From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jiri Pirko Subject: [patch net-next v4 02/12] net: sched: Avoid implicit chain 0 creation Date: Mon, 23 Jul 2018 09:23:05 +0200 Message-ID: <20180723072312.4153-3-jiri@resnulli.us> References: <20180723072312.4153-1-jiri@resnulli.us> Cc: davem@davemloft.net, jhs@mojatatu.com, xiyou.wangcong@gmail.com, jakub.kicinski@netronome.com, simon.horman@netronome.com, john.hurley@netronome.com, dsahern@gmail.com, mlxsw@mellanox.com, sridhar.samudrala@intel.com To: netdev@vger.kernel.org Return-path: Received: from mail-wm0-f65.google.com ([74.125.82.65]:52230 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387923AbeGWIZ3 (ORCPT ); Mon, 23 Jul 2018 04:25:29 -0400 Received: by mail-wm0-f65.google.com with SMTP id o11-v6so43949wmh.2 for ; Mon, 23 Jul 2018 00:25:38 -0700 (PDT) In-Reply-To: <20180723072312.4153-1-jiri@resnulli.us> Sender: netdev-owner@vger.kernel.org List-ID: From: Jiri Pirko Currently, chain 0 is implicitly created during block creation. However that does not align with chain object exposure, creation and destruction api introduced later on. So make the chain 0 behave the same way as any other chain and only create it when it is needed. Since chain 0 is somehow special as the qdiscs need to hold pointer to the first chain tp, this requires to move the chain head change callback infra to the block structure. Signed-off-by: Jiri Pirko --- v3->v4: - new patch --- include/net/sch_generic.h | 5 ++- net/sched/cls_api.c | 86 +++++++++++++++++++++-------------------------- 2 files changed, 43 insertions(+), 48 deletions(-) diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h index 7432100027b7..86f4651784e8 100644 --- a/include/net/sch_generic.h +++ b/include/net/sch_generic.h @@ -300,7 +300,6 @@ typedef void tcf_chain_head_change_t(struct tcf_proto *tp_head, void *priv); struct tcf_chain { struct tcf_proto __rcu *filter_chain; - struct list_head filter_chain_list; struct list_head list; struct tcf_block *block; u32 index; /* chain index */ @@ -318,6 +317,10 @@ struct tcf_block { bool keep_dst; unsigned int offloadcnt; /* Number of oddloaded filters */ unsigned int nooffloaddevcnt; /* Number of devs unable to do offload */ + struct { + struct tcf_chain *chain; + struct list_head filter_chain_list; + } chain0; }; static inline void tcf_block_offload_inc(struct tcf_block *block, u32 *flags) diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c index 6bf91a12e01a..d26fed194870 100644 --- a/net/sched/cls_api.c +++ b/net/sched/cls_api.c @@ -204,11 +204,12 @@ static struct tcf_chain *tcf_chain_create(struct tcf_block *block, chain = kzalloc(sizeof(*chain), GFP_KERNEL); if (!chain) return NULL; - INIT_LIST_HEAD(&chain->filter_chain_list); list_add_tail(&chain->list, &block->chain_list); chain->block = block; chain->index = chain_index; chain->refcnt = 1; + if (!chain->index) + block->chain0.chain = chain; return chain; } @@ -218,12 +219,16 @@ static void tcf_chain_head_change_item(struct tcf_filter_chain_list_item *item, if (item->chain_head_change) item->chain_head_change(tp_head, item->chain_head_change_priv); } -static void tcf_chain_head_change(struct tcf_chain *chain, - struct tcf_proto *tp_head) + +static void tcf_chain0_head_change(struct tcf_chain *chain, + struct tcf_proto *tp_head) { struct tcf_filter_chain_list_item *item; + struct tcf_block *block = chain->block; - list_for_each_entry(item, &chain->filter_chain_list, list) + if (chain->index) + return; + list_for_each_entry(item, &block->chain0.filter_chain_list, list) tcf_chain_head_change_item(item, tp_head); } @@ -231,7 +236,7 @@ static void tcf_chain_flush(struct tcf_chain *chain) { struct tcf_proto *tp = rtnl_dereference(chain->filter_chain); - tcf_chain_head_change(chain, NULL); + tcf_chain0_head_change(chain, NULL); while (tp) { RCU_INIT_POINTER(chain->filter_chain, tp->next); tcf_proto_destroy(tp, NULL); @@ -245,8 +250,10 @@ static void tcf_chain_destroy(struct tcf_chain *chain) struct tcf_block *block = chain->block; list_del(&chain->list); + if (!chain->index) + block->chain0.chain = NULL; kfree(chain); - if (list_empty(&block->chain_list)) + if (list_empty(&block->chain_list) && block->refcnt == 0) kfree(block); } @@ -346,10 +353,11 @@ static void tcf_block_offload_unbind(struct tcf_block *block, struct Qdisc *q, } static int -tcf_chain_head_change_cb_add(struct tcf_chain *chain, - struct tcf_block_ext_info *ei, - struct netlink_ext_ack *extack) +tcf_chain0_head_change_cb_add(struct tcf_block *block, + struct tcf_block_ext_info *ei, + struct netlink_ext_ack *extack) { + struct tcf_chain *chain0 = block->chain0.chain; struct tcf_filter_chain_list_item *item; item = kmalloc(sizeof(*item), GFP_KERNEL); @@ -359,23 +367,25 @@ tcf_chain_head_change_cb_add(struct tcf_chain *chain, } item->chain_head_change = ei->chain_head_change; item->chain_head_change_priv = ei->chain_head_change_priv; - if (chain->filter_chain) - tcf_chain_head_change_item(item, chain->filter_chain); - list_add(&item->list, &chain->filter_chain_list); + if (chain0 && chain0->filter_chain) + tcf_chain_head_change_item(item, chain0->filter_chain); + list_add(&item->list, &block->chain0.filter_chain_list); return 0; } static void -tcf_chain_head_change_cb_del(struct tcf_chain *chain, - struct tcf_block_ext_info *ei) +tcf_chain0_head_change_cb_del(struct tcf_block *block, + struct tcf_block_ext_info *ei) { + struct tcf_chain *chain0 = block->chain0.chain; struct tcf_filter_chain_list_item *item; - list_for_each_entry(item, &chain->filter_chain_list, list) { + list_for_each_entry(item, &block->chain0.filter_chain_list, list) { if ((!ei->chain_head_change && !ei->chain_head_change_priv) || (item->chain_head_change == ei->chain_head_change && item->chain_head_change_priv == ei->chain_head_change_priv)) { - tcf_chain_head_change_item(item, NULL); + if (chain0) + tcf_chain_head_change_item(item, NULL); list_del(&item->list); kfree(item); return; @@ -411,8 +421,6 @@ static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q, struct netlink_ext_ack *extack) { struct tcf_block *block; - struct tcf_chain *chain; - int err; block = kzalloc(sizeof(*block), GFP_KERNEL); if (!block) { @@ -422,14 +430,8 @@ static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q, INIT_LIST_HEAD(&block->chain_list); INIT_LIST_HEAD(&block->cb_list); INIT_LIST_HEAD(&block->owner_list); + INIT_LIST_HEAD(&block->chain0.filter_chain_list); - /* Create chain 0 by default, it has to be always present. */ - chain = tcf_chain_create(block, 0); - if (!chain) { - NL_SET_ERR_MSG(extack, "Failed to create new tcf chain"); - err = -ENOMEM; - goto err_chain_create; - } block->refcnt = 1; block->net = net; block->index = block_index; @@ -438,10 +440,6 @@ static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q, if (!tcf_block_shared(block)) block->q = q; return block; - -err_chain_create: - kfree(block); - return ERR_PTR(err); } static struct tcf_block *tcf_block_lookup(struct net *net, u32 block_index) @@ -523,11 +521,6 @@ static struct tcf_block *tcf_block_find(struct net *net, struct Qdisc **q, return block; } -static struct tcf_chain *tcf_block_chain_zero(struct tcf_block *block) -{ - return list_first_entry(&block->chain_list, struct tcf_chain, list); -} - struct tcf_block_owner_item { struct list_head list; struct Qdisc *q; @@ -621,10 +614,9 @@ int tcf_block_get_ext(struct tcf_block **p_block, struct Qdisc *q, tcf_block_owner_netif_keep_dst(block, q, ei->binder_type); - err = tcf_chain_head_change_cb_add(tcf_block_chain_zero(block), - ei, extack); + err = tcf_chain0_head_change_cb_add(block, ei, extack); if (err) - goto err_chain_head_change_cb_add; + goto err_chain0_head_change_cb_add; err = tcf_block_offload_bind(block, q, ei, extack); if (err) @@ -634,15 +626,14 @@ int tcf_block_get_ext(struct tcf_block **p_block, struct Qdisc *q, return 0; err_block_offload_bind: - tcf_chain_head_change_cb_del(tcf_block_chain_zero(block), ei); -err_chain_head_change_cb_add: + tcf_chain0_head_change_cb_del(block, ei); +err_chain0_head_change_cb_add: tcf_block_owner_del(block, q, ei->binder_type); err_block_owner_add: if (created) { if (tcf_block_shared(block)) tcf_block_remove(block, net); err_block_insert: - kfree(tcf_block_chain_zero(block)); kfree(block); } else { block->refcnt--; @@ -682,10 +673,10 @@ void tcf_block_put_ext(struct tcf_block *block, struct Qdisc *q, if (!block) return; - tcf_chain_head_change_cb_del(tcf_block_chain_zero(block), ei); + tcf_chain0_head_change_cb_del(block, ei); tcf_block_owner_del(block, q, ei->binder_type); - if (--block->refcnt == 0) { + if (block->refcnt == 1) { if (tcf_block_shared(block)) tcf_block_remove(block, block->net); @@ -701,13 +692,14 @@ void tcf_block_put_ext(struct tcf_block *block, struct Qdisc *q, tcf_block_offload_unbind(block, q, ei); - if (block->refcnt == 0) { + if (block->refcnt == 1) { /* At this point, all the chains should have refcnt >= 1. */ list_for_each_entry_safe(chain, tmp, &block->chain_list, list) tcf_chain_put(chain); - /* Finally, put chain 0 and allow block to be freed. */ - tcf_chain_put(tcf_block_chain_zero(block)); + block->refcnt--; + if (list_empty(&block->chain_list)) + kfree(block); } } EXPORT_SYMBOL(tcf_block_put_ext); @@ -947,7 +939,7 @@ static void tcf_chain_tp_insert(struct tcf_chain *chain, struct tcf_proto *tp) { if (*chain_info->pprev == chain->filter_chain) - tcf_chain_head_change(chain, tp); + tcf_chain0_head_change(chain, tp); RCU_INIT_POINTER(tp->next, tcf_chain_tp_prev(chain_info)); rcu_assign_pointer(*chain_info->pprev, tp); tcf_chain_hold(chain); @@ -960,7 +952,7 @@ static void tcf_chain_tp_remove(struct tcf_chain *chain, struct tcf_proto *next = rtnl_dereference(chain_info->next); if (tp == chain->filter_chain) - tcf_chain_head_change(chain, next); + tcf_chain0_head_change(chain, next); RCU_INIT_POINTER(*chain_info->pprev, next); tcf_chain_put(chain); } -- 2.14.4