[master] d0db0a5 Get rid of the LRU list sentenniel.

[Poul-Henning Kamp]

commit d0db0a59a90d54417ea00ccb4279d3f65c4c2ba4
Author: Poul-Henning Kamp <phk at FreeBSD.org>
Date:   Wed Feb 9 10:12:44 2011 +0000

    Get rid of the LRU list sentenniel.

diff --git a/bin/varnishd/cache.h b/bin/varnishd/cache.h
index da5c80e..08d10ec 100644
--- a/bin/varnishd/cache.h
+++ b/bin/varnishd/cache.h
@@ -382,7 +382,7 @@ struct objcore {
 #define OC_F_PRIV		(1<<5)		/* Stevedore private flag */
 	unsigned		timer_idx;
 	VTAILQ_ENTRY(objcore)	list;
-	VLIST_ENTRY(objcore)	lru_list;
+	VTAILQ_ENTRY(objcore)	lru_list;
 	VTAILQ_ENTRY(objcore)	ban_list;
 	struct ban		*ban;
 };
@@ -416,15 +416,6 @@ oc_getlru(const struct objcore *oc)
 	return (oc->methods->getlru(oc));
 }
 
-/*--------------------------------------------------------------------*/
-
-struct lru {
-	unsigned		magic;
-#define LRU_MAGIC		0x3fec7bb0
-	VLIST_HEAD(,objcore)	lru_head;
-	struct objcore		senteniel;
-};
-
 /* Object structure --------------------------------------------------*/
 VTAILQ_HEAD(storagehead, storage);
 
@@ -634,7 +625,7 @@ void EXP_Inject(struct objcore *oc, struct lru *lru, double when);
 void EXP_Init(void);
 void EXP_Rearm(const struct object *o);
 void EXP_Touch(struct object *o, double tnow);
-int EXP_NukeOne(const struct sess *sp, const struct lru *lru);
+int EXP_NukeOne(const struct sess *sp, struct lru *lru);
 
 /* cache_fetch.c */
 struct storage *FetchStorage(const struct sess *sp, ssize_t sz);
diff --git a/bin/varnishd/cache_expire.c b/bin/varnishd/cache_expire.c
index 23c9cc2..0d3b1a2 100644
--- a/bin/varnishd/cache_expire.c
+++ b/bin/varnishd/cache_expire.c
@@ -98,7 +98,7 @@ exp_insert(struct objcore *oc, struct lru *lru)
 	assert(oc->timer_idx == BINHEAP_NOIDX);
 	binheap_insert(exp_heap, oc);
 	assert(oc->timer_idx != BINHEAP_NOIDX);
-	VLIST_INSERT_BEFORE(&lru->senteniel, oc, lru_list);
+	VTAILQ_INSERT_TAIL(&lru->lru_head, oc, lru_list);
 	oc->flags |= OC_F_ONLRU;
 }
 
@@ -187,8 +187,8 @@ EXP_Touch(struct object *o, double tnow)
 		return;
 
 	if (oc->flags & OC_F_ONLRU) {	/* XXX ?? */
-		VLIST_REMOVE(oc, lru_list);
-		VLIST_INSERT_BEFORE(&lru->senteniel, oc, lru_list);
+		VTAILQ_REMOVE(&lru->lru_head, oc, lru_list);
+		VTAILQ_INSERT_TAIL(&lru->lru_head, oc, lru_list);
 		VSC_main->n_lru_moved++;
 		o->last_lru = tnow;
 	}
@@ -239,6 +239,7 @@ static void * __match_proto__(void *start_routine(void *))
 exp_timer(struct sess *sp, void *priv)
 {
 	struct objcore *oc;
+	struct lru *lru;
 	double t;
 
 	(void)priv;
@@ -272,7 +273,8 @@ exp_timer(struct sess *sp, void *priv)
 
 		/* And from LRU */
 		if (oc->flags & OC_F_ONLRU) {
-			VLIST_REMOVE(oc, lru_list);
+			lru = oc_getlru(oc);
+			VTAILQ_REMOVE(&lru->lru_head, oc, lru_list);
 			oc->flags &= ~OC_F_ONLRU;
 		}
 
@@ -293,19 +295,14 @@ exp_timer(struct sess *sp, void *priv)
  */
 
 int
-EXP_NukeOne(const struct sess *sp, const struct lru *lru)
+EXP_NukeOne(const struct sess *sp, struct lru *lru)
 {
 	struct objcore *oc;
 	struct object *o;
 
 	/* Find the first currently unused object on the LRU.  */
 	Lck_Lock(&exp_mtx);
-	VLIST_FOREACH(oc, &lru->lru_head, lru_list) {
-		if (oc == &lru->senteniel) {
-			AZ(VLIST_NEXT(oc, lru_list));
-			oc = NULL;
-			break;
-		}
+	VTAILQ_FOREACH(oc, &lru->lru_head, lru_list) {
 		CHECK_OBJ_NOTNULL(oc, OBJCORE_MAGIC);
 		if (oc->timer_idx == BINHEAP_NOIDX)	/* exp_timer has it */
 			continue;
@@ -313,7 +310,7 @@ EXP_NukeOne(const struct sess *sp, const struct lru *lru)
 			break;
 	}
 	if (oc != NULL) {
-		VLIST_REMOVE(oc, lru_list);
+		VTAILQ_REMOVE(&lru->lru_head, oc, lru_list);
 		oc->flags &= ~OC_F_ONLRU;
 		binheap_delete(exp_heap, oc->timer_idx);
 		assert(oc->timer_idx == BINHEAP_NOIDX);
diff --git a/bin/varnishd/stevedore.c b/bin/varnishd/stevedore.c
index ae0e634..4865eaf 100644
--- a/bin/varnishd/stevedore.c
+++ b/bin/varnishd/stevedore.c
@@ -70,8 +70,7 @@ LRU_Alloc(void)
 
 	ALLOC_OBJ(l, LRU_MAGIC);
 	AN(l);
-	VLIST_INIT(&l->lru_head);
-	VLIST_INSERT_HEAD(&l->lru_head, &l->senteniel, lru_list);
+	VTAILQ_INIT(&l->lru_head);
 	return (l);
 }
 
diff --git a/bin/varnishd/stevedore.h b/bin/varnishd/stevedore.h
index 86da7ee..94a0e06 100644
--- a/bin/varnishd/stevedore.h
+++ b/bin/varnishd/stevedore.h
@@ -50,6 +50,16 @@ typedef void storage_close_f(const struct stevedore *);
 #include "vrt_stv_var.h"
 #undef VRTSTVTYPE
 
+/*--------------------------------------------------------------------*/
+
+struct lru {
+	unsigned		magic;
+#define LRU_MAGIC		0x3fec7bb0
+	VTAILQ_HEAD(,objcore)	lru_head;
+};
+
+/*--------------------------------------------------------------------*/
+
 struct stevedore {
 	unsigned		magic;
 #define STEVEDORE_MAGIC		0x4baf43db
diff --git a/bin/varnishd/storage_persistent.c b/bin/varnishd/storage_persistent.c
index 1c25e85..fa32472 100644
--- a/bin/varnishd/storage_persistent.c
+++ b/bin/varnishd/storage_persistent.c
@@ -601,10 +601,8 @@ debug_report_silo(struct cli *cli, const struct smp_sc *sc, int objs)
 		cli_out(cli, "    %u nobj, %u alloc, %u lobjlist, %u fixed\n",
 		    sg->nobj, sg->nalloc, sg->p.lobjlist, sg->nfixed);
 		if (objs) {
-			VLIST_FOREACH(oc, &sg->lru->lru_head, lru_list)
-				cli_out(cli, "      %s %p\n",
-				    oc == &sg->lru->senteniel ?
-				    "senteniel" : "OC: ", oc);
+			VTAILQ_FOREACH(oc, &sg->lru->lru_head, lru_list)
+				cli_out(cli, "      OC %p\n", oc);
 		}
 	}
 }