x86: add clflush before monitor for Intel 7400 series

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For Intel 7400 series CPUs, the recommendation is to use a clflush on the
monitored address just before monitor and mwait pair [1].

This clflush makes sure that there are no false wakeups from mwait when the
monitored address was recently written to.

[1] "MONITOR/MWAIT Recommendations for Intel Xeon Processor 7400 series"
    section in specification update document of 7400 series
    http://download.intel.com/design/xeon/specupdt/32033601.pdf

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

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Pallipadi, Venkatesh 2009-02-06 16:52:05 -08:00 • committed by Ingo Molnar

parent 0cd5c3c80a

commit e736ad548d

3 changed files with 10 additions and 0 deletions

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1

arch/x86/include/asm/cpufeature.h

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arch/x86/kernel/cpu/intel.c

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6

arch/x86/kernel/process.c

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