xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

net: Allow GRO to use and set levels of checksum unnecessary

Browse Source 
Allow GRO path to "consume" checksums provided in CHECKSUM_UNNECESSARY
and to report new checksums verfied for use in fallback to normal
path.

Change GRO checksum path to track csum_level using a csum_cnt field
in NAPI_GRO_CB. On GRO initialization, if ip_summed is
CHECKSUM_UNNECESSARY set NAPI_GRO_CB(skb)->csum_cnt to
skb->csum_level + 1. For each checksum verified, decrement
NAPI_GRO_CB(skb)->csum_cnt while its greater than zero. If a checksum
is verfied and NAPI_GRO_CB(skb)->csum_cnt == 0, we have verified a
deeper checksum than originally indicated in skbuf so increment
csum_level (or initialize to CHECKSUM_UNNECESSARY if ip_summed is
CHECKSUM_NONE or CHECKSUM_COMPLETE).

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Tom Herbert
2014-08-27 21:26:56 -07:00
committed by David S. Miller
parent 77cffe23c1
commit 662880f442
4 changed files with 33 additions and 29 deletions
Download Patch File Download Diff File Expand all files Collapse all files

26
include/linux/netdevice.h
View File

@@ -1883,8 +1883,8 @@ struct napi_gro_cb {
/* GRO checksum is valid */
u8 csum_valid:1;
/* Number encapsulation layers crossed */
u8 encapsulation;
/* Number of checksums via CHECKSUM_UNNECESSARY */
u8 csum_cnt:3;
/* used to support CHECKSUM_COMPLETE for tunneling protocols */
__wsum csum;
@@ -2179,8 +2179,7 @@ static inline bool __skb_gro_checksum_validate_needed(struct sk_buff *skb,
__sum16 check)
{
return (skb->ip_summed != CHECKSUM_PARTIAL &&
(skb->ip_summed != CHECKSUM_UNNECESSARY ||
(NAPI_GRO_CB(skb)->encapsulation > skb->encapsulation)) &&
NAPI_GRO_CB(skb)->csum_cnt == 0 &&
(!zero_okay || check));
}
@@ -2196,18 +2195,17 @@ static inline __sum16 __skb_gro_checksum_validate_complete(struct sk_buff *skb,
return __skb_gro_checksum_complete(skb);
}
/* Update skb for CHECKSUM_UNNECESSARY when we verified a top level
* checksum or an encapsulated one during GRO. This saves work
* if we fallback to normal path with the packet.
*/
static inline void skb_gro_incr_csum_unnecessary(struct sk_buff *skb)
{
if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
if (NAPI_GRO_CB(skb)->encapsulation)
skb->encapsulation = 1;
} else if (skb->ip_summed != CHECKSUM_PARTIAL) {
skb->ip_summed = CHECKSUM_UNNECESSARY;
skb->encapsulation = 0;
if (NAPI_GRO_CB(skb)->csum_cnt > 0) {
/* Consume a checksum from CHECKSUM_UNNECESSARY */
NAPI_GRO_CB(skb)->csum_cnt--;
} else {
/* Update skb for CHECKSUM_UNNECESSARY and csum_level when we
* verified a new top level checksum or an encapsulated one
* during GRO. This saves work if we fallback to normal path.
*/
__skb_incr_checksum_unnecessary(skb);
}
}