[IPV4]: Kill MULTIPATHHOLDROUTE flag.

It cannot work properly, so just ignore it in drr
and rr multipath algorithms just like the random
multipath algorithm does.

Suggested by Herbert Xu.

Signed-off by: Pravin B. Shelar <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

include/net/route.h

···
 		memcpy(&fl, &(*rp)->fl, sizeof(fl));
 		fl.fl_ip_sport = sport;
 		fl.fl_ip_dport = dport;
-#if defined(CONFIG_IP_ROUTE_MULTIPATH_CACHED)
-		fl.flags |= FLOWI_FLAG_MULTIPATHOLDROUTE;
-#endif
 		ip_rt_put(*rp);
 		*rp = NULL;
 		return ip_route_output_flow(rp, &fl, sk, 0);

net/ipv4/multipath_drr.c

···
 
 static struct multipath_device state[MULTIPATH_MAX_DEVICECANDIDATES];
 static DEFINE_SPINLOCK(state_lock);
-static struct rtable *last_selection = NULL;
 
 static int inline __multipath_findslot(void)
 {
···
 	.notifier_call	= drr_dev_event,
 };
 
-static void drr_remove(struct rtable *rt)
-{
-	if (last_selection == rt)
-		last_selection = NULL;
-}
 
 static void drr_safe_inc(atomic_t *usecount)
 {
···
 	int min_usecount = -1; 
 	int devidx = -1;
 	int cur_min_devidx = -1;
-
-       	/* if necessary and possible utilize the old alternative */
-	if ((flp->flags & FLOWI_FLAG_MULTIPATHOLDROUTE) != 0 &&
-	    last_selection != NULL) {
-		result = last_selection;
-		*rp = result;
-		return;
-	}
 
 	/* 1. make sure all alt. nexthops have the same GC related data */
 	/* 2. determine the new candidate to be returned */
···
 	}
 
 	*rp = result;
-	last_selection = result;
 }
 
 static struct ip_mp_alg_ops drr_ops = {
 	.mp_alg_select_route	=	drr_select_route,
-	.mp_alg_remove		=	drr_remove,
 };
 
 static int __init drr_init(void)
···
 	if (err)
 		return err;
 
-	err = multipath_alg_register(&drr_ops, IP_MP_ALG_RR);
+	err = multipath_alg_register(&drr_ops, IP_MP_ALG_DRR);
 	if (err)
 		goto fail;
 

net/ipv4/multipath_rr.c

···
 #include <net/checksum.h>
 #include <net/ip_mp_alg.h>
 
-#define MULTIPATH_MAX_CANDIDATES 40
-
-static struct rtable* last_used = NULL;
-
-static void rr_remove(struct rtable *rt)
-{
-	if (last_used == rt)
-		last_used = NULL;
-}
-
 static void rr_select_route(const struct flowi *flp,
 			    struct rtable *first, struct rtable **rp)
 {
 	struct rtable *nh, *result, *min_use_cand = NULL;
 	int min_use = -1;
-
-	/* if necessary and possible utilize the old alternative */
-	if ((flp->flags & FLOWI_FLAG_MULTIPATHOLDROUTE) != 0 &&
-	    last_used != NULL) {
-		result = last_used;
-		goto out;
-	}
 
 	/* 1. make sure all alt. nexthops have the same GC related data
 	 * 2. determine the new candidate to be returned
···
 	if (!result)
 		result = first;
 
-out:
-	last_used = result;
 	result->u.dst.__use++;
 	*rp = result;
 }
 
 static struct ip_mp_alg_ops rr_ops = {
 	.mp_alg_select_route	=	rr_select_route,
-	.mp_alg_remove		=	rr_remove,
 };
 
 static int __init rr_init(void)