class ThreadSamplerDispatcher
Defined at line 55 of file ../../zircon/kernel/lib/thread_sampler/include/lib/thread_sampler/thread_sampler.h
A ThreadSampler is really just an IOBuffer with some added control methods on top to start and
stop sampling.
Public Methods
void ~ThreadSamplerDispatcher ()Defined at line 57 of file ../../zircon/kernel/lib/thread_sampler/include/lib/thread_sampler/thread_sampler.h
SamplingState State ()Defined at line 75 of file ../../zircon/kernel/lib/thread_sampler/include/lib/thread_sampler/thread_sampler.h
void SetCurrCpuTimer ()Set a timer based on the configured duration. When the timer expires, the currently running
thread will be marked to take a sample.
Defined at line 368 of file ../../zircon/kernel/lib/thread_sampler/thread_sampler.cc
void OnPeerZeroHandlesLocked ()When the user drops their end of the buffer/sampler, we need to stop sampling and clean up the
state.
Defined at line 339 of file ../../zircon/kernel/lib/thread_sampler/thread_sampler.cc
zx::result<KernelHandle<ThreadSamplerDispatcher>> Create (const zx_sampler_config_t & config)Defined at line 372 of file ../../zircon/kernel/lib/thread_sampler/thread_sampler.cc
zx::result<> Start (const fbl::RefPtr<IoBufferDispatcher> & disp)Defined at line 415 of file ../../zircon/kernel/lib/thread_sampler/thread_sampler.cc
zx::result<> Stop (const fbl::RefPtr<IoBufferDispatcher> & disp)Defined at line 404 of file ../../zircon/kernel/lib/thread_sampler/thread_sampler.cc
zx::result<> AddThread (const fbl::RefPtr<IoBufferDispatcher> & disp, const fbl::RefPtr<ThreadDispatcher> & thread)zx::result<> SampleThread (zx_koid_t pid, zx_koid_t tid, GeneralRegsSource source, void * gregs)Given a thread's registers, pid, and tid, walk the thread's user stack and write each
pointer to the sampling buffers if sampling is enabled.
WARNING: SampleThread both
a) does a large number of user copies, and
b) allocates a large amount of stack space
It should only be called from Thread::Current::ProcessPendingSignals where we can be user that
the user copies are safe to do and where the current stack size should be relatively shallow.
Defined at line 426 of file ../../zircon/kernel/lib/thread_sampler/thread_sampler.cc
ktl::pair<zx_status_t, size_t> ReadUser (const fbl::RefPtr<IoBufferDispatcher> & disp, user_out_ptr<void> ptr, size_t len)Read out the data contained in the sampler buffers into `ptr` return the number of bytes
written. The Sampling state must be Stopped before calling this function.
`len` _must_ be at least equal to the total size of the sampler buffers, which can be queried
by passing a nullptr `ptr`. In this case, no data will be written and the return value will be
the required minimum size of the buffer to write to.
Defined at line 451 of file ../../zircon/kernel/lib/thread_sampler/thread_sampler.cc
Protected Methods
internal::PerCpuState & GetPerCpuState (size_t i)Defined at line 109 of file ../../zircon/kernel/lib/thread_sampler/include/lib/thread_sampler/thread_sampler.h
void ThreadSamplerDispatcher (fbl::RefPtr<PeerHolder<IoBufferDispatcher>> holder, IobEndpointId endpoint_id, fbl::RefPtr<SharedIobState> shared_state)Defined at line 111 of file ../../zircon/kernel/lib/thread_sampler/include/lib/thread_sampler/thread_sampler.h
zx::result<> CreateImpl (const zx_sampler_config_t & config, KernelHandle<ThreadSamplerDispatcher> & read_handle_out, KernelHandle<ThreadSamplerDispatcher> & write_handle_out)Create a ThreadSamplerDispatcher. The ThreadSamplerDispatcher is a peered object with one end
readable and one end writable. The write end is retained by the kernel to write samples to. The
user receives the read end of the buffer so that they may read the samples written.
Defined at line 25 of file ../../zircon/kernel/lib/thread_sampler/thread_sampler.cc
zx::result<> SampleThreadImpl (zx_koid_t pid, zx_koid_t tid, GeneralRegsSource source, void * gregs)Given information about a thread and its registers, walk its userstack and write out a sample
if sampling is enabled.
Defined at line 201 of file ../../zircon/kernel/lib/thread_sampler/thread_sampler.cc
zx::result<> StartImpl ()Defined at line 130 of file ../../zircon/kernel/lib/thread_sampler/thread_sampler.cc
zx::result<> StopImpl ()Defined at line 150 of file ../../zircon/kernel/lib/thread_sampler/thread_sampler.cc
Enumerations
enum SamplingState| Name | Value |
|---|---|
| Configured | 0 |
| Running | 1 |
| Reading | 2 |
| Destroying | 3 |
| Destroyed | 4 |
Defined at line 67 of file ../../zircon/kernel/lib/thread_sampler/include/lib/thread_sampler/thread_sampler.h