Package singleflight provides a duplicate function call suppression mechanism.

DeadlockEnabled is true if the deadlock detector is enabled.

LogExpensiveLogEnabled is injected from pkg/util/log to avoid an import cycle.

LogVEventfDepth is injected from pkg/util/log to avoid an import cycle.

AtomicFloat64 mimics the atomic types in the sync/atomic standard library, but for the float64 type.

AtomicString gives you atomic-style APIs for string.

Map is like a Go map[K]*V but is safe for concurrent use by multiple goroutines without additional locking or coordination.

A Mutex is a mutual exclusion lock.

An RWMutex is a reader/writer mutual exclusion lock.

Set is like a Go map[V]struct{} but is safe for concurrent use by multiple goroutines without additional locking or coordination.