[PATCH 0/4] improve alternative instruction code and optimize get_cycles_sync

From: "Joerg Roedel" <joerg.roedel@xxxxxxx>
Date: Wed, 28 Feb 2007 15:05:01 +0100

This series of patches extend the alternative instructions framework on
i386 and x86_64 architectures to support two alternative instruction
replacements. This code is used together with the introduction of the
X86_FEATURE_SYNC_RDTSC flag on i386 to simplify and optimize the
get_cycles_sync() function. The optimization changes this function to
use RDTSCP instead of CPUID;RDTSC if this instruction is available.
Don't use CPUID there is really important if the kernel runs as a KVM
guest, because this instruction is intercepted and causes an expensive
VMEXIT.

--
Joerg Roedel
Operating System Research Center
AMD Saxony LLC & Co. KG

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Follow-Ups:
- [PATCH 4/4] optimize and simplify get_cycles_sync()
  - From: Joerg Roedel
- [PATCH 3/4] i386: add the X86_FEATURE_SYNC_RDTSC flag
  - From: Joerg Roedel
- [PATCH 2/4] x86_64: changes to x86_64 architecture for alternative instruction improvements
  - From: Joerg Roedel
- [PATCH 1/4] i386: extend alternative instructions framework
  - From: Joerg Roedel

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Relevant Pages

[PATCH 0/3] extend alternative instruction framework to support more than one alternative
... this small series of patches extend the alternative instructions ...
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[PATCH 0/4 TRY#3] improve alternative instruction code and optimize get_cycles_sync
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