[PATCH 1/4] Task notifier against mm: Allow notifier to remove itself

[PATCH 1/4] Task notifier against mm: Allow notifier to remove itself

[Christoph Lameter]

Patch for Pavel against 2.6.13-rc3-mm3 (after removal of the TIF_FREEZE 
patch). The same patch was posted yesterday against 2.6.13-rc3. I verified
again that this patch works fine on i386.

---

Allow notifier to remove itself.
This is done by retrieving the pointer to the next notifier from the list before the
notifier call. 

Signed-off-by: Christoph Lameter <christoph@lameter.com>

Index: linux-2.6.13-rc3-mm3/kernel/sys.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/kernel/sys.c	2005-07-29 10:38:39.000000000 -0700
+++ linux-2.6.13-rc3-mm3/kernel/sys.c	2005-07-29 12:29:18.000000000 -0700
@@ -172,15 +172,18 @@
 {
 	int ret=NOTIFY_DONE;
 	struct notifier_block *nb = *n;
+	struct notifier_block *next;
 
 	while(nb)
 	{
-		ret=nb->notifier_call(nb,val,v);
+		/* Determining next here allows the notifier to unregister itself */
+		next = nb->next;
+		ret = nb->notifier_call(nb,val,v);
 		if(ret&NOTIFY_STOP_MASK)
 		{
 			return ret;
 		}
-		nb=nb->next;
+		nb = next;
 	}
 	return ret;
 }

[PATCH 2/4] Task notifier against mm: Implement todo list in task_struct

[Christoph Lameter]

Introduce a todo notifier in the task_struct so that a task can be told to do
certain things. Abuse the suspend hooks try_to_freeze, freezing and refrigerator
to establish checkpoints where the todo list is processed. This will break software
suspend (next patch fixes and cleans up software suspend).

Signed-off-by: Christoph Lameter <christoph@lameter.com>

Index: linux-2.6.13-rc3-mm3/include/linux/sched.h
===================================================================
--- linux-2.6.13-rc3-mm3.orig/include/linux/sched.h	2005-07-29 12:32:17.000000000 -0700
+++ linux-2.6.13-rc3-mm3/include/linux/sched.h	2005-07-29 12:37:44.000000000 -0700
@@ -35,6 +35,7 @@
 #include <linux/topology.h>
 #include <linux/seccomp.h>
 #include <linux/taskdelays.h>
+#include <linux/notifier.h>
 
 #include <linux/auxvec.h>	/* For AT_VECTOR_SIZE */
 
@@ -783,7 +784,10 @@
 	int (*notifier)(void *priv);
 	void *notifier_data;
 	sigset_t *notifier_mask;
-	
+
+	/* todo list to be executed in the context of this thread */
+	struct notifier_block *todo;
+
 	void *security;
 	struct audit_context *audit_context;
 	seccomp_t seccomp;
@@ -1353,79 +1357,36 @@
 
 #endif
 
-#ifdef CONFIG_PM
-/*
- * Check if a process has been frozen
- */
-static inline int frozen(struct task_struct *p)
-{
-	return p->flags & PF_FROZEN;
-}
-
-/*
- * Check if there is a request to freeze a process
- */
-static inline int freezing(struct task_struct *p)
-{
-	return p->flags & PF_FREEZE;
-}
-
-/*
- * Request that a process be frozen
- * FIXME: SMP problem. We may not modify other process' flags!
- */
-static inline void freeze(struct task_struct *p)
-{
-	p->flags |= PF_FREEZE;
-}
-
 /*
- * Wake up a frozen process
+ * Check if there is a todo list request
  */
-static inline int thaw_process(struct task_struct *p)
+static inline int todo_list_active(void)
 {
-	if (frozen(p)) {
-		p->flags &= ~PF_FROZEN;
-		wake_up_process(p);
-		return 1;
-	}
-	return 0;
+	return current->todo != NULL;
 }
 
-/*
- * freezing is complete, mark process as frozen
- */
-static inline void frozen_process(struct task_struct *p)
+static inline void run_todo_list(void)
 {
-	p->flags = (p->flags & ~PF_FREEZE) | PF_FROZEN;
+	notifier_call_chain(&current->todo, 0, current);
 }
 
-extern void refrigerator(void);
-extern int freeze_processes(void);
-extern void thaw_processes(void);
-
-static inline int try_to_freeze(void)
+static inline int try_todo_list(void)
 {
-	if (freezing(current)) {
-		refrigerator();
+	if (todo_list_active()) {
+        	run_todo_list();
 		return 1;
 	} else
 		return 0;
 }
-#else
-static inline int frozen(struct task_struct *p) { return 0; }
-static inline int freezing(struct task_struct *p) { return 0; }
-static inline void freeze(struct task_struct *p) { BUG(); }
-static inline int thaw_process(struct task_struct *p) { return 1; }
-static inline void frozen_process(struct task_struct *p) { BUG(); }
-
-static inline void refrigerator(void) {}
-static inline int freeze_processes(void) { BUG(); return 0; }
-static inline void thaw_processes(void) {}
-
-static inline int try_to_freeze(void) { return 0; }
 
-#endif /* CONFIG_PM */
+/*
+ * Compatibility definitions to use the suspend checkpoints for the task todo list.
+ * These may be removed once all uses of try_to_free,  refrigerator and freezing
+ * have been removed.
+ */
+#define try_to_freeze try_todo_list
+#define refrigerator run_todo_list
+#define freezing(p) todo_list_active()
 
 /* API for registering delay info */
 #ifdef CONFIG_DELAY_ACCT
Index: linux-2.6.13-rc3-mm3/kernel/signal.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/kernel/signal.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/kernel/signal.c	2005-07-29 12:32:32.000000000 -0700
@@ -213,7 +213,7 @@
 fastcall void recalc_sigpending_tsk(struct task_struct *t)
 {
 	if (t->signal->group_stop_count > 0 ||
-	    (freezing(t)) ||
+	    (t->todo) ||
 	    PENDING(&t->pending, &t->blocked) ||
 	    PENDING(&t->signal->shared_pending, &t->blocked))
 		set_tsk_thread_flag(t, TIF_SIGPENDING);
@@ -2231,7 +2231,7 @@
 			current->state = TASK_INTERRUPTIBLE;
 			timeout = schedule_timeout(timeout);
 
-			try_to_freeze();
+			try_todo_list();
 			spin_lock_irq(&current->sighand->siglock);
 			sig = dequeue_signal(current, &these, &info);
 			current->blocked = current->real_blocked;
Index: linux-2.6.13-rc3-mm3/arch/frv/kernel/signal.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/arch/frv/kernel/signal.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/arch/frv/kernel/signal.c	2005-07-29 12:32:32.000000000 -0700
@@ -536,7 +536,7 @@
 	if (!user_mode(regs))
 		return 1;
 
-	if (try_to_freeze())
+	if (try_todo_list())
 		goto no_signal;
 
 	if (!oldset)
Index: linux-2.6.13-rc3-mm3/arch/h8300/kernel/signal.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/arch/h8300/kernel/signal.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/arch/h8300/kernel/signal.c	2005-07-29 12:32:32.000000000 -0700
@@ -517,7 +517,7 @@
 	if ((regs->ccr & 0x10))
 		return 1;
 
-	if (try_to_freeze())
+	if (try_todo_list())
 		goto no_signal;
 
 	current->thread.esp0 = (unsigned long) regs;
Index: linux-2.6.13-rc3-mm3/arch/i386/kernel/io_apic.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/arch/i386/kernel/io_apic.c	2005-07-29 12:32:11.000000000 -0700
+++ linux-2.6.13-rc3-mm3/arch/i386/kernel/io_apic.c	2005-07-29 12:32:32.000000000 -0700
@@ -575,7 +575,7 @@
 	for ( ; ; ) {
 		set_current_state(TASK_INTERRUPTIBLE);
 		time_remaining = schedule_timeout(time_remaining);
-		try_to_freeze();
+		try_todo_list();
 		if (time_after(jiffies,
 				prev_balance_time+balanced_irq_interval)) {
 			preempt_disable();
Index: linux-2.6.13-rc3-mm3/arch/i386/kernel/signal.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/arch/i386/kernel/signal.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/arch/i386/kernel/signal.c	2005-07-29 12:32:32.000000000 -0700
@@ -608,7 +608,7 @@
 	if (!user_mode(regs))
 		return 1;
 
-	if (try_to_freeze())
+	if (try_todo_list())
 		goto no_signal;
 
 	if (!oldset)
Index: linux-2.6.13-rc3-mm3/arch/m32r/kernel/signal.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/arch/m32r/kernel/signal.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/arch/m32r/kernel/signal.c	2005-07-29 12:32:32.000000000 -0700
@@ -371,7 +371,7 @@
 	if (!user_mode(regs))
 		return 1;
 
-	if (try_to_freeze()) 
+	if (try_todo_list())
 		goto no_signal;
 
 	if (!oldset)
Index: linux-2.6.13-rc3-mm3/arch/ppc/kernel/signal.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/arch/ppc/kernel/signal.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/arch/ppc/kernel/signal.c	2005-07-29 12:32:32.000000000 -0700
@@ -705,7 +705,7 @@
 	unsigned long frame, newsp;
 	int signr, ret;
 
-	if (try_to_freeze()) {
+	if (try_todo_list()) {
 		signr = 0;
 		if (!signal_pending(current))
 			goto no_signal;
Index: linux-2.6.13-rc3-mm3/arch/x86_64/kernel/signal.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/arch/x86_64/kernel/signal.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/arch/x86_64/kernel/signal.c	2005-07-29 12:32:32.000000000 -0700
@@ -425,7 +425,7 @@
 	if (!user_mode(regs))
 		return 1;
 
-	if (try_to_freeze())
+	if (try_todo_list())
 		goto no_signal;
 
 	if (!oldset)

[PATCH 3/4] Task notifier against mm: Make suspend code SMP safe using todo list

[Christoph Lameter]

Make the suspend code use the todo list in the task_struct

This patch makes the suspend code SMP clean by removing PF_FREEZE and PF_FROZEN. Instead
it relies on the new notification handler in the task_struct, a completion handler and an
atomic counter for the number of processes frozen. All the logic is local to the
suspend code and no longer requires changes to other kernel components.

Signed-off-by: Christoph Lameter <christoph@lameter.com>

Index: linux-2.6.13-rc3-mm3/include/linux/sched.h
===================================================================
--- linux-2.6.13-rc3-mm3.orig/include/linux/sched.h	2005-07-29 12:37:44.000000000 -0700
+++ linux-2.6.13-rc3-mm3/include/linux/sched.h	2005-07-29 12:37:59.000000000 -0700
@@ -890,9 +890,7 @@
 #define PF_MEMALLOC	0x00000800	/* Allocating memory */
 #define PF_FLUSHER	0x00001000	/* responsible for disk writeback */
 #define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
-#define PF_FREEZE	0x00004000	/* this task is being frozen for suspend now */
 #define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
-#define PF_FROZEN	0x00010000	/* frozen for system suspend */
 #define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
 #define PF_KSWAPD	0x00040000	/* I am kswapd */
 #define PF_SWAPOFF	0x00080000	/* I am in swapoff */
Index: linux-2.6.13-rc3-mm3/kernel/power/process.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/kernel/power/process.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/kernel/power/process.c	2005-07-29 12:37:59.000000000 -0700
@@ -18,6 +18,8 @@
  */
 #define TIMEOUT	(6 * HZ)
 
+DECLARE_COMPLETION(thaw);
+static atomic_t nr_frozen;
 
 static inline int freezeable(struct task_struct * p)
 {
@@ -31,26 +33,36 @@
 	return 1;
 }
 
-/* Refrigerator is place where frozen processes are stored :-). */
-void refrigerator(void)
+static int freeze_process(struct notifier_block *nl, unsigned long x, void *v)
 {
 	/* Hmm, should we be allowed to suspend when there are realtime
 	   processes around? */
 	long save;
 	save = current->state;
-	current->state = TASK_UNINTERRUPTIBLE;
-	pr_debug("%s entered refrigerator\n", current->comm);
+	pr_debug("%s frozen\n", current->comm);
 	printk("=");
 
-	frozen_process(current);
 	spin_lock_irq(&current->sighand->siglock);
 	recalc_sigpending(); /* We sent fake signal, clean it up */
+	atomic_inc(&nr_frozen);
 	spin_unlock_irq(&current->sighand->siglock);
 
-	while (frozen(current))
-		schedule();
-	pr_debug("%s left refrigerator\n", current->comm);
+	wait_for_completion(&thaw);
+	atomic_dec(&nr_frozen);
+	notifier_chain_unregister(&current->todo, nl);
+	kfree(nl);
+	pr_debug("%s thawed\n", current->comm);
 	current->state = save;
+	return 0;
+}
+
+void thaw_processes(void)
+{
+	printk( "Restarting tasks..." );
+	complete_all(&thaw);
+	while (atomic_read(&nr_frozen) > 0)
+		schedule();
+	printk( " done\n" );
 }
 
 /* 0 = success, else # of processes that we failed to stop */
@@ -61,19 +73,32 @@
 	struct task_struct *g, *p;
 	unsigned long flags;
 
+	atomic_set(&nr_frozen, 0);
+	INIT_COMPLETION(thaw);
+
 	printk( "Stopping tasks: " );
 	start_time = jiffies;
 	do {
 		todo = 0;
 		read_lock(&tasklist_lock);
 		do_each_thread(g, p) {
+			struct notifier_block *n;
+
 			if (!freezeable(p))
 				continue;
-			if (frozen(p))
-				continue;
 
-			freeze(p);
+			/* If there is nothing on the todo list then get the process to freeze itself */
+			if (!todo_list_active()) {
+				n = kmalloc(sizeof(struct notifier_block), GFP_ATOMIC);
+				if (n) {
+					n->notifier_call = freeze_process;
+					n->priority = 0;
+					notifier_chain_register(&g->todo, n);
+				}
+		 	}
+			/* Make the process work on its todo list */
 			spin_lock_irqsave(&p->sighand->siglock, flags);
+			recalc_sigpending();
 			signal_wake_up(p, 0);
 			spin_unlock_irqrestore(&p->sighand->siglock, flags);
 			todo++;
@@ -83,31 +108,13 @@
 		if (time_after(jiffies, start_time + TIMEOUT)) {
 			printk( "\n" );
 			printk(KERN_ERR " stopping tasks failed (%d tasks remaining)\n", todo );
+			thaw_processes();
 			return todo;
 		}
-	} while(todo);
+	} while(todo < atomic_read(&nr_frozen));
 
 	printk( "|\n" );
 	BUG_ON(in_atomic());
 	return 0;
 }
 
-void thaw_processes(void)
-{
-	struct task_struct *g, *p;
-
-	printk( "Restarting tasks..." );
-	read_lock(&tasklist_lock);
-	do_each_thread(g, p) {
-		if (!freezeable(p))
-			continue;
-		if (!thaw_process(p))
-			printk(KERN_INFO " Strange, %s not stopped\n", p->comm );
-	} while_each_thread(g, p);
-
-	read_unlock(&tasklist_lock);
-	schedule();
-	printk( " done\n" );
-}
-
-EXPORT_SYMBOL(refrigerator);
Index: linux-2.6.13-rc3-mm3/Documentation/power/kernel_threads.txt
===================================================================
--- linux-2.6.13-rc3-mm3.orig/Documentation/power/kernel_threads.txt	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/Documentation/power/kernel_threads.txt	2005-07-29 12:37:59.000000000 -0700
@@ -4,15 +4,15 @@
 Freezer
 
 Upon entering a suspended state the system will freeze all
-tasks. This is done by delivering pseudosignals. This affects
-kernel threads, too. To successfully freeze a kernel thread
-the thread has to check for the pseudosignal and enter the
-refrigerator. Code to do this looks like this:
+tasks. This is done by making all processes execute a notifier.
+This affects kernel threads, too. To successfully freeze a kernel thread
+the thread has to check for the notifications and call the notifier
+chain for the process. Code to do this looks like this:
 
 	do {
 		hub_events();
 		wait_event_interruptible(khubd_wait, !list_empty(&hub_event_list));
-		try_to_freeze();
+		try_todo_list();
 	} while (!signal_pending(current));
 
 from drivers/usb/core/hub.c::hub_thread()
Index: linux-2.6.13-rc3-mm3/Documentation/power/swsusp.txt
===================================================================
--- linux-2.6.13-rc3-mm3.orig/Documentation/power/swsusp.txt	2005-07-29 12:32:11.000000000 -0700
+++ linux-2.6.13-rc3-mm3/Documentation/power/swsusp.txt	2005-07-29 12:37:59.000000000 -0700
@@ -155,7 +155,8 @@
 website, and not to the Linux Kernel Mailing List. We are working
 toward merging suspend2 into the mainline kernel.
 
-Q: A kernel thread must voluntarily freeze itself (call 'refrigerator').
+Q: A kernel thread must work on the todo list (call 'run_todo_list')
+to enter the refrigerator.
 I found some kernel threads that don't do it, and they don't freeze
 so the system can't sleep. Is this a known behavior?
 
@@ -164,7 +165,7 @@
 should be held at that point and it must be safe to sleep there), and
 add:
 
-       try_to_freeze();
+       try_todo_list();
 
 If the thread is needed for writing the image to storage, you should
 instead set the PF_NOFREEZE process flag when creating the thread (and

[PATCH 4/4] Task notifier against mm: s/try_to_freeze/try_todo_list in some driver

[Christoph Lameter]

Patch to replace try_to_freeze with try_todo_list 

Replaces:

try_to_freeze -> try_todo_list
freezing -> todo_listactive
refrigerator -> run_todo_list

This patch is incomplete. Drivers may continue using try_to_freeze, freezing
and refrigerators since the above mapping is also provided by macros in
include/linux/sched.h.

At some point--when all drivers have been changed--the macros in include/linux/sched.h
may be removed.

Signed-off-by: Christoph Lameter <christoph@lameter.com>

Index: linux-2.6.13-rc3-mm3/drivers/block/pktcdvd.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/drivers/block/pktcdvd.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/drivers/block/pktcdvd.c	2005-07-29 12:38:02.000000000 -0700
@@ -1250,8 +1250,7 @@
 			residue = schedule_timeout(min_sleep_time);
 			VPRINTK("kcdrwd: wake up\n");
 
-			/* make swsusp happy with our thread */
-			try_to_freeze();
+			try_todo_list();
 
 			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
 				if (!pkt->sleep_time)
Index: linux-2.6.13-rc3-mm3/drivers/ieee1394/ieee1394_core.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/drivers/ieee1394/ieee1394_core.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/drivers/ieee1394/ieee1394_core.c	2005-07-29 12:38:03.000000000 -0700
@@ -1044,7 +1044,7 @@
 
 	while (1) {
 		if (down_interruptible(&khpsbpkt_sig)) {
-			if (try_to_freeze())
+			if (try_todo_list())
 				continue;
 			printk("khpsbpkt: received unexpected signal?!\n" );
 			break;
Index: linux-2.6.13-rc3-mm3/drivers/ieee1394/nodemgr.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/drivers/ieee1394/nodemgr.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/drivers/ieee1394/nodemgr.c	2005-07-29 12:38:03.000000000 -0700
@@ -1510,7 +1510,7 @@
 
 		if (down_interruptible(&hi->reset_sem) ||
 		    down_interruptible(&nodemgr_serialize)) {
-			if (try_to_freeze())
+			if (try_todo_list())
 				continue;
 			printk("NodeMgr: received unexpected signal?!\n" );
 			break;
Index: linux-2.6.13-rc3-mm3/drivers/input/gameport/gameport.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/drivers/input/gameport/gameport.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/drivers/input/gameport/gameport.c	2005-07-29 12:38:03.000000000 -0700
@@ -435,7 +435,7 @@
 		gameport_handle_events();
 		wait_event_interruptible(gameport_wait,
 			kthread_should_stop() || !list_empty(&gameport_event_list));
-		try_to_freeze();
+		try_todo_list();
 	} while (!kthread_should_stop());
 
 	printk(KERN_DEBUG "gameport: kgameportd exiting\n");
Index: linux-2.6.13-rc3-mm3/drivers/input/serio/serio.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/drivers/input/serio/serio.c	2005-07-29 12:32:06.000000000 -0700
+++ linux-2.6.13-rc3-mm3/drivers/input/serio/serio.c	2005-07-29 12:38:03.000000000 -0700
@@ -371,7 +371,7 @@
 		serio_handle_events();
 		wait_event_interruptible(serio_wait,
 			kthread_should_stop() || !list_empty(&serio_event_list));
-		try_to_freeze();
+		try_todo_list();
 	} while (!kthread_should_stop());
 
 	printk(KERN_DEBUG "serio: kseriod exiting\n");
Index: linux-2.6.13-rc3-mm3/drivers/media/dvb/dvb-core/dvb_frontend.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/drivers/media/dvb/dvb-core/dvb_frontend.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/drivers/media/dvb/dvb-core/dvb_frontend.c	2005-07-29 12:38:03.000000000 -0700
@@ -394,7 +394,7 @@
 			break;
 		}
 
-		try_to_freeze();
+		try_todo_list();
 
 		if (down_interruptible(&fepriv->sem))
 			break;
Index: linux-2.6.13-rc3-mm3/drivers/net/irda/stir4200.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/drivers/net/irda/stir4200.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/drivers/net/irda/stir4200.c	2005-07-29 12:38:03.000000000 -0700
@@ -763,7 +763,7 @@
 	{
 #ifdef CONFIG_PM
 		/* if suspending, then power off and wait */
-		if (unlikely(freezing(current))) {
+		if (unlikely(todo_list_active())) {
 			if (stir->receiving)
 				receive_stop(stir);
 			else
@@ -771,7 +771,7 @@
 
 			write_reg(stir, REG_CTRL1, CTRL1_TXPWD|CTRL1_RXPWD);
 
-			refrigerator();
+			run_todo_list();
 
 			if (change_speed(stir, stir->speed))
 				break;
Index: linux-2.6.13-rc3-mm3/drivers/pcmcia/cs.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/drivers/pcmcia/cs.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/drivers/pcmcia/cs.c	2005-07-29 12:38:03.000000000 -0700
@@ -683,7 +683,7 @@
 		}
 
 		schedule();
-		try_to_freeze();
+		try_todo_list();
 
 		if (!skt->thread)
 			break;
Index: linux-2.6.13-rc3-mm3/drivers/usb/core/hub.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/drivers/usb/core/hub.c	2005-07-29 12:32:11.000000000 -0700
+++ linux-2.6.13-rc3-mm3/drivers/usb/core/hub.c	2005-07-29 12:38:03.000000000 -0700
@@ -2812,7 +2812,7 @@
 		wait_event_interruptible(khubd_wait,
 				!list_empty(&hub_event_list) ||
 				kthread_should_stop());
-		try_to_freeze();
+		try_todo_list();
 	} while (!kthread_should_stop() || !list_empty(&hub_event_list));
 
 	pr_debug("%s: khubd exiting\n", usbcore_name);
Index: linux-2.6.13-rc3-mm3/drivers/usb/storage/usb.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/drivers/usb/storage/usb.c	2005-07-29 12:32:07.000000000 -0700
+++ linux-2.6.13-rc3-mm3/drivers/usb/storage/usb.c	2005-07-29 12:38:03.000000000 -0700
@@ -891,7 +891,7 @@
 		wait_event_interruptible_timeout(us->delay_wait,
 				test_bit(US_FLIDX_DISCONNECTING, &us->flags),
 				delay_use * HZ);
-		if (try_to_freeze())
+		if (try_todo_list())
 			goto retry;
 	}
 
Index: linux-2.6.13-rc3-mm3/fs/afs/kafsasyncd.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/fs/afs/kafsasyncd.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/fs/afs/kafsasyncd.c	2005-07-29 12:38:03.000000000 -0700
@@ -116,7 +116,7 @@
 		remove_wait_queue(&kafsasyncd_sleepq, &myself);
 		set_current_state(TASK_RUNNING);
 
-		try_to_freeze();
+		try_todo_list();
 
 		/* discard pending signals */
 		afs_discard_my_signals();
Index: linux-2.6.13-rc3-mm3/fs/afs/kafstimod.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/fs/afs/kafstimod.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/fs/afs/kafstimod.c	2005-07-29 12:38:03.000000000 -0700
@@ -91,7 +91,7 @@
 			complete_and_exit(&kafstimod_dead, 0);
 		}
 
-		try_to_freeze();
+		try_todo_list();
 
 		/* discard pending signals */
 		afs_discard_my_signals();
Index: linux-2.6.13-rc3-mm3/fs/jbd/journal.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/fs/jbd/journal.c	2005-07-29 12:32:17.000000000 -0700
+++ linux-2.6.13-rc3-mm3/fs/jbd/journal.c	2005-07-29 12:38:03.000000000 -0700
@@ -153,7 +153,7 @@
 	}
 
 	wake_up(&journal->j_wait_done_commit);
-	if (freezing(current)) {
+	if (todo_list_active()) {
 		/*
 		 * The simpler the better. Flushing journal isn't a
 		 * good idea, because that depends on threads that may
@@ -161,7 +161,7 @@
 		 */
 		jbd_debug(1, "Now suspending kjournald\n");
 		spin_unlock(&journal->j_state_lock);
-		refrigerator();
+		run_todo_list();
 		spin_lock(&journal->j_state_lock);
 	} else {
 		/*
Index: linux-2.6.13-rc3-mm3/fs/jfs/jfs_logmgr.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/fs/jfs/jfs_logmgr.c	2005-07-29 12:32:01.000000000 -0700
+++ linux-2.6.13-rc3-mm3/fs/jfs/jfs_logmgr.c	2005-07-29 12:38:03.000000000 -0700
@@ -2360,9 +2360,9 @@
 			lbmStartIO(bp);
 			spin_lock_irq(&log_redrive_lock);
 		}
-		if (freezing(current)) {
+		if (todo_list_active()) {
 			spin_unlock_irq(&log_redrive_lock);
-			refrigerator();
+			run_todo_list();
 		} else {
 			add_wait_queue(&jfs_IO_thread_wait, &wq);
 			set_current_state(TASK_INTERRUPTIBLE);
Index: linux-2.6.13-rc3-mm3/fs/lockd/clntproc.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/fs/lockd/clntproc.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/fs/lockd/clntproc.c	2005-07-29 12:38:03.000000000 -0700
@@ -313,7 +313,7 @@
 	prepare_to_wait(queue, &wait, TASK_INTERRUPTIBLE);
 	if (!signalled ()) {
 		schedule_timeout(NLMCLNT_GRACE_WAIT);
-		try_to_freeze();
+		try_todo_list();
 		if (!signalled ())
 			status = 0;
 	}
Index: linux-2.6.13-rc3-mm3/fs/xfs/linux-2.6/xfs_buf.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/fs/xfs/linux-2.6/xfs_buf.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/fs/xfs/linux-2.6/xfs_buf.c	2005-07-29 12:38:03.000000000 -0700
@@ -1771,9 +1771,9 @@
 
 	INIT_LIST_HEAD(&tmp);
 	do {
-		if (unlikely(freezing(current))) {
+		if (unlikely(todo_list_active())) {
 			xfsbufd_force_sleep = 1;
-			refrigerator();
+			run_todo_list();
 		} else {
 			xfsbufd_force_sleep = 0;
 		}
Index: linux-2.6.13-rc3-mm3/fs/xfs/linux-2.6/xfs_super.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/fs/xfs/linux-2.6/xfs_super.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/fs/xfs/linux-2.6/xfs_super.c	2005-07-29 12:38:03.000000000 -0700
@@ -482,8 +482,8 @@
 	for (;;) {
 		set_current_state(TASK_INTERRUPTIBLE);
 		timeleft = schedule_timeout(timeleft);
-		/* swsusp */
-		try_to_freeze();
+
+		try_todo_list();
 		if (vfsp->vfs_flag & VFS_UMOUNT)
 			break;
 
Index: linux-2.6.13-rc3-mm3/kernel/sched.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/kernel/sched.c	2005-07-29 12:32:23.000000000 -0700
+++ linux-2.6.13-rc3-mm3/kernel/sched.c	2005-07-29 12:38:03.000000000 -0700
@@ -4524,7 +4524,7 @@
 		struct list_head *head;
 		migration_req_t *req;
 
-		try_to_freeze();
+		try_todo_list();
 
 		spin_lock_irq(&rq->lock);
 
Index: linux-2.6.13-rc3-mm3/mm/pdflush.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/mm/pdflush.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/mm/pdflush.c	2005-07-29 12:38:03.000000000 -0700
@@ -105,7 +105,7 @@
 		spin_unlock_irq(&pdflush_lock);
 
 		schedule();
-		if (try_to_freeze()) {
+		if (try_todo_list()) {
 			spin_lock_irq(&pdflush_lock);
 			continue;
 		}
Index: linux-2.6.13-rc3-mm3/mm/vmscan.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/mm/vmscan.c	2005-07-29 12:32:18.000000000 -0700
+++ linux-2.6.13-rc3-mm3/mm/vmscan.c	2005-07-29 12:38:03.000000000 -0700
@@ -1222,7 +1222,7 @@
 	for ( ; ; ) {
 		unsigned long new_order;
 
-		try_to_freeze();
+		try_todo_list();
 
 		prepare_to_wait(&pgdat->kswapd_wait, &wait, TASK_INTERRUPTIBLE);
 		new_order = pgdat->kswapd_max_order;
Index: linux-2.6.13-rc3-mm3/net/rxrpc/krxiod.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/net/rxrpc/krxiod.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/net/rxrpc/krxiod.c	2005-07-29 12:38:03.000000000 -0700
@@ -138,7 +138,7 @@
 
 		_debug("### End Work");
 
-		try_to_freeze();
+		try_todo_list();
 
                 /* discard pending signals */
 		rxrpc_discard_my_signals();
Index: linux-2.6.13-rc3-mm3/net/rxrpc/krxtimod.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/net/rxrpc/krxtimod.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/net/rxrpc/krxtimod.c	2005-07-29 12:38:03.000000000 -0700
@@ -90,7 +90,7 @@
 			complete_and_exit(&krxtimod_dead, 0);
 		}
 
-		try_to_freeze();
+		try_todo_list();
 
 		/* discard pending signals */
 		rxrpc_discard_my_signals();
Index: linux-2.6.13-rc3-mm3/net/sunrpc/svcsock.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/net/sunrpc/svcsock.c	2005-07-12 21:46:46.000000000 -0700
+++ linux-2.6.13-rc3-mm3/net/sunrpc/svcsock.c	2005-07-29 12:38:03.000000000 -0700
@@ -1186,7 +1186,7 @@
 	arg->len = (pages-1)*PAGE_SIZE;
 	arg->tail[0].iov_len = 0;
 
-	try_to_freeze();
+	try_todo_list();
 	if (signalled())
 		return -EINTR;
 
@@ -1227,7 +1227,7 @@
 
 		schedule_timeout(timeout);
 
-		try_to_freeze();
+		try_todo_list();
 
 		spin_lock_bh(&serv->sv_lock);
 		remove_wait_queue(&rqstp->rq_wait, &wait);
Index: linux-2.6.13-rc3-mm3/drivers/net/8139too.c
===================================================================
--- linux-2.6.13-rc3-mm3.orig/drivers/net/8139too.c	2005-07-29 12:32:00.000000000 -0700
+++ linux-2.6.13-rc3-mm3/drivers/net/8139too.c	2005-07-29 12:38:03.000000000 -0700
@@ -1605,8 +1605,7 @@
 		timeout = next_tick;
 		do {
 			timeout = interruptible_sleep_on_timeout (&tp->thr_wait, timeout);
-			/* make swsusp happy with our thread */
-			try_to_freeze();
+			try_todo_list();
 		} while (!signal_pending (current) && (timeout > 0));
 
 		if (signal_pending (current)) {

Re: [PATCH 2/4] Task notifier against mm: Implement todo list in task_struct

[Pavel Machek]

Hi!

> Introduce a todo notifier in the task_struct so that a task can be told to do
> certain things. Abuse the suspend hooks try_to_freeze, freezing and refrigerator
> to establish checkpoints where the todo list is processed. This will break software
> suspend (next patch fixes and cleans up software suspend).

VERSION = 2
PATCHLEVEL = 6
SUBLEVEL = 13
EXTRAVERSION =-rc3-mm3

This patch fails:

pavel@amd:/usr/src/linux-mm$ cat /tmp/delme | patch -Esp1
1 out of 3 hunks FAILED -- saving rejects to file include/linux/sched.h.rej
pavel@amd:/usr/src/linux-mm$

No wonder when -mm already contains:

/*
 * Check if there is a request to freeze a process
 */
static inline int freezing(struct task_struct *p)
{
        return test_ti_thread_flag(p->thread_info, TIF_FREEZE);
}
	
									Pavel

-- 
teflon -- maybe it is a trademark, but it should not be.

Re: [PATCH 2/4] Task notifier against mm: Implement todo list in task_struct

[Pavel Machek]

Hi!

> > Introduce a todo notifier in the task_struct so that a task can be told to do
> > certain things. Abuse the suspend hooks try_to_freeze, freezing and refrigerator
> > to establish checkpoints where the todo list is processed. This will break software
> > suspend (next patch fixes and cleans up software suspend).
> 
> VERSION = 2
> PATCHLEVEL = 6
> SUBLEVEL = 13
> EXTRAVERSION =-rc3-mm3
> 
> This patch fails:
> 
> pavel@amd:/usr/src/linux-mm$ cat /tmp/delme | patch -Esp1
> 1 out of 3 hunks FAILED -- saving rejects to file include/linux/sched.h.rej
> pavel@amd:/usr/src/linux-mm$

(Notice that I do not nice 4 patches with changelogs. One patch
against known-good version should be enough for testing.)
								Pavel
-- 
teflon -- maybe it is a trademark, but it should not be.

Re: [PATCH 2/4] Task notifier against mm: Implement todo list in task_struct

[Christoph Lameter]

On Sat, 30 Jul 2005, Pavel Machek wrote:

> No wonder when -mm already contains:
> 
> /*
>  * Check if there is a request to freeze a process
>  */
> static inline int freezing(struct task_struct *p)
> {
>         return test_ti_thread_flag(p->thread_info, TIF_FREEZE);
> }

Yes I told you to remove the TIF_FREEZE patch.

Re: [PATCH 2/4] Task notifier against mm: Implement todo list in task_struct

[Pavel Machek]

Hi!

> > /*
> >  * Check if there is a request to freeze a process
> >  */
> > static inline int freezing(struct task_struct *p)
> > {
> >         return test_ti_thread_flag(p->thread_info, TIF_FREEZE);
> > }
> 
> Yes I told you to remove the TIF_FREEZE patch.

Okay, I took 2.6.13-rc3-mm3, removed TIF_FREEZE patch, and applied
your series. (This time it applied cleanly). After first suspend
machine locked hard at time it should switch back to original
console. On the next try, it appeared to lock up, but then I somehow
managed to switch consoles... unfortunately it was locked up hard at
that point, too.
								Pavel
-- 
if you have sharp zaurus hardware you don't need... you know my address

Re: [PATCH 2/4] Task notifier against mm: Implement todo list in task_struct

[Christoph Lameter]

On Sat, 30 Jul 2005, Pavel Machek wrote:

> > Yes I told you to remove the TIF_FREEZE patch.
> 
> Okay, I took 2.6.13-rc3-mm3, removed TIF_FREEZE patch, and applied
> your series. (This time it applied cleanly). After first suspend
> machine locked hard at time it should switch back to original
> console. On the next try, it appeared to lock up, but then I somehow
> managed to switch consoles... unfortunately it was locked up hard at
> that point, too.

Hmmm. I have only run suspend / resume in text mode so far. Switched back 
to original console means that you ran X right?

Re: [PATCH 2/4] Task notifier against mm: Implement todo list in task_struct

[Pavel Machek]

Hi!

> > > Yes I told you to remove the TIF_FREEZE patch.
> > 
> > Okay, I took 2.6.13-rc3-mm3, removed TIF_FREEZE patch, and applied
> > your series. (This time it applied cleanly). After first suspend
> > machine locked hard at time it should switch back to original
> > console. On the next try, it appeared to lock up, but then I somehow
> > managed to switch consoles... unfortunately it was locked up hard at
> > that point, too.
> 
> Hmmm. I have only run suspend / resume in text mode so far. Switched back 
> to original console means that you ran X right?

No, I was running text consoles. vesafb in this case.

								Pavel
-- 
if you have sharp zaurus hardware you don't need... you know my address

Re: [PATCH 2/4] Task notifier against mm: Implement todo list in task_struct

[Christoph Lameter]

Got a new suspend patchsset at 

ftp://ftp.kernel.org:/pub/linux/kernel/people/christoph/suspend/2.6.13-rc4-mm1

Check the series file for the sequence of patches.

Re: [PATCH 2/4] Task notifier against mm: Implement todo list in task_struct

[Pavel Machek]

Hi!

> Got a new suspend patchsset at 
> 
> ftp://ftp.kernel.org:/pub/linux/kernel/people/christoph/suspend/2.6.13-rc4-mm1
> 
> Check the series file for the sequence of patches.

Something still goes very wrong after first resume. It seems to work
ok for few seconds, then console switch takes 10 seconds to react and
cursor stops blinking, and then it is dead.
								Pavel
-- 
if you have sharp zaurus hardware you don't need... you know my address

Re: [PATCH 2/4] Task notifier against mm: Implement todo list in task_struct

[Christoph Lameter]

On Mon, 8 Aug 2005, Pavel Machek wrote:

> Hi!
> 
> > Got a new suspend patchsset at 
> > 
> > ftp://ftp.kernel.org:/pub/linux/kernel/people/christoph/suspend/2.6.13-rc4-mm1
> > 
> > Check the series file for the sequence of patches.
> 
> Something still goes very wrong after first resume. It seems to work
> ok for few seconds, then console switch takes 10 seconds to react and
> cursor stops blinking, and then it is dead.

Could you get me some more details as to what is happening?

This means it:

1. suspends correctly.

2. resumes.

3. Then after 10 seconds there is a crash?

Re: [PATCH 2/4] Task notifier against mm: Implement todo list in task_struct

[Pavel Machek]

Hi!

> > > Got a new suspend patchsset at 
> > > 
> > > ftp://ftp.kernel.org:/pub/linux/kernel/people/christoph/suspend/2.6.13-rc4-mm1
> > > 
> > > Check the series file for the sequence of patches.
> > 
> > Something still goes very wrong after first resume. It seems to work
> > ok for few seconds, then console switch takes 10 seconds to react and
> > cursor stops blinking, and then it is dead.
> 
> Could you get me some more details as to what is happening?
> 
> This means it:
> 
> 1. suspends correctly.
> 
> 2. resumes.
> 
> 3. Then after 10 seconds there is a crash?

More or less. It was more like:

then after 10 seconds machine freezes. You press Alt-F1 to switch
consoles, nothing happens for 3 seconds, then it switches. [Seems like
some problems with console kernel thread to me... Using vesafb and
acpi.]
								Pavel
-- 
if you have sharp zaurus hardware you don't need... you know my address