linux/arch/x86_64
Venkatesh Pallipadi 95235ca2c2 [CPUFREQ] CPU frequency display in /proc/cpuinfo
What is the value shown in "cpu MHz" of /proc/cpuinfo when CPUs are capable of
changing frequency?

Today the answer is: It depends.
On i386:
SMP kernel - It is always the boot frequency
UP kernel - Scales with the frequency change and shows that was last set.

On x86_64:
There is one single variable cpu_khz that gets written by all the CPUs. So,
the frequency set by last CPU will be seen on /proc/cpuinfo of all the
CPUs in the system. What you see also depends on whether you have constant_tsc
capable CPU or not.

On ia64:
It is always boot time frequency of a particular CPU that gets displayed.

The patch below changes this to:
Show the last known frequency of the particular CPU, when cpufreq is present. If
cpu doesnot support changing of frequency through cpufreq, then boot frequency
will be shown. The patch affects i386, x86_64 and ia64 architectures.

Signed-off-by: Venkatesh Pallipadi<venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2005-12-06 19:35:11 -08:00
..
boot [PATCH] x86-64: Fix gcc 4 warnings about pointer signedness 2005-09-12 10:50:56 -07:00
crypto [PATCH] x86_64: add MODULE_ALIAS for aes 2005-08-08 15:29:13 -07:00
ia32 Merge x86-64 update from Andi 2005-11-14 19:56:02 -08:00
kernel [CPUFREQ] CPU frequency display in /proc/cpuinfo 2005-12-06 19:35:11 -08:00
lib [PATCH] x86_64: Remove optimization for B stepping AMD K8 2005-11-14 19:55:17 -08:00
mm [PATCH] x86_64: Fix sparse mem 2005-11-14 19:55:18 -08:00
oprofile [PATCH] Move Kprobes and Oprofile to "Instrumentation Support" menu 2005-11-07 07:53:35 -08:00
pci [PATCH] x86-64: Use ACPI PXM to parse PCI<->node assignments 2005-09-12 10:49:57 -07:00
defconfig [PATCH] x86_64: Update defconfig 2005-11-14 19:55:12 -08:00
Kconfig Merge x86-64 update from Andi 2005-11-14 19:56:02 -08:00
Kconfig.debug Merge x86-64 update from Andi 2005-11-14 19:56:02 -08:00
Makefile kbuild: alpha,x86_64 use generic asm-offsets.h support 2005-09-09 21:28:48 +02:00