freebsd-skq/sys/netinet/in_rss.c
Adrian Chadd b2bdc62a95 Refactor / restructure the RSS code into generic, IPv4 and IPv6 specific
bits.

The motivation here is to eventually teach netisr and potentially
other networking subsystems a bit more about how RSS work queues / buckets
are configured so things have a hope of auto-configuring in the future.

* net/rss_config.[ch] takes care of the generic bits for doing
  configuration, hash function selection, etc;
* topelitz.[ch] is now in net/ rather than netinet/;
* (and would be in libkern if it didn't directly include RSS_KEYSIZE;
  that's a later thing to fix up.)
* netinet/in_rss.[ch] now just contains the IPv4 specific methods;
* and netinet/in6_rss.[ch] now just contains the IPv6 specific methods.

This should have no functional impact on anyone currently using
the RSS support.

Differential Revision:	D1383
Reviewed by:	gnn, jfv (intel driver bits)
2015-01-18 18:06:40 +00:00

358 lines
10 KiB
C

/*-
* Copyright (c) 2010-2011 Juniper Networks, Inc.
* All rights reserved.
*
* This software was developed by Robert N. M. Watson under contract
* to Juniper Networks, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_inet6.h"
#include "opt_pcbgroup.h"
#ifndef PCBGROUP
#error "options RSS depends on options PCBGROUP"
#endif
#include <sys/param.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/priv.h>
#include <sys/kernel.h>
#include <sys/smp.h>
#include <sys/sysctl.h>
#include <sys/sbuf.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/netisr.h>
#include <net/rss_config.h>
#include <netinet/in.h>
#include <netinet/in_pcb.h>
#include <netinet/in_rss.h>
#include <netinet/in_var.h>
/* for software rss hash support */
#include <netinet/ip.h>
#include <netinet/tcp.h>
#include <netinet/udp.h>
/*
* Hash an IPv4 2-tuple.
*/
uint32_t
rss_hash_ip4_2tuple(struct in_addr src, struct in_addr dst)
{
uint8_t data[sizeof(src) + sizeof(dst)];
u_int datalen;
datalen = 0;
bcopy(&src, &data[datalen], sizeof(src));
datalen += sizeof(src);
bcopy(&dst, &data[datalen], sizeof(dst));
datalen += sizeof(dst);
return (rss_hash(datalen, data));
}
/*
* Hash an IPv4 4-tuple.
*/
uint32_t
rss_hash_ip4_4tuple(struct in_addr src, u_short srcport, struct in_addr dst,
u_short dstport)
{
uint8_t data[sizeof(src) + sizeof(dst) + sizeof(srcport) +
sizeof(dstport)];
u_int datalen;
datalen = 0;
bcopy(&src, &data[datalen], sizeof(src));
datalen += sizeof(src);
bcopy(&dst, &data[datalen], sizeof(dst));
datalen += sizeof(dst);
bcopy(&srcport, &data[datalen], sizeof(srcport));
datalen += sizeof(srcport);
bcopy(&dstport, &data[datalen], sizeof(dstport));
datalen += sizeof(dstport);
return (rss_hash(datalen, data));
}
/*
* Calculate an appropriate ipv4 2-tuple or 4-tuple given the given
* IPv4 source/destination address, UDP or TCP source/destination ports
* and the protocol type.
*
* The protocol code may wish to do a software hash of the given
* tuple. This depends upon the currently configured RSS hash types.
*
* This assumes that the packet in question isn't a fragment.
*
* It also assumes the packet source/destination address
* are in "incoming" packet order (ie, source is "far" address.)
*/
int
rss_proto_software_hash_v4(struct in_addr s, struct in_addr d,
u_short sp, u_short dp, int proto,
uint32_t *hashval, uint32_t *hashtype)
{
uint32_t hash;
/*
* Next, choose the hash type depending upon the protocol
* identifier.
*/
if ((proto == IPPROTO_TCP) &&
(rss_gethashconfig() & RSS_HASHTYPE_RSS_TCP_IPV4)) {
hash = rss_hash_ip4_4tuple(s, sp, d, dp);
*hashval = hash;
*hashtype = M_HASHTYPE_RSS_TCP_IPV4;
return (0);
} else if ((proto == IPPROTO_UDP) &&
(rss_gethashconfig() & RSS_HASHTYPE_RSS_UDP_IPV4)) {
hash = rss_hash_ip4_4tuple(s, sp, d, dp);
*hashval = hash;
*hashtype = M_HASHTYPE_RSS_UDP_IPV4;
return (0);
} else if (rss_gethashconfig() & RSS_HASHTYPE_RSS_IPV4) {
/* RSS doesn't hash on other protocols like SCTP; so 2-tuple */
hash = rss_hash_ip4_2tuple(s, d);
*hashval = hash;
*hashtype = M_HASHTYPE_RSS_IPV4;
return (0);
}
/* No configured available hashtypes! */
printf("%s: no available hashtypes!\n", __func__);
return (-1);
}
/*
* Do a software calculation of the RSS for the given mbuf.
*
* This is typically used by the input path to recalculate the RSS after
* some form of packet processing (eg de-capsulation, IP fragment reassembly.)
*
* dir is the packet direction - RSS_HASH_PKT_INGRESS for incoming and
* RSS_HASH_PKT_EGRESS for outgoing.
*
* Returns 0 if a hash was done, -1 if no hash was done, +1 if
* the mbuf already had a valid RSS flowid.
*
* This function doesn't modify the mbuf. It's up to the caller to
* assign flowid/flowtype as appropriate.
*/
int
rss_mbuf_software_hash_v4(const struct mbuf *m, int dir, uint32_t *hashval,
uint32_t *hashtype)
{
const struct ip *ip;
const struct tcphdr *th;
const struct udphdr *uh;
uint32_t flowid;
uint32_t flowtype;
uint8_t proto;
int iphlen;
int is_frag = 0;
/*
* XXX For now this only handles hashing on incoming mbufs.
*/
if (dir != RSS_HASH_PKT_INGRESS) {
printf("%s: called on EGRESS packet!\n", __func__);
return (-1);
}
/*
* First, validate that the mbuf we have is long enough
* to have an IPv4 header in it.
*/
if (m->m_pkthdr.len < (sizeof(struct ip))) {
printf("%s: short mbuf pkthdr\n", __func__);
return (-1);
}
if (m->m_len < (sizeof(struct ip))) {
printf("%s: short mbuf len\n", __func__);
return (-1);
}
/* Ok, let's dereference that */
ip = mtod(m, struct ip *);
proto = ip->ip_p;
iphlen = ip->ip_hl << 2;
/*
* If this is a fragment then it shouldn't be four-tuple
* hashed just yet. Once it's reassembled into a full
* frame it should be re-hashed.
*/
if (ip->ip_off & htons(IP_MF | IP_OFFMASK))
is_frag = 1;
/*
* If the mbuf flowid/flowtype matches the packet type,
* and we don't support the 4-tuple version of the given protocol,
* then signal to the owner that it can trust the flowid/flowtype
* details.
*
* This is a little picky - eg, if TCPv4 / UDPv4 hashing
* is supported but we got a TCP/UDP frame only 2-tuple hashed,
* then we shouldn't just "trust" the 2-tuple hash. We need
* a 4-tuple hash.
*/
flowid = m->m_pkthdr.flowid;
flowtype = M_HASHTYPE_GET(m);
if (flowtype != M_HASHTYPE_NONE) {
switch (proto) {
case IPPROTO_UDP:
if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_UDP_IPV4) &&
(flowtype == M_HASHTYPE_RSS_UDP_IPV4) &&
(is_frag == 0)) {
return (1);
}
/*
* Only allow 2-tuple for UDP frames if we don't also
* support 4-tuple for UDP.
*/
if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_IPV4) &&
((rss_gethashconfig() & RSS_HASHTYPE_RSS_UDP_IPV4) == 0) &&
flowtype == M_HASHTYPE_RSS_IPV4) {
return (1);
}
break;
case IPPROTO_TCP:
if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_TCP_IPV4) &&
(flowtype == M_HASHTYPE_RSS_TCP_IPV4) &&
(is_frag == 0)) {
return (1);
}
/*
* Only allow 2-tuple for TCP frames if we don't also
* support 2-tuple for TCP.
*/
if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_IPV4) &&
((rss_gethashconfig() & RSS_HASHTYPE_RSS_TCP_IPV4) == 0) &&
flowtype == M_HASHTYPE_RSS_IPV4) {
return (1);
}
break;
default:
if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_IPV4) &&
flowtype == M_HASHTYPE_RSS_IPV4) {
return (1);
}
break;
}
}
/*
* Decode enough information to make a hash decision.
*
* XXX TODO: does the hardware hash on 4-tuple if IP
* options are present?
*/
if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_TCP_IPV4) &&
(proto == IPPROTO_TCP) &&
(is_frag == 0)) {
if (m->m_len < iphlen + sizeof(struct tcphdr)) {
printf("%s: short TCP frame?\n", __func__);
return (-1);
}
th = (struct tcphdr *)((caddr_t)ip + iphlen);
return rss_proto_software_hash_v4(ip->ip_src, ip->ip_dst,
th->th_sport,
th->th_dport,
proto,
hashval,
hashtype);
} else if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_UDP_IPV4) &&
(proto == IPPROTO_UDP) &&
(is_frag == 0)) {
uh = (struct udphdr *)((caddr_t)ip + iphlen);
if (m->m_len < iphlen + sizeof(struct udphdr)) {
printf("%s: short UDP frame?\n", __func__);
return (-1);
}
return rss_proto_software_hash_v4(ip->ip_src, ip->ip_dst,
uh->uh_sport,
uh->uh_dport,
proto,
hashval,
hashtype);
} else if (rss_gethashconfig() & RSS_HASHTYPE_RSS_IPV4) {
/* Default to 2-tuple hash */
return rss_proto_software_hash_v4(ip->ip_src, ip->ip_dst,
0, /* source port */
0, /* destination port */
0, /* IPPROTO_IP */
hashval,
hashtype);
} else {
printf("%s: no available hashtypes!\n", __func__);
return (-1);
}
}
/*
* Similar to rss_m2cpuid, but designed to be used by the IP NETISR
* on incoming frames.
*
* If an existing RSS hash exists and it matches what the configured
* hashing is, then use it.
*
* If there's an existing RSS hash but the desired hash is different,
* or if there's no useful RSS hash, then calculate it via
* the software path.
*
* XXX TODO: definitely want statistics here!
*/
struct mbuf *
rss_soft_m2cpuid(struct mbuf *m, uintptr_t source, u_int *cpuid)
{
uint32_t hash_val, hash_type;
int ret;
M_ASSERTPKTHDR(m);
ret = rss_mbuf_software_hash_v4(m, RSS_HASH_PKT_INGRESS,
&hash_val, &hash_type);
if (ret > 0) {
/* mbuf has a valid hash already; don't need to modify it */
*cpuid = rss_hash2cpuid(m->m_pkthdr.flowid, M_HASHTYPE_GET(m));
} else if (ret == 0) {
/* hash was done; update */
m->m_pkthdr.flowid = hash_val;
M_HASHTYPE_SET(m, hash_type);
*cpuid = rss_hash2cpuid(m->m_pkthdr.flowid, M_HASHTYPE_GET(m));
} else { /* ret < 0 */
/* no hash was done */
*cpuid = NETISR_CPUID_NONE;
}
return (m);
}