X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=mm%2Fpdflush.c;h=8ce0900dc95ce13052ee6241f7cf6de91f828a8a;hb=8978a318837d7acefca82645017c0534aeba5a36;hp=d6781951267eb654a522529658aaa06199d1772f;hpb=8066eff0a1a0703ad901dbe5646a47dbfc089ef2;p=linux-2.6-omap-h63xx.git

diff --git a/mm/pdflush.c b/mm/pdflush.c
index d6781951267..9d834aa4b97 100644
--- a/mm/pdflush.c
+++ b/mm/pdflush.c
@@ -17,9 +17,11 @@
 #include <linux/gfp.h>
 #include <linux/init.h>
 #include <linux/module.h>
-#include <linux/fs.h>		// Needed by writeback.h
-#include <linux/writeback.h>	// Prototypes pdflush_operation()
+#include <linux/fs.h>		/* Needed by writeback.h	  */
+#include <linux/writeback.h>	/* Prototypes pdflush_operation() */
 #include <linux/kthread.h>
+#include <linux/cpuset.h>
+#include <linux/freezer.h>
 
 
 /*
@@ -89,7 +91,8 @@ struct pdflush_work {
 
 static int __pdflush(struct pdflush_work *my_work)
 {
-	current->flags |= PF_FLUSHER;
+	current->flags |= PF_FLUSHER | PF_SWAPWRITE;
+	set_freezable();
 	my_work->fn = NULL;
 	my_work->who = current;
 	INIT_LIST_HEAD(&my_work->list);
@@ -103,21 +106,20 @@ static int __pdflush(struct pdflush_work *my_work)
 		list_move(&my_work->list, &pdflush_list);
 		my_work->when_i_went_to_sleep = jiffies;
 		spin_unlock_irq(&pdflush_lock);
-
 		schedule();
-		if (try_to_freeze()) {
-			spin_lock_irq(&pdflush_lock);
-			continue;
-		}
-
+		try_to_freeze();
 		spin_lock_irq(&pdflush_lock);
 		if (!list_empty(&my_work->list)) {
-			printk("pdflush: bogus wakeup!\n");
+			/*
+			 * Someone woke us up, but without removing our control
+			 * structure from the global list.  swsusp will do this
+			 * in try_to_freeze()->refrigerator().  Handle it.
+			 */
 			my_work->fn = NULL;
 			continue;
 		}
 		if (my_work->fn == NULL) {
-			printk("pdflush: NULL work function\n");
+			printk("pdflush: bogus wakeup\n");
 			continue;
 		}
 		spin_unlock_irq(&pdflush_lock);
@@ -170,12 +172,24 @@ static int __pdflush(struct pdflush_work *my_work)
 static int pdflush(void *dummy)
 {
 	struct pdflush_work my_work;
+	cpumask_t cpus_allowed;
 
 	/*
 	 * pdflush can spend a lot of time doing encryption via dm-crypt.  We
 	 * don't want to do that at keventd's priority.
 	 */
 	set_user_nice(current, 0);
+
+	/*
+	 * Some configs put our parent kthread in a limited cpuset,
+	 * which kthread() overrides, forcing cpus_allowed == CPU_MASK_ALL.
+	 * Our needs are more modest - cut back to our cpusets cpus_allowed.
+	 * This is needed as pdflush's are dynamically created and destroyed.
+	 * The boottime pdflush's are easily placed w/o these 2 lines.
+	 */
+	cpuset_cpus_allowed(current, &cpus_allowed);
+	set_cpus_allowed_ptr(current, &cpus_allowed);
+
 	return __pdflush(&my_work);
 }
 
@@ -189,12 +203,10 @@ int pdflush_operation(void (*fn)(unsigned long), unsigned long arg0)
 	unsigned long flags;
 	int ret = 0;
 
-	if (fn == NULL)
-		BUG();		/* Hard to diagnose if it's deferred */
+	BUG_ON(fn == NULL);	/* Hard to diagnose if it's deferred */
 
 	spin_lock_irqsave(&pdflush_lock, flags);
 	if (list_empty(&pdflush_list)) {
-		spin_unlock_irqrestore(&pdflush_lock, flags);
 		ret = -1;
 	} else {
 		struct pdflush_work *pdf;
@@ -206,8 +218,9 @@ int pdflush_operation(void (*fn)(unsigned long), unsigned long arg0)
 		pdf->fn = fn;
 		pdf->arg0 = arg0;
 		wake_up_process(pdf->who);
-		spin_unlock_irqrestore(&pdflush_lock, flags);
 	}
+	spin_unlock_irqrestore(&pdflush_lock, flags);
+
 	return ret;
 }