go/src/runtime/debug.go

// GOMAXPROCS sets the maximum number of CPUs that can be executing
// simultaneously and returns the previous setting. It defaults to
// the value of [runtime.NumCPU]. If n < 1, it does not change the current setting.
// This call will go away when the scheduler improves.
func GOMAXPROCS(n int) int { … }

// NumCPU returns the number of logical CPUs usable by the current process.
//
// The set of available CPUs is checked by querying the operating system
// at process startup. Changes to operating system CPU allocation after
// process startup are not reflected.
func NumCPU() int { … }

// NumCgoCall returns the number of cgo calls made by the current process.
func NumCgoCall() int64 { … }

func totalMutexWaitTimeNanos() int64 { … }

// NumGoroutine returns the number of goroutines that currently exist.
func NumGoroutine() int { … }

//go:linkname debug_modinfo runtime/debug.modinfo
func debug_modinfo() string { … }

// mayMoreStackPreempt is a maymorestack hook that forces a preemption
// at every possible cooperative preemption point.
//
// This is valuable to apply to the runtime, which can be sensitive to
// preemption points. To apply this to all preemption points in the
// runtime and runtime-like code, use the following in bash or zsh:
//
//	X=(-{gc,asm}flags={runtime/...,reflect,sync}=-d=maymorestack=runtime.mayMoreStackPreempt) GOFLAGS=${X[@]}
//
// This must be deeply nosplit because it is called from a function
// prologue before the stack is set up and because the compiler will
// call it from any splittable prologue (leading to infinite
// recursion).
//
// Ideally it should also use very little stack because the linker
// doesn't currently account for this in nosplit stack depth checking.
//
// Ensure mayMoreStackPreempt can be called for all ABIs.
//
//go:nosplit
//go:linkname mayMoreStackPreempt
func mayMoreStackPreempt() { … }

// mayMoreStackMove is a maymorestack hook that forces stack movement
// at every possible point.
//
// See mayMoreStackPreempt.
//
//go:nosplit
//go:linkname mayMoreStackMove
func mayMoreStackMove() { … }

var debugPinnerKeepUnpin …

// debugPinnerV1 returns a new Pinner that pins itself. This function can be
// used by debuggers to easily obtain a Pinner that will not be garbage
// collected (or moved in memory) even if no references to it exist in the
// target program. This pinner in turn can be used to extend this property
// to other objects, which debuggers can use to simplify the evaluation of
// expressions involving multiple call injections.
func debugPinnerV1() *Pinner { … }