From 1bab4c75075b84675b96992ac47580a57c26958d Mon Sep 17 00:00:00 2001 From: Nikolay Aleksandrov Date: Thu, 24 Jul 2014 16:50:37 +0200 Subject: inet: frag: set limits and make init_net's high_thresh limit global This patch makes init_net's high_thresh limit to be the maximum for all namespaces, thus introducing a global memory limit threshold equal to the sum of the individual high_thresh limits which are capped. It also introduces some sane minimums for low_thresh as it shouldn't be able to drop below 0 (or > high_thresh in the unsigned case), and overall low_thresh should not ever be above high_thresh, so we make the following relations for a namespace: init_net: high_thresh - max(not capped), min(init_net low_thresh) low_thresh - max(init_net high_thresh), min (0) all other namespaces: high_thresh = max(init_net high_thresh), min(namespace's low_thresh) low_thresh = max(namespace's high_thresh), min(0) The major issue with having low_thresh > high_thresh is that we'll schedule eviction but never evict anything and thus rely only on the timers. Signed-off-by: Nikolay Aleksandrov Signed-off-by: David S. Miller --- net/ieee802154/reassembly.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) (limited to 'net/ieee802154/reassembly.c') diff --git a/net/ieee802154/reassembly.c b/net/ieee802154/reassembly.c index 8da635d92a58..f13d4f32e207 100644 --- a/net/ieee802154/reassembly.c +++ b/net/ieee802154/reassembly.c @@ -386,20 +386,25 @@ err: EXPORT_SYMBOL(lowpan_frag_rcv); #ifdef CONFIG_SYSCTL +static int zero; + static struct ctl_table lowpan_frags_ns_ctl_table[] = { { .procname = "6lowpanfrag_high_thresh", .data = &init_net.ieee802154_lowpan.frags.high_thresh, .maxlen = sizeof(int), .mode = 0644, - .proc_handler = proc_dointvec + .proc_handler = proc_dointvec_minmax, + .extra1 = &init_net.ieee802154_lowpan.frags.low_thresh }, { .procname = "6lowpanfrag_low_thresh", .data = &init_net.ieee802154_lowpan.frags.low_thresh, .maxlen = sizeof(int), .mode = 0644, - .proc_handler = proc_dointvec + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &init_net.ieee802154_lowpan.frags.high_thresh }, { .procname = "6lowpanfrag_time", @@ -446,7 +451,10 @@ static int __net_init lowpan_frags_ns_sysctl_register(struct net *net) goto err_alloc; table[0].data = &ieee802154_lowpan->frags.high_thresh; + table[0].extra1 = &ieee802154_lowpan->frags.low_thresh; + table[0].extra2 = &init_net.ieee802154_lowpan.frags.high_thresh; table[1].data = &ieee802154_lowpan->frags.low_thresh; + table[1].extra2 = &ieee802154_lowpan->frags.high_thresh; table[2].data = &ieee802154_lowpan->frags.timeout; table[3].data = &ieee802154_lowpan->max_dsize; -- cgit v1.2.3-55-g7522