Spinlock naming resolved

tglx — Thu, 17 Dec 2009 22:40:27 +0000

Just for clarification:

We renamed the architecture implementations from raw_spinlock to arch_spinlock. This freed the raw_spinlock name space for the "real" spinlocks.

So the new scheme is:

spinlock - the weakest one, which might sleep in RT

raw_spinlock - spinlock which always spins even on RT

arch_spinlock - the hardware level architecture dependent implementation

We have separate functions for all three types as well, which follow the same name space conventions. spin_*(), raw_spin_*() and arch_spin_*().

With PREEMPT_RT=n (which is current mainline) the spinlock functions map to raw_spinlock functions, but the name space is kept separate even at the variable type level. raw_spin_lock(&spinlock) will result in a warning as well as spin_lock(&raw_spinlock). The warning in mainline is harmless as the data structures are identical, but on RT it's going to fatal.

Thanks,

tglx

Spinlock naming resolved

knobunc — Thu, 10 Dec 2009 19:27:59 +0000

The name also has the implication of an extreme form of a spinlock. Like archenemy and enemy.

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Spinlock naming resolved

Spinlock naming resolved