Module mcslock::barging

Available on crate feature barging only.

A barging MCS lock implementation that is compliant with the lock_api crate.

This implementation will have non-waiting threads race for the lock against the front of the waiting queue thread. If the front of the queue thread looses the race, it will simply keep spinning, while holding its position in the queue. By allowing barging instead of forcing FIFO, a higher throughput can be achieved when the lock is heavily contended. This implementation is suitable for no_std environments, and the locking APIs are compatible with the lock_api crate (see lock_api feature).

The lock is hold for as long as its associated RAII guard is in scope. Once the guard is dropped, the mutex is freed. Mutex guards are returned by lock and try_lock. Guards are also accessible as the closure argument for lock_with and try_lock_with methods.

The Mutex is generic over the relax strategy. User may choose a strategy as long as it implements the Relax trait. There is a number of strategies provided by the relax module. Each submodule provides type aliases for Mutex and MutexGuard associated with one relax strategy. See their documentation for more information.

Modules

• loops
  A barging MCS lock alias that rapidly spins without telling the CPU to do any power down during lock contention.
• spins
  A barging MCS lock alias that signals the processor that it is running a busy-wait spin-loop during lock contention.
• yieldsyield
  A barging MCS lock alias that yields the current time slice to the OS scheduler during lock contention.

Structs

• Mutex
  A mutual exclusion primitive useful for protecting shared data.
• MutexGuard
  An RAII implementation of a “scoped lock” of a mutex. When this structure is dropped (falls out of scope), the lock will be unlocked.