X-Git-Url: http://git.madism.org/?p=~madcoder%2Fpwqr.git;a=blobdiff_plain;f=kernel%2Fpwqr.c;h=e4e3f58a872b146af038b8cffc9a5c6f2ca5ab0a;hp=4d4c4cd10b5a8112c4e57c367287dcf89e2b1aa9;hb=b29ccbcc4ab80bc7e7b2131349459cc9e96d49ef;hpb=006df851760b087ea18222f4c417756cbf69b2ea;ds=sidebyside

diff --git a/kernel/pwqr.c b/kernel/pwqr.c
index 4d4c4cd..e4e3f58 100644
--- a/kernel/pwqr.c
+++ b/kernel/pwqr.c
@@ -29,6 +29,7 @@
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
+#include <linux/timer.h>
 #include <linux/uaccess.h>
 #include <linux/wait.h>
 
@@ -38,6 +39,7 @@
 
 #include "pwqr.h"
 
+#define PWQR_UNPARK_DELAY	(HZ / 10)
 #define PWQR_HASH_BITS		5
 #define PWQR_HASH_SIZE		(1 << PWQR_HASH_BITS)
 
@@ -49,6 +51,7 @@ struct pwqr_task_bucket {
 struct pwqr_sb {
 	struct kref		kref;
 	struct rcu_head		rcu;
+	struct timer_list	timer;
 	wait_queue_head_t	wqh;
 	pid_t			tgid;
 
@@ -97,10 +100,9 @@ static inline void __pwqr_sb_update_state(struct pwqr_sb *sb, int running_delta)
 
 	sb->running += running_delta;
 	overcommit = sb->running + sb->waiting - sb->concurrency;
-	if (overcommit == 0)
-		return;
-
-	if (overcommit > 0) {
+	if (overcommit == 0) {
+		/* do nothing */
+	} else if (overcommit > 0) {
 		if (overcommit > sb->waiting) {
 			sb->quarantined += sb->waiting;
 			sb->waiting      = 0;
@@ -118,9 +120,29 @@ static inline void __pwqr_sb_update_state(struct pwqr_sb *sb, int running_delta)
 			sb->waiting     += sb->quarantined;
 			sb->quarantined  = 0;
 		} else if (sb->waiting == 0 && sb->parked) {
-			wake_up_locked(&sb->wqh);
+			if (!timer_pending(&sb->timer)) {
+				mod_timer(&sb->timer, jiffies +
+					  PWQR_UNPARK_DELAY);
+			}
+			return;
 		}
 	}
+
+	if (timer_pending(&sb->timer))
+		del_timer(&sb->timer);
+}
+
+static void pwqr_sb_timer_cb(unsigned long arg)
+{
+	struct pwqr_sb *sb = (struct pwqr_sb *)arg;
+	unsigned long flags;
+
+	pwqr_sb_lock_irqsave(sb, flags);
+	if (sb->waiting == 0 && sb->parked && sb->running < sb->concurrency) {
+		if (sb->overcommit_wakes == 0)
+			wake_up_locked(&sb->wqh);
+	}
+	pwqr_sb_unlock_irqrestore(sb, flags);
 }
 
 static struct pwqr_sb *pwqr_sb_create(void)
@@ -135,6 +157,9 @@ static struct pwqr_sb *pwqr_sb_create(void)
 	init_waitqueue_head(&sb->wqh);
 	sb->tgid        = current->tgid;
 	sb->concurrency = num_online_cpus();
+	init_timer(&sb->timer);
+	sb->timer.function = pwqr_sb_timer_cb;
+	sb->timer.data     = (unsigned long)sb;
 
 	__module_get(THIS_MODULE);
 	return sb;
@@ -156,6 +181,7 @@ static void pwqr_sb_release(struct kref *kref)
 {
 	struct pwqr_sb *sb = container_of(kref, struct pwqr_sb, kref);
 
+	del_timer_sync(&sb->timer);
 	call_rcu(&sb->rcu, pwqr_sb_finalize);
 }
 static inline void pwqr_sb_put(struct pwqr_sb *sb)