Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq
authorLinus Torvalds <torvalds@g5.osdl.org>
Tue, 4 Jul 2006 21:00:26 +0000 (14:00 -0700)
committerLinus Torvalds <torvalds@g5.osdl.org>
Tue, 4 Jul 2006 21:00:26 +0000 (14:00 -0700)
* master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq:
  Move workqueue exports to where the functions are defined.
  [CPUFREQ] Misc cleanups in ondemand.
  [CPUFREQ] Make ondemand sampling per CPU and remove the mutex usage in sampling path.
  [CPUFREQ] Add queue_delayed_work_on() interface for workqueues.
  [CPUFREQ] Remove slowdown from ondemand sampling path.

drivers/cpufreq/cpufreq_ondemand.c
include/asm-generic/cputime.h
include/linux/workqueue.h
kernel/workqueue.c

index 693e540..8729992 100644 (file)
 
 #include <linux/kernel.h>
 #include <linux/module.h>
-#include <linux/smp.h>
 #include <linux/init.h>
-#include <linux/interrupt.h>
-#include <linux/ctype.h>
 #include <linux/cpufreq.h>
-#include <linux/sysctl.h>
-#include <linux/types.h>
-#include <linux/fs.h>
-#include <linux/sysfs.h>
 #include <linux/cpu.h>
-#include <linux/sched.h>
-#include <linux/kmod.h>
-#include <linux/workqueue.h>
 #include <linux/jiffies.h>
 #include <linux/kernel_stat.h>
-#include <linux/percpu.h>
 #include <linux/mutex.h>
 
 /*
@@ -56,16 +45,15 @@ static unsigned int def_sampling_rate;
 #define MIN_SAMPLING_RATE                      (def_sampling_rate / MIN_SAMPLING_RATE_RATIO)
 #define MAX_SAMPLING_RATE                      (500 * def_sampling_rate)
 #define DEF_SAMPLING_RATE_LATENCY_MULTIPLIER   (1000)
-#define DEF_SAMPLING_DOWN_FACTOR               (1)
-#define MAX_SAMPLING_DOWN_FACTOR               (10)
 #define TRANSITION_LATENCY_LIMIT               (10 * 1000)
 
 static void do_dbs_timer(void *data);
 
 struct cpu_dbs_info_s {
+       cputime64_t prev_cpu_idle;
+       cputime64_t prev_cpu_wall;
        struct cpufreq_policy *cur_policy;
-       unsigned int prev_cpu_idle_up;
-       unsigned int prev_cpu_idle_down;
+       struct work_struct work;
        unsigned int enable;
 };
 static DEFINE_PER_CPU(struct cpu_dbs_info_s, cpu_dbs_info);
@@ -80,31 +68,32 @@ static unsigned int dbs_enable;     /* number of CPUs using this policy */
  * cpu_hotplug lock should be taken before that. Note that cpu_hotplug lock
  * is recursive for the same process. -Venki
  */
-static DEFINE_MUTEX (dbs_mutex);
-static DECLARE_WORK    (dbs_work, do_dbs_timer, NULL);
+static DEFINE_MUTEX(dbs_mutex);
 
-static struct workqueue_struct *dbs_workq;
+static struct workqueue_struct *kondemand_wq;
 
 struct dbs_tuners {
        unsigned int sampling_rate;
-       unsigned int sampling_down_factor;
        unsigned int up_threshold;
        unsigned int ignore_nice;
 };
 
 static struct dbs_tuners dbs_tuners_ins = {
        .up_threshold = DEF_FREQUENCY_UP_THRESHOLD,
-       .sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR,
        .ignore_nice = 0,
 };
 
-static inline unsigned int get_cpu_idle_time(unsigned int cpu)
+static inline cputime64_t get_cpu_idle_time(unsigned int cpu)
 {
-       return  kstat_cpu(cpu).cpustat.idle +
-               kstat_cpu(cpu).cpustat.iowait +
-               ( dbs_tuners_ins.ignore_nice ?
-                 kstat_cpu(cpu).cpustat.nice :
-                 0);
+       cputime64_t retval;
+
+       retval = cputime64_add(kstat_cpu(cpu).cpustat.idle,
+                       kstat_cpu(cpu).cpustat.iowait);
+
+       if (dbs_tuners_ins.ignore_nice)
+               retval = cputime64_add(retval, kstat_cpu(cpu).cpustat.nice);
+
+       return retval;
 }
 
 /************************** sysfs interface ************************/
@@ -133,35 +122,15 @@ static ssize_t show_##file_name                                           \
        return sprintf(buf, "%u\n", dbs_tuners_ins.object);             \
 }
 show_one(sampling_rate, sampling_rate);
-show_one(sampling_down_factor, sampling_down_factor);
 show_one(up_threshold, up_threshold);
 show_one(ignore_nice_load, ignore_nice);
 
-static ssize_t store_sampling_down_factor(struct cpufreq_policy *unused,
-               const char *buf, size_t count)
-{
-       unsigned int input;
-       int ret;
-       ret = sscanf (buf, "%u", &input);
-       if (ret != 1 )
-               return -EINVAL;
-
-       if (input > MAX_SAMPLING_DOWN_FACTOR || input < 1)
-               return -EINVAL;
-
-       mutex_lock(&dbs_mutex);
-       dbs_tuners_ins.sampling_down_factor = input;
-       mutex_unlock(&dbs_mutex);
-
-       return count;
-}
-
 static ssize_t store_sampling_rate(struct cpufreq_policy *unused,
                const char *buf, size_t count)
 {
        unsigned int input;
        int ret;
-       ret = sscanf (buf, "%u", &input);
+       ret = sscanf(buf, "%u", &input);
 
        mutex_lock(&dbs_mutex);
        if (ret != 1 || input > MAX_SAMPLING_RATE || input < MIN_SAMPLING_RATE) {
@@ -180,7 +149,7 @@ static ssize_t store_up_threshold(struct cpufreq_policy *unused,
 {
        unsigned int input;
        int ret;
-       ret = sscanf (buf, "%u", &input);
+       ret = sscanf(buf, "%u", &input);
 
        mutex_lock(&dbs_mutex);
        if (ret != 1 || input > MAX_FREQUENCY_UP_THRESHOLD ||
@@ -203,7 +172,7 @@ static ssize_t store_ignore_nice_load(struct cpufreq_policy *policy,
 
        unsigned int j;
 
-       ret = sscanf (buf, "%u", &input);
+       ret = sscanf(buf, "%u", &input);
        if ( ret != 1 )
                return -EINVAL;
 
@@ -217,12 +186,12 @@ static ssize_t store_ignore_nice_load(struct cpufreq_policy *policy,
        }
        dbs_tuners_ins.ignore_nice = input;
 
-       /* we need to re-evaluate prev_cpu_idle_up and prev_cpu_idle_down */
+       /* we need to re-evaluate prev_cpu_idle */
        for_each_online_cpu(j) {
-               struct cpu_dbs_info_s *j_dbs_info;
-               j_dbs_info = &per_cpu(cpu_dbs_info, j);
-               j_dbs_info->prev_cpu_idle_up = get_cpu_idle_time(j);
-               j_dbs_info->prev_cpu_idle_down = j_dbs_info->prev_cpu_idle_up;
+               struct cpu_dbs_info_s *dbs_info;
+               dbs_info = &per_cpu(cpu_dbs_info, j);
+               dbs_info->prev_cpu_idle = get_cpu_idle_time(j);
+               dbs_info->prev_cpu_wall = get_jiffies_64();
        }
        mutex_unlock(&dbs_mutex);
 
@@ -234,7 +203,6 @@ static struct freq_attr _name = \
 __ATTR(_name, 0644, show_##_name, store_##_name)
 
 define_one_rw(sampling_rate);
-define_one_rw(sampling_down_factor);
 define_one_rw(up_threshold);
 define_one_rw(ignore_nice_load);
 
@@ -242,7 +210,6 @@ static struct attribute * dbs_attributes[] = {
        &sampling_rate_max.attr,
        &sampling_rate_min.attr,
        &sampling_rate.attr,
-       &sampling_down_factor.attr,
        &up_threshold.attr,
        &ignore_nice_load.attr,
        NULL
@@ -255,26 +222,27 @@ static struct attribute_group dbs_attr_group = {
 
 /************************** sysfs end ************************/
 
-static void dbs_check_cpu(int cpu)
+static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
 {
-       unsigned int idle_ticks, up_idle_ticks, total_ticks;
-       unsigned int freq_next;
-       unsigned int freq_down_sampling_rate;
-       static int down_skip[NR_CPUS];
-       struct cpu_dbs_info_s *this_dbs_info;
+       unsigned int idle_ticks, total_ticks;
+       unsigned int load;
+       cputime64_t cur_jiffies;
 
        struct cpufreq_policy *policy;
        unsigned int j;
 
-       this_dbs_info = &per_cpu(cpu_dbs_info, cpu);
        if (!this_dbs_info->enable)
                return;
 
        policy = this_dbs_info->cur_policy;
+       cur_jiffies = jiffies64_to_cputime64(get_jiffies_64());
+       total_ticks = (unsigned int) cputime64_sub(cur_jiffies,
+                       this_dbs_info->prev_cpu_wall);
+       this_dbs_info->prev_cpu_wall = cur_jiffies;
        /*
         * Every sampling_rate, we check, if current idle time is less
         * than 20% (default), then we try to increase frequency
-        * Every sampling_rate*sampling_down_factor, we look for a the lowest
+        * Every sampling_rate, we look for a the lowest
         * frequency which can sustain the load while keeping idle time over
         * 30%. If such a frequency exist, we try to decrease to this frequency.
         *
@@ -283,36 +251,26 @@ static void dbs_check_cpu(int cpu)
         * 5% (default) of current frequency
         */
 
-       /* Check for frequency increase */
+       /* Get Idle Time */
        idle_ticks = UINT_MAX;
        for_each_cpu_mask(j, policy->cpus) {
-               unsigned int tmp_idle_ticks, total_idle_ticks;
+               cputime64_t total_idle_ticks;
+               unsigned int tmp_idle_ticks;
                struct cpu_dbs_info_s *j_dbs_info;
 
                j_dbs_info = &per_cpu(cpu_dbs_info, j);
                total_idle_ticks = get_cpu_idle_time(j);
-               tmp_idle_ticks = total_idle_ticks -
-                       j_dbs_info->prev_cpu_idle_up;
-               j_dbs_info->prev_cpu_idle_up = total_idle_ticks;
+               tmp_idle_ticks = (unsigned int) cputime64_sub(total_idle_ticks,
+                               j_dbs_info->prev_cpu_idle);
+               j_dbs_info->prev_cpu_idle = total_idle_ticks;
 
                if (tmp_idle_ticks < idle_ticks)
                        idle_ticks = tmp_idle_ticks;
        }
+       load = (100 * (total_ticks - idle_ticks)) / total_ticks;
 
-       /* Scale idle ticks by 100 and compare with up and down ticks */
-       idle_ticks *= 100;
-       up_idle_ticks = (100 - dbs_tuners_ins.up_threshold) *
-                       usecs_to_jiffies(dbs_tuners_ins.sampling_rate);
-
-       if (idle_ticks < up_idle_ticks) {
-               down_skip[cpu] = 0;
-               for_each_cpu_mask(j, policy->cpus) {
-                       struct cpu_dbs_info_s *j_dbs_info;
-
-                       j_dbs_info = &per_cpu(cpu_dbs_info, j);
-                       j_dbs_info->prev_cpu_idle_down =
-                                       j_dbs_info->prev_cpu_idle_up;
-               }
+       /* Check for frequency increase */
+       if (load > dbs_tuners_ins.up_threshold) {
                /* if we are already at full speed then break out early */
                if (policy->cur == policy->max)
                        return;
@@ -323,83 +281,49 @@ static void dbs_check_cpu(int cpu)
        }
 
        /* Check for frequency decrease */
-       down_skip[cpu]++;
-       if (down_skip[cpu] < dbs_tuners_ins.sampling_down_factor)
-               return;
-
-       idle_ticks = UINT_MAX;
-       for_each_cpu_mask(j, policy->cpus) {
-               unsigned int tmp_idle_ticks, total_idle_ticks;
-               struct cpu_dbs_info_s *j_dbs_info;
-
-               j_dbs_info = &per_cpu(cpu_dbs_info, j);
-               /* Check for frequency decrease */
-               total_idle_ticks = j_dbs_info->prev_cpu_idle_up;
-               tmp_idle_ticks = total_idle_ticks -
-                       j_dbs_info->prev_cpu_idle_down;
-               j_dbs_info->prev_cpu_idle_down = total_idle_ticks;
-
-               if (tmp_idle_ticks < idle_ticks)
-                       idle_ticks = tmp_idle_ticks;
-       }
-
-       down_skip[cpu] = 0;
        /* if we cannot reduce the frequency anymore, break out early */
        if (policy->cur == policy->min)
                return;
 
-       /* Compute how many ticks there are between two measurements */
-       freq_down_sampling_rate = dbs_tuners_ins.sampling_rate *
-               dbs_tuners_ins.sampling_down_factor;
-       total_ticks = usecs_to_jiffies(freq_down_sampling_rate);
-
        /*
         * The optimal frequency is the frequency that is the lowest that
         * can support the current CPU usage without triggering the up
         * policy. To be safe, we focus 10 points under the threshold.
         */
-       freq_next = ((total_ticks - idle_ticks) * 100) / total_ticks;
-       freq_next = (freq_next * policy->cur) /
+       if (load < (dbs_tuners_ins.up_threshold - 10)) {
+               unsigned int freq_next;
+               freq_next = (policy->cur * load) /
                        (dbs_tuners_ins.up_threshold - 10);
 
-       if (freq_next < policy->min)
-               freq_next = policy->min;
-
-       if (freq_next <= ((policy->cur * 95) / 100))
                __cpufreq_driver_target(policy, freq_next, CPUFREQ_RELATION_L);
+       }
 }
 
 static void do_dbs_timer(void *data)
 {
-       int i;
-       lock_cpu_hotplug();
-       mutex_lock(&dbs_mutex);
-       for_each_online_cpu(i)
-               dbs_check_cpu(i);
-       queue_delayed_work(dbs_workq, &dbs_work,
-                          usecs_to_jiffies(dbs_tuners_ins.sampling_rate));
-       mutex_unlock(&dbs_mutex);
-       unlock_cpu_hotplug();
+       unsigned int cpu = smp_processor_id();
+       struct cpu_dbs_info_s *dbs_info = &per_cpu(cpu_dbs_info, cpu);
+
+       dbs_check_cpu(dbs_info);
+       queue_delayed_work_on(cpu, kondemand_wq, &dbs_info->work,
+                       usecs_to_jiffies(dbs_tuners_ins.sampling_rate));
 }
 
-static inline void dbs_timer_init(void)
+static inline void dbs_timer_init(unsigned int cpu)
 {
-       INIT_WORK(&dbs_work, do_dbs_timer, NULL);
-       if (!dbs_workq)
-               dbs_workq = create_singlethread_workqueue("ondemand");
-       if (!dbs_workq) {
-               printk(KERN_ERR "ondemand: Cannot initialize kernel thread\n");
-               return;
-       }
-       queue_delayed_work(dbs_workq, &dbs_work,
-                          usecs_to_jiffies(dbs_tuners_ins.sampling_rate));
+       struct cpu_dbs_info_s *dbs_info = &per_cpu(cpu_dbs_info, cpu);
+
+       INIT_WORK(&dbs_info->work, do_dbs_timer, 0);
+       queue_delayed_work_on(cpu, kondemand_wq, &dbs_info->work,
+                       usecs_to_jiffies(dbs_tuners_ins.sampling_rate));
        return;
 }
 
-static inline void dbs_timer_exit(void)
+static inline void dbs_timer_exit(unsigned int cpu)
 {
-       if (dbs_workq)
-               cancel_rearming_delayed_workqueue(dbs_workq, &dbs_work);
+       struct cpu_dbs_info_s *dbs_info = &per_cpu(cpu_dbs_info, cpu);
+
+       cancel_rearming_delayed_workqueue(kondemand_wq, &dbs_info->work);
 }
 
 static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
@@ -413,8 +337,7 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
 
        switch (event) {
        case CPUFREQ_GOV_START:
-               if ((!cpu_online(cpu)) ||
-                   (!policy->cur))
+               if ((!cpu_online(cpu)) || (!policy->cur))
                        return -EINVAL;
 
                if (policy->cpuinfo.transition_latency >
@@ -427,18 +350,26 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
                        break;
 
                mutex_lock(&dbs_mutex);
+               dbs_enable++;
+               if (dbs_enable == 1) {
+                       kondemand_wq = create_workqueue("kondemand");
+                       if (!kondemand_wq) {
+                               printk(KERN_ERR "Creation of kondemand failed\n");
+                               dbs_enable--;
+                               mutex_unlock(&dbs_mutex);
+                               return -ENOSPC;
+                       }
+               }
                for_each_cpu_mask(j, policy->cpus) {
                        struct cpu_dbs_info_s *j_dbs_info;
                        j_dbs_info = &per_cpu(cpu_dbs_info, j);
                        j_dbs_info->cur_policy = policy;
 
-                       j_dbs_info->prev_cpu_idle_up = get_cpu_idle_time(j);
-                       j_dbs_info->prev_cpu_idle_down
-                               = j_dbs_info->prev_cpu_idle_up;
+                       j_dbs_info->prev_cpu_idle = get_cpu_idle_time(j);
+                       j_dbs_info->prev_cpu_wall = get_jiffies_64();
                }
                this_dbs_info->enable = 1;
                sysfs_create_group(&policy->kobj, &dbs_attr_group);
-               dbs_enable++;
                /*
                 * Start the timerschedule work, when this governor
                 * is used for first time
@@ -457,23 +388,20 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
                                def_sampling_rate = MIN_STAT_SAMPLING_RATE;
 
                        dbs_tuners_ins.sampling_rate = def_sampling_rate;
-                       dbs_timer_init();
                }
+               dbs_timer_init(policy->cpu);
 
                mutex_unlock(&dbs_mutex);
                break;
 
        case CPUFREQ_GOV_STOP:
                mutex_lock(&dbs_mutex);
+               dbs_timer_exit(policy->cpu);
                this_dbs_info->enable = 0;
                sysfs_remove_group(&policy->kobj, &dbs_attr_group);
                dbs_enable--;
-               /*
-                * Stop the timerschedule work, when this governor
-                * is used for first time
-                */
                if (dbs_enable == 0)
-                       dbs_timer_exit();
+                       destroy_workqueue(kondemand_wq);
 
                mutex_unlock(&dbs_mutex);
 
@@ -483,13 +411,13 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
                lock_cpu_hotplug();
                mutex_lock(&dbs_mutex);
                if (policy->max < this_dbs_info->cur_policy->cur)
-                       __cpufreq_driver_target(
-                                       this_dbs_info->cur_policy,
-                                       policy->max, CPUFREQ_RELATION_H);
+                       __cpufreq_driver_target(this_dbs_info->cur_policy,
+                                               policy->max,
+                                               CPUFREQ_RELATION_H);
                else if (policy->min > this_dbs_info->cur_policy->cur)
-                       __cpufreq_driver_target(
-                                       this_dbs_info->cur_policy,
-                                       policy->min, CPUFREQ_RELATION_L);
+                       __cpufreq_driver_target(this_dbs_info->cur_policy,
+                                               policy->min,
+                                               CPUFREQ_RELATION_L);
                mutex_unlock(&dbs_mutex);
                unlock_cpu_hotplug();
                break;
@@ -498,9 +426,9 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
 }
 
 static struct cpufreq_governor cpufreq_gov_dbs = {
-       .name           = "ondemand",
-       .governor       = cpufreq_governor_dbs,
-       .owner          = THIS_MODULE,
+       .name = "ondemand",
+       .governor = cpufreq_governor_dbs,
+       .owner = THIS_MODULE,
 };
 
 static int __init cpufreq_gov_dbs_init(void)
@@ -510,21 +438,15 @@ static int __init cpufreq_gov_dbs_init(void)
 
 static void __exit cpufreq_gov_dbs_exit(void)
 {
-       /* Make sure that the scheduled work is indeed not running.
-          Assumes the timer has been cancelled first. */
-       if (dbs_workq) {
-               flush_workqueue(dbs_workq);
-               destroy_workqueue(dbs_workq);
-       }
-
        cpufreq_unregister_governor(&cpufreq_gov_dbs);
 }
 
 
-MODULE_AUTHOR ("Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>");
-MODULE_DESCRIPTION ("'cpufreq_ondemand' - A dynamic cpufreq governor for "
-               "Low Latency Frequency Transition capable processors");
-MODULE_LICENSE ("GPL");
+MODULE_AUTHOR("Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>");
+MODULE_AUTHOR("Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>");
+MODULE_DESCRIPTION("'cpufreq_ondemand' - A dynamic cpufreq governor for "
+                   "Low Latency Frequency Transition capable processors");
+MODULE_LICENSE("GPL");
 
 module_init(cpufreq_gov_dbs_init);
 module_exit(cpufreq_gov_dbs_exit);
index 6f17856..09204e4 100644 (file)
@@ -24,7 +24,9 @@ typedef u64 cputime64_t;
 
 #define cputime64_zero (0ULL)
 #define cputime64_add(__a, __b)                ((__a) + (__b))
+#define cputime64_sub(__a, __b)                ((__a) - (__b))
 #define cputime64_to_jiffies64(__ct)   (__ct)
+#define jiffies64_to_cputime64(__jif)  (__jif)
 #define cputime_to_cputime64(__ct)     ((u64) __ct)
 
 
index 957c21c..9bca353 100644 (file)
@@ -63,6 +63,8 @@ extern void destroy_workqueue(struct workqueue_struct *wq);
 
 extern int FASTCALL(queue_work(struct workqueue_struct *wq, struct work_struct *work));
 extern int FASTCALL(queue_delayed_work(struct workqueue_struct *wq, struct work_struct *work, unsigned long delay));
+extern int queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
+       struct work_struct *work, unsigned long delay);
 extern void FASTCALL(flush_workqueue(struct workqueue_struct *wq));
 
 extern int FASTCALL(schedule_work(struct work_struct *work));
index 90d2c60..eebb1d8 100644 (file)
@@ -114,6 +114,7 @@ int fastcall queue_work(struct workqueue_struct *wq, struct work_struct *work)
        put_cpu();
        return ret;
 }
+EXPORT_SYMBOL_GPL(queue_work);
 
 static void delayed_work_timer_fn(unsigned long __data)
 {
@@ -147,6 +148,29 @@ int fastcall queue_delayed_work(struct workqueue_struct *wq,
        }
        return ret;
 }
+EXPORT_SYMBOL_GPL(queue_delayed_work);
+
+int queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
+                       struct work_struct *work, unsigned long delay)
+{
+       int ret = 0;
+       struct timer_list *timer = &work->timer;
+
+       if (!test_and_set_bit(0, &work->pending)) {
+               BUG_ON(timer_pending(timer));
+               BUG_ON(!list_empty(&work->entry));
+
+               /* This stores wq for the moment, for the timer_fn */
+               work->wq_data = wq;
+               timer->expires = jiffies + delay;
+               timer->data = (unsigned long)work;
+               timer->function = delayed_work_timer_fn;
+               add_timer_on(timer, cpu);
+               ret = 1;
+       }
+       return ret;
+}
+EXPORT_SYMBOL_GPL(queue_delayed_work_on);
 
 static void run_workqueue(struct cpu_workqueue_struct *cwq)
 {
@@ -281,6 +305,7 @@ void fastcall flush_workqueue(struct workqueue_struct *wq)
                unlock_cpu_hotplug();
        }
 }
+EXPORT_SYMBOL_GPL(flush_workqueue);
 
 static struct task_struct *create_workqueue_thread(struct workqueue_struct *wq,
                                                   int cpu)
@@ -358,6 +383,7 @@ struct workqueue_struct *__create_workqueue(const char *name,
        }
        return wq;
 }
+EXPORT_SYMBOL_GPL(__create_workqueue);
 
 static void cleanup_workqueue_thread(struct workqueue_struct *wq, int cpu)
 {
@@ -395,6 +421,7 @@ void destroy_workqueue(struct workqueue_struct *wq)
        free_percpu(wq->cpu_wq);
        kfree(wq);
 }
+EXPORT_SYMBOL_GPL(destroy_workqueue);
 
 static struct workqueue_struct *keventd_wq;
 
@@ -402,31 +429,20 @@ int fastcall schedule_work(struct work_struct *work)
 {
        return queue_work(keventd_wq, work);
 }
+EXPORT_SYMBOL(schedule_work);
 
 int fastcall schedule_delayed_work(struct work_struct *work, unsigned long delay)
 {
        return queue_delayed_work(keventd_wq, work, delay);
 }
+EXPORT_SYMBOL(schedule_delayed_work);
 
 int schedule_delayed_work_on(int cpu,
                        struct work_struct *work, unsigned long delay)
 {
-       int ret = 0;
-       struct timer_list *timer = &work->timer;
-
-       if (!test_and_set_bit(0, &work->pending)) {
-               BUG_ON(timer_pending(timer));
-               BUG_ON(!list_empty(&work->entry));
-               /* This stores keventd_wq for the moment, for the timer_fn */
-               work->wq_data = keventd_wq;
-               timer->expires = jiffies + delay;
-               timer->data = (unsigned long)work;
-               timer->function = delayed_work_timer_fn;
-               add_timer_on(timer, cpu);
-               ret = 1;
-       }
-       return ret;
+       return queue_delayed_work_on(cpu, keventd_wq, work, delay);
 }
+EXPORT_SYMBOL(schedule_delayed_work_on);
 
 /**
  * schedule_on_each_cpu - call a function on each online CPU from keventd
@@ -463,6 +479,7 @@ void flush_scheduled_work(void)
 {
        flush_workqueue(keventd_wq);
 }
+EXPORT_SYMBOL(flush_scheduled_work);
 
 /**
  * cancel_rearming_delayed_workqueue - reliably kill off a delayed
@@ -619,13 +636,3 @@ void init_workqueues(void)
        BUG_ON(!keventd_wq);
 }
 
-EXPORT_SYMBOL_GPL(__create_workqueue);
-EXPORT_SYMBOL_GPL(queue_work);
-EXPORT_SYMBOL_GPL(queue_delayed_work);
-EXPORT_SYMBOL_GPL(flush_workqueue);
-EXPORT_SYMBOL_GPL(destroy_workqueue);
-
-EXPORT_SYMBOL(schedule_work);
-EXPORT_SYMBOL(schedule_delayed_work);
-EXPORT_SYMBOL(schedule_delayed_work_on);
-EXPORT_SYMBOL(flush_scheduled_work);