lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Message-Id: <1271772160-28177-1-git-send-email-xiaosuo@gmail.com> Date: Tue, 20 Apr 2010 22:02:40 +0800 From: Changli Gao <xiaosuo@...il.com> To: "David S. Miller" <davem@...emloft.net> Cc: Tom Herbert <therbert@...gle.com>, Eric Dumazet <eric.dumazet@...il.com>, netdev@...r.kernel.org, Changli Gao <xiaosuo@...il.com> Subject: [PATCH v2] rps: optimize rps_get_cpu() optimize rps_get_cpu(). don't initialize ports when we can get the ports. one memory access for ports than two. use ihl in bytes to eliminate later multiplyings. Signed-off-by: Changli Gao <xiaosuo@...il.com> ---- net/core/dev.c | 30 ++++++++++++++---------------- 1 file changed, 14 insertions(+), 16 deletions(-) diff --git a/net/core/dev.c b/net/core/dev.c index b31d5d6..55ecfa9 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2225,7 +2225,11 @@ static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, int cpu = -1; u8 ip_proto; u16 tcpu; - u32 addr1, addr2, ports, ihl; + u32 addr1, addr2, ihl; + union { + u32 v32; + u16 v16[2]; + } ports; if (skb_rx_queue_recorded(skb)) { u16 index = skb_get_rx_queue(skb); @@ -2256,7 +2260,7 @@ static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, ip_proto = ip->protocol; addr1 = (__force u32) ip->saddr; addr2 = (__force u32) ip->daddr; - ihl = ip->ihl; + ihl = ip->ihl << 2; break; case __constant_htons(ETH_P_IPV6): if (!pskb_may_pull(skb, sizeof(*ip6))) @@ -2266,12 +2270,11 @@ static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, ip_proto = ip6->nexthdr; addr1 = (__force u32) ip6->saddr.s6_addr32[3]; addr2 = (__force u32) ip6->daddr.s6_addr32[3]; - ihl = (40 >> 2); + ihl = 40; break; default: goto done; } - ports = 0; switch (ip_proto) { case IPPROTO_TCP: case IPPROTO_UDP: @@ -2280,26 +2283,21 @@ static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, case IPPROTO_AH: case IPPROTO_SCTP: case IPPROTO_UDPLITE: - if (pskb_may_pull(skb, (ihl * 4) + 4)) { - __be16 *hports = (__be16 *) (skb->data + (ihl * 4)); - u32 sport, dport; - - sport = (__force u16) hports[0]; - dport = (__force u16) hports[1]; - if (dport < sport) - swap(sport, dport); - ports = (sport << 16) + dport; + if (pskb_may_pull(skb, ihl + 4)) { + ports.v32 = * (__force u32 *) (skb->data + ihl); + if (ports.v16[0] < ports.v16[1]) + swap(ports.v16[0], ports.v16[1]); + break; } - break; - default: + ports.v32 = 0; break; } /* get a consistent hash (same value on both flow directions) */ if (addr2 < addr1) swap(addr1, addr2); - skb->rxhash = jhash_3words(addr1, addr2, ports, hashrnd); + skb->rxhash = jhash_3words(addr1, addr2, ports.v32, hashrnd); if (!skb->rxhash) skb->rxhash = 1; -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists