linux/drivers/acpi/acpi_pad.c
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00

519 lines
13 KiB
C

/*
* acpi_pad.c ACPI Processor Aggregator Driver
*
* Copyright (c) 2009, Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*
*/
#include <linux/kernel.h>
#include <linux/cpumask.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/kthread.h>
#include <linux/freezer.h>
#include <linux/cpu.h>
#include <linux/clockchips.h>
#include <linux/slab.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>
#define ACPI_PROCESSOR_AGGREGATOR_CLASS "processor_aggregator"
#define ACPI_PROCESSOR_AGGREGATOR_DEVICE_NAME "Processor Aggregator"
#define ACPI_PROCESSOR_AGGREGATOR_NOTIFY 0x80
static DEFINE_MUTEX(isolated_cpus_lock);
#define MWAIT_SUBSTATE_MASK (0xf)
#define MWAIT_CSTATE_MASK (0xf)
#define MWAIT_SUBSTATE_SIZE (4)
#define CPUID_MWAIT_LEAF (5)
#define CPUID5_ECX_EXTENSIONS_SUPPORTED (0x1)
#define CPUID5_ECX_INTERRUPT_BREAK (0x2)
static unsigned long power_saving_mwait_eax;
static void power_saving_mwait_init(void)
{
unsigned int eax, ebx, ecx, edx;
unsigned int highest_cstate = 0;
unsigned int highest_subcstate = 0;
int i;
if (!boot_cpu_has(X86_FEATURE_MWAIT))
return;
if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF)
return;
cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &edx);
if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED) ||
!(ecx & CPUID5_ECX_INTERRUPT_BREAK))
return;
edx >>= MWAIT_SUBSTATE_SIZE;
for (i = 0; i < 7 && edx; i++, edx >>= MWAIT_SUBSTATE_SIZE) {
if (edx & MWAIT_SUBSTATE_MASK) {
highest_cstate = i;
highest_subcstate = edx & MWAIT_SUBSTATE_MASK;
}
}
power_saving_mwait_eax = (highest_cstate << MWAIT_SUBSTATE_SIZE) |
(highest_subcstate - 1);
for_each_online_cpu(i)
clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ON, &i);
#if defined(CONFIG_GENERIC_TIME) && defined(CONFIG_X86)
switch (boot_cpu_data.x86_vendor) {
case X86_VENDOR_AMD:
case X86_VENDOR_INTEL:
/*
* AMD Fam10h TSC will tick in all
* C/P/S0/S1 states when this bit is set.
*/
if (boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
return;
/*FALL THROUGH*/
default:
/* TSC could halt in idle, so notify users */
mark_tsc_unstable("TSC halts in idle");
}
#endif
}
static unsigned long cpu_weight[NR_CPUS];
static int tsk_in_cpu[NR_CPUS] = {[0 ... NR_CPUS-1] = -1};
static DECLARE_BITMAP(pad_busy_cpus_bits, NR_CPUS);
static void round_robin_cpu(unsigned int tsk_index)
{
struct cpumask *pad_busy_cpus = to_cpumask(pad_busy_cpus_bits);
cpumask_var_t tmp;
int cpu;
unsigned long min_weight = -1;
unsigned long uninitialized_var(preferred_cpu);
if (!alloc_cpumask_var(&tmp, GFP_KERNEL))
return;
mutex_lock(&isolated_cpus_lock);
cpumask_clear(tmp);
for_each_cpu(cpu, pad_busy_cpus)
cpumask_or(tmp, tmp, topology_thread_cpumask(cpu));
cpumask_andnot(tmp, cpu_online_mask, tmp);
/* avoid HT sibilings if possible */
if (cpumask_empty(tmp))
cpumask_andnot(tmp, cpu_online_mask, pad_busy_cpus);
if (cpumask_empty(tmp)) {
mutex_unlock(&isolated_cpus_lock);
return;
}
for_each_cpu(cpu, tmp) {
if (cpu_weight[cpu] < min_weight) {
min_weight = cpu_weight[cpu];
preferred_cpu = cpu;
}
}
if (tsk_in_cpu[tsk_index] != -1)
cpumask_clear_cpu(tsk_in_cpu[tsk_index], pad_busy_cpus);
tsk_in_cpu[tsk_index] = preferred_cpu;
cpumask_set_cpu(preferred_cpu, pad_busy_cpus);
cpu_weight[preferred_cpu]++;
mutex_unlock(&isolated_cpus_lock);
set_cpus_allowed_ptr(current, cpumask_of(preferred_cpu));
}
static void exit_round_robin(unsigned int tsk_index)
{
struct cpumask *pad_busy_cpus = to_cpumask(pad_busy_cpus_bits);
cpumask_clear_cpu(tsk_in_cpu[tsk_index], pad_busy_cpus);
tsk_in_cpu[tsk_index] = -1;
}
static unsigned int idle_pct = 5; /* percentage */
static unsigned int round_robin_time = 10; /* second */
static int power_saving_thread(void *data)
{
struct sched_param param = {.sched_priority = 1};
int do_sleep;
unsigned int tsk_index = (unsigned long)data;
u64 last_jiffies = 0;
sched_setscheduler(current, SCHED_RR, &param);
while (!kthread_should_stop()) {
int cpu;
u64 expire_time;
try_to_freeze();
/* round robin to cpus */
if (last_jiffies + round_robin_time * HZ < jiffies) {
last_jiffies = jiffies;
round_robin_cpu(tsk_index);
}
do_sleep = 0;
current_thread_info()->status &= ~TS_POLLING;
/*
* TS_POLLING-cleared state must be visible before we test
* NEED_RESCHED:
*/
smp_mb();
expire_time = jiffies + HZ * (100 - idle_pct) / 100;
while (!need_resched()) {
local_irq_disable();
cpu = smp_processor_id();
clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER,
&cpu);
stop_critical_timings();
__monitor((void *)&current_thread_info()->flags, 0, 0);
smp_mb();
if (!need_resched())
__mwait(power_saving_mwait_eax, 1);
start_critical_timings();
clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT,
&cpu);
local_irq_enable();
if (jiffies > expire_time) {
do_sleep = 1;
break;
}
}
current_thread_info()->status |= TS_POLLING;
/*
* current sched_rt has threshold for rt task running time.
* When a rt task uses 95% CPU time, the rt thread will be
* scheduled out for 5% CPU time to not starve other tasks. But
* the mechanism only works when all CPUs have RT task running,
* as if one CPU hasn't RT task, RT task from other CPUs will
* borrow CPU time from this CPU and cause RT task use > 95%
* CPU time. To make 'avoid starvation' work, takes a nap here.
*/
if (do_sleep)
schedule_timeout_killable(HZ * idle_pct / 100);
}
exit_round_robin(tsk_index);
return 0;
}
static struct task_struct *ps_tsks[NR_CPUS];
static unsigned int ps_tsk_num;
static int create_power_saving_task(void)
{
int rc = -ENOMEM;
ps_tsks[ps_tsk_num] = kthread_run(power_saving_thread,
(void *)(unsigned long)ps_tsk_num,
"power_saving/%d", ps_tsk_num);
rc = IS_ERR(ps_tsks[ps_tsk_num]) ? PTR_ERR(ps_tsks[ps_tsk_num]) : 0;
if (!rc)
ps_tsk_num++;
else
ps_tsks[ps_tsk_num] = NULL;
return rc;
}
static void destroy_power_saving_task(void)
{
if (ps_tsk_num > 0) {
ps_tsk_num--;
kthread_stop(ps_tsks[ps_tsk_num]);
ps_tsks[ps_tsk_num] = NULL;
}
}
static void set_power_saving_task_num(unsigned int num)
{
if (num > ps_tsk_num) {
while (ps_tsk_num < num) {
if (create_power_saving_task())
return;
}
} else if (num < ps_tsk_num) {
while (ps_tsk_num > num)
destroy_power_saving_task();
}
}
static void acpi_pad_idle_cpus(unsigned int num_cpus)
{
get_online_cpus();
num_cpus = min_t(unsigned int, num_cpus, num_online_cpus());
set_power_saving_task_num(num_cpus);
put_online_cpus();
}
static uint32_t acpi_pad_idle_cpus_num(void)
{
return ps_tsk_num;
}
static ssize_t acpi_pad_rrtime_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
unsigned long num;
if (strict_strtoul(buf, 0, &num))
return -EINVAL;
if (num < 1 || num >= 100)
return -EINVAL;
mutex_lock(&isolated_cpus_lock);
round_robin_time = num;
mutex_unlock(&isolated_cpus_lock);
return count;
}
static ssize_t acpi_pad_rrtime_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return scnprintf(buf, PAGE_SIZE, "%d", round_robin_time);
}
static DEVICE_ATTR(rrtime, S_IRUGO|S_IWUSR,
acpi_pad_rrtime_show,
acpi_pad_rrtime_store);
static ssize_t acpi_pad_idlepct_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
unsigned long num;
if (strict_strtoul(buf, 0, &num))
return -EINVAL;
if (num < 1 || num >= 100)
return -EINVAL;
mutex_lock(&isolated_cpus_lock);
idle_pct = num;
mutex_unlock(&isolated_cpus_lock);
return count;
}
static ssize_t acpi_pad_idlepct_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return scnprintf(buf, PAGE_SIZE, "%d", idle_pct);
}
static DEVICE_ATTR(idlepct, S_IRUGO|S_IWUSR,
acpi_pad_idlepct_show,
acpi_pad_idlepct_store);
static ssize_t acpi_pad_idlecpus_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
unsigned long num;
if (strict_strtoul(buf, 0, &num))
return -EINVAL;
mutex_lock(&isolated_cpus_lock);
acpi_pad_idle_cpus(num);
mutex_unlock(&isolated_cpus_lock);
return count;
}
static ssize_t acpi_pad_idlecpus_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return cpumask_scnprintf(buf, PAGE_SIZE,
to_cpumask(pad_busy_cpus_bits));
}
static DEVICE_ATTR(idlecpus, S_IRUGO|S_IWUSR,
acpi_pad_idlecpus_show,
acpi_pad_idlecpus_store);
static int acpi_pad_add_sysfs(struct acpi_device *device)
{
int result;
result = device_create_file(&device->dev, &dev_attr_idlecpus);
if (result)
return -ENODEV;
result = device_create_file(&device->dev, &dev_attr_idlepct);
if (result) {
device_remove_file(&device->dev, &dev_attr_idlecpus);
return -ENODEV;
}
result = device_create_file(&device->dev, &dev_attr_rrtime);
if (result) {
device_remove_file(&device->dev, &dev_attr_idlecpus);
device_remove_file(&device->dev, &dev_attr_idlepct);
return -ENODEV;
}
return 0;
}
static void acpi_pad_remove_sysfs(struct acpi_device *device)
{
device_remove_file(&device->dev, &dev_attr_idlecpus);
device_remove_file(&device->dev, &dev_attr_idlepct);
device_remove_file(&device->dev, &dev_attr_rrtime);
}
/* Query firmware how many CPUs should be idle */
static int acpi_pad_pur(acpi_handle handle, int *num_cpus)
{
struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
union acpi_object *package;
int rev, num, ret = -EINVAL;
if (ACPI_FAILURE(acpi_evaluate_object(handle, "_PUR", NULL, &buffer)))
return -EINVAL;
if (!buffer.length || !buffer.pointer)
return -EINVAL;
package = buffer.pointer;
if (package->type != ACPI_TYPE_PACKAGE || package->package.count != 2)
goto out;
rev = package->package.elements[0].integer.value;
num = package->package.elements[1].integer.value;
if (rev != 1 || num < 0)
goto out;
*num_cpus = num;
ret = 0;
out:
kfree(buffer.pointer);
return ret;
}
/* Notify firmware how many CPUs are idle */
static void acpi_pad_ost(acpi_handle handle, int stat,
uint32_t idle_cpus)
{
union acpi_object params[3] = {
{.type = ACPI_TYPE_INTEGER,},
{.type = ACPI_TYPE_INTEGER,},
{.type = ACPI_TYPE_BUFFER,},
};
struct acpi_object_list arg_list = {3, params};
params[0].integer.value = ACPI_PROCESSOR_AGGREGATOR_NOTIFY;
params[1].integer.value = stat;
params[2].buffer.length = 4;
params[2].buffer.pointer = (void *)&idle_cpus;
acpi_evaluate_object(handle, "_OST", &arg_list, NULL);
}
static void acpi_pad_handle_notify(acpi_handle handle)
{
int num_cpus;
uint32_t idle_cpus;
mutex_lock(&isolated_cpus_lock);
if (acpi_pad_pur(handle, &num_cpus)) {
mutex_unlock(&isolated_cpus_lock);
return;
}
acpi_pad_idle_cpus(num_cpus);
idle_cpus = acpi_pad_idle_cpus_num();
acpi_pad_ost(handle, 0, idle_cpus);
mutex_unlock(&isolated_cpus_lock);
}
static void acpi_pad_notify(acpi_handle handle, u32 event,
void *data)
{
struct acpi_device *device = data;
switch (event) {
case ACPI_PROCESSOR_AGGREGATOR_NOTIFY:
acpi_pad_handle_notify(handle);
acpi_bus_generate_proc_event(device, event, 0);
acpi_bus_generate_netlink_event(device->pnp.device_class,
dev_name(&device->dev), event, 0);
break;
default:
printk(KERN_WARNING"Unsupported event [0x%x]\n", event);
break;
}
}
static int acpi_pad_add(struct acpi_device *device)
{
acpi_status status;
strcpy(acpi_device_name(device), ACPI_PROCESSOR_AGGREGATOR_DEVICE_NAME);
strcpy(acpi_device_class(device), ACPI_PROCESSOR_AGGREGATOR_CLASS);
if (acpi_pad_add_sysfs(device))
return -ENODEV;
status = acpi_install_notify_handler(device->handle,
ACPI_DEVICE_NOTIFY, acpi_pad_notify, device);
if (ACPI_FAILURE(status)) {
acpi_pad_remove_sysfs(device);
return -ENODEV;
}
return 0;
}
static int acpi_pad_remove(struct acpi_device *device,
int type)
{
mutex_lock(&isolated_cpus_lock);
acpi_pad_idle_cpus(0);
mutex_unlock(&isolated_cpus_lock);
acpi_remove_notify_handler(device->handle,
ACPI_DEVICE_NOTIFY, acpi_pad_notify);
acpi_pad_remove_sysfs(device);
return 0;
}
static const struct acpi_device_id pad_device_ids[] = {
{"ACPI000C", 0},
{"", 0},
};
MODULE_DEVICE_TABLE(acpi, pad_device_ids);
static struct acpi_driver acpi_pad_driver = {
.name = "processor_aggregator",
.class = ACPI_PROCESSOR_AGGREGATOR_CLASS,
.ids = pad_device_ids,
.ops = {
.add = acpi_pad_add,
.remove = acpi_pad_remove,
},
};
static int __init acpi_pad_init(void)
{
power_saving_mwait_init();
if (power_saving_mwait_eax == 0)
return -EINVAL;
return acpi_bus_register_driver(&acpi_pad_driver);
}
static void __exit acpi_pad_exit(void)
{
acpi_bus_unregister_driver(&acpi_pad_driver);
}
module_init(acpi_pad_init);
module_exit(acpi_pad_exit);
MODULE_AUTHOR("Shaohua Li<shaohua.li@intel.com>");
MODULE_DESCRIPTION("ACPI Processor Aggregator Driver");
MODULE_LICENSE("GPL");