[PATCH 3/5] net: core: Use FIELD_SIZEOF directly instead of reimplementing its function

From: zhong jiang
Date: Wed Sep 19 2018 - 06:39:02 EST


FIELD_SIZEOF is defined as a macro to calculate the specified value. Therefore,
We prefer to use the macro rather than calculating its value.

Signed-off-by: zhong jiang <zhongjiang@xxxxxxxxxx>
---
net/core/flow_dissector.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
index 5c5dd74..aeac884 100644
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -423,8 +423,8 @@ __be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto,
offset += sizeof(struct gre_base_hdr);

if (hdr->flags & GRE_CSUM)
- offset += sizeof(((struct gre_full_hdr *) 0)->csum) +
- sizeof(((struct gre_full_hdr *) 0)->reserved1);
+ offset += FIELD_SIZEOF(struct gre_full_hdr, csum) +
+ FIELD_SIZEOF(struct gre_full_hdr, reserved1);

if (hdr->flags & GRE_KEY) {
const __be32 *keyid;
@@ -446,11 +446,11 @@ __be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto,
else
key_keyid->keyid = *keyid & GRE_PPTP_KEY_MASK;
}
- offset += sizeof(((struct gre_full_hdr *) 0)->key);
+ offset += FIELD_SIZEOF(struct gre_full_hdr, key);
}

if (hdr->flags & GRE_SEQ)
- offset += sizeof(((struct pptp_gre_header *) 0)->seq);
+ offset += FIELD_SIZEOF(struct pptp_gre_header, seq);

if (gre_ver == 0) {
if (*p_proto == htons(ETH_P_TEB)) {
@@ -477,7 +477,7 @@ __be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto,
u8 *ppp_hdr;

if (hdr->flags & GRE_ACK)
- offset += sizeof(((struct pptp_gre_header *) 0)->ack);
+ offset += FIELD_SIZEOF(struct pptp_gre_header, ack);

ppp_hdr = __skb_header_pointer(skb, *p_nhoff + offset,
sizeof(_ppp_hdr),
--
1.7.12.4