Add a new sysctl net.inet.tcp.hostcache.purgenow=1 to expire and purge all

entries in hostcache immediately.

In collaboration with:	bz, rwatson
MFC after:	1 week
Relnotes:	yes
Sponsored by:	Limelight Networks

1 files changed, 25 insertions, 0 deletions

diff --git a/sys/netinet/tcp_hostcache.c b/sys/netinet/tcp_hostcache.c
index ca13f27edd93..6ff447ce2e35 100644
--- a/sys/netinet/tcp_hostcache.c
+++ b/sys/netinet/tcp_hostcache.c
@@ -117,6 +117,7 @@ static VNET_DEFINE(struct callout, tcp_hc_callout);
 static struct hc_metrics *tcp_hc_lookup(struct in_conninfo *);
 static struct hc_metrics *tcp_hc_insert(struct in_conninfo *);
 static int sysctl_tcp_hc_list(SYSCTL_HANDLER_ARGS);
+static int sysctl_tcp_hc_purgenow(SYSCTL_HANDLER_ARGS);
 static void tcp_hc_purge_internal(int);
 static void tcp_hc_purge(void *);
 
@@ -155,6 +156,9 @@ SYSCTL_PROC(_net_inet_tcp_hostcache, OID_AUTO, list,
     CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_SKIP, 0, 0,
     sysctl_tcp_hc_list, "A", "List of all hostcache entries");
 
+SYSCTL_PROC(_net_inet_tcp_hostcache, OID_AUTO, purgenow,
+    CTLTYPE_INT | CTLFLAG_RW, NULL, 0,
+    sysctl_tcp_hc_purgenow, "I", "Immediately purge all entries");
 
 static MALLOC_DEFINE(M_HOSTCACHE, "hostcache", "TCP hostcache");
 
@@ -696,3 +700,24 @@ tcp_hc_purge(void *arg)
 	    tcp_hc_purge, arg);
 	CURVNET_RESTORE();
 }
+
+/*
+ * Expire and purge all entries in hostcache immediately.
+ */
+static int
+sysctl_tcp_hc_purgenow(SYSCTL_HANDLER_ARGS)
+{
+	int error, val;
+
+	val = 0;
+	error = sysctl_handle_int(oidp, &val, 0, req);
+	if (error || !req->newptr)
+		return (error);
+
+	tcp_hc_purge_internal(1);
+
+	callout_reset(&V_tcp_hc_callout, V_tcp_hostcache.prune * hz,
+	    tcp_hc_purge, curvnet);
+
+	return (0);
+}