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    arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c: avoid cross-CPU interrupts by... · 4a28395d
    Andrew Morton authored
    arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c: avoid cross-CPU interrupts by using smp_call_function_any()
    
    Presently acpi-cpufreq will perform the MSR read on the first CPU in the
    mask.  That's inefficient if that CPU differs from the current CPU.
    Because we have to perform a cross-CPU call, but we could have run the
    rdmsr on the current CPU.
    
    So switch to using the new smp_call_function_any(), which will perform the
    call on the current CPU if that CPU is present in the mask (it is).
    
    Cc: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
    Cc: Dave Jones <davej@redhat.com>
    Cc: Ingo Molnar <mingo@elte.hu>
    Cc: Jaswinder Singh Rajput <jaswinder@kernel.org>
    Cc: Len Brown <len.brown@intel.com>
    Cc: Mike Galbraith <efault@gmx.de>
    Cc: Rusty Russell <rusty@rustcorp.com.au>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Cc: Zhao Yakui <yakui.zhao@intel.com>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLen Brown <len.brown@intel.com>
    4a28395d
acpi-cpufreq.c 20.5 KB