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-rw-r--r--kernel/slow-work.c44
1 files changed, 33 insertions, 11 deletions
diff --git a/kernel/slow-work.c b/kernel/slow-work.c
index f67e1daae93..b763bc2d267 100644
--- a/kernel/slow-work.c
+++ b/kernel/slow-work.c
@@ -16,13 +16,8 @@
#include <linux/kthread.h>
#include <linux/freezer.h>
#include <linux/wait.h>
-
-#define SLOW_WORK_CULL_TIMEOUT (5 * HZ) /* cull threads 5s after running out of
- * things to do */
-#define SLOW_WORK_OOM_TIMEOUT (5 * HZ) /* can't start new threads for 5s after
- * OOM */
-
-#define SLOW_WORK_THREAD_LIMIT 255 /* abs maximum number of slow-work threads */
+#include <linux/proc_fs.h>
+#include "slow-work.h"
static void slow_work_cull_timeout(unsigned long);
static void slow_work_oom_timeout(unsigned long);
@@ -117,6 +112,15 @@ static DEFINE_MUTEX(slow_work_unreg_sync_lock);
#endif
/*
+ * Data for tracking currently executing items for indication through /proc
+ */
+#ifdef CONFIG_SLOW_WORK_PROC
+struct slow_work *slow_work_execs[SLOW_WORK_THREAD_LIMIT];
+pid_t slow_work_pids[SLOW_WORK_THREAD_LIMIT];
+DEFINE_RWLOCK(slow_work_execs_lock);
+#endif
+
+/*
* The queues of work items and the lock governing access to them. These are
* shared between all the CPUs. It doesn't make sense to have per-CPU queues
* as the number of threads bears no relation to the number of CPUs.
@@ -124,9 +128,9 @@ static DEFINE_MUTEX(slow_work_unreg_sync_lock);
* There are two queues of work items: one for slow work items, and one for
* very slow work items.
*/
-static LIST_HEAD(slow_work_queue);
-static LIST_HEAD(vslow_work_queue);
-static DEFINE_SPINLOCK(slow_work_queue_lock);
+LIST_HEAD(slow_work_queue);
+LIST_HEAD(vslow_work_queue);
+DEFINE_SPINLOCK(slow_work_queue_lock);
/*
* The thread controls. A variable used to signal to the threads that they
@@ -182,7 +186,7 @@ static unsigned slow_work_calc_vsmax(void)
* Attempt to execute stuff queued on a slow thread. Return true if we managed
* it, false if there was nothing to do.
*/
-static bool slow_work_execute(int id)
+static noinline bool slow_work_execute(int id)
{
#ifdef CONFIG_MODULES
struct module *module;
@@ -227,6 +231,10 @@ static bool slow_work_execute(int id)
if (work)
slow_work_thread_processing[id] = work->owner;
#endif
+ if (work) {
+ slow_work_mark_time(work);
+ slow_work_begin_exec(id, work);
+ }
spin_unlock_irq(&slow_work_queue_lock);
@@ -247,6 +255,8 @@ static bool slow_work_execute(int id)
/* wake up anyone waiting for this work to be complete */
wake_up_bit(&work->flags, SLOW_WORK_EXECUTING);
+ slow_work_end_exec(id, work);
+
/* if someone tried to enqueue the item whilst we were executing it,
* then it'll be left unenqueued to avoid multiple threads trying to
* execute it simultaneously
@@ -285,6 +295,7 @@ auto_requeue:
* - we transfer our ref on the item back to the appropriate queue
* - don't wake another thread up as we're awake already
*/
+ slow_work_mark_time(work);
if (test_bit(SLOW_WORK_VERY_SLOW, &work->flags))
list_add_tail(&work->link, &vslow_work_queue);
else
@@ -368,6 +379,7 @@ int slow_work_enqueue(struct slow_work *work)
ret = slow_work_get_ref(work);
if (ret < 0)
goto failed;
+ slow_work_mark_time(work);
if (test_bit(SLOW_WORK_VERY_SLOW, &work->flags))
list_add_tail(&work->link, &vslow_work_queue);
else
@@ -489,6 +501,7 @@ static void delayed_slow_work_timer(unsigned long data)
set_bit(SLOW_WORK_ENQ_DEFERRED, &work->flags);
put = true;
} else {
+ slow_work_mark_time(work);
if (test_bit(SLOW_WORK_VERY_SLOW, &work->flags))
list_add_tail(&work->link, &vslow_work_queue);
else
@@ -627,6 +640,7 @@ static int slow_work_thread(void *_data)
id = find_first_zero_bit(slow_work_ids, SLOW_WORK_THREAD_LIMIT);
BUG_ON(id < 0 || id >= SLOW_WORK_THREAD_LIMIT);
__set_bit(id, slow_work_ids);
+ slow_work_set_thread_pid(id, current->pid);
spin_unlock_irq(&slow_work_queue_lock);
sprintf(current->comm, "kslowd%03u", id);
@@ -669,6 +683,7 @@ static int slow_work_thread(void *_data)
}
spin_lock_irq(&slow_work_queue_lock);
+ slow_work_set_thread_pid(id, 0);
__clear_bit(id, slow_work_ids);
spin_unlock_irq(&slow_work_queue_lock);
@@ -722,6 +737,9 @@ static void slow_work_new_thread_execute(struct slow_work *work)
static const struct slow_work_ops slow_work_new_thread_ops = {
.owner = THIS_MODULE,
.execute = slow_work_new_thread_execute,
+#ifdef CONFIG_SLOW_WORK_PROC
+ .desc = slow_work_new_thread_desc,
+#endif
};
/*
@@ -949,6 +967,10 @@ static int __init init_slow_work(void)
if (slow_work_max_max_threads < nr_cpus * 2)
slow_work_max_max_threads = nr_cpus * 2;
#endif
+#ifdef CONFIG_SLOW_WORK_PROC
+ proc_create("slow_work_rq", S_IFREG | 0400, NULL,
+ &slow_work_runqueue_fops);
+#endif
return 0;
}