Messages in this thread | | | From | Denys Vlasenko <> | Subject | Re: [PATCH] i386: Fix a couple busy loops in mach_wakecpu.h:wait_for_init_deassert() | Date | Fri, 24 Aug 2007 12:59:32 +0100 |
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On Thursday 16 August 2007 01:39, Satyam Sharma wrote: > > static inline void wait_for_init_deassert(atomic_t *deassert) > { > - while (!atomic_read(deassert)); > + while (!atomic_read(deassert)) > + cpu_relax(); > return; > }
For less-than-briliant people like me, it's totally non-obvious that cpu_relax() is needed for correctness here, not just to make P4 happy.
IOW: "atomic_read" name quite unambiguously means "I will read this variable from main memory". Which is not true and creates potential for confusion and bugs. -- vda - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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