PERFORCE change 100707 for review

[Paolo Pisati]

http://perforce.freebsd.org/chv.cgi?CH=100707

Change 100707 by piso at piso_newluxor on 2006/07/06 09:52:41

	Now we have a rwlock for the modules in kernel land (handler_rw) 
	and nothing in userland: to avoid races in userland the
	lock will go into *_dll(), but for now we can live without
	it cause libalias is used only in single threaded app.

Affected files ...

.. //depot/projects/soc2005/libalias/sys/netinet/libalias/alias_mod.c#11 edit
.. //depot/projects/soc2005/libalias/sys/netinet/libalias/alias_mod.h#11 edit

Differences ...

==== //depot/projects/soc2005/libalias/sys/netinet/libalias/alias_mod.c#11 (text+ko) ====

@@ -60,92 +60,96 @@
 #include <sys/types.h>
 
 /* protocol and userland module handlers chains */
-struct chain handler_chain;
+struct chain    handler_chain;
+#ifdef _KERNEL
+struct rwlock   handler_rw;
+#endif
+
 SLIST_HEAD(dll_chain, dll) dll_chain = SLIST_HEAD_INITIALIZER(foo); 
 
 #ifdef _KERNEL
 
-#define	LIBALIAS_LOCK_INIT(_chain) \
-        rw_init(&_chain->rw, "Libalias_rwlock")
-#define	LIBALIAS_LOCK_DESTROY(_chain)	rw_destroy(&_chain->rw)
-#define	LIBALIAS_WLOCK_ASSERT(_chain) \
-        rw_assert(&_chain->rw, RA_WLOCKED)
+#define	LIBALIAS_LOCK_INIT() \
+        rw_init(&handler_rw, "Libalias_modules_rwlock")
+#define	LIBALIAS_LOCK_DESTROY()	rw_destroy(&handler_rw)
+#define	LIBALIAS_WLOCK_ASSERT() \
+        rw_assert(&handler_rw, RA_WLOCKED)
 
 static __inline void
-LIBALIAS_RLOCK(struct chain *chain)
+LIBALIAS_RLOCK(void)
 {
-	rw_rlock(&chain->rw);
+	rw_rlock(&handler_rw);
 }
 
 static __inline void
-LIBALIAS_RUNLOCK(struct chain *chain)
+LIBALIAS_RUNLOCK(void)
 {
-	rw_runlock(&chain->rw);
+	rw_runlock(&handler_rw);
 }
 
 static __inline void
-LIBALIAS_WLOCK(struct chain *chain)
+LIBALIAS_WLOCK(void)
 {
-	rw_wlock(&chain->rw);
+	rw_wlock(&handler_rw);
 }
 
 static __inline void
-LIBALIAS_WUNLOCK(struct chain *chain)
+LIBALIAS_WUNLOCK(void)
 {
-	rw_wunlock(&chain->rw);
+	rw_wunlock(&handler_rw);
 }
 
 static void
-_handler_chain_init(struct chain *chain) {
+_handler_chain_init(void) {
 
-	if (!rw_initialized(&chain->rw))
-		LIBALIAS_LOCK_INIT(chain);
+	if (!rw_initialized(&handler_rw))
+		LIBALIAS_LOCK_INIT();
 }
 
 static void
-_handler_chain_destroy(struct chain *chain) {
+_handler_chain_destroy(void) {
 
-	if (rw_initialized(&chain->rw))
-		LIBALIAS_LOCK_DESTROY(chain);
+	if (rw_initialized(&handler_rw))
+		LIBALIAS_LOCK_DESTROY();
 }
 
 #else
 
-#define	LIBALIAS_LOCK_INIT(_chain) ;
-#define	LIBALIAS_LOCK_DESTROY(_chain)	;
-#define	LIBALIAS_WLOCK_ASSERT(_chain)	;
+#define	LIBALIAS_LOCK_INIT() ;
+#define	LIBALIAS_LOCK_DESTROY()	;
+#define	LIBALIAS_WLOCK_ASSERT()	;
 
 static __inline void
-LIBALIAS_RLOCK(struct chain *chain __unused)
+LIBALIAS_RLOCK(void)
 {
 	;
 }
 
 static __inline void
-LIBALIAS_RUNLOCK(struct chain *chain __unused)
+LIBALIAS_RUNLOCK(void)
 {
 	;
 }
 
 static __inline void
-LIBALIAS_WLOCK(struct chain *chain __unused)
+LIBALIAS_WLOCK(void)
 {
 	;
 }
 
 static __inline void
-LIBALIAS_WUNLOCK(struct chain *chain __unused)
+LIBALIAS_WUNLOCK(void)
 {
 	;
 }
 
 static void
-_handler_chain_init(struct chain *c __unused) {
+_handler_chain_init(void) {
 	;
 }
 
 static void
-_handler_chain_destroy(struct chain *c __unused) {
+_handler_chain_destroy(void) {
 	;
 }
 
@@ -153,12 +157,12 @@
 
 void
 handler_chain_init(void) {
-	_handler_chain_init(&handler_chain);
+	_handler_chain_init();
 }
 
 void
 handler_chain_destroy(void) {
-	_handler_chain_destroy(&handler_chain);
+	_handler_chain_destroy();
 }
 
 static int
@@ -166,7 +170,7 @@
 	struct proto_handler **b;
 	int i = 0;
 
-	LIBALIAS_WLOCK_ASSERT(c);	
+	LIBALIAS_WLOCK_ASSERT();	
 	b = (struct proto_handler **)&c->chain;
 	p->next = NULL; /* i'm paranoid... */
 	for(; *b != NULL; b = &((*b)->next), i++) {
@@ -186,7 +190,7 @@
 _detach_handler(struct chain *c, struct proto_handler *p) {
 	struct proto_handler **b;
 
-	LIBALIAS_WLOCK_ASSERT(c);	
+	LIBALIAS_WLOCK_ASSERT();	
 	b = (struct proto_handler **)&c->chain;
 	for(; (*b != NULL) && (*b != p); b = &((*b)->next))
 		;
@@ -199,13 +203,13 @@
 attach_handlers(struct proto_handler *_p) {
 	int i, res = NOK;
 
-	LIBALIAS_WLOCK(&handler_chain);
+	LIBALIAS_WLOCK();
 	for (i=0; 1; i++) {
 		if (*((int *)&_p[i]) == EOH) break;
 		res = _attach_handler(&handler_chain, &_p[i]);
 		if (res != OK) break;
 	}
-	LIBALIAS_WUNLOCK(&handler_chain);
+	LIBALIAS_WUNLOCK();
 	return (res);
 }
 
@@ -213,13 +217,13 @@
 detach_handlers(struct proto_handler *_p) {
 	int i, res = NOK;
 
-	LIBALIAS_WLOCK(&handler_chain);
+	LIBALIAS_WLOCK();
 	for (i=0; 1; i++) {
 		if (*((int *)&_p[i]) == EOH) break;
 		res = _detach_handler(&handler_chain, &_p[i]);
 		if (res != OK) break;
 	}
-	LIBALIAS_WUNLOCK(&handler_chain);
+	LIBALIAS_WUNLOCK();
 	return (res);
 }
 
@@ -227,9 +231,9 @@
 detach_handler(struct proto_handler *_p) {
 	int res = NOK;
 
-	LIBALIAS_WLOCK(&handler_chain);
+	LIBALIAS_WLOCK();
 	res = _detach_handler(&handler_chain, _p);
-	LIBALIAS_WUNLOCK(&handler_chain);
+	LIBALIAS_WUNLOCK();
 	return (res);
 }
 
@@ -238,14 +242,14 @@
 	struct proto_handler *p;
 	int err;
 
-	LIBALIAS_RLOCK(&handler_chain);
+	LIBALIAS_RLOCK();
 	for (p = handler_chain.chain, err = EHDNOF; p != NULL; p = p->next)
 		if ((p->dir & dir) && (p->proto & proto))
 			if (p->fingerprint(la, pip, ad) == OK) {
 				err = p->protohandler(la, pip, ad);
 				break;
 			}
-	LIBALIAS_RUNLOCK(&handler_chain);
+	LIBALIAS_RUNLOCK();
 	return (err);	
 }
 

==== //depot/projects/soc2005/libalias/sys/netinet/libalias/alias_mod.h#11 (text+ko) ====

@@ -32,10 +32,6 @@
 #ifndef _ALIAS_MOD_H_
 #define _ALIAS_MOD_H_
 
-#include <sys/param.h>
-#include <sys/lock.h>
-#include <sys/rwlock.h>
-
 /* Protocol handlers struct & function. */
 
 /* Packet flow direction. */
@@ -83,7 +79,6 @@
 // XXX - convert it to use queue(3)
 struct chain {
 	void            *chain;	
-	struct rwlock   rw;
 };
 
 /*