pub fn spin_loop()
Expand description
Emits a machine instruction to signal the processor that it is running in a busy-wait spin-loop (“spin lock”).
Upon receiving the spin-loop signal the processor can optimize its behavior by, for example, saving power or switching hyper-threads.
This function is different from thread::yield_now
which directly
yields to the system’s scheduler, whereas spin_loop
does not interact
with the operating system.
A common use case for spin_loop
is implementing bounded optimistic
spinning in a CAS loop in synchronization primitives. To avoid problems
like priority inversion, it is strongly recommended that the spin loop is
terminated after a finite amount of iterations and an appropriate blocking
syscall is made.
Note: On platforms that do not support receiving spin-loop hints this function does not do anything at all.