Messages in this thread | | | Subject | Re: [patch] spinlocks: remove 'volatile' | From | Arjan van de Ven <> | Date | Sat, 08 Jul 2006 08:58:44 +0200 |
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> > __forceinline void Lock(volatile LONG *hPtr) > { > int iValue; > > for (;;) { > iValue = _InterlockedExchange((LPLONG)hPtr, 1); > if (iValue == 0) > return; > while (*hPtr); > } > } > > Please show me how I can write this to spinlock without using volatile.
this code is broken, at the very minimum that while (*hPtr); needs to be "while (*hPtr) cpu_relax();" for hardware reasons. At which point you can drop the volatile entirely without any change.
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