CLFLUSH（）的酷睿i3或者i7处理器 [英] clflush() in i3 or i7 processors

问题描述

是否有可能使用的i3 / i7处理器的指令CLFLUSH /功能清空缓存并检查是否缓存为空或不？如果是这样的 - 请建议用法的正确格式（在C直接或内联汇编在C）

Is it possible to use the clflush instruction/function in i3/i7 processors to the flush the cache and check if the cache is empty or not?? If so - please suggest a correct format of usage (in C directly or inline assembly in C)

有人告诉我，CLFLUSH不正常工作超越Core 2 Duo处理器。
我从这个链接（如下）已经被重定向后，说明了这个问题------->

I was told that clflush does work properly beyond core 2 duo processors. I am stating this question after having been redirected from this link (below) ------->

¨<一个href=\"http://stackoverflow.com/questions/6041271/is-there-a-way-to-check-whether-the-processor-cache-has-been-flushed-recently\">Is有没有办法来检查是否处理器高速缓存最近被刷新？¨

我的结果不匹配。这是我得到的结果：

my results are not matching as expected. This is what I am getting these results:

83花蜱

的花了66蜱的

的刷新：52花蜱的

用了45蜱

-------------------> cpu的怎么能少取蜱已经清空缓存后？ （参考线2条，而且我已经得到的结果3）

-------------------> how can the cpu take less ticks after having flushed the cache? (refer to line 2 and 3 of the results that i have gotten)

推荐答案

RDTSC 不是序列化指令，因为这样的测量结果不准确。作为一个快速黑客可以插入 CPUID 通话，照顾太多更新撞列表：

rdtsc isn't a serializing instruction, as such the measurement is not accurate. As a quick hack you can insert a cpuid call, taking care to update the clobber list too:

asm volatile ("cpuid; rdtsc" : "=a" (a), "=d" (d) : : "ebx", "ecx");

至少对我来说，改变了输出以符合预期。

At least for me, that changed the output to match expectations.

这篇关于CLFLUSH（）的酷睿i3或者i7处理器的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！