go/src/runtime/cpuprof.go

const maxCPUProfStack …

const profBufWordCount …

const profBufTagCount …

type cpuProfile …

var cpuprof …

// SetCPUProfileRate sets the CPU profiling rate to hz samples per second.
// If hz <= 0, SetCPUProfileRate turns off profiling.
// If the profiler is on, the rate cannot be changed without first turning it off.
//
// Most clients should use the [runtime/pprof] package or
// the [testing] package's -test.cpuprofile flag instead of calling
// SetCPUProfileRate directly.
func SetCPUProfileRate(hz int) { … }

// add adds the stack trace to the profile.
// It is called from signal handlers and other limited environments
// and cannot allocate memory or acquire locks that might be
// held at the time of the signal, nor can it use substantial amounts
// of stack.
//
//go:nowritebarrierrec
func (p *cpuProfile) add(tagPtr *unsafe.Pointer, stk []uintptr) { … }

// addNonGo adds the non-Go stack trace to the profile.
// It is called from a non-Go thread, so we cannot use much stack at all,
// nor do anything that needs a g or an m.
// In particular, we can't call cpuprof.log.write.
// Instead, we copy the stack into cpuprof.extra,
// which will be drained the next time a Go thread
// gets the signal handling event.
//
//go:nosplit
//go:nowritebarrierrec
func (p *cpuProfile) addNonGo(stk []uintptr) { … }

// addExtra adds the "extra" profiling events,
// queued by addNonGo, to the profile log.
// addExtra is called either from a signal handler on a Go thread
// or from an ordinary goroutine; either way it can use stack
// and has a g. The world may be stopped, though.
func (p *cpuProfile) addExtra() { … }

// CPUProfile panics.
// It formerly provided raw access to chunks of
// a pprof-format profile generated by the runtime.
// The details of generating that format have changed,
// so this functionality has been removed.
//
// Deprecated: Use the [runtime/pprof] package,
// or the handlers in the [net/http/pprof] package,
// or the [testing] package's -test.cpuprofile flag instead.
func CPUProfile() []byte { … }

// runtime/pprof.runtime_cyclesPerSecond should be an internal detail,
// but widely used packages access it using linkname.
// Notable members of the hall of shame include:
//   - github.com/grafana/pyroscope-go/godeltaprof
//   - github.com/pyroscope-io/godeltaprof
//
// Do not remove or change the type signature.
// See go.dev/issue/67401.
//
//go:linkname pprof_cyclesPerSecond runtime/pprof.runtime_cyclesPerSecond
func pprof_cyclesPerSecond() int64 { … }

// readProfile, provided to runtime/pprof, returns the next chunk of
// binary CPU profiling stack trace data, blocking until data is available.
// If profiling is turned off and all the profile data accumulated while it was
// on has been returned, readProfile returns eof=true.
// The caller must save the returned data and tags before calling readProfile again.
// The returned data contains a whole number of records, and tags contains
// exactly one entry per record.
//
// runtime_pprof_readProfile should be an internal detail,
// but widely used packages access it using linkname.
// Notable members of the hall of shame include:
//   - github.com/pyroscope-io/pyroscope
//
// Do not remove or change the type signature.
// See go.dev/issue/67401.
//
//go:linkname runtime_pprof_readProfile runtime/pprof.readProfile
func runtime_pprof_readProfile() ([]uint64, []unsafe.Pointer, bool) { … }