@@ -67,6 +67,7 @@ struct conntrack_gc_work {
struct delayed_work dwork;
u32 next_bucket;
u32 avg_timeout;
+ u32 count;
u32 start_time;
bool exiting;
bool early_drop;
@@ -1466,6 +1467,7 @@ static void gc_worker(struct work_struct *work)
unsigned int expired_count = 0;
unsigned long next_run;
s32 delta_time;
+ long count;
gc_work = container_of(work, struct conntrack_gc_work, dwork.work);
@@ -1475,10 +1477,12 @@ static void gc_worker(struct work_struct *work)
if (i == 0) {
gc_work->avg_timeout = GC_SCAN_INTERVAL_INIT;
+ gc_work->count = 1;
gc_work->start_time = start_time;
}
next_run = gc_work->avg_timeout;
+ count = gc_work->count;
end_time = start_time + GC_SCAN_MAX_DURATION;
@@ -1498,8 +1502,8 @@ static void gc_worker(struct work_struct *work)
hlist_nulls_for_each_entry_rcu(h, n, &ct_hash[i], hnnode) {
struct nf_conntrack_net *cnet;
- unsigned long expires;
struct net *net;
+ long expires;
tmp = nf_ct_tuplehash_to_ctrack(h);
@@ -1513,6 +1517,7 @@ static void gc_worker(struct work_struct *work)
gc_work->next_bucket = i;
gc_work->avg_timeout = next_run;
+ gc_work->count = count;
delta_time = nfct_time_stamp - gc_work->start_time;
@@ -1528,8 +1533,8 @@ static void gc_worker(struct work_struct *work)
}
expires = clamp(nf_ct_expires(tmp), GC_SCAN_INTERVAL_MIN, GC_SCAN_INTERVAL_CLAMP);
+ expires = (expires - (long)next_run) / ++count;
next_run += expires;
- next_run /= 2u;
if (nf_conntrack_max95 == 0 || gc_worker_skip_ct(tmp))
continue;
@@ -1570,6 +1575,7 @@ static void gc_worker(struct work_struct *work)
delta_time = nfct_time_stamp - end_time;
if (delta_time > 0 && i < hashsz) {
gc_work->avg_timeout = next_run;
+ gc_work->count = count;
gc_work->next_bucket = i;
next_run = 0;
goto early_exit;
Commit 2cfadb761d3d ("netfilter: conntrack: revisit gc autotuning") changed the eviction rescheduling to the use average expiry of scanned entries (within 1-60s) by doing: for (...) { expires = clamp(nf_ct_expires(tmp), ...); next_run += expires; next_run /= 2; } The issue is the above will make the average ('next_run' here) more dependent on the last expiration values than the firsts (for sets > 2). Depending on the expiration values used to compute the average, the result can be quite different than what's expected. To fix this we can do the following: for (...) { expires = clamp(nf_ct_expires(tmp), ...); next_run += (expires - next_run) / ++count; } Fixes: 2cfadb761d3d ("netfilter: conntrack: revisit gc autotuning") Cc: Florian Westphal <fw@strlen.de> Signed-off-by: Antoine Tenart <atenart@kernel.org> --- net/netfilter/nf_conntrack_core.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)