*/
#include <linux/async.h>
+#include <linux/bug.h>
#include <linux/module.h>
#include <linux/wait.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/kthread.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
#include <asm/atomic.h>
static async_cookie_t next_cookie = 1;
static LIST_HEAD(async_running);
static DEFINE_SPINLOCK(async_lock);
+static int async_enabled = 0;
+
struct async_entry {
struct list_head list;
async_cookie_t cookie;
static async_cookie_t __lowest_in_progress(struct list_head *running)
{
struct async_entry *entry;
- if (!list_empty(&async_pending)) {
- entry = list_first_entry(&async_pending,
- struct async_entry, list);
- return entry->cookie;
- } else if (!list_empty(running)) {
+
+ if (!list_empty(running)) {
entry = list_first_entry(running,
struct async_entry, list);
return entry->cookie;
- } else {
- /* nothing in progress... next_cookie is "infinity" */
- return next_cookie;
}
+ list_for_each_entry(entry, &async_pending, list)
+ if (entry->running == running)
+ return entry->cookie;
+
+ return next_cookie; /* "infinity" value */
+}
+
+static async_cookie_t lowest_in_progress(struct list_head *running)
+{
+ unsigned long flags;
+ async_cookie_t ret;
+
+ spin_lock_irqsave(&async_lock, flags);
+ ret = __lowest_in_progress(running);
+ spin_unlock_irqrestore(&async_lock, flags);
+ return ret;
}
/*
* pick the first pending entry and run it
entry = list_first_entry(&async_pending, struct async_entry, list);
/* 2) move it to the running queue */
- list_del(&entry->list);
- list_add_tail(&entry->list, &async_running);
+ list_move_tail(&entry->list, entry->running);
spin_unlock_irqrestore(&async_lock, flags);
/* 3) run it (and print duration)*/
if (initcall_debug && system_state == SYSTEM_BOOTING) {
- printk("calling %lli_%pF @ %i\n", entry->cookie, entry->func, task_pid_nr(current));
+ printk("calling %lli_%pF @ %i\n", (long long)entry->cookie,
+ entry->func, task_pid_nr(current));
calltime = ktime_get();
}
entry->func(entry->data, entry->cookie);
if (initcall_debug && system_state == SYSTEM_BOOTING) {
rettime = ktime_get();
delta = ktime_sub(rettime, calltime);
- printk("initcall %lli_%pF returned 0 after %lld usecs\n", entry->cookie,
- entry->func, ktime_to_ns(delta) >> 10);
+ printk("initcall %lli_%pF returned 0 after %lld usecs\n",
+ (long long)entry->cookie,
+ entry->func,
+ (long long)ktime_to_ns(delta) >> 10);
}
/* 4) remove it from the running queue */
* If we're out of memory or if there's too much work
* pending already, we execute synchronously.
*/
- if (!entry || atomic_read(&entry_count) > MAX_WORK) {
+ if (!async_enabled || !entry || atomic_read(&entry_count) > MAX_WORK) {
kfree(entry);
spin_lock_irqsave(&async_lock, flags);
newcookie = next_cookie++;
return newcookie;
}
+/**
+ * async_schedule - schedule a function for asynchronous execution
+ * @ptr: function to execute asynchronously
+ * @data: data pointer to pass to the function
+ *
+ * Returns an async_cookie_t that may be used for checkpointing later.
+ * Note: This function may be called from atomic or non-atomic contexts.
+ */
async_cookie_t async_schedule(async_func_ptr *ptr, void *data)
{
- return __async_schedule(ptr, data, &async_pending);
+ return __async_schedule(ptr, data, &async_running);
}
EXPORT_SYMBOL_GPL(async_schedule);
-async_cookie_t async_schedule_special(async_func_ptr *ptr, void *data, struct list_head *running)
+/**
+ * async_schedule_domain - schedule a function for asynchronous execution within a certain domain
+ * @ptr: function to execute asynchronously
+ * @data: data pointer to pass to the function
+ * @running: running list for the domain
+ *
+ * Returns an async_cookie_t that may be used for checkpointing later.
+ * @running may be used in the async_synchronize_*_domain() functions
+ * to wait within a certain synchronization domain rather than globally.
+ * A synchronization domain is specified via the running queue @running to use.
+ * Note: This function may be called from atomic or non-atomic contexts.
+ */
+async_cookie_t async_schedule_domain(async_func_ptr *ptr, void *data,
+ struct list_head *running)
{
return __async_schedule(ptr, data, running);
}
-EXPORT_SYMBOL_GPL(async_schedule_special);
+EXPORT_SYMBOL_GPL(async_schedule_domain);
+/**
+ * async_synchronize_full - synchronize all asynchronous function calls
+ *
+ * This function waits until all asynchronous function calls have been done.
+ */
void async_synchronize_full(void)
{
- async_synchronize_cookie(next_cookie);
+ do {
+ async_synchronize_cookie(next_cookie);
+ } while (!list_empty(&async_running) || !list_empty(&async_pending));
}
EXPORT_SYMBOL_GPL(async_synchronize_full);
-void async_synchronize_full_special(struct list_head *list)
+/**
+ * async_synchronize_full_domain - synchronize all asynchronous function within a certain domain
+ * @list: running list to synchronize on
+ *
+ * This function waits until all asynchronous function calls for the
+ * synchronization domain specified by the running list @list have been done.
+ */
+void async_synchronize_full_domain(struct list_head *list)
{
- async_synchronize_cookie_special(next_cookie, list);
+ async_synchronize_cookie_domain(next_cookie, list);
}
-EXPORT_SYMBOL_GPL(async_synchronize_full_special);
+EXPORT_SYMBOL_GPL(async_synchronize_full_domain);
-void async_synchronize_cookie_special(async_cookie_t cookie, struct list_head *running)
+/**
+ * async_synchronize_cookie_domain - synchronize asynchronous function calls within a certain domain with cookie checkpointing
+ * @cookie: async_cookie_t to use as checkpoint
+ * @running: running list to synchronize on
+ *
+ * This function waits until all asynchronous function calls for the
+ * synchronization domain specified by the running list @list submitted
+ * prior to @cookie have been done.
+ */
+void async_synchronize_cookie_domain(async_cookie_t cookie,
+ struct list_head *running)
{
ktime_t starttime, delta, endtime;
starttime = ktime_get();
}
- wait_event(async_done, __lowest_in_progress(running) >= cookie);
+ wait_event(async_done, lowest_in_progress(running) >= cookie);
if (initcall_debug && system_state == SYSTEM_BOOTING) {
endtime = ktime_get();
delta = ktime_sub(endtime, starttime);
printk("async_continuing @ %i after %lli usec\n",
- task_pid_nr(current), ktime_to_ns(delta) >> 10);
+ task_pid_nr(current),
+ (long long)ktime_to_ns(delta) >> 10);
}
}
-EXPORT_SYMBOL_GPL(async_synchronize_cookie_special);
+EXPORT_SYMBOL_GPL(async_synchronize_cookie_domain);
+/**
+ * async_synchronize_cookie - synchronize asynchronous function calls with cookie checkpointing
+ * @cookie: async_cookie_t to use as checkpoint
+ *
+ * This function waits until all asynchronous function calls prior to @cookie
+ * have been done.
+ */
void async_synchronize_cookie(async_cookie_t cookie)
{
- async_synchronize_cookie_special(cookie, &async_running);
+ async_synchronize_cookie_domain(cookie, &async_running);
}
EXPORT_SYMBOL_GPL(async_synchronize_cookie);
ec = atomic_read(&entry_count);
while (tc < ec && tc < MAX_THREADS) {
- kthread_run(async_thread, NULL, "async/%i", tc);
+ if (IS_ERR(kthread_run(async_thread, NULL, "async/%i",
+ tc))) {
+ msleep(100);
+ continue;
+ }
atomic_inc(&thread_count);
tc++;
}
static int __init async_init(void)
{
- kthread_run(async_manager_thread, NULL, "async/mgr");
+ async_enabled =
+ !IS_ERR(kthread_run(async_manager_thread, NULL, "async/mgr"));
+
+ WARN_ON(!async_enabled);
return 0;
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff