9133664097
The kernel used to contain two functions for length-delimited, case-insensitive string comparison, strnicmp with correct semantics and a slightly buggy strncasecmp. The latter is the POSIX name, so strnicmp was renamed to strncasecmp, and strnicmp made into a wrapper for the new strncasecmp to avoid breaking existing users. To allow the compat wrapper strnicmp to be removed at some point in the future, and to avoid the extra indirection cost, do s/strnicmp/strncasecmp/g. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
99 lines
2.2 KiB
C
99 lines
2.2 KiB
C
/*
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* governor.c - governor support
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*
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* (C) 2006-2007 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
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* Shaohua Li <shaohua.li@intel.com>
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* Adam Belay <abelay@novell.com>
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*
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* This code is licenced under the GPL.
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*/
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#include <linux/mutex.h>
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#include <linux/module.h>
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#include <linux/cpuidle.h>
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#include "cpuidle.h"
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LIST_HEAD(cpuidle_governors);
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struct cpuidle_governor *cpuidle_curr_governor;
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/**
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* __cpuidle_find_governor - finds a governor of the specified name
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* @str: the name
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*
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* Must be called with cpuidle_lock acquired.
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*/
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static struct cpuidle_governor * __cpuidle_find_governor(const char *str)
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{
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struct cpuidle_governor *gov;
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list_for_each_entry(gov, &cpuidle_governors, governor_list)
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if (!strncasecmp(str, gov->name, CPUIDLE_NAME_LEN))
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return gov;
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return NULL;
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}
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/**
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* cpuidle_switch_governor - changes the governor
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* @gov: the new target governor
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*
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* NOTE: "gov" can be NULL to specify disabled
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* Must be called with cpuidle_lock acquired.
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*/
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int cpuidle_switch_governor(struct cpuidle_governor *gov)
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{
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struct cpuidle_device *dev;
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if (gov == cpuidle_curr_governor)
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return 0;
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cpuidle_uninstall_idle_handler();
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if (cpuidle_curr_governor) {
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list_for_each_entry(dev, &cpuidle_detected_devices, device_list)
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cpuidle_disable_device(dev);
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module_put(cpuidle_curr_governor->owner);
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}
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cpuidle_curr_governor = gov;
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if (gov) {
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if (!try_module_get(cpuidle_curr_governor->owner))
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return -EINVAL;
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list_for_each_entry(dev, &cpuidle_detected_devices, device_list)
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cpuidle_enable_device(dev);
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cpuidle_install_idle_handler();
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printk(KERN_INFO "cpuidle: using governor %s\n", gov->name);
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}
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return 0;
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}
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/**
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* cpuidle_register_governor - registers a governor
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* @gov: the governor
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*/
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int cpuidle_register_governor(struct cpuidle_governor *gov)
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{
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int ret = -EEXIST;
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if (!gov || !gov->select)
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return -EINVAL;
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if (cpuidle_disabled())
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return -ENODEV;
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mutex_lock(&cpuidle_lock);
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if (__cpuidle_find_governor(gov->name) == NULL) {
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ret = 0;
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list_add_tail(&gov->governor_list, &cpuidle_governors);
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if (!cpuidle_curr_governor ||
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cpuidle_curr_governor->rating < gov->rating)
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cpuidle_switch_governor(gov);
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}
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mutex_unlock(&cpuidle_lock);
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return ret;
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}
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