gro: consistentify napi->gro_hash[x] access in dev_gro_receive()

GRO bucket index doesn't change through the entire function.
Store a pointer to the corresponding bucket instead of its member
and use it consistently through the function.
It is performance-safe since &gro_list->list == gro_list.

Misc: remove superfluous braces around single-line branches.

Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/core/dev.c b/net/core/dev.c
index 1317e6b6758a5de1b0079097dd4708aebdcfbf76..b635467087f3d2306ede93efbdbaaf2df05f8e0b 100644 (file)
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -5953,7 +5953,7 @@ static void gro_flush_oldest(struct napi_struct *napi, struct list_head *head)
 static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
 {
        u32 hash = skb_get_hash_raw(skb) & (GRO_HASH_BUCKETS - 1);
-       struct list_head *gro_head = &napi->gro_hash[hash].list;
+       struct gro_list *gro_list = &napi->gro_hash[hash];
        struct list_head *head = &offload_base;
        struct packet_offload *ptype;
        __be16 type = skb->protocol;
@@ -5965,7 +5965,7 @@ static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff
        if (netif_elide_gro(skb->dev))
                goto normal;
 
-       gro_list_prepare(gro_head, skb);
+       gro_list_prepare(&gro_list->list, skb);
 
        rcu_read_lock();
        list_for_each_entry_rcu(ptype, head, list) {
@@ -6001,7 +6001,7 @@ static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff
 
                pp = INDIRECT_CALL_INET(ptype->callbacks.gro_receive,
                                        ipv6_gro_receive, inet_gro_receive,
-                                       gro_head, skb);
+                                       &gro_list->list, skb);
                break;
        }
        rcu_read_unlock();
@@ -6020,7 +6020,7 @@ static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff
        if (pp) {
                skb_list_del_init(pp);
                napi_gro_complete(napi, pp);
-               napi->gro_hash[hash].count--;
+               gro_list->count--;
        }
 
        if (same_flow)
@@ -6029,16 +6029,16 @@ static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff
        if (NAPI_GRO_CB(skb)->flush)
                goto normal;
 
-       if (unlikely(napi->gro_hash[hash].count >= MAX_GRO_SKBS)) {
-               gro_flush_oldest(napi, gro_head);
-       } else {
-               napi->gro_hash[hash].count++;
-       }
+       if (unlikely(gro_list->count >= MAX_GRO_SKBS))
+               gro_flush_oldest(napi, &gro_list->list);
+       else
+               gro_list->count++;
+
        NAPI_GRO_CB(skb)->count = 1;
        NAPI_GRO_CB(skb)->age = jiffies;
        NAPI_GRO_CB(skb)->last = skb;
        skb_shinfo(skb)->gso_size = skb_gro_len(skb);
-       list_add(&skb->list, gro_head);
+       list_add(&skb->list, &gro_list->list);
        ret = GRO_HELD;
 
 pull:
@@ -6046,7 +6046,7 @@ pull:
        if (grow > 0)
                gro_pull_from_frag0(skb, grow);
 ok:
-       if (napi->gro_hash[hash].count) {
+       if (gro_list->count) {
                if (!test_bit(hash, &napi->gro_bitmask))
                        __set_bit(hash, &napi->gro_bitmask);
        } else if (test_bit(hash, &napi->gro_bitmask)) {