Linux-libre 4.1.5-gnupck-4.1.5-gnu

3 files changed, 62 insertions, 47 deletions

diff --git a/kernel/irq/resend.c b/kernel/irq/resend.c
index 9065107f0..7a5237a1b 100644
--- a/kernel/irq/resend.c
+++ b/kernel/irq/resend.c
@@ -75,13 +75,21 @@ void check_irq_resend(struct irq_desc *desc, unsigned int irq)
 		    !desc->irq_data.chip->irq_retrigger(&desc->irq_data)) {
 #ifdef CONFIG_HARDIRQS_SW_RESEND
 			/*
-			 * If the interrupt has a parent irq and runs
-			 * in the thread context of the parent irq,
-			 * retrigger the parent.
+			 * If the interrupt is running in the thread
+			 * context of the parent irq we need to be
+			 * careful, because we cannot trigger it
+			 * directly.
 			 */
-			if (desc->parent_irq &&
-			    irq_settings_is_nested_thread(desc))
+			if (irq_settings_is_nested_thread(desc)) {
+				/*
+				 * If the parent_irq is valid, we
+				 * retrigger the parent, otherwise we
+				 * do nothing.
+				 */
+				if (!desc->parent_irq)
+					return;
 				irq = desc->parent_irq;
+			}
 			/* Set it pending and activate the softirq: */
 			set_bit(irq, irqs_resend);
 			tasklet_schedule(&resend_tasklet);
diff --git a/kernel/sched/bfs.c b/kernel/sched/bfs.c
index a6d06efc1..5366182bd 100644
--- a/kernel/sched/bfs.c
+++ b/kernel/sched/bfs.c
@@ -134,7 +134,7 @@
 
 void print_scheduler_version(void)
 {
-	printk(KERN_INFO "BFS CPU scheduler v0.463 by Con Kolivas.\n");
+	printk(KERN_INFO "BFS CPU scheduler v0.464 by Con Kolivas.\n");
 }
 
 /*
@@ -986,13 +986,6 @@ static inline void deactivate_task(struct task_struct *p, struct rq *rq)
 	clear_sticky(p);
 }
 
-static ATOMIC_NOTIFIER_HEAD(task_migration_notifier);
-
-void register_task_migration_notifier(struct notifier_block *n)
-{
-	atomic_notifier_chain_register(&task_migration_notifier, n);
-}
-
 #ifdef CONFIG_SMP
 void set_task_cpu(struct task_struct *p, unsigned int cpu)
 {
@@ -3376,10 +3369,12 @@ static void __sched __schedule(void)
 {
 	struct task_struct *prev, *next, *idle;
 	unsigned long *switch_count;
-	bool deactivate = false;
+	bool deactivate;
 	struct rq *rq;
 	int cpu;
 
+need_resched:
+	deactivate = false;
 	preempt_disable();
 	cpu = smp_processor_id();
 	rq = cpu_rq(cpu);
@@ -3426,6 +3421,17 @@ static void __sched __schedule(void)
 		switch_count = &prev->nvcsw;
 	}
 
+	/*
+	 * If we are going to sleep and we have plugged IO queued, make
+	 * sure to submit it to avoid deadlocks.
+	 */
+	if (unlikely(deactivate && blk_needs_flush_plug(prev))) {
+		grq_unlock_irq();
+		preempt_enable_no_resched();
+		blk_schedule_flush_plug(prev);
+		goto need_resched;
+	}
+
 	update_clocks(rq);
 	update_cpu_clock_switch(rq, prev);
 	if (rq->clock - rq->last_tick > HALF_JIFFY_NS)
@@ -3516,23 +3522,8 @@ rerun_prev_unlocked:
 	sched_preempt_enable_no_resched();
 }
 
-static inline void sched_submit_work(struct task_struct *tsk)
-{
-	if (!tsk->state || tsk_is_pi_blocked(tsk))
-		return;
-	/*
-	 * If we are going to sleep and we have plugged IO queued,
-	 * make sure to submit it to avoid deadlocks.
-	 */
-	if (blk_needs_flush_plug(tsk))
-		blk_schedule_flush_plug(tsk);
-}
-
 asmlinkage __visible void __sched schedule(void)
 {
-	struct task_struct *tsk = current;
-
-	sched_submit_work(tsk);
 	do {
 		__schedule();
 	} while (need_resched());
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 02bece4a9..eb11011b5 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -98,6 +98,13 @@ struct ftrace_pid {
 	struct pid *pid;
 };
 
+static bool ftrace_pids_enabled(void)
+{
+	return !list_empty(&ftrace_pids);
+}
+
+static void ftrace_update_trampoline(struct ftrace_ops *ops);
+
 /*
  * ftrace_disabled is set when an anomaly is discovered.
  * ftrace_disabled is much stronger than ftrace_enabled.
@@ -109,7 +116,6 @@ static DEFINE_MUTEX(ftrace_lock);
 static struct ftrace_ops *ftrace_control_list __read_mostly = &ftrace_list_end;
 static struct ftrace_ops *ftrace_ops_list __read_mostly = &ftrace_list_end;
 ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub;
-ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub;
 static struct ftrace_ops global_ops;
 static struct ftrace_ops control_ops;
 
@@ -183,14 +189,7 @@ static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip,
 	if (!test_tsk_trace_trace(current))
 		return;
 
-	ftrace_pid_function(ip, parent_ip, op, regs);
-}
-
-static void set_ftrace_pid_function(ftrace_func_t func)
-{
-	/* do not set ftrace_pid_function to itself! */
-	if (func != ftrace_pid_func)
-		ftrace_pid_function = func;
+	op->saved_func(ip, parent_ip, op, regs);
 }
 
 /**
@@ -202,7 +201,6 @@ static void set_ftrace_pid_function(ftrace_func_t func)
 void clear_ftrace_function(void)
 {
 	ftrace_trace_function = ftrace_stub;
-	ftrace_pid_function = ftrace_stub;
 }
 
 static void control_ops_disable_all(struct ftrace_ops *ops)
@@ -436,6 +434,12 @@ static int __register_ftrace_function(struct ftrace_ops *ops)
 	} else
 		add_ftrace_ops(&ftrace_ops_list, ops);
 
+	/* Always save the function, and reset at unregistering */
+	ops->saved_func = ops->func;
+
+	if (ops->flags & FTRACE_OPS_FL_PID && ftrace_pids_enabled())
+		ops->func = ftrace_pid_func;
+
 	ftrace_update_trampoline(ops);
 
 	if (ftrace_enabled)
@@ -463,15 +467,28 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops)
 	if (ftrace_enabled)
 		update_ftrace_function();
 
+	ops->func = ops->saved_func;
+
 	return 0;
 }
 
 static void ftrace_update_pid_func(void)
 {
+	bool enabled = ftrace_pids_enabled();
+	struct ftrace_ops *op;
+
 	/* Only do something if we are tracing something */
 	if (ftrace_trace_function == ftrace_stub)
 		return;
 
+	do_for_each_ftrace_op(op, ftrace_ops_list) {
+		if (op->flags & FTRACE_OPS_FL_PID) {
+			op->func = enabled ? ftrace_pid_func :
+				op->saved_func;
+			ftrace_update_trampoline(op);
+		}
+	} while_for_each_ftrace_op(op);
+
 	update_ftrace_function();
 }
 
@@ -1133,7 +1150,8 @@ static struct ftrace_ops global_ops = {
 	.local_hash.filter_hash		= EMPTY_HASH,
 	INIT_OPS_HASH(global_ops)
 	.flags				= FTRACE_OPS_FL_RECURSION_SAFE |
-					  FTRACE_OPS_FL_INITIALIZED,
+					  FTRACE_OPS_FL_INITIALIZED |
+					  FTRACE_OPS_FL_PID,
 };
 
 /*
@@ -5023,7 +5041,9 @@ static void ftrace_update_trampoline(struct ftrace_ops *ops)
 
 static struct ftrace_ops global_ops = {
 	.func			= ftrace_stub,
-	.flags			= FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED,
+	.flags			= FTRACE_OPS_FL_RECURSION_SAFE |
+				  FTRACE_OPS_FL_INITIALIZED |
+				  FTRACE_OPS_FL_PID,
 };
 
 static int __init ftrace_nodyn_init(void)
@@ -5080,11 +5100,6 @@ void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func)
 		if (WARN_ON(tr->ops->func != ftrace_stub))
 			printk("ftrace ops had %pS for function\n",
 			       tr->ops->func);
-		/* Only the top level instance does pid tracing */
-		if (!list_empty(&ftrace_pids)) {
-			set_ftrace_pid_function(func);
-			func = ftrace_pid_func;
-		}
 	}
 	tr->ops->func = func;
 	tr->ops->private = tr;
@@ -5371,7 +5386,7 @@ static void *fpid_start(struct seq_file *m, loff_t *pos)
 {
 	mutex_lock(&ftrace_lock);
 
-	if (list_empty(&ftrace_pids) && (!*pos))
+	if (!ftrace_pids_enabled() && (!*pos))
 		return (void *) 1;
 
 	return seq_list_start(&ftrace_pids, *pos);
@@ -5610,6 +5625,7 @@ static struct ftrace_ops graph_ops = {
 	.func			= ftrace_stub,
 	.flags			= FTRACE_OPS_FL_RECURSION_SAFE |
 				   FTRACE_OPS_FL_INITIALIZED |
+				   FTRACE_OPS_FL_PID |
 				   FTRACE_OPS_FL_STUB,
 #ifdef FTRACE_GRAPH_TRAMP_ADDR
 	.trampoline		= FTRACE_GRAPH_TRAMP_ADDR,