powerpc-OF-convert-to-raw-lock.patch

From 6612f21aa244a24ed3dc210b15d92fee5d1c98ad Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Wed, 29 Jul 2009 13:59:43 +0200
Subject: [PATCH] powerpc: OF convert to raw lock

commit 5b659531c96943c3eea21b3dbcb83e6320d0f46b in tip.

Replaced the RW lock for now with raw_spinlock. We have no
raw_rwlocks in -rt right now and I doubt that the OF path is
performance critical.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

diff --git a/drivers/of/base.c b/drivers/of/base.c
index cb96888..861c9d6 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -28,7 +28,7 @@ struct device_node *of_chosen;
 /* use when traversing tree through the allnext, child, sibling,
  * or parent members of struct device_node.
  */
-DEFINE_RWLOCK(devtree_lock);
+DEFINE_RAW_SPINLOCK(devtree_lock);
 
 int of_n_addr_cells(struct device_node *np)
 {
@@ -146,7 +146,7 @@ struct property *of_find_property(const struct device_node *np,
 	if (!np)
 		return NULL;
 
-	read_lock(&devtree_lock);
+	raw_spin_lock(&devtree_lock);
 	for (pp = np->properties; pp != 0; pp = pp->next) {
 		if (of_prop_cmp(pp->name, name) == 0) {
 			if (lenp != 0)
@@ -154,7 +154,7 @@ struct property *of_find_property(const struct device_node *np,
 			break;
 		}
 	}
-	read_unlock(&devtree_lock);
+	raw_spin_unlock(&devtree_lock);
 
 	return pp;
 }
@@ -172,13 +172,13 @@ struct device_node *of_find_all_nodes(struct device_node *prev)
 {
 	struct device_node *np;
 
-	read_lock(&devtree_lock);
+	raw_spin_lock(&devtree_lock);
 	np = prev ? prev->allnext : allnodes;
 	for (; np != NULL; np = np->allnext)
 		if (of_node_get(np))
 			break;
 	of_node_put(prev);
-	read_unlock(&devtree_lock);
+	raw_spin_unlock(&devtree_lock);
 	return np;
 }
 EXPORT_SYMBOL(of_find_all_nodes);
@@ -281,9 +281,9 @@ struct device_node *of_get_parent(const struct device_node *node)
 	if (!node)
 		return NULL;
 
-	read_lock(&devtree_lock);
+	raw_spin_lock(&devtree_lock);
 	np = of_node_get(node->parent);
-	read_unlock(&devtree_lock);
+	raw_spin_unlock(&devtree_lock);
 	return np;
 }
 EXPORT_SYMBOL(of_get_parent);
@@ -306,10 +306,10 @@ struct device_node *of_get_next_parent(struct device_node *node)
 	if (!node)
 		return NULL;
 
-	read_lock(&devtree_lock);
+	raw_spin_lock(&devtree_lock);
 	parent = of_node_get(node->parent);
 	of_node_put(node);
-	read_unlock(&devtree_lock);
+	raw_spin_unlock(&devtree_lock);
 	return parent;
 }
 
@@ -326,13 +326,13 @@ struct device_node *of_get_next_child(const struct device_node *node,
 {
 	struct device_node *next;
 
-	read_lock(&devtree_lock);
+	raw_spin_lock(&devtree_lock);
 	next = prev ? prev->sibling : node->child;
 	for (; next; next = next->sibling)
 		if (of_node_get(next))
 			break;
 	of_node_put(prev);
-	read_unlock(&devtree_lock);
+	raw_spin_unlock(&devtree_lock);
 	return next;
 }
 EXPORT_SYMBOL(of_get_next_child);
@@ -348,13 +348,13 @@ struct device_node *of_find_node_by_path(const char *path)
 {
 	struct device_node *np = allnodes;
 
-	read_lock(&devtree_lock);
+	raw_spin_lock(&devtree_lock);
 	for (; np; np = np->allnext) {
 		if (np->full_name && (of_node_cmp(np->full_name, path) == 0)
 		    && of_node_get(np))
 			break;
 	}
-	read_unlock(&devtree_lock);
+	raw_spin_unlock(&devtree_lock);
 	return np;
 }
 EXPORT_SYMBOL(of_find_node_by_path);
@@ -375,14 +375,14 @@ struct device_node *of_find_node_by_name(struct device_node *from,
 {
 	struct device_node *np;
 
-	read_lock(&devtree_lock);
+	raw_spin_lock(&devtree_lock);
 	np = from ? from->allnext : allnodes;
 	for (; np; np = np->allnext)
 		if (np->name && (of_node_cmp(np->name, name) == 0)
 		    && of_node_get(np))
 			break;
 	of_node_put(from);
-	read_unlock(&devtree_lock);
+	raw_spin_unlock(&devtree_lock);
 	return np;
 }
 EXPORT_SYMBOL(of_find_node_by_name);
@@ -404,14 +404,14 @@ struct device_node *of_find_node_by_type(struct device_node *from,
 {
 	struct device_node *np;
 
-	read_lock(&devtree_lock);
+	raw_spin_lock(&devtree_lock);
 	np = from ? from->allnext : allnodes;
 	for (; np; np = np->allnext)
 		if (np->type && (of_node_cmp(np->type, type) == 0)
 		    && of_node_get(np))
 			break;
 	of_node_put(from);
-	read_unlock(&devtree_lock);
+	raw_spin_unlock(&devtree_lock);
 	return np;
 }
 EXPORT_SYMBOL(of_find_node_by_type);
@@ -435,7 +435,7 @@ struct device_node *of_find_compatible_node(struct device_node *from,
 {
 	struct device_node *np;
 
-	read_lock(&devtree_lock);
+	raw_spin_lock(&devtree_lock);
 	np = from ? from->allnext : allnodes;
 	for (; np; np = np->allnext) {
 		if (type
@@ -445,7 +445,7 @@ struct device_node *of_find_compatible_node(struct device_node *from,
 			break;
 	}
 	of_node_put(from);
-	read_unlock(&devtree_lock);
+	raw_spin_unlock(&devtree_lock);
 	return np;
 }
 EXPORT_SYMBOL(of_find_compatible_node);
@@ -468,7 +468,7 @@ struct device_node *of_find_node_with_property(struct device_node *from,
 	struct device_node *np;
 	struct property *pp;
 
-	read_lock(&devtree_lock);
+	raw_spin_lock(&devtree_lock);
 	np = from ? from->allnext : allnodes;
 	for (; np; np = np->allnext) {
 		for (pp = np->properties; pp != 0; pp = pp->next) {
@@ -480,7 +480,7 @@ struct device_node *of_find_node_with_property(struct device_node *from,
 	}
 out:
 	of_node_put(from);
-	read_unlock(&devtree_lock);
+	raw_spin_unlock(&devtree_lock);
 	return np;
 }
 EXPORT_SYMBOL(of_find_node_with_property);
@@ -531,14 +531,14 @@ struct device_node *of_find_matching_node(struct device_node *from,
 {
 	struct device_node *np;
 
-	read_lock(&devtree_lock);
+	raw_spin_lock(&devtree_lock);
 	np = from ? from->allnext : allnodes;
 	for (; np; np = np->allnext) {
 		if (of_match_node(matches, np) && of_node_get(np))
 			break;
 	}
 	of_node_put(from);
-	read_unlock(&devtree_lock);
+	raw_spin_unlock(&devtree_lock);
 	return np;
 }
 EXPORT_SYMBOL(of_find_matching_node);
@@ -627,12 +627,12 @@ struct device_node *of_find_node_by_phandle(phandle handle)
 {
 	struct device_node *np;
 
-	read_lock(&devtree_lock);
+	raw_spin_lock(&devtree_lock);
 	for (np = allnodes; np; np = np->allnext)
 		if (np->phandle == handle)
 			break;
 	of_node_get(np);
-	read_unlock(&devtree_lock);
+	raw_spin_unlock(&devtree_lock);
 	return np;
 }
 EXPORT_SYMBOL(of_find_node_by_phandle);
@@ -787,18 +787,18 @@ int prom_add_property(struct device_node *np, struct property *prop)
 	unsigned long flags;
 
 	prop->next = NULL;
-	write_lock_irqsave(&devtree_lock, flags);
+	raw_spin_lock_irqsave(&devtree_lock, flags);
 	next = &np->properties;
 	while (*next) {
 		if (strcmp(prop->name, (*next)->name) == 0) {
 			/* duplicate ! don't insert it */
-			write_unlock_irqrestore(&devtree_lock, flags);
+			raw_spin_unlock_irqrestore(&devtree_lock, flags);
 			return -1;
 		}
 		next = &(*next)->next;
 	}
 	*next = prop;
-	write_unlock_irqrestore(&devtree_lock, flags);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
 
 #ifdef CONFIG_PROC_DEVICETREE
 	/* try to add to proc as well if it was initialized */
@@ -823,7 +823,7 @@ int prom_remove_property(struct device_node *np, struct property *prop)
 	unsigned long flags;
 	int found = 0;
 
-	write_lock_irqsave(&devtree_lock, flags);
+	raw_spin_lock_irqsave(&devtree_lock, flags);
 	next = &np->properties;
 	while (*next) {
 		if (*next == prop) {
@@ -836,7 +836,7 @@ int prom_remove_property(struct device_node *np, struct property *prop)
 		}
 		next = &(*next)->next;
 	}
-	write_unlock_irqrestore(&devtree_lock, flags);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
 
 	if (!found)
 		return -ENODEV;
@@ -866,7 +866,7 @@ int prom_update_property(struct device_node *np,
 	unsigned long flags;
 	int found = 0;
 
-	write_lock_irqsave(&devtree_lock, flags);
+	raw_spin_lock_irqsave(&devtree_lock, flags);
 	next = &np->properties;
 	while (*next) {
 		if (*next == oldprop) {
@@ -880,7 +880,7 @@ int prom_update_property(struct device_node *np,
 		}
 		next = &(*next)->next;
 	}
-	write_unlock_irqrestore(&devtree_lock, flags);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
 
 	if (!found)
 		return -ENODEV;
@@ -910,12 +910,12 @@ void of_attach_node(struct device_node *np)
 {
 	unsigned long flags;
 
-	write_lock_irqsave(&devtree_lock, flags);
+	raw_spin_lock_irqsave(&devtree_lock, flags);
 	np->sibling = np->parent->child;
 	np->allnext = allnodes;
 	np->parent->child = np;
 	allnodes = np;
-	write_unlock_irqrestore(&devtree_lock, flags);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
 }
 
 /**
@@ -929,7 +929,7 @@ void of_detach_node(struct device_node *np)
 	struct device_node *parent;
 	unsigned long flags;
 
-	write_lock_irqsave(&devtree_lock, flags);
+	raw_spin_lock_irqsave(&devtree_lock, flags);
 
 	parent = np->parent;
 	if (!parent)
@@ -960,7 +960,7 @@ void of_detach_node(struct device_node *np)
 	of_node_set_flag(np, OF_DETACHED);
 
 out_unlock:
-	write_unlock_irqrestore(&devtree_lock, flags);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
 }
 #endif /* defined(CONFIG_OF_DYNAMIC) */
 
diff --git a/include/linux/of.h b/include/linux/of.h
index f6d9cbc..d8869f7 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -68,7 +68,7 @@ struct device_node {
 /* Pointer for first entry in chain of all nodes. */
 extern struct device_node *allnodes;
 extern struct device_node *of_chosen;
-extern rwlock_t devtree_lock;
+extern raw_spinlock_t devtree_lock;
 
 static inline int of_node_check_flag(struct device_node *n, unsigned long flag)
 {
-- 
1.7.1.1