Depends on D89283.
The goal of this packet (jTraceGetSupportedType) is to be able to query the gdb-server for the tracing technology that can work for the current debuggeer, which can make the user experience simpler but allowing the user to simply type
thread trace start
to start tracing the current thread without even telling the debugger to use "intel-pt", for example. Similarly, `thread trace start [args...]` would accept args beloging to the working trace type.
Also, if the user typed
help thread trace start
We could directly show the help information of the trace type that is supported for the target, or mention instead that no tracing is supported, if that's the case.
I added some simple tests, besides, when I ran this on my machine with intel-pt support, I got
$ process plugin packet send "jTraceSupportedType"
packet: jTraceSupportedType
response: {"description":"Intel Processor Trace","pluginName":"intel-pt"}
On a machine without intel-pt support, I got
$ process plugin packet send "jTraceSupportedType"
packet: jTraceSupportedType
response: E00;
Reviewed By: clayborg, labath
Differential Revision: https://reviews.llvm.org/D90490
As mentioned in the comment inside the code, the Intel documentation
states that the internal CPU buffer is flushed out to RAM only when tracing is
disabled. Otherwise, the buffer on RAM might be stale.
This diff disables tracing when the trace buffer is going to be read. This is a
quite safe operation, as the reading is done when the inferior is paused at a
breakpoint, so we are not losing any packets because there's no code being
executed.
After the reading is finished, tracing is enabled back.
It's a bit hard to write a test for this now, but Greg Clayton and I will
refactor the PT support and writing tests for it will be easier. However
I tested it manually by doing a script that automates
the following flow
```
(lldb) b main
Breakpoint 1: where = a.out`main + 15 at main.cpp:4:7, address = 0x000000000040050f
(lldb) r
Process 3078226 stopped
* thread #1, name = 'a.out', stop reason = breakpoint 1.1
frame #0: 0x000000000040050f a.out`main at main.cpp:4:7
(lldb) processor-trace start
(lldb) b 5
Breakpoint 2: where = a.out`main + 22 at main.cpp:5:12, address = 0x0000000000400516
(lldb) c
Process 3078226 resuming
Process 3078226 stopped
* thread #1, name = 'a.out', stop reason = breakpoint 2.1
frame #0: 0x0000000000400516 a.out`main at main.cpp:5:12
(lldb) processor-trace show-instr-log
thread #1: tid=3078226
0x40050f <+15>: movl $0x0, -0x8(%rbp)
>>> Before, some runs of the script up to this point lead to empty traces
(lldb) b 6
Breakpoint 3: where = a.out`main + 42 at main.cpp:6:14, address = 0x000000000040052a
(lldb) c
Process 3092991 resuming
Process 3092991 stopped
* thread #1, name = 'a.out', stop reason = breakpoint 3.1
frame #0: 0x000000000040052a a.out`main at main.cpp:6:14
(lldb) processor-trace show-instr-log thread #1: tid=3092991
0x40050f <+15>: movl $0x0, -0x8(%rbp)
0x400516 <+22>: movl $0x0, -0xc(%rbp)
0x40051d <+29>: cmpl $0x2710, -0xc(%rbp) ; imm = 0x2710
0x400524 <+36>: jge 0x400546 ; <+70> at main.cpp
0x400524 <+36>: jge 0x400546 ; <+70> at main.cpp
>>> The trace was re-enabled correctly and includes the instruction of the
first reading.
```
Those instructions correspond to these lines
```
3 int main() {
4 int z = 0;
5 for (int i = 0; i < 10000; i++) {
6 z += fun(z)
...
```
Differential Revision: https://reviews.llvm.org/D85241
Summary:
A *.cpp file header in LLDB (and in LLDB) should like this:
```
//===-- TestUtilities.cpp -------------------------------------------------===//
```
However in LLDB most of our source files have arbitrary changes to this format and
these changes are spreading through LLDB as folks usually just use the existing
source files as templates for their new files (most notably the unnecessary
editor language indicator `-*- C++ -*-` is spreading and in every review
someone is pointing out that this is wrong, resulting in people pointing out that this
is done in the same way in other files).
This patch removes most of these inconsistencies including the editor language indicators,
all the different missing/additional '-' characters, files that center the file name, missing
trailing `===//` (mostly caused by clang-format breaking the line).
Reviewers: aprantl, espindola, jfb, shafik, JDevlieghere
Reviewed By: JDevlieghere
Subscribers: dexonsmith, wuzish, emaste, sdardis, nemanjai, kbarton, MaskRay, atanasyan, arphaman, jfb, abidh, jsji, JDevlieghere, usaxena95, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D73258
Summary:
NFC = [[ https://llvm.org/docs/Lexicon.html#nfc | Non functional change ]]
This commit is the result of modernizing the LLDB codebase by using
`nullptr` instread of `0` or `NULL`. See
https://clang.llvm.org/extra/clang-tidy/checks/modernize-use-nullptr.html
for more information.
This is the command I ran and I to fix and format the code base:
```
run-clang-tidy.py \
-header-filter='.*' \
-checks='-*,modernize-use-nullptr' \
-fix ~/dev/llvm-project/lldb/.* \
-format \
-style LLVM \
-p ~/llvm-builds/debug-ninja-gcc
```
NOTE: There were also changes to `llvm/utils/unittest` but I did not
include them because I felt that maybe this library shall be updated in
isolation somehow.
NOTE: I know this is a rather large commit but it is a nobrainer in most
parts.
Reviewers: martong, espindola, shafik, #lldb, JDevlieghere
Reviewed By: JDevlieghere
Subscribers: arsenm, jvesely, nhaehnle, hiraditya, JDevlieghere, teemperor, rnkovacs, emaste, kubamracek, nemanjai, ki.stfu, javed.absar, arichardson, kbarton, jrtc27, MaskRay, atanasyan, dexonsmith, arphaman, jfb, jsji, jdoerfert, lldb-commits, llvm-commits
Tags: #lldb, #llvm
Differential Revision: https://reviews.llvm.org/D61847
llvm-svn: 361484
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
Summary:
The std::move was preventing copy ellision when compiled with
clang, the patch fixes the warning along with rearranging code
to remove unused variables warnings on Linux machines with
older perf_event interface.
Reviewers: labath, ted
Reviewed By: labath
Differential Revision: https://reviews.llvm.org/D34946
llvm-svn: 307030
Summary:
This patch implements support for Intel(R) Processor Trace
in lldb server. The changes have support for
starting/stopping and reading the trace data. The code
is only available on Linux versions where the perf
attributes for aux buffers are available.
The patch also consists of Unit tests for testing the
core buffer reading function.
Reviewers: lldb-commits, labath, clayborg, zturner, tberghammer
Reviewed By: labath, clayborg
Subscribers: mgorny
Differential Revision: https://reviews.llvm.org/D33674
llvm-svn: 306516
Walter Erquinigo