[Linuxarm] Re: [RFCv7 PATCH net-next 23/36] net: adjust the build check for net_gso_ok()

在 2022/8/10 19:09, Alexander Lobakin 写道:

From: Jian Shen shenjian15@huawei.com Date: Wed, 10 Aug 2022 11:06:11 +0800

...

Introduce macro GSO_INDEX(x) to replace the NETIF_F_XXX feature shift check, for all the macroes NETIF_F_XXX will be remove later.

Signed-off-by: Jian Shen shenjian15@huawei.com

include/linux/netdevice.h | 40 ++++++++++++++++++++------------------- 1 file changed, 21 insertions(+), 19 deletions(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 1bd5dcbc884d..b01af2a3838d 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -4886,28 +4886,30 @@ netdev_features_t netif_skb_features(struct sk_buff *skb);

static inline bool net_gso_ok(netdev_features_t features, int gso_type) { +#define GSO_INDEX(x) ((1ULL << (x)) >> NETIF_F_GSO_SHIFT)

What if we get a new GSO offload which's corresponding bit will be higher than 64? You could instead do

#define __SKB_GSO_FLAG(x) (1ULL << (x))

enum { SKB_GSO_TCPV4_BIT = 0, SKB_GSO_DODGY_BIT = 1, ..., }; enum { SKB_GSO_TCPV4 = __SKB_GSO_FLAG(TCPV4), SKB_GSO_DODGY = __SKB_GSO_FLAG(DODGY), ..., };

and then just

#define ASSERT_GSO_TYPE(fl, feat) \ static_assert((fl) == (feat) - NETIF_F_GSO_SHIFT)

... ASSERT_GSO_TYPE(SKB_GSO_TCPV4_BIT, NETIF_F_TSO_BIT); ASSERT_GSO_TYPE(SKB_GSO_DODGY, NETIF_F_GSO_ROBUST_BIT); ...

Yes, it may be misused for new GSO offload bit higher than 64, the macro __SKB_GSO_FLAG(x) is better.

...

• netdev_features_t feature = (netdev_features_t)gso_type << NETIF_F_GSO_SHIFT;

  /* check flags correspondence */

• BUILD_BUG_ON(SKB_GSO_TCPV4 != (NETIF_F_TSO >> NETIF_F_GSO_SHIFT));
• BUILD_BUG_ON(SKB_GSO_DODGY != (NETIF_F_GSO_ROBUST >> NETIF_F_GSO_SHIFT));
• BUILD_BUG_ON(SKB_GSO_TCP_ECN != (NETIF_F_TSO_ECN >> NETIF_F_GSO_SHIFT));
• BUILD_BUG_ON(SKB_GSO_TCP_FIXEDID != (NETIF_F_TSO_MANGLEID >> NETIF_F_GSO_SHIFT));
• BUILD_BUG_ON(SKB_GSO_TCPV6 != (NETIF_F_TSO6 >> NETIF_F_GSO_SHIFT));
• BUILD_BUG_ON(SKB_GSO_FCOE != (NETIF_F_FSO >> NETIF_F_GSO_SHIFT));
• BUILD_BUG_ON(SKB_GSO_GRE != (NETIF_F_GSO_GRE >> NETIF_F_GSO_SHIFT));
• BUILD_BUG_ON(SKB_GSO_GRE_CSUM != (NETIF_F_GSO_GRE_CSUM >> NETIF_F_GSO_SHIFT));
• BUILD_BUG_ON(SKB_GSO_IPXIP4 != (NETIF_F_GSO_IPXIP4 >> NETIF_F_GSO_SHIFT));
• BUILD_BUG_ON(SKB_GSO_IPXIP6 != (NETIF_F_GSO_IPXIP6 >> NETIF_F_GSO_SHIFT));
• BUILD_BUG_ON(SKB_GSO_UDP_TUNNEL != (NETIF_F_GSO_UDP_TUNNEL >> NETIF_F_GSO_SHIFT));
• BUILD_BUG_ON(SKB_GSO_UDP_TUNNEL_CSUM != (NETIF_F_GSO_UDP_TUNNEL_CSUM >> NETIF_F_GSO_SHIFT));
• BUILD_BUG_ON(SKB_GSO_PARTIAL != (NETIF_F_GSO_PARTIAL >> NETIF_F_GSO_SHIFT));
• BUILD_BUG_ON(SKB_GSO_TUNNEL_REMCSUM != (NETIF_F_GSO_TUNNEL_REMCSUM >> NETIF_F_GSO_SHIFT));
• BUILD_BUG_ON(SKB_GSO_SCTP != (NETIF_F_GSO_SCTP >> NETIF_F_GSO_SHIFT));
• BUILD_BUG_ON(SKB_GSO_ESP != (NETIF_F_GSO_ESP >> NETIF_F_GSO_SHIFT));
• BUILD_BUG_ON(SKB_GSO_UDP != (NETIF_F_GSO_UDP >> NETIF_F_GSO_SHIFT));
• BUILD_BUG_ON(SKB_GSO_UDP_L4 != (NETIF_F_GSO_UDP_L4 >> NETIF_F_GSO_SHIFT));
• BUILD_BUG_ON(SKB_GSO_FRAGLIST != (NETIF_F_GSO_FRAGLIST >> NETIF_F_GSO_SHIFT));

• BUILD_BUG_ON(SKB_GSO_TCPV4 != GSO_INDEX(NETIF_F_TSO_BIT));

• BUILD_BUG_ON(SKB_GSO_DODGY != GSO_INDEX(NETIF_F_GSO_ROBUST_BIT));

• BUILD_BUG_ON(SKB_GSO_TCP_ECN != GSO_INDEX(NETIF_F_TSO_ECN_BIT));

• BUILD_BUG_ON(SKB_GSO_TCP_FIXEDID != GSO_INDEX(NETIF_F_TSO_MANGLEID_BIT));

• BUILD_BUG_ON(SKB_GSO_TCPV6 != GSO_INDEX(NETIF_F_TSO6_BIT));

• BUILD_BUG_ON(SKB_GSO_FCOE != GSO_INDEX(NETIF_F_FSO_BIT));

• BUILD_BUG_ON(SKB_GSO_GRE != GSO_INDEX(NETIF_F_GSO_GRE_BIT));

• BUILD_BUG_ON(SKB_GSO_GRE_CSUM != GSO_INDEX(NETIF_F_GSO_GRE_CSUM_BIT));

• BUILD_BUG_ON(SKB_GSO_IPXIP4 != GSO_INDEX(NETIF_F_GSO_IPXIP4_BIT));

• BUILD_BUG_ON(SKB_GSO_IPXIP6 != GSO_INDEX(NETIF_F_GSO_IPXIP6_BIT));

• BUILD_BUG_ON(SKB_GSO_UDP_TUNNEL != GSO_INDEX(NETIF_F_GSO_UDP_TUNNEL_BIT));

• BUILD_BUG_ON(SKB_GSO_UDP_TUNNEL_CSUM != GSO_INDEX(NETIF_F_GSO_UDP_TUNNEL_CSUM_BIT));

• BUILD_BUG_ON(SKB_GSO_PARTIAL != GSO_INDEX(NETIF_F_GSO_PARTIAL_BIT));

• BUILD_BUG_ON(SKB_GSO_TUNNEL_REMCSUM != GSO_INDEX(NETIF_F_GSO_TUNNEL_REMCSUM_BIT));

• BUILD_BUG_ON(SKB_GSO_SCTP != GSO_INDEX(NETIF_F_GSO_SCTP_BIT));

• BUILD_BUG_ON(SKB_GSO_ESP != GSO_INDEX(NETIF_F_GSO_ESP_BIT));

• BUILD_BUG_ON(SKB_GSO_UDP != GSO_INDEX(NETIF_F_GSO_UDP_BIT));

• BUILD_BUG_ON(SKB_GSO_UDP_L4 != GSO_INDEX(NETIF_F_GSO_UDP_L4_BIT));

• BUILD_BUG_ON(SKB_GSO_FRAGLIST != GSO_INDEX(NETIF_F_GSO_FRAGLIST_BIT));

  return (features & feature) == feature; }

-- 2.33.0

Thanks, Olek .