Sets an atomic field on each sampler when it requests a sample, to be
checked when the SIGPROF handler is executed. A counter is not used
since signals may be coalesced.
Prior to this change, all samplers attached to an isolate received
samples when other samplers sent SIGPROF to the VM thread. This change
alters the behaviour of different CpuProfiler instances on the same
isolate to be in line with the Windows / Fuchsia behaviour.
Bug: v8:8835
Change-Id: I0caaa845b596efc9d8b1cd7716c067d9a6359c57
Reviewed-on: https://chromium-review.googlesource.com/c/1468941
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Alexei Filippov <alph@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59545}
Simplify the internal state of Sampler a bit. There are basically two
users of Sampler - the CpuSampler used by the CpuProfiler and the
Ticker used by log.cc. Ticker calls Start/Stop to manage the Sampler
lifetime, but CpuProfiler does not. This leads to much confusion and
overlap of functionality.
Fix that here by removing the distinction between active, registered
and isProfiling states. These are now all the same thing and are
represented by IsActive(). The state is set to active when Start is
called, and set inactive when Stop is called. Both users of Sampler
now call Start and Stop at appropriate times.
The concept of profiling depth was not used - each Sampler would
only ever have a sampling depth of 1. We still need to call
SignalHandler::IncreaseSamplerCount(), so we do that in Start
and the corresponding DecreaseSamplerCount() in Stop.
Change-Id: I16a9435d26169a7dd00b1c7876e66af45f12e4b0
Reviewed-on: https://chromium-review.googlesource.com/c/1424337
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58955}
There's no reason to use our self-baked atomics anymore. Also
- Changes two boolean values to use a boolean instead of an int
- Uses a unique ptr for data_
- Removes has_processing_thread_ which is not used
- Moves most initialization inline into the class
- Removes SetUp/TearDown which weren't needed
Change-Id: I8f50133636961502d56351abd2fb17196603a01a
Reviewed-on: https://chromium-review.googlesource.com/c/1422918
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58950}
Moved class definitions into header
Change-Id: I2d3e5ec6f8f5068284cdbaa6900797950fc7e01a
Reviewed-on: https://chromium-review.googlesource.com/c/1422739
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58946}
Rebuilding (after touching certain files) is crazy slow because
includes are out of control. Many of these files we need to rebuild are
cctests which pull in more includes than they need.
BUG=v8:5294
Review-Url: https://codereview.chromium.org/2304553002
Cr-Commit-Position: refs/heads/master@{#39080}
This patch is based on alph's CL https://codereview.chromium.org/2128613004/.
This patch makes GetStackSample propogate the register state when using
simulator helper, and adds argument to avoid using register state from simulator
when pass the native register state.
BUG=v8:4789
LOG=N
Review-Url: https://codereview.chromium.org/2189513002
Cr-Commit-Position: refs/heads/master@{#38554}
This patch does five things:
1. Extracts sampler as libsampler to provide sampling functionality support.
2. Makes SampleStack virtual so embedders can override the behaviour of sample collecting.
3. Removes sampler.[h|cc].
4. Moves sampling thread into log.cc as workaround to keep the --prof functionality.
5. Creates SamplerManager to manage the relationship between samplers and threads.
The reason we port hashmap.h is that in debug mode, STL containers are using
mutexes from a mutex pool, which may lead to deadlock when using asynchronously
signal handler.
Currently libsampler is used in V8 temporarily.
BUG=v8:4789
LOG=n
Committed: https://crrev.com/06cc9b7c176a6223971deaa9fbcafe1a05058c7b
Cr-Commit-Position: refs/heads/master@{#36527}
Review-Url: https://codereview.chromium.org/1922303002
Cr-Commit-Position: refs/heads/master@{#36532}
Reason for revert:
V8 Linux64 TSAN failure because ThreadSanitizer indicated data race.
Original issue's description:
> Create libsampler as V8 sampler library.
>
> This patch does five things:
>
> 1. Extracts sampler as libsampler to provide sampling functionality support.
> 2. Makes SampleStack virtual so embedders can override the behaviour of sample collecting.
> 3. Removes sampler.[h|cc].
> 4. Moves sampling thread into log.cc as workaround to keep the --prof functionality.
> 5. Creates SamplerManager to manage the relationship between samplers and threads.
>
> The reason we port hashmap.h is that in debug mode, STL containers are using
> mutexes from a mutex pool, which may lead to deadlock when using asynchronously
> signal handler.
>
> Currently libsampler is used in V8 temporarily.
>
> BUG=v8:4789
> LOG=n
>
> Committed: https://crrev.com/06cc9b7c176a6223971deaa9fbcafe1a05058c7b
> Cr-Commit-Position: refs/heads/master@{#36527}
TBR=jochen@chromium.org,alph@chromium.org,fmeawad@chromium.org,yangguo@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4789
Review-Url: https://codereview.chromium.org/2000323007
Cr-Commit-Position: refs/heads/master@{#36529}
This patch does five things:
1. Extracts sampler as libsampler to provide sampling functionality support.
2. Makes SampleStack virtual so embedders can override the behaviour of sample collecting.
3. Removes sampler.[h|cc].
4. Moves sampling thread into log.cc as workaround to keep the --prof functionality.
5. Creates SamplerManager to manage the relationship between samplers and threads.
The reason we port hashmap.h is that in debug mode, STL containers are using
mutexes from a mutex pool, which may lead to deadlock when using asynchronously
signal handler.
Currently libsampler is used in V8 temporarily.
BUG=v8:4789
LOG=n
Review-Url: https://codereview.chromium.org/1922303002
Cr-Commit-Position: refs/heads/master@{#36527}
