It is not needed after commit 7e80fd5ef397. No functional change
intended.
Reviewed by: avg
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D46675
FBT refuses to create probes in modules which depend on dtrace(all), but
dtrace_test is a convenient place to add functions specifically for
testing dtrace.
The dependency on dtraceall is not needed, so just remove it. In fact,
it can be useful to test SDT probe creation by loading dtrace_test with
and without dtraceall loaded.
Reviewed by: avg
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D46673
dtrace_getarg() previously walked the call stack looking for a frame
matching the dtrace_invop_callsite symbol, in order to look for a
trapframe corresponding to an invop (i.e., FBT or kinst) probe. Commit
3ba8e9dc4a broke this in some cases by breaking the expected alignment
of the dtrace_invop_callsite symbol.
Rather than groveling around the stack to find invop probe arguments,
simply use the trapframe reference saved by dtrace_invop(). This is
simpler and less fragile.
Reported by: avg
Reviewed by: avg
MFC after: 2 weeks
Fixes: 3ba8e9dc4a ("dtrace/amd64: Implement emulation of call instructions")
Differential Revision: https://reviews.freebsd.org/D46672
This was done in the original DTrace import, presumably because that
made it a bit easier to handle includes. However, this can cause
dtrace_getpcstack() to be inlined into dtrace_probe(), resulting in a
missing frame in stack traces since dtrace_getpcstack() takes care to
bump "aframes" to account for its own stack frame.
To avoid this, compile dtrace_isa.c separately on all platforms. Add
requisite includes.
MFC after: 2 weeks
Sponsored by: Innovate UK
For invop providers (i.e., fbt and kinst) we can simply reach into the
invop trapframe to fetch argument registers for arguments 0-7; for
argument 8 and beyond we have to read the value off of the stack.
Reviewed by: Domagoj Stolfa, avg
MFC after: 2 weeks
Sponsored by: Innovate UK
Differential Revision: https://reviews.freebsd.org/D45649
SDT calls dtrace_probe() directly, and this can be used to pass up to
five probe arguments directly. To pass the sixth argument (SDT
currently doesn't support more than this), we use a hack: just add
additional parameters to the call and cast dtrace_probe accordingly.
This happens to work on amd64, but doesn't work in general.
Modify SDT to call dtrace_probe() after storing arguments beyond the
first five in thread-local storage. Implement sdt_getargval() to fetch
extra argument values this way. An alternative would be to use invop
handlers instead and make sdt_probe_func point to a breakpoint
instruction, so that one can extract arguments using the breakpoint
exception trapframe, but this makes the providers more expensive when
enabled and doesn't seem justified. This approach works well unless we
want to add more than one or two more parameters to SDT probes, which
seems unlikely at present.
In particular, this fixes fetching the last argument of most ip and tcp
probes on arm64.
Reported by: rwatson
Reviewed by: Domagoj Stolfa
MFC after: 1 month
Sponsored by: Innovate UK
Differential Revision: https://reviews.freebsd.org/D45648
The idea here is to avoid a memory access and conditional branch per
probe site. Instead, the probe is represented by an "unreachable"
unconditional function call. asm goto is used to store the address of
the probe site (represented by a no-op sled) and the address of the
function call into a tracepoint record. Each SDT probe carries a list
of tracepoints.
When the probe is enabled, the no-op sled corresponding to each
tracepoint is overwritten with a jmp to the corresponding label. The
implementation uses smp_rendezvous() to park all other CPUs while the
instruction is being overwritten, as this can't be done atomically in
general. The compiler moves argument marshalling code and the
sdt_probe() function call out-of-line, i.e., to the end of the function.
Per gallatin@ in D43504, this approach has less overhead when probes are
disabled. To make the implementation a bit simpler, I removed support
for probes with 7 arguments; nothing makes use of this except a
regression test case. It could be re-added later if need be.
The approach taken in this patch enables some more improvements:
1. We can now automatically fill out the "function" field of SDT probe
names. The SDT macros let the programmer specify the function and
module names, but this is really a bug and shouldn't have been
allowed. The intent was to be able to have the same probe in
multiple functions and to let the user restrict which probes actually
get enabled by specifying a function name or glob.
2. We can avoid branching on SDT_PROBES_ENABLED() by adding the ability
to include blocks of code in the out-of-line path. For example:
if (SDT_PROBES_ENABLED()) {
int reason = CLD_EXITED;
if (WCOREDUMP(signo))
reason = CLD_DUMPED;
else if (WIFSIGNALED(signo))
reason = CLD_KILLED;
SDT_PROBE1(proc, , , exit, reason);
}
could be written
SDT_PROBE1_EXT(proc, , , exit, reason,
int reason;
reason = CLD_EXITED;
if (WCOREDUMP(signo))
reason = CLD_DUMPED;
else if (WIFSIGNALED(signo))
reason = CLD_KILLED;
);
In the future I would like to use this mechanism more generally, e.g.,
to remove branches and marshalling code used by hwpmc, and generally to
make it easier to add new tracepoint consumers without having to add
more conditional branches to hot code paths.
Reviewed by: Domagoj Stolfa, avg
MFC after: 2 months
Differential Revision: https://reviews.freebsd.org/D44483
LLD has the -zbti-report=error argument to check if the BTI note is
present when linking. To allow for this to be used when linking the
kernel and modules:
- Add the BTI note to the remaining assembly files
- Mark ptrauth.c as protected by BTI
- Disable -zbti-report for vmm hypervisor switching code as it's not
used there.
The linux64 module doesn't build with the flag as it includes vdso code
that doesn't include the note.
Reviewed by: imp, kib, emaste
Sponsored by: Arm Ltd
Differential Revision: https://reviews.freebsd.org/D45466
Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.
Remove /^#if.*\n#endif.*\n#include\s+<sys/cdefs.h>.*\n/
Remove /\n+#include\s+<sys/cdefs.h>.*\n+#if.*\n#endif.*\n+/
Remove /\n+#if.*\n#endif.*\n+/
Remove /^#if.*\n#endif.*\n/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/types.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/param.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/capsicum.h>/
Sponsored by: Netflix
Remove ancient SCCS tags from the tree, automated scripting, with two
minor fixup to keep things compiling. All the common forms in the tree
were removed with a perl script.
Sponsored by: Netflix
This reverts commit 22508c8b6c.
The t_kinst_curprobe field is no longer needed by kinst.
Reviewed by: markj
Approved by: markj (mentor)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D41031
Needed by the forthcoming RISC-V and ARM64 ports.
Reviewed by: markj
Approved by: markj (mentor)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40872
Use unprivileged loads to access user memory. Without this, the
accesses trap and various dtrace actions such as ustack() fail.
Reviewed by: andrew
MFC after: 1 week
Sponsored by: Innovate UK
Differential Revision: https://reviews.freebsd.org/D40540
It was used in one place and was added specifically to support dtrace
stack unwinding code. Write an equivalent expression using struct
unwind_state instead. No functional change intended.
Reviewed by: andrew
MFC after: 1 week
Sponsored by: Innovate UK
Differential Revision: https://reviews.freebsd.org/D40538
The forthcoming RISC-V and ARM64 ports of kinst introduce a new field
named "t_kinst_curprobe", so "t_kinst" (which points to a trampoline)
becomes a misleading name.
No functional change intended.
Reviewed by: markj
Approved by: markj (mentor)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40507
match_opcode() is defined in FBT, kinst, and dtrace_subr.c. The function
prologue-checking functions are defined in FBT and kinst.
Reviewed by: markj
Approved by: markj (mentor)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40335
kinst uses this function as well, but because it is not exported, it
implements its own copy of it. The patch also exposes the function to
userland, so programs that need to use dtrace_disx86() can use this
function instead of rolling their own copies.
Reviewed by: markj
Approved by: markj (mentor)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D39871
This brings in the following commits:
commit 584b574a3b16c6772c8204ec1d1c957c56f22a87
12174 i86pc: variable may be used uninitialized
Author: Toomas Soome <tsoome@me.com>
Reviewed by: John Levon <john.levon@joyent.com>
Reviewed by: Andrew Stormont <astormont@racktopsystems.com>
Approved by: Dan McDonald <danmcd@joyent.com>
commit a25e615d76804404e5fc63897a9196d4f92c3f5e
12371 dis x86 EVEX prefix mishandled
12372 dis EVEX encoding SIB mishandled
12373 dis support for EVEX vaes instructions
12374 dis support for EVEX vpclmulqdq instructions
12375 dis support for gfni instructions
Author: Robert Mustacchi <rm@fingolfin.org>
Reviewed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Approved by: Joshua M. Clulow <josh@sysmgr.org>
commit c1e9bf00765d7ac9cf1986575e4489dd8710d9b1
12369 dis WBNOINVD support
Author: Robert Mustacchi <rm@joyent.com>
Reviewed by: Hans Rosenfeld <hans.rosenfeld@joyent.com>
Reviewed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Reviewed by: Andy Fiddaman <andy@omniosce.org>
Reviewed by: Toomas Soome <tsoome@me.com>
Approved by: Dan McDonald <danmcd@joyent.com>
commit e4f6ce7088a7dd335b9edf4774325f888692e5fb
10893 Need support for new Cascade Lake Instructions
Author: Robert Mustacchi <rm@joyent.com>
Reviewed by: Hans Rosenfeld <hans.rosenfeld@joyent.com>
Reviewed by: Dan McDonald <danmcd@joyent.com>
Reviewed by: Richard Lowe <richlowe@richlowe.net>
Approved by: Gordon Ross <gwr@nexenta.com>
commit cff040f3ef42d16ae655969398f5a5e6e700b85e
10226 Need support for new EPYC ISA extensions
Author: Robert Mustacchi <rm@joyent.com>
Reviewed by: Hans Rosenfeld <hans.rosenfeld@joyent.com>
Reviewed by: Jason King <jason.king@joyent.com>
Reviewed by: Richard Lowe <richlowe@richlowe.net>
Approved by: Dan McDonald <danmcd@joyent.com>
commit d242cdf5288b86d9070d88791c8ee696612becdc
8492 AVX512 dis - legacy logical instructions
Author: Jerry Jelinek <jerry.jelinek@joyent.com>
Reviewed by: Robert Mustacchi <rm@joyent.com>
Reviewed by: Gordon Ross <gordon.w.ross@gmail.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
commit 81b505b772ab015c588c56bb116239ee549b6eee
8384 AVX512 dis - EVEX prefix support
8385 32-bit avx dis test mishandles EVEX prefix
8386 32-bit bound dis is incorrect
Author: Jerry Jelinek <jerry.jelinek@joyent.com>
Reviewed by: Robert Mustacchi <rm@joyent.com>
Reviewed by: Gordon Ross <gordon.w.ross@gmail.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
commit 92381362ae635a3bea638d87b7119f1623b6212e
8319 dis support for new xsave instructions
Author: Jerry Jelinek <jerry.jelinek@joyent.com>
Reviewed by: Robert Mustacchi <rm@joyent.com>
Reviewed by: Gordon Ross <gordon.w.ross@gmail.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
commit a4e73d5d60e566669c550027fae2b1d87b4be2b4
8240 AVX512 dis - opmask instruction support
Author: Jerry Jelinek <jerry.jelinek@joyent.com>
Reviewed by: Robert Mustacchi <rm@joyent.com>
Reviewed by: Toomas Soome <tsoome@me.com>
Approved by: Gordon Ross <gordon.w.ross@gmail.com>
959b2dfd39979fe8a9a315a52741d009eb168822
7825 want avx dis tests
7826 PCLMULQDQ psuedo-ops aren't properly described in dis
7827 dis tests for f16c, movbe, cpuid, msr, tsc, fence instrs
7828 sysenter and sysexit dis should be allowed in 64-bit x86
Author: Robert Mustacchi <rm@joyent.com>
Reviewed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
MFC after: 2 weeks
dtrace_instr_size() is needed by the forthcoming RISC-V port of kinst,
as well as by libdtrace in D38825 for both amd64 and RISC-V.
Reviewed by: markj, mhorne
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D39489
Callers are specifying uint8_t anyway and this slightly reduces
dependencies on compatibility typedefs. No functional change intended.
Reviewed by: markj, mhorne
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D39490
This will be used by a forthcoming port of the kinst provider.
Reviewed by: markj
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D39481
In function boundary tracing the link register is not yet saved to the
save stack location, so the save point contains whatever the previous
'lr' save was, or even garbage, at the time the trap is taken. Address
this by explicitly loading the link register from the trap frame instead
of the stack, and propagate that out.
Pretty trivial following other implementations. The existing
dtrace_getustack_common() does most of the work.
Reviewed by: markj
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D38303
The unwind logic was copied from AArch64 which follows the peculiar
AACPS (where, unlike typical RISC architectures, its frame pointer
follows an x86/stack machine-like convention where the frame pointer
points at the bottom of the frame record, not the top). Delete the
pointless riscv_frame struct and fix this.
Reviewed by: mhorne
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D28054
We must detect the correct amount to increment sepc, as it may have been
a compressed instruction that triggered the fault.
Reviewed by: markj
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D38299
In order to read or write userspace memory without generating an access
fault, we must first enable the SUM bit in the sstatus CSR.
Reviewed by: markj
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D38298
Backtraces for fbt probes are missing the caller's frame. Despite what
the inherited comment claims, we do need to insert this manually on
riscv. In fbt_invop(), set cpu_dtrace_caller to be the return address,
not addr.
We should not increment aframes within this function, since we begin the
main loop by unwinding past the current frame.
Plus some very small comment/style tweaks.
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D37661
These are fixed, so having upstream's version is not especially useful,
and the duplicated definitions make for confusing reading. No
functional change intended.
MFC after: 1 week
This is a new DTrace provider which allows arbitrary kernel instructions
to be traced. Currently it is implemented only for amd64.
kinst probes are created on demand by libdtrace, and there is a probe
for each kernel instruction. Probes are named
kinst:<module>:<function>:<offset>, where "offset" is the offset of the
target instruction relative to the beginning of the function. Omitting
"offset" causes all instructions in the function to be traced.
kinst works similarly to FBT in that it places a breakpoint on the
target instruction and hooks into the kernel breakpoint handler.
Because kinst has to be able to trace arbitrary instructions, it does
not emulate most of them in software but rather causes the traced thread
to execute a copy of the instruction before returning to the original
code.
The provider is quite low-level and as-is will be useful mostly only to
kernel developers. However, it provides a great deal of visibility into
kernel code execution and could be used as a building block for
higher-level tooling which can in some sense translate between C sources
and generated machine code. In particular, the "regs" variable recently
added to D allows the CPU's register file to be accessed from kinst
probes.
kinst is experimental and should not be used on production systems for
now.
In collaboration with: markj
Sponsored by: Google, Inc. (GSoC 2022)
MFC after: 3 months
Differential Revision: https://reviews.freebsd.org/D36851
This allows invop-based providers (i.e., fbt and kinst) to expose the
register file of the CPU at the point where the probe fired. It does
not work for SDT providers because their probes are implemented as plain
function calls and so don't save registers. It's not clear what
semantics "regs" should have for them anyway.
This is akin to "uregs", which nominally provides access to the
userspace registers. In fact, DIF already had a DIF_VAR_REGS variable
defined, it was simply unimplemented.
Usage example: print the contents of %rdi upon each call to
amd64_syscall():
fbt::amd64_syscall:entry {printf("%x", regs[R_RDI]);}
Note that the R_* constants are defined in /usr/lib/dtrace/regs_x86.d.
Currently there are no similar definitions for non-x86 platforms.
Reviewed by: christos
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D36799
With clang 15, the following -Werror warning is produced:
sys/cddl/dev/dtrace/riscv/dtrace_subr.c:165:17: error: a function declaration without a prototype is deprecated in all versions of C [-Werror,-Wstrict-prototypes]
dtrace_gethrtime()
^
void
This is because dtrace_gethrtime() is declared with a (void) argument
list, but defined with an empty argument list. Make the definition match
the declaration.
MFC after: 3 days
With clang 15, the following -Werror warning is produced:
sys/cddl/dev/dtrace/powerpc/dtrace_subr.c:237:17: error: a function declaration without a prototype is deprecated in all versions of C [-Werror,-Wstrict-prototypes]
dtrace_gethrtime()
^
void
This is because dtrace_gethrtime() is declared with a (void) argument
list, but defined with an empty argument list. Make the definition match
the declaration.
MFC after: 3 days
With clang 15, the following -Werror warning is produced:
sys/cddl/dev/dtrace/arm/dtrace_subr.c:174:17: error: a function declaration without a prototype is deprecated in all versions of C [-Werror,-Wstrict-prototypes]
dtrace_gethrtime()
^
void
This is because dtrace_gethrtime() is declared with a (void) argument
list, but defined with an empty argument list. Make the definition match
the declaration.
MFC after: 3 days
Here, the provider is responsible for updating the trapframe to redirect
control flow and for computing the return address. Once software-saved
registers are restored, the emulation shifts the remaining context down
on the stack to make space for the return address, then copies the
address provided by the invop handler. dtrace_invop() is modified to
allocate temporary storage space on the stack for use by the provider to
return the return address.
This is to support a new provider for amd64 which can instrument
arbitrary instructions, not just function entry and exit instructions as
FBT does.
In collaboration with: christos
Sponsored by: Google, Inc. (GSoC 2022)
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
With clang 15, the following -Werror warnings is produced:
In file included from sys/cddl/contrib/opensolaris/uts/common/dtrace/dtrace.c:18440:
sys/cddl/dev/dtrace/dtrace_unload.c:26:14: error: a function declaration without a prototype is deprecated in all versions of C [-Werror,-Wstrict-prototypes]
dtrace_unload()
^
void
This is because dtrace_unload() is declared with a (void) argument list,
but defined with an empty argument list. Make the definition match the
declaration.
MFC after: 3 days
We had a hardcoded limit of 1/128-th of physical memory that was further
subdivided between all CPUs as principal buffers are allocated on the
per-CPU basis. Actually, the buffers could use up 1/64-th of the
memmory because with the default switch policy there are two buffers per
CPU.
This commit allows to change that limit.
Note that the discussed limit is per dtrace command invocation.
The idea is to limit the size of a single malloc(9) call, not the total
memory size used by DTrace buffers.
Reviewed by: markj
MFC after: 3 weeks
Differential Revision: https://reviews.freebsd.org/D33648
