kernel_optimize_test/drivers/acpi/processor_perflib.c
Denis V. Lunev cf7acfab03 acpi: use non-racy method for proc entries creation
Use proc_create()/proc_create_data() to make sure that ->proc_fops and ->data
be setup before gluing PDE to main tree.

Add correct ->owner to proc_fops to fix reading/module unloading race.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:22 -07:00

787 lines
19 KiB
C

/*
* processor_perflib.c - ACPI Processor P-States Library ($Revision: 71 $)
*
* Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
* Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
* Copyright (C) 2004 Dominik Brodowski <linux@brodo.de>
* Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
* - Added processor hotplug support
*
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*
* This program is distributed in the hope that 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.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/cpufreq.h>
#ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/mutex.h>
#include <asm/uaccess.h>
#endif
#include <acpi/acpi_bus.h>
#include <acpi/processor.h>
#define ACPI_PROCESSOR_COMPONENT 0x01000000
#define ACPI_PROCESSOR_CLASS "processor"
#define ACPI_PROCESSOR_FILE_PERFORMANCE "performance"
#define _COMPONENT ACPI_PROCESSOR_COMPONENT
ACPI_MODULE_NAME("processor_perflib");
static DEFINE_MUTEX(performance_mutex);
/* Use cpufreq debug layer for _PPC changes. */
#define cpufreq_printk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_CORE, \
"cpufreq-core", msg)
/*
* _PPC support is implemented as a CPUfreq policy notifier:
* This means each time a CPUfreq driver registered also with
* the ACPI core is asked to change the speed policy, the maximum
* value is adjusted so that it is within the platform limit.
*
* Also, when a new platform limit value is detected, the CPUfreq
* policy is adjusted accordingly.
*/
static unsigned int ignore_ppc = 0;
module_param(ignore_ppc, uint, 0644);
MODULE_PARM_DESC(ignore_ppc, "If the frequency of your machine gets wrongly" \
"limited by BIOS, this should help");
#define PPC_REGISTERED 1
#define PPC_IN_USE 2
static int acpi_processor_ppc_status = 0;
static int acpi_processor_ppc_notifier(struct notifier_block *nb,
unsigned long event, void *data)
{
struct cpufreq_policy *policy = data;
struct acpi_processor *pr;
unsigned int ppc = 0;
if (ignore_ppc)
return 0;
mutex_lock(&performance_mutex);
if (event != CPUFREQ_INCOMPATIBLE)
goto out;
pr = processors[policy->cpu];
if (!pr || !pr->performance)
goto out;
ppc = (unsigned int)pr->performance_platform_limit;
if (ppc >= pr->performance->state_count)
goto out;
cpufreq_verify_within_limits(policy, 0,
pr->performance->states[ppc].
core_frequency * 1000);
out:
mutex_unlock(&performance_mutex);
return 0;
}
static struct notifier_block acpi_ppc_notifier_block = {
.notifier_call = acpi_processor_ppc_notifier,
};
static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
{
acpi_status status = 0;
unsigned long ppc = 0;
if (!pr)
return -EINVAL;
/*
* _PPC indicates the maximum state currently supported by the platform
* (e.g. 0 = states 0..n; 1 = states 1..n; etc.
*/
status = acpi_evaluate_integer(pr->handle, "_PPC", NULL, &ppc);
if (status != AE_NOT_FOUND)
acpi_processor_ppc_status |= PPC_IN_USE;
if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PPC"));
return -ENODEV;
}
cpufreq_printk("CPU %d: _PPC is %d - frequency %s limited\n", pr->id,
(int)ppc, ppc ? "" : "not");
pr->performance_platform_limit = (int)ppc;
return 0;
}
int acpi_processor_ppc_has_changed(struct acpi_processor *pr)
{
int ret;
if (ignore_ppc)
return 0;
ret = acpi_processor_get_platform_limit(pr);
if (ret < 0)
return (ret);
else
return cpufreq_update_policy(pr->id);
}
void acpi_processor_ppc_init(void)
{
if (!cpufreq_register_notifier
(&acpi_ppc_notifier_block, CPUFREQ_POLICY_NOTIFIER))
acpi_processor_ppc_status |= PPC_REGISTERED;
else
printk(KERN_DEBUG
"Warning: Processor Platform Limit not supported.\n");
}
void acpi_processor_ppc_exit(void)
{
if (acpi_processor_ppc_status & PPC_REGISTERED)
cpufreq_unregister_notifier(&acpi_ppc_notifier_block,
CPUFREQ_POLICY_NOTIFIER);
acpi_processor_ppc_status &= ~PPC_REGISTERED;
}
static int acpi_processor_get_performance_control(struct acpi_processor *pr)
{
int result = 0;
acpi_status status = 0;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *pct = NULL;
union acpi_object obj = { 0 };
status = acpi_evaluate_object(pr->handle, "_PCT", NULL, &buffer);
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PCT"));
return -ENODEV;
}
pct = (union acpi_object *)buffer.pointer;
if (!pct || (pct->type != ACPI_TYPE_PACKAGE)
|| (pct->package.count != 2)) {
printk(KERN_ERR PREFIX "Invalid _PCT data\n");
result = -EFAULT;
goto end;
}
/*
* control_register
*/
obj = pct->package.elements[0];
if ((obj.type != ACPI_TYPE_BUFFER)
|| (obj.buffer.length < sizeof(struct acpi_pct_register))
|| (obj.buffer.pointer == NULL)) {
printk(KERN_ERR PREFIX "Invalid _PCT data (control_register)\n");
result = -EFAULT;
goto end;
}
memcpy(&pr->performance->control_register, obj.buffer.pointer,
sizeof(struct acpi_pct_register));
/*
* status_register
*/
obj = pct->package.elements[1];
if ((obj.type != ACPI_TYPE_BUFFER)
|| (obj.buffer.length < sizeof(struct acpi_pct_register))
|| (obj.buffer.pointer == NULL)) {
printk(KERN_ERR PREFIX "Invalid _PCT data (status_register)\n");
result = -EFAULT;
goto end;
}
memcpy(&pr->performance->status_register, obj.buffer.pointer,
sizeof(struct acpi_pct_register));
end:
kfree(buffer.pointer);
return result;
}
static int acpi_processor_get_performance_states(struct acpi_processor *pr)
{
int result = 0;
acpi_status status = AE_OK;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
struct acpi_buffer format = { sizeof("NNNNNN"), "NNNNNN" };
struct acpi_buffer state = { 0, NULL };
union acpi_object *pss = NULL;
int i;
status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PSS"));
return -ENODEV;
}
pss = buffer.pointer;
if (!pss || (pss->type != ACPI_TYPE_PACKAGE)) {
printk(KERN_ERR PREFIX "Invalid _PSS data\n");
result = -EFAULT;
goto end;
}
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d performance states\n",
pss->package.count));
pr->performance->state_count = pss->package.count;
pr->performance->states =
kmalloc(sizeof(struct acpi_processor_px) * pss->package.count,
GFP_KERNEL);
if (!pr->performance->states) {
result = -ENOMEM;
goto end;
}
for (i = 0; i < pr->performance->state_count; i++) {
struct acpi_processor_px *px = &(pr->performance->states[i]);
state.length = sizeof(struct acpi_processor_px);
state.pointer = px;
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
status = acpi_extract_package(&(pss->package.elements[i]),
&format, &state);
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status, "Invalid _PSS data"));
result = -EFAULT;
kfree(pr->performance->states);
goto end;
}
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"State [%d]: core_frequency[%d] power[%d] transition_latency[%d] bus_master_latency[%d] control[0x%x] status[0x%x]\n",
i,
(u32) px->core_frequency,
(u32) px->power,
(u32) px->transition_latency,
(u32) px->bus_master_latency,
(u32) px->control, (u32) px->status));
if (!px->core_frequency) {
printk(KERN_ERR PREFIX
"Invalid _PSS data: freq is zero\n");
result = -EFAULT;
kfree(pr->performance->states);
goto end;
}
}
end:
kfree(buffer.pointer);
return result;
}
static int acpi_processor_get_performance_info(struct acpi_processor *pr)
{
int result = 0;
acpi_status status = AE_OK;
acpi_handle handle = NULL;
if (!pr || !pr->performance || !pr->handle)
return -EINVAL;
status = acpi_get_handle(pr->handle, "_PCT", &handle);
if (ACPI_FAILURE(status)) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"ACPI-based processor performance control unavailable\n"));
return -ENODEV;
}
result = acpi_processor_get_performance_control(pr);
if (result)
return result;
result = acpi_processor_get_performance_states(pr);
if (result)
return result;
return 0;
}
int acpi_processor_notify_smm(struct module *calling_module)
{
acpi_status status;
static int is_done = 0;
if (!(acpi_processor_ppc_status & PPC_REGISTERED))
return -EBUSY;
if (!try_module_get(calling_module))
return -EINVAL;
/* is_done is set to negative if an error occured,
* and to postitive if _no_ error occured, but SMM
* was already notified. This avoids double notification
* which might lead to unexpected results...
*/
if (is_done > 0) {
module_put(calling_module);
return 0;
} else if (is_done < 0) {
module_put(calling_module);
return is_done;
}
is_done = -EIO;
/* Can't write pstate_control to smi_command if either value is zero */
if ((!acpi_gbl_FADT.smi_command) || (!acpi_gbl_FADT.pstate_control)) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No SMI port or pstate_control\n"));
module_put(calling_module);
return 0;
}
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Writing pstate_control [0x%x] to smi_command [0x%x]\n",
acpi_gbl_FADT.pstate_control, acpi_gbl_FADT.smi_command));
status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
(u32) acpi_gbl_FADT.pstate_control, 8);
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status,
"Failed to write pstate_control [0x%x] to "
"smi_command [0x%x]", acpi_gbl_FADT.pstate_control,
acpi_gbl_FADT.smi_command));
module_put(calling_module);
return status;
}
/* Success. If there's no _PPC, we need to fear nothing, so
* we can allow the cpufreq driver to be rmmod'ed. */
is_done = 1;
if (!(acpi_processor_ppc_status & PPC_IN_USE))
module_put(calling_module);
return 0;
}
EXPORT_SYMBOL(acpi_processor_notify_smm);
#ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF
/* /proc/acpi/processor/../performance interface (DEPRECATED) */
static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file);
static struct file_operations acpi_processor_perf_fops = {
.owner = THIS_MODULE,
.open = acpi_processor_perf_open_fs,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int acpi_processor_perf_seq_show(struct seq_file *seq, void *offset)
{
struct acpi_processor *pr = seq->private;
int i;
if (!pr)
goto end;
if (!pr->performance) {
seq_puts(seq, "<not supported>\n");
goto end;
}
seq_printf(seq, "state count: %d\n"
"active state: P%d\n",
pr->performance->state_count, pr->performance->state);
seq_puts(seq, "states:\n");
for (i = 0; i < pr->performance->state_count; i++)
seq_printf(seq,
" %cP%d: %d MHz, %d mW, %d uS\n",
(i == pr->performance->state ? '*' : ' '), i,
(u32) pr->performance->states[i].core_frequency,
(u32) pr->performance->states[i].power,
(u32) pr->performance->states[i].transition_latency);
end:
return 0;
}
static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file)
{
return single_open(file, acpi_processor_perf_seq_show,
PDE(inode)->data);
}
static void acpi_cpufreq_add_file(struct acpi_processor *pr)
{
struct acpi_device *device = NULL;
if (acpi_bus_get_device(pr->handle, &device))
return;
/* add file 'performance' [R/W] */
proc_create_data(ACPI_PROCESSOR_FILE_PERFORMANCE, S_IFREG | S_IRUGO,
acpi_device_dir(device),
&acpi_processor_perf_fops, acpi_driver_data(device));
return;
}
static void acpi_cpufreq_remove_file(struct acpi_processor *pr)
{
struct acpi_device *device = NULL;
if (acpi_bus_get_device(pr->handle, &device))
return;
/* remove file 'performance' */
remove_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE,
acpi_device_dir(device));
return;
}
#else
static void acpi_cpufreq_add_file(struct acpi_processor *pr)
{
return;
}
static void acpi_cpufreq_remove_file(struct acpi_processor *pr)
{
return;
}
#endif /* CONFIG_X86_ACPI_CPUFREQ_PROC_INTF */
static int acpi_processor_get_psd(struct acpi_processor *pr)
{
int result = 0;
acpi_status status = AE_OK;
struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
struct acpi_buffer format = {sizeof("NNNNN"), "NNNNN"};
struct acpi_buffer state = {0, NULL};
union acpi_object *psd = NULL;
struct acpi_psd_package *pdomain;
status = acpi_evaluate_object(pr->handle, "_PSD", NULL, &buffer);
if (ACPI_FAILURE(status)) {
return -ENODEV;
}
psd = buffer.pointer;
if (!psd || (psd->type != ACPI_TYPE_PACKAGE)) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n"));
result = -EFAULT;
goto end;
}
if (psd->package.count != 1) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n"));
result = -EFAULT;
goto end;
}
pdomain = &(pr->performance->domain_info);
state.length = sizeof(struct acpi_psd_package);
state.pointer = pdomain;
status = acpi_extract_package(&(psd->package.elements[0]),
&format, &state);
if (ACPI_FAILURE(status)) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n"));
result = -EFAULT;
goto end;
}
if (pdomain->num_entries != ACPI_PSD_REV0_ENTRIES) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown _PSD:num_entries\n"));
result = -EFAULT;
goto end;
}
if (pdomain->revision != ACPI_PSD_REV0_REVISION) {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown _PSD:revision\n"));
result = -EFAULT;
goto end;
}
end:
kfree(buffer.pointer);
return result;
}
int acpi_processor_preregister_performance(
struct acpi_processor_performance *performance)
{
int count, count_target;
int retval = 0;
unsigned int i, j;
cpumask_t covered_cpus;
struct acpi_processor *pr;
struct acpi_psd_package *pdomain;
struct acpi_processor *match_pr;
struct acpi_psd_package *match_pdomain;
mutex_lock(&performance_mutex);
retval = 0;
/* Call _PSD for all CPUs */
for_each_possible_cpu(i) {
pr = processors[i];
if (!pr) {
/* Look only at processors in ACPI namespace */
continue;
}
if (pr->performance) {
retval = -EBUSY;
continue;
}
if (!performance || !percpu_ptr(performance, i)) {
retval = -EINVAL;
continue;
}
pr->performance = percpu_ptr(performance, i);
cpu_set(i, pr->performance->shared_cpu_map);
if (acpi_processor_get_psd(pr)) {
retval = -EINVAL;
continue;
}
}
if (retval)
goto err_ret;
/*
* Now that we have _PSD data from all CPUs, lets setup P-state
* domain info.
*/
for_each_possible_cpu(i) {
pr = processors[i];
if (!pr)
continue;
/* Basic validity check for domain info */
pdomain = &(pr->performance->domain_info);
if ((pdomain->revision != ACPI_PSD_REV0_REVISION) ||
(pdomain->num_entries != ACPI_PSD_REV0_ENTRIES)) {
retval = -EINVAL;
goto err_ret;
}
if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
retval = -EINVAL;
goto err_ret;
}
}
cpus_clear(covered_cpus);
for_each_possible_cpu(i) {
pr = processors[i];
if (!pr)
continue;
if (cpu_isset(i, covered_cpus))
continue;
pdomain = &(pr->performance->domain_info);
cpu_set(i, pr->performance->shared_cpu_map);
cpu_set(i, covered_cpus);
if (pdomain->num_processors <= 1)
continue;
/* Validate the Domain info */
count_target = pdomain->num_processors;
count = 1;
if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL)
pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL;
else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL)
pr->performance->shared_type = CPUFREQ_SHARED_TYPE_HW;
else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY)
pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ANY;
for_each_possible_cpu(j) {
if (i == j)
continue;
match_pr = processors[j];
if (!match_pr)
continue;
match_pdomain = &(match_pr->performance->domain_info);
if (match_pdomain->domain != pdomain->domain)
continue;
/* Here i and j are in the same domain */
if (match_pdomain->num_processors != count_target) {
retval = -EINVAL;
goto err_ret;
}
if (pdomain->coord_type != match_pdomain->coord_type) {
retval = -EINVAL;
goto err_ret;
}
cpu_set(j, covered_cpus);
cpu_set(j, pr->performance->shared_cpu_map);
count++;
}
for_each_possible_cpu(j) {
if (i == j)
continue;
match_pr = processors[j];
if (!match_pr)
continue;
match_pdomain = &(match_pr->performance->domain_info);
if (match_pdomain->domain != pdomain->domain)
continue;
match_pr->performance->shared_type =
pr->performance->shared_type;
match_pr->performance->shared_cpu_map =
pr->performance->shared_cpu_map;
}
}
err_ret:
for_each_possible_cpu(i) {
pr = processors[i];
if (!pr || !pr->performance)
continue;
/* Assume no coordination on any error parsing domain info */
if (retval) {
cpus_clear(pr->performance->shared_cpu_map);
cpu_set(i, pr->performance->shared_cpu_map);
pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL;
}
pr->performance = NULL; /* Will be set for real in register */
}
mutex_unlock(&performance_mutex);
return retval;
}
EXPORT_SYMBOL(acpi_processor_preregister_performance);
int
acpi_processor_register_performance(struct acpi_processor_performance
*performance, unsigned int cpu)
{
struct acpi_processor *pr;
if (!(acpi_processor_ppc_status & PPC_REGISTERED))
return -EINVAL;
mutex_lock(&performance_mutex);
pr = processors[cpu];
if (!pr) {
mutex_unlock(&performance_mutex);
return -ENODEV;
}
if (pr->performance) {
mutex_unlock(&performance_mutex);
return -EBUSY;
}
WARN_ON(!performance);
pr->performance = performance;
if (acpi_processor_get_performance_info(pr)) {
pr->performance = NULL;
mutex_unlock(&performance_mutex);
return -EIO;
}
acpi_cpufreq_add_file(pr);
mutex_unlock(&performance_mutex);
return 0;
}
EXPORT_SYMBOL(acpi_processor_register_performance);
void
acpi_processor_unregister_performance(struct acpi_processor_performance
*performance, unsigned int cpu)
{
struct acpi_processor *pr;
mutex_lock(&performance_mutex);
pr = processors[cpu];
if (!pr) {
mutex_unlock(&performance_mutex);
return;
}
if (pr->performance)
kfree(pr->performance->states);
pr->performance = NULL;
acpi_cpufreq_remove_file(pr);
mutex_unlock(&performance_mutex);
return;
}
EXPORT_SYMBOL(acpi_processor_unregister_performance);