[PATCH nf-next] netfilter: hashlimit: do not use indirect calls during gc

[PATCH nf-next] netfilter: hashlimit: do not use indirect calls during gc

[Florian Westphal]

no need, just use a simple boolean to indicate we want to reap all
entries.

Signed-off-by: Florian Westphal <fw@strlen.de>
---
 This is an old patch I had floating around in an odd working branch,
 I think this makes the cleanup logic easier to follow.
 If you disagree just drop this.

 net/netfilter/xt_hashlimit.c | 22 ++++------------------
 1 file changed, 4 insertions(+), 18 deletions(-)

diff --git a/net/netfilter/xt_hashlimit.c b/net/netfilter/xt_hashlimit.c
index ced3fc8fad7c..bccd47cd7190 100644
--- a/net/netfilter/xt_hashlimit.c
+++ b/net/netfilter/xt_hashlimit.c
@@ -357,21 +357,7 @@ static int htable_create(struct net *net, struct hashlimit_cfg3 *cfg,
 	return 0;
 }
 
-static bool select_all(const struct xt_hashlimit_htable *ht,
-		       const struct dsthash_ent *he)
-{
-	return true;
-}
-
-static bool select_gc(const struct xt_hashlimit_htable *ht,
-		      const struct dsthash_ent *he)
-{
-	return time_after_eq(jiffies, he->expires);
-}
-
-static void htable_selective_cleanup(struct xt_hashlimit_htable *ht,
-			bool (*select)(const struct xt_hashlimit_htable *ht,
-				      const struct dsthash_ent *he))
+static void htable_selective_cleanup(struct xt_hashlimit_htable *ht, bool select_all)
 {
 	unsigned int i;
 
@@ -381,7 +367,7 @@ static void htable_selective_cleanup(struct xt_hashlimit_htable *ht,
 
 		spin_lock_bh(&ht->lock);
 		hlist_for_each_entry_safe(dh, n, &ht->hash[i], node) {
-			if ((*select)(ht, dh))
+			if (time_after_eq(jiffies, dh->expires) || select_all)
 				dsthash_free(ht, dh);
 		}
 		spin_unlock_bh(&ht->lock);
@@ -395,7 +381,7 @@ static void htable_gc(struct work_struct *work)
 
 	ht = container_of(work, struct xt_hashlimit_htable, gc_work.work);
 
-	htable_selective_cleanup(ht, select_gc);
+	htable_selective_cleanup(ht, false);
 
 	queue_delayed_work(system_power_efficient_wq,
 			   &ht->gc_work, msecs_to_jiffies(ht->cfg.gc_interval));
@@ -419,7 +405,7 @@ static void htable_destroy(struct xt_hashlimit_htable *hinfo)
 {
 	cancel_delayed_work_sync(&hinfo->gc_work);
 	htable_remove_proc_entry(hinfo);
-	htable_selective_cleanup(hinfo, select_all);
+	htable_selective_cleanup(hinfo, true);
 	kfree(hinfo->name);
 	vfree(hinfo);
 }
-- 
2.24.1

Re: [PATCH nf-next] netfilter: hashlimit: do not use indirect calls during gc

[Pablo Neira Ayuso]

On Tue, Jan 07, 2020 at 12:25:10PM +0100, Florian Westphal wrote:
> no need, just use a simple boolean to indicate we want to reap all
> entries.

Applied, thanks.

> Signed-off-by: Florian Westphal <fw@strlen.de>
> ---
>  This is an old patch I had floating around in an odd working branch,
>  I think this makes the cleanup logic easier to follow.
>  If you disagree just drop this.

No objections.