Avoid the call to check_freq() by default, since that function may spin
up to 1ms on certain systems without indicating any kind of severe
failure. This matches similar behavior in Linux.
Avoid doing a cross processor call in get_cur_val() if the current CPU
has its bit set in the mask passed in. Also use the local variable
''cpu'' consistently, allowing to remove another local variable.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
--- 2009-01-30.orig/xen/arch/x86/acpi/cpufreq/cpufreq.c 2009-01-08
10:30:05.000000000 +0100
+++ 2009-01-30/xen/arch/x86/acpi/cpufreq/cpufreq.c 2009-02-03 16:20:02.000000000
+0100
@@ -58,6 +58,9 @@ static struct acpi_cpufreq_data *drv_dat
static struct cpufreq_driver acpi_cpufreq_driver;
+static unsigned int __read_mostly acpi_pstate_strict;
+integer_param("acpi_pstate_strict", acpi_pstate_strict);
+
static int check_est_cpu(unsigned int cpuid)
{
struct cpuinfo_x86 *cpu = &cpu_data[cpuid];
@@ -193,28 +196,27 @@ static void drv_write(struct drv_cmd *cm
static u32 get_cur_val(cpumask_t mask)
{
- struct cpufreq_policy *policy;
struct processor_performance *perf;
struct drv_cmd cmd;
- unsigned int cpu;
+ unsigned int cpu = smp_processor_id();
if (unlikely(cpus_empty(mask)))
return 0;
- cpu = first_cpu(mask);
- policy = cpufreq_cpu_policy[cpu];
+ if (!cpu_isset(cpu, mask))
+ cpu = first_cpu(mask);
- if (!policy)
+ if (cpu >= NR_CPUS || !drv_data[cpu])
return 0;
- switch (drv_data[policy->cpu]->cpu_feature) {
+ switch (drv_data[cpu]->cpu_feature) {
case SYSTEM_INTEL_MSR_CAPABLE:
cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
cmd.addr.msr.reg = MSR_IA32_PERF_STATUS;
break;
case SYSTEM_IO_CAPABLE:
cmd.type = SYSTEM_IO_CAPABLE;
- perf = drv_data[first_cpu(mask)]->acpi_data;
+ perf = drv_data[cpu]->acpi_data;
cmd.addr.io.port = perf->control_register.address;
cmd.addr.io.bit_width = perf->control_register.bit_width;
break;
@@ -393,7 +395,7 @@ static int acpi_cpufreq_target(struct cp
drv_write(&cmd);
- if (!check_freqs(cmd.mask, freqs.new, data)) {
+ if (acpi_pstate_strict && !check_freqs(cmd.mask, freqs.new, data))
{
printk(KERN_WARNING "Fail transfer to new freq %d\n",
freqs.new);
return -EAGAIN;
}
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