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cpumask: use work_on_cpu in acpi/cstate.c 

Impact: use new cpumask API to reduce stack usage

Replace the saving of current->cpus_allowed and set_cpus_allowed_ptr() with
a work_on_cpu function for the acpi_processor_ffh_cstate_probe() function.

Basically splits acpi_processor_ffh_cstate_probe() into two functions, the
other being acpi_processor_ffh_cstate_probe_cpu which is the work function
run on the designated cpu.

Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Mike Travis 2009-01-04 05:18:07 -08:00 committed by Ingo Molnar
parent 835481d9bc
commit c74f31c035
1 changed files with 37 additions and 33 deletions
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70
arch/x86/kernel/acpi/cstate.c
View File

@ -66,35 +66,15 @@ static short mwait_supported[ACPI_PROCESSOR_MAX_POWER];
#define NATIVE_CSTATE_BEYOND_HALT (2)
int acpi_processor_ffh_cstate_probe(unsigned int cpu,
struct acpi_processor_cx *cx, struct acpi_power_register *reg)
static long acpi_processor_ffh_cstate_probe_cpu(void *_cx)
{
struct cstate_entry *percpu_entry;
struct cpuinfo_x86 *c = &cpu_data(cpu);
cpumask_t saved_mask;
int retval;
struct acpi_processor_cx *cx = _cx;
long retval;
unsigned int eax, ebx, ecx, edx;
unsigned int edx_part;
unsigned int cstate_type; /* C-state type and not ACPI C-state type */
unsigned int num_cstate_subtype;
if (!cpu_cstate_entry || c->cpuid_level < CPUID_MWAIT_LEAF )
return -1;
if (reg->bit_offset != NATIVE_CSTATE_BEYOND_HALT)
return -1;
percpu_entry = per_cpu_ptr(cpu_cstate_entry, cpu);
percpu_entry->states[cx->index].eax = 0;
percpu_entry->states[cx->index].ecx = 0;
/* Make sure we are running on right CPU */
saved_mask = current->cpus_allowed;
retval = set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu));
if (retval)
return -1;
cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &edx);
/* Check whether this particular cx_type (in CST) is supported or not */
@ -114,21 +94,45 @@ int acpi_processor_ffh_cstate_probe(unsigned int cpu,
retval = -1;
goto out;
}
percpu_entry->states[cx->index].ecx = MWAIT_ECX_INTERRUPT_BREAK;
/* Use the hint in CST */
percpu_entry->states[cx->index].eax = cx->address;
if (!mwait_supported[cstate_type]) {
mwait_supported[cstate_type] = 1;
printk(KERN_DEBUG "Monitor-Mwait will be used to enter C-%d "
"state\n", cx->type);
printk(KERN_DEBUG
"Monitor-Mwait will be used to enter C-%d "
"state\n", cx->type);
}
snprintf(cx->desc, ACPI_CX_DESC_LEN, "ACPI FFH INTEL MWAIT 0x%x",
cx->address);
snprintf(cx->desc,
ACPI_CX_DESC_LEN, "ACPI FFH INTEL MWAIT 0x%x",
cx->address);
out:
set_cpus_allowed_ptr(current, &saved_mask);
return retval;
}
int acpi_processor_ffh_cstate_probe(unsigned int cpu,
struct acpi_processor_cx *cx, struct acpi_power_register *reg)
{
struct cstate_entry *percpu_entry;
struct cpuinfo_x86 *c = &cpu_data(cpu);
long retval;
if (!cpu_cstate_entry || c->cpuid_level < CPUID_MWAIT_LEAF)
return -1;
if (reg->bit_offset != NATIVE_CSTATE_BEYOND_HALT)
return -1;
percpu_entry = per_cpu_ptr(cpu_cstate_entry, cpu);
percpu_entry->states[cx->index].eax = 0;
percpu_entry->states[cx->index].ecx = 0;
/* Make sure we are running on right CPU */
retval = work_on_cpu(cpu, acpi_processor_ffh_cstate_probe_cpu, cx);
if (retval == 0) {
/* Use the hint in CST */
percpu_entry->states[cx->index].eax = cx->address;
percpu_entry->states[cx->index].ecx = MWAIT_ECX_INTERRUPT_BREAK;
}
return retval;
}
EXPORT_SYMBOL_GPL(acpi_processor_ffh_cstate_probe);