| Message ID | 20180908.131104.39421839190166239.davem@davemloft.net |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
| Series | SKB list handling cleanups | expand |
Hello! On 9/8/2018 11:11 PM, David Miller wrote: > It documents what is happening, and eliminates the spurious list > pointer poisoning. > > In the long term, in order to get proper list head debugging, we > might want to use the list poinson value as the indicator that Poison? > an SKB is a singleton and not on a list. > > Signed-off-by: David S. Miller <davem@davemloft.net> [...] MBR, Sergei
From: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Date: Sun, 9 Sep 2018 12:45:50 +0300 > Hello! > > On 9/8/2018 11:11 PM, David Miller wrote: > >> It documents what is happening, and eliminates the spurious list >> pointer poisoning. >> In the long term, in order to get proper list head debugging, we >> might want to use the list poinson value as the indicator that > > Poison? I knew you would find something Sergei :-) I'll fix that up, thanks.
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index c4c9e3f5cd9a..e3a53ca4a9b5 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -1344,6 +1344,12 @@ static inline void skb_mark_not_on_list(struct sk_buff *skb) skb->next = NULL; } +static inline void skb_list_del_init(struct sk_buff *skb) +{ + __list_del_entry(&skb->list); + skb_mark_not_on_list(skb); +} + /** * skb_queue_empty - check if a queue is empty * @list: queue head diff --git a/net/core/dev.c b/net/core/dev.c index f76dd7e14dd6..0b2d777e5b9e 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -5295,8 +5295,7 @@ static void __napi_gro_flush_chain(struct napi_struct *napi, u32 index, list_for_each_entry_safe_reverse(skb, p, head, list) { if (flush_old && NAPI_GRO_CB(skb)->age == jiffies) return; - list_del(&skb->list); - skb_mark_not_on_list(skb); + skb_list_del_init(skb); napi_gro_complete(skb); napi->gro_hash[index].count--; } @@ -5481,8 +5480,7 @@ static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED; if (pp) { - list_del(&pp->list); - skb_mark_not_on_list(pp); + skb_list_del_init(pp); napi_gro_complete(pp); napi->gro_hash[hash].count--; } diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c index eba7f3883230..35a786c0aaa0 100644 --- a/net/ipv4/ip_input.c +++ b/net/ipv4/ip_input.c @@ -531,11 +531,7 @@ static void ip_sublist_rcv_finish(struct list_head *head) struct sk_buff *skb, *next; list_for_each_entry_safe(skb, next, head, list) { - list_del(&skb->list); - /* Handle ip{6}_forward case, as sch_direct_xmit have - * another kind of SKB-list usage (see validate_xmit_skb_list) - */ - skb_mark_not_on_list(skb); + skb_list_del_init(skb); dst_input(skb); } }
It documents what is happening, and eliminates the spurious list pointer poisoning. In the long term, in order to get proper list head debugging, we might want to use the list poinson value as the indicator that an SKB is a singleton and not on a list. Signed-off-by: David S. Miller <davem@davemloft.net> --- include/linux/skbuff.h | 6 ++++++ net/core/dev.c | 6 ++---- net/ipv4/ip_input.c | 6 +----- 3 files changed, 9 insertions(+), 9 deletions(-)