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authorLibravatar Daenney <daenney@users.noreply.github.com>2024-03-11 15:34:34 +0100
committerLibravatar GitHub <noreply@github.com>2024-03-11 15:34:34 +0100
commit5e871e81a87a638b07d540c15d1b95608843255d (patch)
tree62db65c7de651bac3d8894f4f70e0fe8de853a5e /vendor/google.golang.org/grpc/internal/idle/idle.go
parent[chore]: Bump github.com/minio/minio-go/v7 from 7.0.67 to 7.0.69 (#2748) (diff)
downloadgotosocial-5e871e81a87a638b07d540c15d1b95608843255d.tar.xz
[chore] Update usage of OTEL libraries (#2725)
* otel to 1.24 * prometheus exporter to 0.46 * bunotel to 1.1.17 Also: * Use schemaless URL for metrics * Add software version to tracing schema
Diffstat (limited to 'vendor/google.golang.org/grpc/internal/idle/idle.go')
-rw-r--r--vendor/google.golang.org/grpc/internal/idle/idle.go175
1 files changed, 76 insertions, 99 deletions
diff --git a/vendor/google.golang.org/grpc/internal/idle/idle.go b/vendor/google.golang.org/grpc/internal/idle/idle.go
index 6c272476e..fe49cb74c 100644
--- a/vendor/google.golang.org/grpc/internal/idle/idle.go
+++ b/vendor/google.golang.org/grpc/internal/idle/idle.go
@@ -26,8 +26,6 @@ import (
"sync"
"sync/atomic"
"time"
-
- "google.golang.org/grpc/grpclog"
)
// For overriding in unit tests.
@@ -39,27 +37,12 @@ var timeAfterFunc = func(d time.Duration, f func()) *time.Timer {
// and exit from idle mode.
type Enforcer interface {
ExitIdleMode() error
- EnterIdleMode() error
-}
-
-// Manager defines the functionality required to track RPC activity on a
-// channel.
-type Manager interface {
- OnCallBegin() error
- OnCallEnd()
- Close()
+ EnterIdleMode()
}
-type noopManager struct{}
-
-func (noopManager) OnCallBegin() error { return nil }
-func (noopManager) OnCallEnd() {}
-func (noopManager) Close() {}
-
-// manager implements the Manager interface. It uses atomic operations to
-// synchronize access to shared state and a mutex to guarantee mutual exclusion
-// in a critical section.
-type manager struct {
+// Manager implements idleness detection and calls the configured Enforcer to
+// enter/exit idle mode when appropriate. Must be created by NewManager.
+type Manager struct {
// State accessed atomically.
lastCallEndTime int64 // Unix timestamp in nanos; time when the most recent RPC completed.
activeCallsCount int32 // Count of active RPCs; -math.MaxInt32 means channel is idle or is trying to get there.
@@ -69,8 +52,7 @@ type manager struct {
// Can be accessed without atomics or mutex since these are set at creation
// time and read-only after that.
enforcer Enforcer // Functionality provided by grpc.ClientConn.
- timeout int64 // Idle timeout duration nanos stored as an int64.
- logger grpclog.LoggerV2
+ timeout time.Duration
// idleMu is used to guarantee mutual exclusion in two scenarios:
// - Opposing intentions:
@@ -88,57 +70,48 @@ type manager struct {
timer *time.Timer
}
-// ManagerOptions is a collection of options used by
-// NewManager.
-type ManagerOptions struct {
- Enforcer Enforcer
- Timeout time.Duration
- Logger grpclog.LoggerV2
+// NewManager creates a new idleness manager implementation for the
+// given idle timeout. It begins in idle mode.
+func NewManager(enforcer Enforcer, timeout time.Duration) *Manager {
+ return &Manager{
+ enforcer: enforcer,
+ timeout: timeout,
+ actuallyIdle: true,
+ activeCallsCount: -math.MaxInt32,
+ }
}
-// NewManager creates a new idleness manager implementation for the
-// given idle timeout.
-func NewManager(opts ManagerOptions) Manager {
- if opts.Timeout == 0 {
- return noopManager{}
+// resetIdleTimerLocked resets the idle timer to the given duration. Called
+// when exiting idle mode or when the timer fires and we need to reset it.
+func (m *Manager) resetIdleTimerLocked(d time.Duration) {
+ if m.isClosed() || m.timeout == 0 || m.actuallyIdle {
+ return
}
- m := &manager{
- enforcer: opts.Enforcer,
- timeout: int64(opts.Timeout),
- logger: opts.Logger,
+ // It is safe to ignore the return value from Reset() because this method is
+ // only ever called from the timer callback or when exiting idle mode.
+ if m.timer != nil {
+ m.timer.Stop()
}
- m.timer = timeAfterFunc(opts.Timeout, m.handleIdleTimeout)
- return m
+ m.timer = timeAfterFunc(d, m.handleIdleTimeout)
}
-// resetIdleTimer resets the idle timer to the given duration. This method
-// should only be called from the timer callback.
-func (m *manager) resetIdleTimer(d time.Duration) {
+func (m *Manager) resetIdleTimer(d time.Duration) {
m.idleMu.Lock()
defer m.idleMu.Unlock()
-
- if m.timer == nil {
- // Only close sets timer to nil. We are done.
- return
- }
-
- // It is safe to ignore the return value from Reset() because this method is
- // only ever called from the timer callback, which means the timer has
- // already fired.
- m.timer.Reset(d)
+ m.resetIdleTimerLocked(d)
}
// handleIdleTimeout is the timer callback that is invoked upon expiry of the
// configured idle timeout. The channel is considered inactive if there are no
// ongoing calls and no RPC activity since the last time the timer fired.
-func (m *manager) handleIdleTimeout() {
+func (m *Manager) handleIdleTimeout() {
if m.isClosed() {
return
}
if atomic.LoadInt32(&m.activeCallsCount) > 0 {
- m.resetIdleTimer(time.Duration(m.timeout))
+ m.resetIdleTimer(m.timeout)
return
}
@@ -148,24 +121,12 @@ func (m *manager) handleIdleTimeout() {
// Set the timer to fire after a duration of idle timeout, calculated
// from the time the most recent RPC completed.
atomic.StoreInt32(&m.activeSinceLastTimerCheck, 0)
- m.resetIdleTimer(time.Duration(atomic.LoadInt64(&m.lastCallEndTime) + m.timeout - time.Now().UnixNano()))
+ m.resetIdleTimer(time.Duration(atomic.LoadInt64(&m.lastCallEndTime)-time.Now().UnixNano()) + m.timeout)
return
}
- // This CAS operation is extremely likely to succeed given that there has
- // been no activity since the last time we were here. Setting the
- // activeCallsCount to -math.MaxInt32 indicates to OnCallBegin() that the
- // channel is either in idle mode or is trying to get there.
- if !atomic.CompareAndSwapInt32(&m.activeCallsCount, 0, -math.MaxInt32) {
- // This CAS operation can fail if an RPC started after we checked for
- // activity at the top of this method, or one was ongoing from before
- // the last time we were here. In both case, reset the timer and return.
- m.resetIdleTimer(time.Duration(m.timeout))
- return
- }
-
- // Now that we've set the active calls count to -math.MaxInt32, it's time to
- // actually move to idle mode.
+ // Now that we've checked that there has been no activity, attempt to enter
+ // idle mode, which is very likely to succeed.
if m.tryEnterIdleMode() {
// Successfully entered idle mode. No timer needed until we exit idle.
return
@@ -174,8 +135,7 @@ func (m *manager) handleIdleTimeout() {
// Failed to enter idle mode due to a concurrent RPC that kept the channel
// active, or because of an error from the channel. Undo the attempt to
// enter idle, and reset the timer to try again later.
- atomic.AddInt32(&m.activeCallsCount, math.MaxInt32)
- m.resetIdleTimer(time.Duration(m.timeout))
+ m.resetIdleTimer(m.timeout)
}
// tryEnterIdleMode instructs the channel to enter idle mode. But before
@@ -185,36 +145,49 @@ func (m *manager) handleIdleTimeout() {
// Return value indicates whether or not the channel moved to idle mode.
//
// Holds idleMu which ensures mutual exclusion with exitIdleMode.
-func (m *manager) tryEnterIdleMode() bool {
+func (m *Manager) tryEnterIdleMode() bool {
+ // Setting the activeCallsCount to -math.MaxInt32 indicates to OnCallBegin()
+ // that the channel is either in idle mode or is trying to get there.
+ if !atomic.CompareAndSwapInt32(&m.activeCallsCount, 0, -math.MaxInt32) {
+ // This CAS operation can fail if an RPC started after we checked for
+ // activity in the timer handler, or one was ongoing from before the
+ // last time the timer fired, or if a test is attempting to enter idle
+ // mode without checking. In all cases, abort going into idle mode.
+ return false
+ }
+ // N.B. if we fail to enter idle mode after this, we must re-add
+ // math.MaxInt32 to m.activeCallsCount.
+
m.idleMu.Lock()
defer m.idleMu.Unlock()
if atomic.LoadInt32(&m.activeCallsCount) != -math.MaxInt32 {
// We raced and lost to a new RPC. Very rare, but stop entering idle.
+ atomic.AddInt32(&m.activeCallsCount, math.MaxInt32)
return false
}
if atomic.LoadInt32(&m.activeSinceLastTimerCheck) == 1 {
- // An very short RPC could have come in (and also finished) after we
+ // A very short RPC could have come in (and also finished) after we
// checked for calls count and activity in handleIdleTimeout(), but
// before the CAS operation. So, we need to check for activity again.
+ atomic.AddInt32(&m.activeCallsCount, math.MaxInt32)
return false
}
- // No new RPCs have come in since we last set the active calls count value
- // -math.MaxInt32 in the timer callback. And since we have the lock, it is
- // safe to enter idle mode now.
- if err := m.enforcer.EnterIdleMode(); err != nil {
- m.logger.Errorf("Failed to enter idle mode: %v", err)
- return false
- }
-
- // Successfully entered idle mode.
+ // No new RPCs have come in since we set the active calls count value to
+ // -math.MaxInt32. And since we have the lock, it is safe to enter idle mode
+ // unconditionally now.
+ m.enforcer.EnterIdleMode()
m.actuallyIdle = true
return true
}
+func (m *Manager) EnterIdleModeForTesting() {
+ m.tryEnterIdleMode()
+}
+
// OnCallBegin is invoked at the start of every RPC.
-func (m *manager) OnCallBegin() error {
+func (m *Manager) OnCallBegin() error {
if m.isClosed() {
return nil
}
@@ -227,7 +200,7 @@ func (m *manager) OnCallBegin() error {
// Channel is either in idle mode or is in the process of moving to idle
// mode. Attempt to exit idle mode to allow this RPC.
- if err := m.exitIdleMode(); err != nil {
+ if err := m.ExitIdleMode(); err != nil {
// Undo the increment to calls count, and return an error causing the
// RPC to fail.
atomic.AddInt32(&m.activeCallsCount, -1)
@@ -238,28 +211,30 @@ func (m *manager) OnCallBegin() error {
return nil
}
-// exitIdleMode instructs the channel to exit idle mode.
-//
-// Holds idleMu which ensures mutual exclusion with tryEnterIdleMode.
-func (m *manager) exitIdleMode() error {
+// ExitIdleMode instructs m to call the enforcer's ExitIdleMode and update m's
+// internal state.
+func (m *Manager) ExitIdleMode() error {
+ // Holds idleMu which ensures mutual exclusion with tryEnterIdleMode.
m.idleMu.Lock()
defer m.idleMu.Unlock()
- if !m.actuallyIdle {
- // This can happen in two scenarios:
+ if m.isClosed() || !m.actuallyIdle {
+ // This can happen in three scenarios:
// - handleIdleTimeout() set the calls count to -math.MaxInt32 and called
// tryEnterIdleMode(). But before the latter could grab the lock, an RPC
// came in and OnCallBegin() noticed that the calls count is negative.
// - Channel is in idle mode, and multiple new RPCs come in at the same
// time, all of them notice a negative calls count in OnCallBegin and get
// here. The first one to get the lock would got the channel to exit idle.
+ // - Channel is not in idle mode, and the user calls Connect which calls
+ // m.ExitIdleMode.
//
- // Either way, nothing to do here.
+ // In any case, there is nothing to do here.
return nil
}
if err := m.enforcer.ExitIdleMode(); err != nil {
- return fmt.Errorf("channel failed to exit idle mode: %v", err)
+ return fmt.Errorf("failed to exit idle mode: %w", err)
}
// Undo the idle entry process. This also respects any new RPC attempts.
@@ -267,12 +242,12 @@ func (m *manager) exitIdleMode() error {
m.actuallyIdle = false
// Start a new timer to fire after the configured idle timeout.
- m.timer = timeAfterFunc(time.Duration(m.timeout), m.handleIdleTimeout)
+ m.resetIdleTimerLocked(m.timeout)
return nil
}
// OnCallEnd is invoked at the end of every RPC.
-func (m *manager) OnCallEnd() {
+func (m *Manager) OnCallEnd() {
if m.isClosed() {
return
}
@@ -287,15 +262,17 @@ func (m *manager) OnCallEnd() {
atomic.AddInt32(&m.activeCallsCount, -1)
}
-func (m *manager) isClosed() bool {
+func (m *Manager) isClosed() bool {
return atomic.LoadInt32(&m.closed) == 1
}
-func (m *manager) Close() {
+func (m *Manager) Close() {
atomic.StoreInt32(&m.closed, 1)
m.idleMu.Lock()
- m.timer.Stop()
- m.timer = nil
+ if m.timer != nil {
+ m.timer.Stop()
+ m.timer = nil
+ }
m.idleMu.Unlock()
}