During generation code and relocation info are generated simultaneously.
When code generation is done you each code object has associated "relocation info".
Relocation information lets V8 to mark interesting places in the generated code: the pointers that might need to be relocated (after garbage collection),
correspondences between the machine program counter and source locations for stack walking.
This patch:
1. Add more source positions info in reloc info to make it suitable for source level mapping.
The amount of data should not be increased dramatically because (1) V8 already marks interesting places in the generated code and
(2) V8 does not write redundant information (it writes a pair (pc_offset, pos) only if pos is changed and skips other).
I measured it on Octane benchmark - for unoptimized code the number of source positions may achieve 2x ('lin_solve' from NavierStokes benchmark).
2. When a sample happens, CPU profiler finds a code object by pc, then use its reloc info to match the sample to a source line.
If a source line is found that hit counter is increased by one for this line.
3. Add a new public V8 API to get the hit source lines by CDT CPU profiler.
Note that it's expected a minor patch in Blink to pack the source level info in JSON to be shown.
4.Add a test that checks how the samples are distributed through source lines.
It tests two cases: (1) relocation info created during code generation and (2) relocation info associated with precompiled function's version.
Patch from Denis Pravdin <denis.pravdin@intel.com>;
R=svenpanne@chromium.org, yurys@chromium.org
Review URL: https://codereview.chromium.org/682143003
Patch from Weiliang <weiliang.lin@intel.com>.
Cr-Commit-Position: refs/heads/master@{#25182}
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25182 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Reason for revert:
It broke layout test fast/events/window-onerror-02.html, error column reported by window.onerror is now wrong (I believe it is because of the change in full-codegen):
http://build.chromium.org/p/client.v8/builders/V8-Blink%20Linux%2064%20%28dbg%29/builds/652
Original issue's description:
> Extend CPU profiler with mapping ticks to source lines
>
> The idea behind of this solution is to use the existing "relocation info" instead of consumption the CodeLinePosition events emitted by the V8 compilers.
> During generation code and relocation info are generated simultaneously.
> When code generation is done you each code object has associated "relocation info".
> Relocation information lets V8 to mark interesting places in the generated code: the pointers that might need to be relocated (after garbage collection),
> correspondences between the machine program counter and source locations for stack walking.
>
> This patch:
> 1. Add more source positions info in reloc info to make it suitable for source level mapping.
> The amount of data should not be increased dramatically because (1) V8 already marks interesting places in the generated code and
> (2) V8 does not write redundant information (it writes a pair (pc_offset, pos) only if pos is changed and skips other).
> I measured it on Octane benchmark - for unoptimized code the number of source positions may achieve 2x ('lin_solve' from NavierStokes benchmark).
>
> 2. When a sample happens, CPU profiler finds a code object by pc, then use its reloc info to match the sample to a source line.
> If a source line is found that hit counter is increased by one for this line.
>
> 3. Add a new public V8 API to get the hit source lines by CDT CPU profiler.
> Note that it's expected a minor patch in Blink to pack the source level info in JSON to be shown.
>
> 4.Add a test that checks how the samples are distributed through source lines.
> It tests two cases: (1) relocation info created during code generation and (2) relocation info associated with precompiled function's version.
>
> Patch from Denis Pravdin <denis.pravdin@intel.com>
> BUG=None
> LOG=Y
> R=svenpanne@chromium.org
>
> Committed: https://code.google.com/p/v8/source/detail?r=24389TBR=svenpanne@chromium.org,danno@chromium.org,alph@chromium.org,denis.pravdin@intel.com,weiliang.lin@intel.com
BUG=None
LOG=N
Review URL: https://codereview.chromium.org/624443005
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24394 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The idea behind of this solution is to use the existing "relocation info" instead of consumption the CodeLinePosition events emitted by the V8 compilers.
During generation code and relocation info are generated simultaneously.
When code generation is done you each code object has associated "relocation info".
Relocation information lets V8 to mark interesting places in the generated code: the pointers that might need to be relocated (after garbage collection),
correspondences between the machine program counter and source locations for stack walking.
This patch:
1. Add more source positions info in reloc info to make it suitable for source level mapping.
The amount of data should not be increased dramatically because (1) V8 already marks interesting places in the generated code and
(2) V8 does not write redundant information (it writes a pair (pc_offset, pos) only if pos is changed and skips other).
I measured it on Octane benchmark - for unoptimized code the number of source positions may achieve 2x ('lin_solve' from NavierStokes benchmark).
2. When a sample happens, CPU profiler finds a code object by pc, then use its reloc info to match the sample to a source line.
If a source line is found that hit counter is increased by one for this line.
3. Add a new public V8 API to get the hit source lines by CDT CPU profiler.
Note that it's expected a minor patch in Blink to pack the source level info in JSON to be shown.
4.Add a test that checks how the samples are distributed through source lines.
It tests two cases: (1) relocation info created during code generation and (2) relocation info associated with precompiled function's version.
Patch from Denis Pravdin <denis.pravdin@intel.com>
BUG=None
LOG=Y
R=svenpanne@chromium.org
Review URL: https://codereview.chromium.org/616963005
Patch from Denis Pravdin <denis.pravdin@intel.com>.
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24389 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The reuse of CodeCreateEvent for deopt events caused a CodeCreateEvent
fired twice for a code object. When the event was processed for the first
time it seized the no-fp-ranges from code object, so the second event
had no ranges info leaving code entry without them.
As a result when a cpu profile sample falls into the region it missed the
2nd stack frame.
LOG=N
BUG=
R=bmeurer@chromium.org, loislo@chromium.org
Review URL: https://codereview.chromium.org/290093005
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@21418 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- Distinguish between context bound scripts (Script) and context unbound scripts
(UnboundScript).
- Add ScriptCompiler (which will later contain functions for async compilation).
This is a breaking change, in particular, Script::New no longer exists (it is
replaced by ScriptCompiler::CompileUnbound). Script::Compile remains as a
backwards-compatible shorthand for ScriptCompiler::Compile.
Passing CompilerOptions with produce_data_to_cache = true doesn't do anything
yet; the only way to generate the data to cache is the old preparsing API. (To
be fixed in the next version.)
This is a fixed version of https://codereview.chromium.org/186723005/
BUG=
R=dcarney@chromium.org
Review URL: https://codereview.chromium.org/199063003
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19925 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- Distinguish between context bound scripts (Script) and context unbound scripts
(UnboundScript).
- Add ScriptCompiler (which will later contain functions for async compilation).
This is a breaking change, in particular, Script::New no longer exists (it is
replaced by ScriptCompiler::CompileUnbound). Script::Compile remains as a
backwards-compatible shorthand for ScriptCompiler::Compile.
Passing CompilerOptions with produce_data_to_cache = true doesn't do anything
yet; the only way to generate the data to cache is the old preparsing API. (To
be fixed in the next version.)
BUG=
R=dcarney@chromium.org
Review URL: https://codereview.chromium.org/186723005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19881 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
All methods for accessing collected profiles by index are deprecated. The indexed storage may well be implemented by the embedder should he need it. CpuProfiler's responsibility is just to create CpuProfile object that contains all collected data and whose lifetime can be managed by the embedder.
BUG=chromium:327298
LOG=Y
R=svenpanne@chromium.org
Review URL: https://codereview.chromium.org/117353002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@18337 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Made operator* return reference to the raw type, not pointer. New method 'get()' should be used when raw pointer is needed.
Also removed useless inline modifier from the SmaprtPointer methods and added const modifier to the methods that don't change smart pointer.
Made ~SmartPointerBase protected to avoid accidental calls of the non-virtual base class's destructor.
drive-by: fixed use after free in src/factory.cc
BUG=None
LOG=N
R=alph@chromium.org, svenpanne@chromium.org
Review URL: https://codereview.chromium.org/101763003
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@18275 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Profiler is now started from JavaScript. Since we always capture stack trace when starting profiler there should always be at least one expected sample in the profile.
Also changed ProfilerEventsProcessor::AddCurrentStack to make sure it call TickSample::Init to instead of custom initialization code.
BUG=v8:2920
R=jkummerow@chromium.org
Review URL: https://codereview.chromium.org/25686011
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@17140 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
These classes are meant to replace OS::Ticks() and OS::TimeCurrentMillis(),
which are broken in several ways. The ElapsedTimer class implements a
stopwatch using TimeTicks::HighResNow() for high resolution, monotonic
timing.
Also fix the CpuProfile::GetStartTime() and CpuProfile::GetEndTime()
methods to actually return the time relative to the unix epoch as stated
in the documentation (previously that was relative to some arbitrary
point in time, i.e. boot time).
The previous Windows issues have been resolved, and we now use GetTickCount64()
on Windows Vista and later, falling back to timeGetTime() with rollover
protection for earlier Windows versions.
BUG=v8:2853
R=machenbach@chromium.org, yurys@chromium.org
Review URL: https://codereview.chromium.org/23490015
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16413 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
These classes are meant to replace OS::Ticks() and OS::TimeCurrentMillis(),
which are broken in several ways. The ElapsedTimer class implements a
stopwatch using TimeTicks::HighResNow() for high resolution, monotonic
timing.
Also fix the CpuProfile::GetStartTime() and CpuProfile::GetEndTime()
methods to actually return the time relative to the unix epoch as stated
in the documentation (previously that was relative to some arbitrary
point in time, i.e. boot time).
BUG=v8:2853
R=machenbach@chromium.org
Review URL: https://codereview.chromium.org/23469013
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16398 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
These classes are meant to replace OS::Ticks() and OS::TimeCurrentMillis(),
which are broken in several ways. The ElapsedTimer class implements a
stopwatch using TimeTicks::HighResNow() for high resolution, monotonic
timing.
Also fix the CpuProfile::GetStartTime() and CpuProfile::GetEndTime()
methods to actually return the time relative to the unix epoch as stated
in the documentation (previously that was relative to some arbitrary
point in time, i.e. boot time).
BUG=v8:2853
R=machenbach@chromium.org, yurys@chromium.org
Review URL: https://codereview.chromium.org/23295034
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16388 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
New flag is added that allows to specify CPU profiler sampling rate in microseconds as command line argument. It was tested to work fine with 100us interval(currently it is 1ms). Default values are kept the same as in the current implementation. The new implementation is enabled only on POSIX platforms which use signals to collect samples. Other platforms that pause thread being sampled are to follow.
SIGPROF signals are now sent on the profiler event processor thread to make sure that the processing thread does fall far behind the sampling.
The patch is based on the previous one that was rolled out in r13851. The main difference is that the circular queue is not modified for now.
On Linux sampling for CPU profiler is initiated on the profiler event processor thread, other platforms to follow.
CPU profiler continues to use SamplingCircularQueue, we will probably replace it with a single sample buffer when Mac and Win ports support profiling on the event processing thread.
When --prof option is specified profiling is initiated either on the profiler event processor thread if CPU profiler is on or on the SignalSender thread as it used to be if no CPU profiles are being collected.
ProfilerEventsProcessor::ProcessEventsAndDoSample now waits in a tight loop, processing collected samples until sampling interval expires. To save CPU resources I'm planning to change that to use nanosleep as only one sample is expected in the queue at any point.
BUG=v8:2814
R=bmeurer@chromium.org
Review URL: https://codereview.chromium.org/21101002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16310 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
