Commit 20df28fb authored by Breno Leitao's avatar Breno Leitao Committed by Jakub Kicinski
Browse files

net/ipv6: resolve warning in ip6_fib.c 

In some configurations, the 'iter' variable in function
fib6_repair_tree() is unused, resulting the following warning when
compiled with W=1.

    net/ipv6/ip6_fib.c:1781:6: warning: variable 'iter' set but not used [-Wunused-but-set-variable]
     1781 |         int iter = 0;
	  |             ^

It is unclear what is the advantage of this RT6_TRACE() macro[1], since
users can control pr_debug() in runtime, which is better than at
compilation time. pr_debug() has no overhead when disabled.

Remove the RT6_TRACE() in favor of simple pr_debug() helpers.

[1] Link: https://lore.kernel.org/all/ZZwSEJv2HgI0cD4J@gmail.com/


Signed-off-by: default avatarBreno Leitao <leitao@debian.org>
Reviewed-by: default avatarDavid Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240122181955.2391676-2-leitao@debian.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent a6348a71

include/net/ip6_fib.h

+0 −6
Original line number Diff line number Diff line
@@ -30,12 +30,6 @@ 


#define RT6_DEBUG 2



#if RT6_DEBUG >= 3

#define RT6_TRACE(x...) pr_debug(x)

#else

#define RT6_TRACE(x...) do { ; } while (0)

#endif



struct rt6_info;

struct fib6_info;

net/ipv6/ip6_fib.c

+9 −6
Original line number Diff line number Diff line
@@ -1801,7 +1801,7 @@ static struct fib6_node *fib6_repair_tree(struct net *net, 
					    lockdep_is_held(&table->tb6_lock));

		struct fib6_info *new_fn_leaf;



		RT6_TRACE("fixing tree: plen=%d iter=%d\n", fn->fn_bit, iter);

		pr_debug("fixing tree: plen=%d iter=%d\n", fn->fn_bit, iter);

		iter++;



		WARN_ON(fn->fn_flags & RTN_RTINFO);
@@ -1864,7 +1864,8 @@ static struct fib6_node *fib6_repair_tree(struct net *net, 
		FOR_WALKERS(net, w) {

			if (!child) {

				if (w->node == fn) {

					RT6_TRACE("W %p adjusted by delnode 1, s=%d/%d\n", w, w->state, nstate);

					pr_debug("W %p adjusted by delnode 1, s=%d/%d\n",

						 w, w->state, nstate);

					w->node = pn;

					w->state = nstate;

				}
@@ -1872,10 +1873,12 @@ static struct fib6_node *fib6_repair_tree(struct net *net, 
				if (w->node == fn) {

					w->node = child;

					if (children&2) {

						RT6_TRACE("W %p adjusted by delnode 2, s=%d\n", w, w->state);

						pr_debug("W %p adjusted by delnode 2, s=%d\n",

							 w, w->state);

						w->state = w->state >= FWS_R ? FWS_U : FWS_INIT;

					} else {

						RT6_TRACE("W %p adjusted by delnode 2, s=%d\n", w, w->state);

						pr_debug("W %p adjusted by delnode 2, s=%d\n",

							 w, w->state);

						w->state = w->state >= FWS_C ? FWS_U : FWS_INIT;

					}

				}
@@ -1951,7 +1954,7 @@ static void fib6_del_route(struct fib6_table *table, struct fib6_node *fn, 
	read_lock(&net->ipv6.fib6_walker_lock);

	FOR_WALKERS(net, w) {

		if (w->state == FWS_C && w->leaf == rt) {

			RT6_TRACE("walker %p adjusted by delroute\n", w);

			pr_debug("walker %p adjusted by delroute\n", w);

			w->leaf = rcu_dereference_protected(rt->fib6_next,

					    lockdep_is_held(&table->tb6_lock));

			if (!w->leaf)
@@ -2289,7 +2292,7 @@ static int fib6_age(struct fib6_info *rt, void *arg) 


	if (rt->fib6_flags & RTF_EXPIRES && rt->expires) {

		if (time_after(now, rt->expires)) {

			RT6_TRACE("expiring %p\n", rt);

			pr_debug("expiring %p\n", rt);

			return -1;

		}

		gc_args->more++;

net/ipv6/route.c

+4 −4
Original line number Diff line number Diff line
@@ -2085,12 +2085,12 @@ static void rt6_age_examine_exception(struct rt6_exception_bucket *bucket, 
	 */

	if (!(rt->rt6i_flags & RTF_EXPIRES)) {

		if (time_after_eq(now, rt->dst.lastuse + gc_args->timeout)) {

			RT6_TRACE("aging clone %p\n", rt);

			pr_debug("aging clone %p\n", rt);

			rt6_remove_exception(bucket, rt6_ex);

			return;

		}

	} else if (time_after(jiffies, rt->dst.expires)) {

		RT6_TRACE("purging expired route %p\n", rt);

		pr_debug("purging expired route %p\n", rt);

		rt6_remove_exception(bucket, rt6_ex);

		return;

	}
@@ -2101,7 +2101,7 @@ static void rt6_age_examine_exception(struct rt6_exception_bucket *bucket, 
		neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);



		if (!(neigh && (neigh->flags & NTF_ROUTER))) {

			RT6_TRACE("purging route %p via non-router but gateway\n",

			pr_debug("purging route %p via non-router but gateway\n",

				 rt);

			rt6_remove_exception(bucket, rt6_ex);

			return;