uipc: create dedicated lists for fast and slow timeout callbacks

This avoids having to walk all possible protocols only to check if they
have one (vast majority does not).

Original patch by kevans@.

Reviewed by:	kevans
Sponsored by:	Rubicon Communications, LLC ("Netgate")

2 files changed, 46 insertions, 17 deletions

diff --git a/sys/kern/uipc_domain.c b/sys/kern/uipc_domain.c
index b6aefec9556a..0946a2a75326 100644
--- a/sys/kern/uipc_domain.c
+++ b/sys/kern/uipc_domain.c
@@ -44,6 +44,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/kernel.h>
 #include <sys/lock.h>
 #include <sys/mutex.h>
+#include <sys/rmlock.h>
 #include <sys/socketvar.h>
 #include <sys/systm.h>
 
@@ -76,6 +77,14 @@ static struct callout pfslow_callout;
 static void	pffasttimo(void *);
 static void	pfslowtimo(void *);
 
+static struct rmlock pftimo_lock;
+RM_SYSINIT(pftimo_lock, &pftimo_lock, "pftimo");
+
+static LIST_HEAD(, protosw) pffast_list =
+    LIST_HEAD_INITIALIZER(pffast_list);
+static LIST_HEAD(, protosw) pfslow_list =
+    LIST_HEAD_INITIALIZER(pfslow_list);
+
 struct domain *domains;		/* registered protocol domains */
 int domain_init_status = 0;
 static struct mtx dom_mtx;		/* domain list lock */
@@ -183,8 +192,16 @@ domain_init(void *arg)
 	    ("Premature initialization of domain in non-default vnet"));
 	if (dp->dom_init)
 		(*dp->dom_init)();
-	for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
+	for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) {
 		protosw_init(pr);
+		rm_wlock(&pftimo_lock);
+		if (pr->pr_fasttimo != NULL)
+			LIST_INSERT_HEAD(&pffast_list, pr, pr_fasttimos);
+		if (pr->pr_slowtimo != NULL)
+			LIST_INSERT_HEAD(&pfslow_list, pr, pr_slowtimos);
+		rm_wunlock(&pftimo_lock);
+	}
+
 	/*
 	 * update global information about maximums
 	 */
@@ -387,6 +404,13 @@ pf_proto_register(int family, struct protosw *npr)
 	/* Copy the new struct protosw over the spacer. */
 	bcopy(npr, fpr, sizeof(*fpr));
 
+	rm_wlock(&pftimo_lock);
+	if (fpr->pr_fasttimo != NULL)
+		LIST_INSERT_HEAD(&pffast_list, fpr, pr_fasttimos);
+	if (fpr->pr_slowtimo != NULL)
+		LIST_INSERT_HEAD(&pfslow_list, fpr, pr_slowtimos);
+	rm_wunlock(&pftimo_lock);
+
 	/* Job is done, no more protection required. */
 	mtx_unlock(&dom_mtx);
 
@@ -447,6 +471,13 @@ pf_proto_unregister(int family, int protocol, int type)
 		return (EPROTONOSUPPORT);
 	}
 
+	rm_wlock(&pftimo_lock);
+	if (dpr->pr_fasttimo != NULL)
+		LIST_REMOVE(dpr, pr_fasttimos);
+	if (dpr->pr_slowtimo != NULL)
+		LIST_REMOVE(dpr, pr_slowtimos);
+	rm_wunlock(&pftimo_lock);
+
 	/* De-orbit the protocol and make the slot available again. */
 	dpr->pr_type = 0;
 	dpr->pr_domain = dp;
@@ -483,39 +514,33 @@ pfctlinput(int cmd, struct sockaddr *sa)
 static void
 pfslowtimo(void *arg)
 {
+	struct rm_priotracker tracker;
 	struct epoch_tracker et;
-	struct domain *dp;
 	struct protosw *pr;
 
+	rm_rlock(&pftimo_lock, &tracker);
 	NET_EPOCH_ENTER(et);
-	for (dp = domains; dp; dp = dp->dom_next) {
-		if ((atomic_load_int(&dp->dom_flags) & DOMF_INITED) == 0)
-			continue;
-		atomic_thread_fence_acq();
-		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
-			if (pr->pr_slowtimo)
-				(*pr->pr_slowtimo)();
+	LIST_FOREACH(pr, &pfslow_list, pr_slowtimos) {
+		(*pr->pr_slowtimo)();
 	}
 	NET_EPOCH_EXIT(et);
+	rm_runlock(&pftimo_lock, &tracker);
 	callout_reset(&pfslow_callout, hz/2, pfslowtimo, NULL);
 }
 
 static void
 pffasttimo(void *arg)
 {
+	struct rm_priotracker tracker;
 	struct epoch_tracker et;
-	struct domain *dp;
 	struct protosw *pr;
 
+	rm_rlock(&pftimo_lock, &tracker);
 	NET_EPOCH_ENTER(et);
-	for (dp = domains; dp; dp = dp->dom_next) {
-		if ((atomic_load_int(&dp->dom_flags) & DOMF_INITED) == 0)
-			continue;
-		atomic_thread_fence_acq();
-		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
-			if (pr->pr_fasttimo)
-				(*pr->pr_fasttimo)();
+	LIST_FOREACH(pr, &pffast_list, pr_fasttimos) {
+		(*pr->pr_fasttimo)();
 	}
 	NET_EPOCH_EXIT(et);
+	rm_runlock(&pftimo_lock, &tracker);
 	callout_reset(&pffast_callout, hz/5, pffasttimo, NULL);
 }
diff --git a/sys/sys/protosw.h b/sys/sys/protosw.h
index 5c2fa2d4077e..a929544501f4 100644
--- a/sys/sys/protosw.h
+++ b/sys/sys/protosw.h
@@ -35,6 +35,8 @@
 #ifndef _SYS_PROTOSW_H_
 #define _SYS_PROTOSW_H_
 
+#include <sys/queue.h>
+
 /* Forward declare these structures referenced from prototypes below. */
 struct kaiocb;
 struct mbuf;
@@ -93,6 +95,8 @@ struct protosw {
 	pr_drain_t *pr_drain;		/* flush any excess space possible */
 
 	struct	pr_usrreqs *pr_usrreqs;	/* user-protocol hook */
+	LIST_ENTRY(protosw)  pr_fasttimos;
+	LIST_ENTRY(protosw)  pr_slowtimos;
 };
 /*#endif*/