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H. Peter Anvin a écrit : > Eric Dumazet wrote: >> >> There is one thing that always worried me. >> >> Intel & AMD manuals make clear that mixing data and program in the >> same page is bad for performance. >> >> In particular, x86_64 vsyscall put jiffies and other >> vsyscall_gtod_data_t right in the midle of code. That is certainly not >> wise. >> >> A probably sane implementation should use two pages, one for code, one >> for data. >> > > Mutable data should be separated from code. I think any current CPU > will do fine as long as they are in separate 128-byte chunks, but they > need at least that much separation. > > Readonly data does not need to be separated from code. > Yes... jiffies & vsyscall_gtod_data_t is writen HZ times per second. Not really readonly I'm afraid. - 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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