mirror of
https://codeberg.org/forgejo/forgejo.git
synced 2024-12-27 08:42:14 +01:00
79394b340d
The graceful manager has some bugs (#27643, #28062). This is a preparation for further fixes.
257 lines
7 KiB
Go
257 lines
7 KiB
Go
// Copyright 2019 The Gitea Authors. All rights reserved.
|
|
// SPDX-License-Identifier: MIT
|
|
|
|
package graceful
|
|
|
|
import (
|
|
"context"
|
|
"runtime/pprof"
|
|
"sync"
|
|
"time"
|
|
|
|
"code.gitea.io/gitea/modules/log"
|
|
"code.gitea.io/gitea/modules/process"
|
|
"code.gitea.io/gitea/modules/setting"
|
|
)
|
|
|
|
type state uint8
|
|
|
|
const (
|
|
stateInit state = iota
|
|
stateRunning
|
|
stateShuttingDown
|
|
stateTerminate
|
|
)
|
|
|
|
type RunCanceler interface {
|
|
Run()
|
|
Cancel()
|
|
}
|
|
|
|
// There are some places that could inherit sockets:
|
|
//
|
|
// * HTTP or HTTPS main listener
|
|
// * HTTP or HTTPS install listener
|
|
// * HTTP redirection fallback
|
|
// * Builtin SSH listener
|
|
//
|
|
// If you add a new place you must increment this number
|
|
// and add a function to call manager.InformCleanup if it's not going to be used
|
|
const numberOfServersToCreate = 4
|
|
|
|
var (
|
|
manager *Manager
|
|
initOnce sync.Once
|
|
)
|
|
|
|
// GetManager returns the Manager
|
|
func GetManager() *Manager {
|
|
InitManager(context.Background())
|
|
return manager
|
|
}
|
|
|
|
// InitManager creates the graceful manager in the provided context
|
|
func InitManager(ctx context.Context) {
|
|
initOnce.Do(func() {
|
|
manager = newGracefulManager(ctx)
|
|
|
|
// Set the process default context to the HammerContext
|
|
process.DefaultContext = manager.HammerContext()
|
|
})
|
|
}
|
|
|
|
// RunWithCancel helps to run a function with a custom context, the Cancel function will be called at shutdown
|
|
// The Cancel function should stop the Run function in predictable time.
|
|
func (g *Manager) RunWithCancel(rc RunCanceler) {
|
|
g.RunAtShutdown(context.Background(), rc.Cancel)
|
|
g.runningServerWaitGroup.Add(1)
|
|
defer g.runningServerWaitGroup.Done()
|
|
defer func() {
|
|
if err := recover(); err != nil {
|
|
log.Critical("PANIC during RunWithCancel: %v\nStacktrace: %s", err, log.Stack(2))
|
|
g.doShutdown()
|
|
}
|
|
}()
|
|
rc.Run()
|
|
}
|
|
|
|
// RunWithShutdownContext takes a function that has a context to watch for shutdown.
|
|
// After the provided context is Done(), the main function must return once shutdown is complete.
|
|
// (Optionally the HammerContext may be obtained and waited for however, this should be avoided if possible.)
|
|
func (g *Manager) RunWithShutdownContext(run func(context.Context)) {
|
|
g.runningServerWaitGroup.Add(1)
|
|
defer g.runningServerWaitGroup.Done()
|
|
defer func() {
|
|
if err := recover(); err != nil {
|
|
log.Critical("PANIC during RunWithShutdownContext: %v\nStacktrace: %s", err, log.Stack(2))
|
|
g.doShutdown()
|
|
}
|
|
}()
|
|
ctx := g.ShutdownContext()
|
|
pprof.SetGoroutineLabels(ctx) // We don't have a label to restore back to but I think this is fine
|
|
run(ctx)
|
|
}
|
|
|
|
// RunAtTerminate adds to the terminate wait group and creates a go-routine to run the provided function at termination
|
|
func (g *Manager) RunAtTerminate(terminate func()) {
|
|
g.terminateWaitGroup.Add(1)
|
|
g.lock.Lock()
|
|
defer g.lock.Unlock()
|
|
g.toRunAtTerminate = append(g.toRunAtTerminate,
|
|
func() {
|
|
defer g.terminateWaitGroup.Done()
|
|
defer func() {
|
|
if err := recover(); err != nil {
|
|
log.Critical("PANIC during RunAtTerminate: %v\nStacktrace: %s", err, log.Stack(2))
|
|
}
|
|
}()
|
|
terminate()
|
|
})
|
|
}
|
|
|
|
// RunAtShutdown creates a go-routine to run the provided function at shutdown
|
|
func (g *Manager) RunAtShutdown(ctx context.Context, shutdown func()) {
|
|
g.lock.Lock()
|
|
defer g.lock.Unlock()
|
|
g.toRunAtShutdown = append(g.toRunAtShutdown,
|
|
func() {
|
|
defer func() {
|
|
if err := recover(); err != nil {
|
|
log.Critical("PANIC during RunAtShutdown: %v\nStacktrace: %s", err, log.Stack(2))
|
|
}
|
|
}()
|
|
select {
|
|
case <-ctx.Done():
|
|
return
|
|
default:
|
|
shutdown()
|
|
}
|
|
})
|
|
}
|
|
|
|
func (g *Manager) doShutdown() {
|
|
if !g.setStateTransition(stateRunning, stateShuttingDown) {
|
|
g.DoImmediateHammer()
|
|
return
|
|
}
|
|
g.lock.Lock()
|
|
g.shutdownCtxCancel()
|
|
atShutdownCtx := pprof.WithLabels(g.hammerCtx, pprof.Labels("graceful-lifecycle", "post-shutdown"))
|
|
pprof.SetGoroutineLabels(atShutdownCtx)
|
|
for _, fn := range g.toRunAtShutdown {
|
|
go fn()
|
|
}
|
|
g.lock.Unlock()
|
|
|
|
if setting.GracefulHammerTime >= 0 {
|
|
go g.doHammerTime(setting.GracefulHammerTime)
|
|
}
|
|
go func() {
|
|
g.runningServerWaitGroup.Wait()
|
|
// Mop up any remaining unclosed events.
|
|
g.doHammerTime(0)
|
|
<-time.After(1 * time.Second)
|
|
g.doTerminate()
|
|
g.terminateWaitGroup.Wait()
|
|
g.lock.Lock()
|
|
g.managerCtxCancel()
|
|
g.lock.Unlock()
|
|
}()
|
|
}
|
|
|
|
func (g *Manager) doHammerTime(d time.Duration) {
|
|
time.Sleep(d)
|
|
g.lock.Lock()
|
|
select {
|
|
case <-g.hammerCtx.Done():
|
|
default:
|
|
log.Warn("Setting Hammer condition")
|
|
g.hammerCtxCancel()
|
|
atHammerCtx := pprof.WithLabels(g.terminateCtx, pprof.Labels("graceful-lifecycle", "post-hammer"))
|
|
pprof.SetGoroutineLabels(atHammerCtx)
|
|
}
|
|
g.lock.Unlock()
|
|
}
|
|
|
|
func (g *Manager) doTerminate() {
|
|
if !g.setStateTransition(stateShuttingDown, stateTerminate) {
|
|
return
|
|
}
|
|
g.lock.Lock()
|
|
select {
|
|
case <-g.terminateCtx.Done():
|
|
default:
|
|
log.Warn("Terminating")
|
|
g.terminateCtxCancel()
|
|
atTerminateCtx := pprof.WithLabels(g.managerCtx, pprof.Labels("graceful-lifecycle", "post-terminate"))
|
|
pprof.SetGoroutineLabels(atTerminateCtx)
|
|
|
|
for _, fn := range g.toRunAtTerminate {
|
|
go fn()
|
|
}
|
|
}
|
|
g.lock.Unlock()
|
|
}
|
|
|
|
// IsChild returns if the current process is a child of previous Gitea process
|
|
func (g *Manager) IsChild() bool {
|
|
return g.isChild
|
|
}
|
|
|
|
// IsShutdown returns a channel which will be closed at shutdown.
|
|
// The order of closure is shutdown, hammer (potentially), terminate
|
|
func (g *Manager) IsShutdown() <-chan struct{} {
|
|
return g.shutdownCtx.Done()
|
|
}
|
|
|
|
// IsHammer returns a channel which will be closed at hammer.
|
|
// Servers running within the running server wait group should respond to IsHammer
|
|
// if not shutdown already
|
|
func (g *Manager) IsHammer() <-chan struct{} {
|
|
return g.hammerCtx.Done()
|
|
}
|
|
|
|
// ServerDone declares a running server done and subtracts one from the
|
|
// running server wait group. Users probably do not want to call this
|
|
// and should use one of the RunWithShutdown* functions
|
|
func (g *Manager) ServerDone() {
|
|
g.runningServerWaitGroup.Done()
|
|
}
|
|
|
|
func (g *Manager) setStateTransition(old, new state) bool {
|
|
g.lock.Lock()
|
|
if g.state != old {
|
|
g.lock.Unlock()
|
|
return false
|
|
}
|
|
g.state = new
|
|
g.lock.Unlock()
|
|
return true
|
|
}
|
|
|
|
// InformCleanup tells the cleanup wait group that we have either taken a listener or will not be taking a listener.
|
|
// At the moment the total number of servers (numberOfServersToCreate) are pre-defined as a const before global init,
|
|
// so this function MUST be called if a server is not used.
|
|
func (g *Manager) InformCleanup() {
|
|
g.createServerWaitGroup.Done()
|
|
}
|
|
|
|
// Done allows the manager to be viewed as a context.Context, it returns a channel that is closed when the server is finished terminating
|
|
func (g *Manager) Done() <-chan struct{} {
|
|
return g.managerCtx.Done()
|
|
}
|
|
|
|
// Err allows the manager to be viewed as a context.Context done at Terminate
|
|
func (g *Manager) Err() error {
|
|
return g.managerCtx.Err()
|
|
}
|
|
|
|
// Value allows the manager to be viewed as a context.Context done at Terminate
|
|
func (g *Manager) Value(key any) any {
|
|
return g.managerCtx.Value(key)
|
|
}
|
|
|
|
// Deadline returns nil as there is no fixed Deadline for the manager, it allows the manager to be viewed as a context.Context
|
|
func (g *Manager) Deadline() (deadline time.Time, ok bool) {
|
|
return g.managerCtx.Deadline()
|
|
}
|