diff options
Diffstat (limited to 'pkg')
| -rw-r--r-- | pkg/sentry/control/pprof.go | 269 | ||||
| -rw-r--r-- | pkg/urpc/urpc.go | 8 |
2 files changed, 172 insertions, 105 deletions
diff --git a/pkg/sentry/control/pprof.go b/pkg/sentry/control/pprof.go index 91b8fb44f..b78e29416 100644 --- a/pkg/sentry/control/pprof.go +++ b/pkg/sentry/control/pprof.go @@ -15,10 +15,10 @@ package control import ( - "errors" "runtime" "runtime/pprof" "runtime/trace" + "time" "gvisor.dev/gvisor/pkg/fd" "gvisor.dev/gvisor/pkg/sentry/kernel" @@ -26,184 +26,253 @@ import ( "gvisor.dev/gvisor/pkg/urpc" ) -var errNoOutput = errors.New("no output writer provided") +// Profile includes profile-related RPC stubs. It provides a way to +// control the built-in runtime profiling facilities. +// +// The profile object must be instantied via NewProfile. +type Profile struct { + // kernel is the kernel under profile. It's immutable. + kernel *kernel.Kernel -// ProfileOpts contains options for the StartCPUProfile/Goroutine RPC call. -type ProfileOpts struct { - // File is the filesystem path for the profile. - File string `json:"path"` + // cpuMu protects CPU profiling. + cpuMu sync.Mutex - // FilePayload is the destination for the profiling output. - urpc.FilePayload + // blockMu protects block profiling. + blockMu sync.Mutex + + // mutexMu protects mutex profiling. + mutexMu sync.Mutex + + // traceMu protects trace profiling. + traceMu sync.Mutex + + // done is closed when profiling is done. + done chan struct{} } -// Profile includes profile-related RPC stubs. It provides a way to -// control the built-in pprof facility in sentry via sentryctl. -// -// The following options to sentryctl are added: +// NewProfile returns a new Profile object, and a stop callback. // -// - collect CPU profile on-demand. -// sentryctl -pid <pid> pprof-cpu-start -// sentryctl -pid <pid> pprof-cpu-stop -// -// - dump out the stack trace of current go routines. -// sentryctl -pid <pid> pprof-goroutine -type Profile struct { - // Kernel is the kernel under profile. It's immutable. - Kernel *kernel.Kernel +// The stop callback should be used at most once. +func NewProfile(k *kernel.Kernel) (*Profile, func()) { + p := &Profile{ + kernel: k, + done: make(chan struct{}), + } + return p, func() { + close(p.done) + } +} - // mu protects the fields below. - mu sync.Mutex +// CPUProfileOpts contains options specifically for CPU profiles. +type CPUProfileOpts struct { + // FilePayload is the destination for the profiling output. + urpc.FilePayload - // cpuFile is the current CPU profile output file. - cpuFile *fd.FD + // Duration is the duration of the profile. + Duration time.Duration `json:"duration"` - // traceFile is the current execution trace output file. - traceFile *fd.FD + // Hz is the rate, which may be zero. + Hz int `json:"hz"` } -// StartCPUProfile is an RPC stub which starts recording the CPU profile in a -// file. -func (p *Profile) StartCPUProfile(o *ProfileOpts, _ *struct{}) error { +// CPU is an RPC stub which collects a CPU profile. +func (p *Profile) CPU(o *CPUProfileOpts, _ *struct{}) error { if len(o.FilePayload.Files) < 1 { - return errNoOutput + return nil // Allowed. } output, err := fd.NewFromFile(o.FilePayload.Files[0]) if err != nil { return err } + defer output.Close() - p.mu.Lock() - defer p.mu.Unlock() + p.cpuMu.Lock() + defer p.cpuMu.Unlock() // Returns an error if profiling is already started. + if o.Hz != 0 { + runtime.SetCPUProfileRate(o.Hz) + } if err := pprof.StartCPUProfile(output); err != nil { - output.Close() return err } + defer pprof.StopCPUProfile() - p.cpuFile = output - return nil -} - -// StopCPUProfile is an RPC stub which stops the CPU profiling and flush out the -// profile data. It takes no argument. -func (p *Profile) StopCPUProfile(_, _ *struct{}) error { - p.mu.Lock() - defer p.mu.Unlock() - - if p.cpuFile == nil { - return errors.New("CPU profiling not started") + // Collect the profile. + select { + case <-time.After(o.Duration): + case <-p.done: } - pprof.StopCPUProfile() - p.cpuFile.Close() - p.cpuFile = nil return nil } -// HeapProfile generates a heap profile for the sentry. -func (p *Profile) HeapProfile(o *ProfileOpts, _ *struct{}) error { +// HeapProfileOpts contains options specifically for heap profiles. +type HeapProfileOpts struct { + // FilePayload is the destination for the profiling output. + urpc.FilePayload +} + +// Heap generates a heap profile. +func (p *Profile) Heap(o *HeapProfileOpts, _ *struct{}) error { if len(o.FilePayload.Files) < 1 { - return errNoOutput + return nil // Allowed. } + output := o.FilePayload.Files[0] defer output.Close() + runtime.GC() // Get up-to-date statistics. - if err := pprof.WriteHeapProfile(output); err != nil { - return err - } - return nil + return pprof.WriteHeapProfile(output) +} + +// GoroutineProfileOpts contains options specifically for goroutine profiles. +type GoroutineProfileOpts struct { + // FilePayload is the destination for the profiling output. + urpc.FilePayload } -// GoroutineProfile is an RPC stub which dumps out the stack trace for all -// running goroutines. -func (p *Profile) GoroutineProfile(o *ProfileOpts, _ *struct{}) error { +// Goroutine dumps out the stack trace for all running goroutines. +func (p *Profile) Goroutine(o *GoroutineProfileOpts, _ *struct{}) error { if len(o.FilePayload.Files) < 1 { - return errNoOutput + return nil // Allowed. } + output := o.FilePayload.Files[0] defer output.Close() - if err := pprof.Lookup("goroutine").WriteTo(output, 2); err != nil { - return err - } - return nil + + return pprof.Lookup("goroutine").WriteTo(output, 2) +} + +// BlockProfileOpts contains options specifically for block profiles. +type BlockProfileOpts struct { + // FilePayload is the destination for the profiling output. + urpc.FilePayload + + // Duration is the duration of the profile. + Duration time.Duration `json:"duration"` + + // Rate is the block profile rate. + Rate int `json:"rate"` } -// BlockProfile is an RPC stub which dumps out the stack trace that led to -// blocking on synchronization primitives. -func (p *Profile) BlockProfile(o *ProfileOpts, _ *struct{}) error { +// Block dumps a blocking profile. +func (p *Profile) Block(o *BlockProfileOpts, _ *struct{}) error { if len(o.FilePayload.Files) < 1 { - return errNoOutput + return nil // Allowed. } + output := o.FilePayload.Files[0] defer output.Close() - if err := pprof.Lookup("block").WriteTo(output, 0); err != nil { - return err + + p.blockMu.Lock() + defer p.blockMu.Unlock() + + // Always set the rate. We then wait to collect a profile at this rate, + // and disable when we're done. + rate := 1 + if o.Rate != 0 { + rate = o.Rate } - return nil + runtime.SetBlockProfileRate(rate) + defer runtime.SetBlockProfileRate(0) + + // Collect the profile. + select { + case <-time.After(o.Duration): + case <-p.done: + } + + return pprof.Lookup("block").WriteTo(output, 0) +} + +// MutexProfileOpts contains options specifically for mutex profiles. +type MutexProfileOpts struct { + // FilePayload is the destination for the profiling output. + urpc.FilePayload + + // Duration is the duration of the profile. + Duration time.Duration `json:"duration"` + + // Fraction is the mutex profile fraction. + Fraction int `json:"fraction"` } -// MutexProfile is an RPC stub which dumps out the stack trace of holders of -// contended mutexes. -func (p *Profile) MutexProfile(o *ProfileOpts, _ *struct{}) error { +// Mutex dumps a mutex profile. +func (p *Profile) Mutex(o *MutexProfileOpts, _ *struct{}) error { if len(o.FilePayload.Files) < 1 { - return errNoOutput + return nil // Allowed. } + output := o.FilePayload.Files[0] defer output.Close() - if err := pprof.Lookup("mutex").WriteTo(output, 0); err != nil { - return err + + p.mutexMu.Lock() + defer p.mutexMu.Unlock() + + // Always set the fraction. + fraction := 1 + if o.Fraction != 0 { + fraction = o.Fraction } - return nil + runtime.SetMutexProfileFraction(fraction) + defer runtime.SetMutexProfileFraction(0) + + // Collect the profile. + select { + case <-time.After(o.Duration): + case <-p.done: + } + + return pprof.Lookup("mutex").WriteTo(output, 0) } -// StartTrace is an RPC stub which starts collection of an execution trace. -func (p *Profile) StartTrace(o *ProfileOpts, _ *struct{}) error { +// TraceProfileOpts contains options specifically for traces. +type TraceProfileOpts struct { + // FilePayload is the destination for the profiling output. + urpc.FilePayload + + // Duration is the duration of the profile. + Duration time.Duration `json:"duration"` +} + +// Trace is an RPC stub which starts collection of an execution trace. +func (p *Profile) Trace(o *TraceProfileOpts, _ *struct{}) error { if len(o.FilePayload.Files) < 1 { - return errNoOutput + return nil // Allowed. } output, err := fd.NewFromFile(o.FilePayload.Files[0]) if err != nil { return err } + defer output.Close() - p.mu.Lock() - defer p.mu.Unlock() + p.traceMu.Lock() + defer p.traceMu.Unlock() // Returns an error if profiling is already started. if err := trace.Start(output); err != nil { output.Close() return err } + defer trace.Stop() // Ensure all trace contexts are registered. - p.Kernel.RebuildTraceContexts() - - p.traceFile = output - return nil -} - -// StopTrace is an RPC stub which stops collection of an ongoing execution -// trace and flushes the trace data. It takes no argument. -func (p *Profile) StopTrace(_, _ *struct{}) error { - p.mu.Lock() - defer p.mu.Unlock() + p.kernel.RebuildTraceContexts() - if p.traceFile == nil { - return errors.New("execution tracing not started") + // Wait for the trace. + select { + case <-time.After(o.Duration): + case <-p.done: } // Similarly to the case above, if tasks have not ended traces, we will // lose information. Thus we need to rebuild the tasks in order to have // complete information. This will not lose information if multiple // traces are overlapping. - p.Kernel.RebuildTraceContexts() + p.kernel.RebuildTraceContexts() - trace.Stop() - p.traceFile.Close() - p.traceFile = nil return nil } diff --git a/pkg/urpc/urpc.go b/pkg/urpc/urpc.go index 13b2ea314..dfd23032c 100644 --- a/pkg/urpc/urpc.go +++ b/pkg/urpc/urpc.go @@ -283,12 +283,10 @@ func (s *Server) handleOne(client *unet.Socket) error { // Client is dead. return err } + if s.afterRPCCallback != nil { + defer s.afterRPCCallback() + } - defer func() { - if s.afterRPCCallback != nil { - s.afterRPCCallback() - } - }() // Explicitly close all these files after the call. // // This is also explicitly a reference to the files after the call, |