re-define LOCORE when dtrace is built-in to the kernel. 2015-06-10 09:59:26 +00:00
markj
6928f32018 Remove unused references to calltrap.
MFC after:	3 days
2015-05-25 01:22:56 +00:00
jkim
318c4f97e6 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
markj
6ede9cbbef 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
rwatson
ed8c3c1f90 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
markj
9385b9197d 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
markj
1d6ffde4f4 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
markj
acaed6413c 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
rwatson
9f48720b49 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
rwatson
26e3e9bb99 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
rwatson
ec1dafc898 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
gnn
c531c598ba Add support for walltimestamp to DTrace on ARM. 2015-03-07 04:38:25 +00:00
andrew
43cb9d5cd8 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
ff8a1038b7 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
nwhitehorn
048b34a391 Fix build after unifying DAR/DEAR storage in trap frame. 2015-03-05 17:02:22 +00:00
rwatson
d81f712ba9 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
f4b588d2fc 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
andrew
c560f15fa8 Use the ARM unwinder with dtrace to extract the stack when asked. With this
dtrace is able to display a stack trace similar to the one below.

# dtrace -p 603 -n 'tcp:kernel::receive { stack(); }'
  0     70                         :receive
              kernel`ip_input+0x140
              kernel`netisr_dispatch_src+0xb8
              kernel`ether_demux+0x1c4
              kernel`ether_nh_input+0x3a8
              kernel`netisr_dispatch_src+0xb8
              kernel`ether_input+0x60
              kernel`cpsw_intr_rx+0xac
              kernel`intr_event_execute_handlers+0x128
              kernel`ithread_loop+0xb4
              kernel`fork_exit+0x84
              kernel`swi_exit
              kernel`swi_exit

Tested by:	gnn
Sponsored by:	ABT Systems Ltd
2015-02-19 12:20:21 +00:00
gnn
909002dc4f Clean up machine dependent code for DTrace on ARM.
Submitted by:	markj
2015-02-11 17:27:37 +00:00
gnn
b9be305241 Initial version of DTrace on ARM32.
Submitted by:	Howard Su based on work by Oleksandr Tymoshenko
Reviewed by:	ian, andrew, rpaulo, markj
2015-02-10 19:41:30 +00:00
pfg
8afbe75ac6 MFV r266993:
4469 DTrace helper tracing should be dynamic

Reference:
https://illumos.org/issues/4469

Obtained from:	Illumos
Phabric:	D1551
Reviewed by:	markj
MFC after:	2 weeks
2015-02-03 19:39:53 +00:00
smh
55c26d898b Mechanically convert cddl sun #ifdef's to illumos
Since the upstream for cddl code is now illumos not sun, mechanically
convert all sun #ifdef's to illumos #ifdef's which have been used in all
newer code for some time.

Also do a manual pass to correct the use if #ifdef comments as per style(9)
as well as few uses of #if defined(__FreeBSD__) vs #ifndef illumos.

MFC after:	1 month
Sponsored by:	Multiplay
2015-01-17 14:44:59 +00:00
markj
7ea63e4fb4 Restore the trap type argument to the DTrace trap hook, removed in r268600.
It's redundant at the moment since it can be obtained from the trapframe
on the architectures where DTrace is supported, but this won't be the case
with ARM.
2014-12-23 15:38:19 +00:00
avg
15bfe2d262 remove opensolaris cyclic code, replace with high-precision callouts
In the old days callout(9) had 1 tick precision and that was inadequate
for some uses, e.g. DTrace profile module, so we had to emulate cyclic
API and behavior.  Now we can directly use callout(9) in the very few
places where cyclic was used.

Differential Revision:	https://reviews.freebsd.org/D1161
Reviewed by:	gnn, jhb, markj
MFC after:	2 weeks
2014-12-07 11:21:41 +00:00
jhibbits
a2a568a9e6 Whitespace
X-MFC-with:	r273570
MFC after:	1 week
2014-10-24 03:34:21 +00:00
jhibbits
251119f0e6 Three updates to PowerPC FBT:
* Use a constant to define the number of stack frames in a probe exception.
* Only allow function symbols in powerpc64 ('.' prefixed)
* Set the fbtp_roffset for return probes, so the correct dtrace_probe call is
  made.

MFC after:	1 week
2014-10-24 03:33:01 +00:00
hselasky
49c137f7be Fix multiple incorrect SYSCTL arguments in the kernel:
- Wrong integer type was specified.

- Wrong or missing "access" specifier. The "access" specifier
sometimes included the SYSCTL type, which it should not, except for
procedural SYSCTL nodes.

- Logical OR where binary OR was expected.

- Properly assert the "access" argument passed to all SYSCTL macros,
using the CTASSERT macro. This applies to both static- and dynamically
created SYSCTLs.

- Properly assert the the data type for both static and dynamic
SYSCTLs. In the case of static SYSCTLs we only assert that the data
pointed to by the SYSCTL data pointer has the correct size, hence
there is no easy way to assert types in the C language outside a
C-function.

- Rewrote some code which doesn't pass a constant "access" specifier
when creating dynamic SYSCTL nodes, which is now a requirement.

- Updated "EXAMPLES" section in SYSCTL manual page.

MFC after:	3 days
Sponsored by:	Mellanox Technologies
2014-10-21 07:31:21 +00:00
jhibbits
2ae1525481 Fix the stack tracing for dtrace/powerpc.
Summary:
Fix the stack tracing for dtrace/powerpc by using the trapexit/asttrapexit
return address sentinels instead of checking within the kernel address space.

As part of this, I had to add new inline functions.  FBT traces the kernel, so
we have to have special case handling for this, since a trap will create a full
new trap frame, and there's no way to pass around the 'real' stack.  I handle
this by special-casing 'aframes == 0' with the trap frame.  If aframes counts
out to the trap frame, then assume we're looking for the full kernel trap frame,
so switch to the real stack pointer.

Test Plan: Tested on powerpc64

Reviewers: rpaulo, markj, nwhitehorn

Reviewed By: markj, nwhitehorn

Differential Revision: https://reviews.freebsd.org/D788

MFC after:	3 week
Relnotes:	Yes
2014-09-17 02:43:47 +00:00
markj
46bd89ef4c Restore the correct value when disabling probes. Otherwise the instrumented
tracepoints would continue to generate traps, which would be ignored but
could consume noticeable amounts of CPU if, say, all functions in the kernel
were instrumented.

X-MFC-With:	r270067
2014-08-24 17:10:47 +00:00
markj
ec83007481 Factor out the common code for function boundary tracing instead of
duplicating the entire implementation for both x86 and powerpc. This makes
it easier to add support for other architectures and has no functional
impact.

Phabric:	D613
Reviewed by:	gnn, jhibbits, rpaulo
Tested by:	jhibbits (powerpc)
MFC after:	2 weeks
2014-08-16 21:42:55 +00:00
markj
e18e12eeda Use a C wrapper for trap() instead of checking and calling the DTrace trap
hook in assembly.

Suggested by:	kib
Reviewed by:	kib (original version)
X-MFC-With:	r268600
2014-07-19 02:27:31 +00:00
markj
880dd1a983 Invoke the DTrace trap handler before calling trap() on amd64. This matches
the upstream implementation and helps ensure that a trap induced by tracing
fbt::trap:entry is handled without recursively generating another trap.

This makes it possible to run most (but not all) of the DTrace tests under
common/safety/ without triggering a kernel panic.

Submitted by:	Anton Rang <anton.rang@isilon.com> (original version)
Phabric:	D95
2014-07-14 04:38:17 +00:00
hselasky
35b126e324 Pull in r267961 and r267973 again. Fix for issues reported will follow. 2014-06-28 03:56:17 +00:00
gjb
fc21f40567 Revert r267961, r267973:
These changes prevent sysctl(8) from returning proper output,
such as:

 1) no output from sysctl(8)
 2) erroneously returning ENOMEM with tools like truss(1)
    or uname(1)
 truss: can not get etype: Cannot allocate memory
2014-06-27 22:05:21 +00:00
hselasky
bd1ed65f0f Extend the meaning of the CTLFLAG_TUN flag to automatically check if
there is an environment variable which shall initialize the SYSCTL
during early boot. This works for all SYSCTL types both statically and
dynamically created ones, except for the SYSCTL NODE type and SYSCTLs
which belong to VNETs. A new flag, CTLFLAG_NOFETCH, has been added to
be used in the case a tunable sysctl has a custom initialisation
function allowing the sysctl to still be marked as a tunable. The
kernel SYSCTL API is mostly the same, with a few exceptions for some
special operations like iterating childrens of a static/extern SYSCTL
node. This operation should probably be made into a factored out
common macro, hence some device drivers use this. The reason for
changing the SYSCTL API was the need for a SYSCTL parent OID pointer
and not only the SYSCTL parent OID list pointer in order to quickly
generate the sysctl path. The motivation behind this patch is to avoid
parameter loading cludges inside the OFED driver subsystem. Instead of
adding special code to the OFED driver subsystem to post-load tunables
into dynamically created sysctls, we generalize this in the kernel.

Other changes:
- Corrected a possibly incorrect sysctl name from "hw.cbb.intr_mask"
to "hw.pcic.intr_mask".
- Removed redundant TUNABLE statements throughout the kernel.
- Some minor code rewrites in connection to removing not needed
TUNABLE statements.
- Added a missing SYSCTL_DECL().
- Wrapped two very long lines.
- Avoid malloc()/free() inside sysctl string handling, in case it is
called to initialize a sysctl from a tunable, hence malloc()/free() is
not ready when sysctls from the sysctl dataset are registered.
- Bumped FreeBSD version to indicate SYSCTL API change.

MFC after:	2 weeks
Sponsored by:	Mellanox Technologies
2014-06-27 16:33:43 +00:00
rpaulo
3191dbe25d MFV illumos r266986:
2915 DTrace in a zone should see "cpu", "curpsinfo", et al
2916 DTrace in a zone should be able to access fds[]
2917 DTrace in a zone should have limited provider access

MFC after:	2 weeks
2014-06-26 19:38:16 +00:00
davide
0acfaa5d3d Continue the crusade towards a dev_clone()-free kernel, removing its
usage from dtrace. The dtrace code already uses cdevpriv(9) since FreeBSD
8, so this change should be quite harmless.

Reviewed by:	markj
Approved by:	markj
MFC after:	never
2014-06-25 03:54:02 +00:00
markj
f4fc0f3444 Fix some bugs when fetching probe arguments in i386. Firstly ensure that
the 4 byte-aligned dtrace_invop_callsite can be found and that it
immediately follows the call to dtrace_invop(). Secondly, fix some pointer
arithmetic to account for differences between struct i386_frame and illumos'
struct frame. Finally, ensure that dtrace_getarg() isn't inlined. It works
by following a fixed number of frame pointers to the probe site, so inlining
breaks it.

MFC after:	3 weeks
2014-06-23 02:00:14 +00:00
markj
a10172c6e2 Fix a couple of bugs on amd64 when fetching probe arguments beyond the
first five for probes entered through a UD fault (i.e. FBT probes).

Specifically, handle the fact that dtrace_invop_callsite must be
16 byte-aligned and thus may not immediately follow the call to
dtrace_invop() in dtrace_invop_start(). Also fetch register arguments and
the stack pointer through a struct trapframe instead of a struct reg.

PR:		191260
Submitted by:	luke.tw@gmail.com
MFC after:	3 weeks
2014-06-23 01:10:56 +00:00
markj
8563583ef9 Allow creation of SDT probes from a module in which no providers are
defined. This ensures that the sdt:zfs:: probes appear despite the fact
the sdt provider is defined in the kernel rather than in zfs.ko.

Reported by:	hiren
Tested by:	hiren
MFC after:	2 weeks
2014-06-21 19:29:40 +00:00
grehan
313ef5ff8f Update dis_tables.c to the latest Illumos version.
This includes decodes of recent Intel instructions, in particular
VT-x and related instructions. This allows the FBT provider to
locate the exit points of routines that include these new
instructions.

Illumos issues:
 3414 Need a new word of AT_SUN_HWCAP bits
 3415 Add isainfo support for f16c and rdrand
 3416 Need disassembler support for rdrand and f16c
 3413 isainfo -v overflows 80 columns
 3417 mdb disassembler confuses rdtscp for invlpg
 1518 dis should support AMD SVM/AMD-V/Pacifica instructions
 1096 i386 disassembler should understand complex nops
 1362 add kvmstat for monitoring of KVM statistics
 1363 add vmregs[] variable to DTrace
 1364 need disassembler support for VMX instructions
 1365 mdb needs 16-bit disassembler support

This corresponds to Illumos-gate (github) version
eb23829ff08a873c612ac45d191d559394b4b408

Reviewed by:	markj
MFC after:	1 week
2014-05-15 01:06:27 +00:00