arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c: avoid cross-CPU interrupts by using smp_c...
authorAndrew Morton <akpm@linux-foundation.org>
Tue, 22 Dec 2009 00:19:58 +0000 (16:19 -0800)
committerLen Brown <len.brown@intel.com>
Tue, 22 Dec 2009 20:03:57 +0000 (15:03 -0500)
commit4a28395d72a956f2dad24e343d06bc08c9afb89a
tree37418b244175d017061bb4aef257c379dce859f4
parent55639353a0035052d9ea6cfe4dde0ac7fcbb2c9f
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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c