tcp_hostcache.c revision 172467
1139823Simp/*- 2122922Sandre * Copyright (c) 2002 Andre Oppermann, Internet Business Solutions AG 3122922Sandre * All rights reserved. 4122922Sandre * 5122922Sandre * Redistribution and use in source and binary forms, with or without 6122922Sandre * modification, are permitted provided that the following conditions 7122922Sandre * are met: 8122922Sandre * 1. Redistributions of source code must retain the above copyright 9122922Sandre * notice, this list of conditions and the following disclaimer. 10122922Sandre * 2. Redistributions in binary form must reproduce the above copyright 11122922Sandre * notice, this list of conditions and the following disclaimer in the 12122922Sandre * documentation and/or other materials provided with the distribution. 13122922Sandre * 3. The name of the author may not be used to endorse or promote 14122922Sandre * products derived from this software without specific prior written 15122922Sandre * permission. 16122922Sandre * 17122922Sandre * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18122922Sandre * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19122922Sandre * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20122922Sandre * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21122922Sandre * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22122922Sandre * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23122922Sandre * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24122922Sandre * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25122922Sandre * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26122922Sandre * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27122922Sandre * SUCH DAMAGE. 28122922Sandre */ 29122922Sandre 30122922Sandre/* 31170030Srwatson * The tcp_hostcache moves the tcp-specific cached metrics from the routing 32170030Srwatson * table to a dedicated structure indexed by the remote IP address. It keeps 33170030Srwatson * information on the measured TCP parameters of past TCP sessions to allow 34170030Srwatson * better initial start values to be used with later connections to/from the 35170030Srwatson * same source. Depending on the network parameters (delay, bandwidth, max 36170030Srwatson * MTU, congestion window) between local and remote sites, this can lead to 37170030Srwatson * significant speed-ups for new TCP connections after the first one. 38122922Sandre * 39170030Srwatson * Due to the tcp_hostcache, all TCP-specific metrics information in the 40170030Srwatson * routing table has been removed. The inpcb no longer keeps a pointer to 41170030Srwatson * the routing entry, and protocol-initiated route cloning has been removed 42170030Srwatson * as well. With these changes, the routing table has gone back to being 43170030Srwatson * more lightwight and only carries information related to packet forwarding. 44122922Sandre * 45170030Srwatson * tcp_hostcache is designed for multiple concurrent access in SMP 46170030Srwatson * environments and high contention. All bucket rows have their own lock and 47170030Srwatson * thus multiple lookups and modifies can be done at the same time as long as 48170030Srwatson * they are in different bucket rows. If a request for insertion of a new 49170030Srwatson * record can't be satisfied, it simply returns an empty structure. Nobody 50170030Srwatson * and nothing outside of tcp_hostcache.c will ever point directly to any 51170030Srwatson * entry in the tcp_hostcache. All communication is done in an 52170030Srwatson * object-oriented way and only functions of tcp_hostcache will manipulate 53170030Srwatson * hostcache entries. Otherwise, we are unable to achieve good behaviour in 54170030Srwatson * concurrent access situations. Since tcp_hostcache is only caching 55170030Srwatson * information, there are no fatal consequences if we either can't satisfy 56170030Srwatson * any particular request or have to drop/overwrite an existing entry because 57170030Srwatson * of bucket limit memory constrains. 58122922Sandre */ 59122922Sandre 60122922Sandre/* 61122922Sandre * Many thanks to jlemon for basic structure of tcp_syncache which is being 62122922Sandre * followed here. 63122922Sandre */ 64122922Sandre 65172467Ssilby#include <sys/cdefs.h> 66172467Ssilby__FBSDID("$FreeBSD: head/sys/netinet/tcp_hostcache.c 172467 2007-10-07 20:44:24Z silby $"); 67172467Ssilby 68122922Sandre#include "opt_inet6.h" 69122922Sandre 70122922Sandre#include <sys/param.h> 71122922Sandre#include <sys/systm.h> 72122922Sandre#include <sys/kernel.h> 73122922Sandre#include <sys/lock.h> 74122922Sandre#include <sys/mutex.h> 75122922Sandre#include <sys/malloc.h> 76122922Sandre#include <sys/socket.h> 77122922Sandre#include <sys/socketvar.h> 78122922Sandre#include <sys/sysctl.h> 79122922Sandre 80122922Sandre#include <net/if.h> 81122922Sandre 82122922Sandre#include <netinet/in.h> 83122922Sandre#include <netinet/in_systm.h> 84122922Sandre#include <netinet/ip.h> 85122922Sandre#include <netinet/in_var.h> 86122922Sandre#include <netinet/in_pcb.h> 87122922Sandre#include <netinet/ip_var.h> 88122922Sandre#ifdef INET6 89122922Sandre#include <netinet/ip6.h> 90122922Sandre#include <netinet6/ip6_var.h> 91122922Sandre#endif 92122922Sandre#include <netinet/tcp.h> 93122922Sandre#include <netinet/tcp_var.h> 94122922Sandre#ifdef INET6 95122922Sandre#include <netinet6/tcp6_var.h> 96122922Sandre#endif 97122922Sandre 98122922Sandre#include <vm/uma.h> 99122922Sandre 100122922Sandre 101122922SandreTAILQ_HEAD(hc_qhead, hc_metrics); 102122922Sandre 103122922Sandrestruct hc_head { 104122922Sandre struct hc_qhead hch_bucket; 105122922Sandre u_int hch_length; 106122922Sandre struct mtx hch_mtx; 107122922Sandre}; 108122922Sandre 109122922Sandrestruct hc_metrics { 110122922Sandre /* housekeeping */ 111122922Sandre TAILQ_ENTRY(hc_metrics) rmx_q; 112122922Sandre struct hc_head *rmx_head; /* head of bucket tail queue */ 113122922Sandre struct in_addr ip4; /* IP address */ 114122922Sandre struct in6_addr ip6; /* IP6 address */ 115170030Srwatson /* endpoint specific values for TCP */ 116122922Sandre u_long rmx_mtu; /* MTU for this path */ 117122922Sandre u_long rmx_ssthresh; /* outbound gateway buffer limit */ 118122922Sandre u_long rmx_rtt; /* estimated round trip time */ 119122922Sandre u_long rmx_rttvar; /* estimated rtt variance */ 120122922Sandre u_long rmx_bandwidth; /* estimated bandwidth */ 121122922Sandre u_long rmx_cwnd; /* congestion window */ 122122922Sandre u_long rmx_sendpipe; /* outbound delay-bandwidth product */ 123122922Sandre u_long rmx_recvpipe; /* inbound delay-bandwidth product */ 124170030Srwatson /* TCP hostcache internal data */ 125122922Sandre int rmx_expire; /* lifetime for object */ 126122922Sandre u_long rmx_hits; /* number of hits */ 127122922Sandre u_long rmx_updates; /* number of updates */ 128122922Sandre}; 129122922Sandre 130122922Sandre/* Arbitrary values */ 131122922Sandre#define TCP_HOSTCACHE_HASHSIZE 512 132122922Sandre#define TCP_HOSTCACHE_BUCKETLIMIT 30 133122922Sandre#define TCP_HOSTCACHE_EXPIRE 60*60 /* one hour */ 134122922Sandre#define TCP_HOSTCACHE_PRUNE 5*60 /* every 5 minutes */ 135122922Sandre 136122922Sandrestruct tcp_hostcache { 137122922Sandre struct hc_head *hashbase; 138122922Sandre uma_zone_t zone; 139122922Sandre u_int hashsize; 140122922Sandre u_int hashmask; 141122922Sandre u_int bucket_limit; 142122922Sandre u_int cache_count; 143122922Sandre u_int cache_limit; 144122922Sandre int expire; 145170434Syar int prune; 146122922Sandre int purgeall; 147122922Sandre}; 148122922Sandrestatic struct tcp_hostcache tcp_hostcache; 149122922Sandre 150122922Sandrestatic struct callout tcp_hc_callout; 151122922Sandre 152122922Sandrestatic struct hc_metrics *tcp_hc_lookup(struct in_conninfo *); 153122922Sandrestatic struct hc_metrics *tcp_hc_insert(struct in_conninfo *); 154122922Sandrestatic int sysctl_tcp_hc_list(SYSCTL_HANDLER_ARGS); 155122922Sandrestatic void tcp_hc_purge(void *); 156122922Sandre 157122922SandreSYSCTL_NODE(_net_inet_tcp, OID_AUTO, hostcache, CTLFLAG_RW, 0, "TCP Host cache"); 158122922Sandre 159122922SandreSYSCTL_INT(_net_inet_tcp_hostcache, OID_AUTO, cachelimit, CTLFLAG_RDTUN, 160167784Sandre &tcp_hostcache.cache_limit, 0, "Overall entry limit for hostcache"); 161122922Sandre 162122922SandreSYSCTL_INT(_net_inet_tcp_hostcache, OID_AUTO, hashsize, CTLFLAG_RDTUN, 163167784Sandre &tcp_hostcache.hashsize, 0, "Size of TCP hostcache hashtable"); 164122922Sandre 165122922SandreSYSCTL_INT(_net_inet_tcp_hostcache, OID_AUTO, bucketlimit, CTLFLAG_RDTUN, 166167784Sandre &tcp_hostcache.bucket_limit, 0, "Per-bucket hash limit for hostcache"); 167122922Sandre 168122922SandreSYSCTL_INT(_net_inet_tcp_hostcache, OID_AUTO, count, CTLFLAG_RD, 169167784Sandre &tcp_hostcache.cache_count, 0, "Current number of entries in hostcache"); 170122922Sandre 171122922SandreSYSCTL_INT(_net_inet_tcp_hostcache, OID_AUTO, expire, CTLFLAG_RW, 172167784Sandre &tcp_hostcache.expire, 0, "Expire time of TCP hostcache entries"); 173122922Sandre 174170434SyarSYSCTL_INT(_net_inet_tcp_hostcache, OID_AUTO, prune, CTLFLAG_RW, 175170434Syar &tcp_hostcache.prune, 0, "Time between purge runs"); 176170434Syar 177122922SandreSYSCTL_INT(_net_inet_tcp_hostcache, OID_AUTO, purge, CTLFLAG_RW, 178167784Sandre &tcp_hostcache.purgeall, 0, "Expire all entires on next purge run"); 179122922Sandre 180122922SandreSYSCTL_PROC(_net_inet_tcp_hostcache, OID_AUTO, list, 181167784Sandre CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_SKIP, 0, 0, 182167784Sandre sysctl_tcp_hc_list, "A", "List of all hostcache entries"); 183122922Sandre 184122922Sandre 185122922Sandrestatic MALLOC_DEFINE(M_HOSTCACHE, "hostcache", "TCP hostcache"); 186122922Sandre 187122922Sandre#define HOSTCACHE_HASH(ip) \ 188133874Srwatson (((ip)->s_addr ^ ((ip)->s_addr >> 7) ^ ((ip)->s_addr >> 17)) & \ 189122922Sandre tcp_hostcache.hashmask) 190122922Sandre 191122922Sandre/* XXX: What is the recommended hash to get good entropy for IPv6 addresses? */ 192133874Srwatson#define HOSTCACHE_HASH6(ip6) \ 193122922Sandre (((ip6)->s6_addr32[0] ^ \ 194122922Sandre (ip6)->s6_addr32[1] ^ \ 195122922Sandre (ip6)->s6_addr32[2] ^ \ 196122922Sandre (ip6)->s6_addr32[3]) & \ 197122922Sandre tcp_hostcache.hashmask) 198122922Sandre 199122922Sandre#define THC_LOCK(lp) mtx_lock(lp) 200122922Sandre#define THC_UNLOCK(lp) mtx_unlock(lp) 201122922Sandre 202122922Sandrevoid 203122922Sandretcp_hc_init(void) 204122922Sandre{ 205122922Sandre int i; 206122922Sandre 207122922Sandre /* 208170030Srwatson * Initialize hostcache structures. 209122922Sandre */ 210122922Sandre tcp_hostcache.cache_count = 0; 211122922Sandre tcp_hostcache.hashsize = TCP_HOSTCACHE_HASHSIZE; 212122922Sandre tcp_hostcache.bucket_limit = TCP_HOSTCACHE_BUCKETLIMIT; 213122922Sandre tcp_hostcache.cache_limit = 214122922Sandre tcp_hostcache.hashsize * tcp_hostcache.bucket_limit; 215122922Sandre tcp_hostcache.expire = TCP_HOSTCACHE_EXPIRE; 216170434Syar tcp_hostcache.prune = TCP_HOSTCACHE_PRUNE; 217122922Sandre 218133874Srwatson TUNABLE_INT_FETCH("net.inet.tcp.hostcache.hashsize", 219122922Sandre &tcp_hostcache.hashsize); 220133874Srwatson TUNABLE_INT_FETCH("net.inet.tcp.hostcache.cachelimit", 221122922Sandre &tcp_hostcache.cache_limit); 222133874Srwatson TUNABLE_INT_FETCH("net.inet.tcp.hostcache.bucketlimit", 223122922Sandre &tcp_hostcache.bucket_limit); 224122922Sandre if (!powerof2(tcp_hostcache.hashsize)) { 225133874Srwatson printf("WARNING: hostcache hash size is not a power of 2.\n"); 226170435Syar tcp_hostcache.hashsize = TCP_HOSTCACHE_HASHSIZE; /* default */ 227133874Srwatson } 228122922Sandre tcp_hostcache.hashmask = tcp_hostcache.hashsize - 1; 229122922Sandre 230122922Sandre /* 231170030Srwatson * Allocate the hash table. 232122922Sandre */ 233122922Sandre tcp_hostcache.hashbase = (struct hc_head *) 234122922Sandre malloc(tcp_hostcache.hashsize * sizeof(struct hc_head), 235122922Sandre M_HOSTCACHE, M_WAITOK | M_ZERO); 236122922Sandre 237122922Sandre /* 238170030Srwatson * Initialize the hash buckets. 239122922Sandre */ 240122922Sandre for (i = 0; i < tcp_hostcache.hashsize; i++) { 241122922Sandre TAILQ_INIT(&tcp_hostcache.hashbase[i].hch_bucket); 242122922Sandre tcp_hostcache.hashbase[i].hch_length = 0; 243122922Sandre mtx_init(&tcp_hostcache.hashbase[i].hch_mtx, "tcp_hc_entry", 244122922Sandre NULL, MTX_DEF); 245122922Sandre } 246122922Sandre 247122922Sandre /* 248122922Sandre * Allocate the hostcache entries. 249122922Sandre */ 250122922Sandre tcp_hostcache.zone = uma_zcreate("hostcache", sizeof(struct hc_metrics), 251133509Sandre NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 252122922Sandre uma_zone_set_max(tcp_hostcache.zone, tcp_hostcache.cache_limit); 253122922Sandre 254122922Sandre /* 255122922Sandre * Set up periodic cache cleanup. 256122922Sandre */ 257122922Sandre callout_init(&tcp_hc_callout, CALLOUT_MPSAFE); 258170434Syar callout_reset(&tcp_hc_callout, tcp_hostcache.prune * hz, tcp_hc_purge, 0); 259122922Sandre} 260122922Sandre 261122922Sandre/* 262170030Srwatson * Internal function: look up an entry in the hostcache or return NULL. 263122922Sandre * 264122922Sandre * If an entry has been returned, the caller becomes responsible for 265122922Sandre * unlocking the bucket row after he is done reading/modifying the entry. 266122922Sandre */ 267122922Sandrestatic struct hc_metrics * 268122922Sandretcp_hc_lookup(struct in_conninfo *inc) 269122922Sandre{ 270122922Sandre int hash; 271122922Sandre struct hc_head *hc_head; 272122922Sandre struct hc_metrics *hc_entry; 273122922Sandre 274122922Sandre KASSERT(inc != NULL, ("tcp_hc_lookup with NULL in_conninfo pointer")); 275122922Sandre 276122922Sandre /* 277122922Sandre * Hash the foreign ip address. 278122922Sandre */ 279122922Sandre if (inc->inc_isipv6) 280122922Sandre hash = HOSTCACHE_HASH6(&inc->inc6_faddr); 281122922Sandre else 282122922Sandre hash = HOSTCACHE_HASH(&inc->inc_faddr); 283122922Sandre 284122922Sandre hc_head = &tcp_hostcache.hashbase[hash]; 285122922Sandre 286122922Sandre /* 287170030Srwatson * Acquire lock for this bucket row; we release the lock if we don't 288170030Srwatson * find an entry, otherwise the caller has to unlock after he is 289170030Srwatson * done. 290122922Sandre */ 291122922Sandre THC_LOCK(&hc_head->hch_mtx); 292122922Sandre 293122922Sandre /* 294170030Srwatson * Iterate through entries in bucket row looking for a match. 295122922Sandre */ 296122922Sandre TAILQ_FOREACH(hc_entry, &hc_head->hch_bucket, rmx_q) { 297122922Sandre if (inc->inc_isipv6) { 298122922Sandre if (memcmp(&inc->inc6_faddr, &hc_entry->ip6, 299122922Sandre sizeof(inc->inc6_faddr)) == 0) 300122922Sandre return hc_entry; 301122922Sandre } else { 302122922Sandre if (memcmp(&inc->inc_faddr, &hc_entry->ip4, 303122922Sandre sizeof(inc->inc_faddr)) == 0) 304122922Sandre return hc_entry; 305122922Sandre } 306122922Sandre } 307122922Sandre 308122922Sandre /* 309170030Srwatson * We were unsuccessful and didn't find anything. 310122922Sandre */ 311122922Sandre THC_UNLOCK(&hc_head->hch_mtx); 312122922Sandre return NULL; 313122922Sandre} 314122922Sandre 315122922Sandre/* 316170030Srwatson * Internal function: insert an entry into the hostcache or return NULL if 317170030Srwatson * unable to allocate a new one. 318133874Srwatson * 319122922Sandre * If an entry has been returned, the caller becomes responsible for 320122922Sandre * unlocking the bucket row after he is done reading/modifying the entry. 321122922Sandre */ 322122922Sandrestatic struct hc_metrics * 323122922Sandretcp_hc_insert(struct in_conninfo *inc) 324122922Sandre{ 325122922Sandre int hash; 326122922Sandre struct hc_head *hc_head; 327122922Sandre struct hc_metrics *hc_entry; 328122922Sandre 329122922Sandre KASSERT(inc != NULL, ("tcp_hc_insert with NULL in_conninfo pointer")); 330122922Sandre 331122922Sandre /* 332170030Srwatson * Hash the foreign ip address. 333122922Sandre */ 334122922Sandre if (inc->inc_isipv6) 335122922Sandre hash = HOSTCACHE_HASH6(&inc->inc6_faddr); 336122922Sandre else 337122922Sandre hash = HOSTCACHE_HASH(&inc->inc_faddr); 338122922Sandre 339122922Sandre hc_head = &tcp_hostcache.hashbase[hash]; 340122922Sandre 341122922Sandre /* 342170030Srwatson * Acquire lock for this bucket row; we release the lock if we don't 343170030Srwatson * find an entry, otherwise the caller has to unlock after he is 344170030Srwatson * done. 345122922Sandre */ 346122922Sandre THC_LOCK(&hc_head->hch_mtx); 347122922Sandre 348122922Sandre /* 349170030Srwatson * If the bucket limit is reached, reuse the least-used element. 350122922Sandre */ 351122922Sandre if (hc_head->hch_length >= tcp_hostcache.bucket_limit || 352122922Sandre tcp_hostcache.cache_count >= tcp_hostcache.cache_limit) { 353122922Sandre hc_entry = TAILQ_LAST(&hc_head->hch_bucket, hc_qhead); 354122922Sandre /* 355122922Sandre * At first we were dropping the last element, just to 356170030Srwatson * reacquire it in the next two lines again, which isn't very 357170030Srwatson * efficient. Instead just reuse the least used element. 358170030Srwatson * We may drop something that is still "in-use" but we can be 359170030Srwatson * "lossy". 360170405Sandre * Just give up if this bucket row is empty and we don't have 361170405Sandre * anything to replace. 362122922Sandre */ 363170405Sandre if (hc_entry == NULL) { 364170405Sandre THC_UNLOCK(&hc_head->hch_mtx); 365170405Sandre return NULL; 366170405Sandre } 367122922Sandre TAILQ_REMOVE(&hc_head->hch_bucket, hc_entry, rmx_q); 368122922Sandre tcp_hostcache.hashbase[hash].hch_length--; 369122922Sandre tcp_hostcache.cache_count--; 370123028Sandre tcpstat.tcps_hc_bucketoverflow++; 371123028Sandre#if 0 372123028Sandre uma_zfree(tcp_hostcache.zone, hc_entry); 373122922Sandre#endif 374122922Sandre } else { 375122922Sandre /* 376170030Srwatson * Allocate a new entry, or balk if not possible. 377122922Sandre */ 378122922Sandre hc_entry = uma_zalloc(tcp_hostcache.zone, M_NOWAIT); 379122922Sandre if (hc_entry == NULL) { 380122922Sandre THC_UNLOCK(&hc_head->hch_mtx); 381122922Sandre return NULL; 382122922Sandre } 383122922Sandre } 384122922Sandre 385122922Sandre /* 386170030Srwatson * Initialize basic information of hostcache entry. 387122922Sandre */ 388122922Sandre bzero(hc_entry, sizeof(*hc_entry)); 389122922Sandre if (inc->inc_isipv6) 390123113Sandre bcopy(&inc->inc6_faddr, &hc_entry->ip6, sizeof(hc_entry->ip6)); 391122922Sandre else 392122922Sandre hc_entry->ip4 = inc->inc_faddr; 393122922Sandre hc_entry->rmx_head = hc_head; 394122922Sandre hc_entry->rmx_expire = tcp_hostcache.expire; 395122922Sandre 396122922Sandre /* 397170030Srwatson * Put it upfront. 398122922Sandre */ 399122922Sandre TAILQ_INSERT_HEAD(&hc_head->hch_bucket, hc_entry, rmx_q); 400122922Sandre tcp_hostcache.hashbase[hash].hch_length++; 401122922Sandre tcp_hostcache.cache_count++; 402122922Sandre tcpstat.tcps_hc_added++; 403122922Sandre 404122922Sandre return hc_entry; 405122922Sandre} 406122922Sandre 407122922Sandre/* 408170030Srwatson * External function: look up an entry in the hostcache and fill out the 409170030Srwatson * supplied TCP metrics structure. Fills in NULL when no entry was found or 410170030Srwatson * a value is not set. 411122922Sandre */ 412122922Sandrevoid 413122922Sandretcp_hc_get(struct in_conninfo *inc, struct hc_metrics_lite *hc_metrics_lite) 414122922Sandre{ 415122922Sandre struct hc_metrics *hc_entry; 416122922Sandre 417122922Sandre /* 418170030Srwatson * Find the right bucket. 419122922Sandre */ 420122922Sandre hc_entry = tcp_hc_lookup(inc); 421122922Sandre 422122922Sandre /* 423170030Srwatson * If we don't have an existing object. 424122922Sandre */ 425122922Sandre if (hc_entry == NULL) { 426122922Sandre bzero(hc_metrics_lite, sizeof(*hc_metrics_lite)); 427122922Sandre return; 428122922Sandre } 429122922Sandre hc_entry->rmx_hits++; 430122922Sandre hc_entry->rmx_expire = tcp_hostcache.expire; /* start over again */ 431122922Sandre 432122922Sandre hc_metrics_lite->rmx_mtu = hc_entry->rmx_mtu; 433122922Sandre hc_metrics_lite->rmx_ssthresh = hc_entry->rmx_ssthresh; 434122922Sandre hc_metrics_lite->rmx_rtt = hc_entry->rmx_rtt; 435122922Sandre hc_metrics_lite->rmx_rttvar = hc_entry->rmx_rttvar; 436122922Sandre hc_metrics_lite->rmx_bandwidth = hc_entry->rmx_bandwidth; 437122922Sandre hc_metrics_lite->rmx_cwnd = hc_entry->rmx_cwnd; 438122922Sandre hc_metrics_lite->rmx_sendpipe = hc_entry->rmx_sendpipe; 439122922Sandre hc_metrics_lite->rmx_recvpipe = hc_entry->rmx_recvpipe; 440122922Sandre 441122922Sandre /* 442170030Srwatson * Unlock bucket row. 443122922Sandre */ 444122922Sandre THC_UNLOCK(&hc_entry->rmx_head->hch_mtx); 445122922Sandre} 446122922Sandre 447122922Sandre/* 448170030Srwatson * External function: look up an entry in the hostcache and return the 449170030Srwatson * discovered path MTU. Returns NULL if no entry is found or value is not 450138409Srwatson * set. 451122922Sandre */ 452122922Sandreu_long 453122922Sandretcp_hc_getmtu(struct in_conninfo *inc) 454122922Sandre{ 455122922Sandre struct hc_metrics *hc_entry; 456122922Sandre u_long mtu; 457122922Sandre 458122922Sandre hc_entry = tcp_hc_lookup(inc); 459122922Sandre if (hc_entry == NULL) { 460122922Sandre return 0; 461122922Sandre } 462122922Sandre hc_entry->rmx_hits++; 463122922Sandre hc_entry->rmx_expire = tcp_hostcache.expire; /* start over again */ 464122922Sandre 465122922Sandre mtu = hc_entry->rmx_mtu; 466122922Sandre THC_UNLOCK(&hc_entry->rmx_head->hch_mtx); 467122922Sandre return mtu; 468122922Sandre} 469122922Sandre 470122922Sandre/* 471170030Srwatson * External function: update the MTU value of an entry in the hostcache. 472122922Sandre * Creates a new entry if none was found. 473122922Sandre */ 474122922Sandrevoid 475122922Sandretcp_hc_updatemtu(struct in_conninfo *inc, u_long mtu) 476122922Sandre{ 477122922Sandre struct hc_metrics *hc_entry; 478122922Sandre 479122922Sandre /* 480170030Srwatson * Find the right bucket. 481122922Sandre */ 482122922Sandre hc_entry = tcp_hc_lookup(inc); 483122922Sandre 484122922Sandre /* 485170030Srwatson * If we don't have an existing object, try to insert a new one. 486122922Sandre */ 487122922Sandre if (hc_entry == NULL) { 488122922Sandre hc_entry = tcp_hc_insert(inc); 489122922Sandre if (hc_entry == NULL) 490122922Sandre return; 491122922Sandre } 492122922Sandre hc_entry->rmx_updates++; 493122922Sandre hc_entry->rmx_expire = tcp_hostcache.expire; /* start over again */ 494122922Sandre 495122922Sandre hc_entry->rmx_mtu = mtu; 496122922Sandre 497122922Sandre /* 498170030Srwatson * Put it upfront so we find it faster next time. 499122922Sandre */ 500122922Sandre TAILQ_REMOVE(&hc_entry->rmx_head->hch_bucket, hc_entry, rmx_q); 501122922Sandre TAILQ_INSERT_HEAD(&hc_entry->rmx_head->hch_bucket, hc_entry, rmx_q); 502122922Sandre 503122922Sandre /* 504170030Srwatson * Unlock bucket row. 505122922Sandre */ 506122922Sandre THC_UNLOCK(&hc_entry->rmx_head->hch_mtx); 507122922Sandre} 508122922Sandre 509122922Sandre/* 510170030Srwatson * External function: update the TCP metrics of an entry in the hostcache. 511122922Sandre * Creates a new entry if none was found. 512122922Sandre */ 513122922Sandrevoid 514122922Sandretcp_hc_update(struct in_conninfo *inc, struct hc_metrics_lite *hcml) 515122922Sandre{ 516122922Sandre struct hc_metrics *hc_entry; 517122922Sandre 518122922Sandre hc_entry = tcp_hc_lookup(inc); 519122922Sandre if (hc_entry == NULL) { 520122922Sandre hc_entry = tcp_hc_insert(inc); 521122922Sandre if (hc_entry == NULL) 522122922Sandre return; 523122922Sandre } 524122922Sandre hc_entry->rmx_updates++; 525122922Sandre hc_entry->rmx_expire = tcp_hostcache.expire; /* start over again */ 526122922Sandre 527122922Sandre if (hcml->rmx_rtt != 0) { 528122922Sandre if (hc_entry->rmx_rtt == 0) 529122922Sandre hc_entry->rmx_rtt = hcml->rmx_rtt; 530122922Sandre else 531122922Sandre hc_entry->rmx_rtt = 532122922Sandre (hc_entry->rmx_rtt + hcml->rmx_rtt) / 2; 533122922Sandre tcpstat.tcps_cachedrtt++; 534122922Sandre } 535122922Sandre if (hcml->rmx_rttvar != 0) { 536122922Sandre if (hc_entry->rmx_rttvar == 0) 537133874Srwatson hc_entry->rmx_rttvar = hcml->rmx_rttvar; 538122922Sandre else 539122922Sandre hc_entry->rmx_rttvar = 540122922Sandre (hc_entry->rmx_rttvar + hcml->rmx_rttvar) / 2; 541122922Sandre tcpstat.tcps_cachedrttvar++; 542122922Sandre } 543122922Sandre if (hcml->rmx_ssthresh != 0) { 544122922Sandre if (hc_entry->rmx_ssthresh == 0) 545122922Sandre hc_entry->rmx_ssthresh = hcml->rmx_ssthresh; 546122922Sandre else 547122922Sandre hc_entry->rmx_ssthresh = 548122922Sandre (hc_entry->rmx_ssthresh + hcml->rmx_ssthresh) / 2; 549122922Sandre tcpstat.tcps_cachedssthresh++; 550122922Sandre } 551122922Sandre if (hcml->rmx_bandwidth != 0) { 552122922Sandre if (hc_entry->rmx_bandwidth == 0) 553122922Sandre hc_entry->rmx_bandwidth = hcml->rmx_bandwidth; 554122922Sandre else 555122922Sandre hc_entry->rmx_bandwidth = 556122922Sandre (hc_entry->rmx_bandwidth + hcml->rmx_bandwidth) / 2; 557122922Sandre /* tcpstat.tcps_cachedbandwidth++; */ 558122922Sandre } 559122922Sandre if (hcml->rmx_cwnd != 0) { 560122922Sandre if (hc_entry->rmx_cwnd == 0) 561122922Sandre hc_entry->rmx_cwnd = hcml->rmx_cwnd; 562122922Sandre else 563122922Sandre hc_entry->rmx_cwnd = 564122922Sandre (hc_entry->rmx_cwnd + hcml->rmx_cwnd) / 2; 565122922Sandre /* tcpstat.tcps_cachedcwnd++; */ 566122922Sandre } 567122922Sandre if (hcml->rmx_sendpipe != 0) { 568122922Sandre if (hc_entry->rmx_sendpipe == 0) 569122922Sandre hc_entry->rmx_sendpipe = hcml->rmx_sendpipe; 570122922Sandre else 571122922Sandre hc_entry->rmx_sendpipe = 572122922Sandre (hc_entry->rmx_sendpipe + hcml->rmx_sendpipe) /2; 573133874Srwatson /* tcpstat.tcps_cachedsendpipe++; */ 574133874Srwatson } 575122922Sandre if (hcml->rmx_recvpipe != 0) { 576122922Sandre if (hc_entry->rmx_recvpipe == 0) 577122922Sandre hc_entry->rmx_recvpipe = hcml->rmx_recvpipe; 578122922Sandre else 579122922Sandre hc_entry->rmx_recvpipe = 580122922Sandre (hc_entry->rmx_recvpipe + hcml->rmx_recvpipe) /2; 581122922Sandre /* tcpstat.tcps_cachedrecvpipe++; */ 582122922Sandre } 583122922Sandre 584122922Sandre TAILQ_REMOVE(&hc_entry->rmx_head->hch_bucket, hc_entry, rmx_q); 585122922Sandre TAILQ_INSERT_HEAD(&hc_entry->rmx_head->hch_bucket, hc_entry, rmx_q); 586122922Sandre THC_UNLOCK(&hc_entry->rmx_head->hch_mtx); 587122922Sandre} 588122922Sandre 589122922Sandre/* 590122922Sandre * Sysctl function: prints the list and values of all hostcache entries in 591122922Sandre * unsorted order. 592122922Sandre */ 593122922Sandrestatic int 594122922Sandresysctl_tcp_hc_list(SYSCTL_HANDLER_ARGS) 595122922Sandre{ 596122922Sandre int bufsize; 597122922Sandre int linesize = 128; 598122922Sandre char *p, *buf; 599122922Sandre int len, i, error; 600122922Sandre struct hc_metrics *hc_entry; 601165118Sbz#ifdef INET6 602165118Sbz char ip6buf[INET6_ADDRSTRLEN]; 603165118Sbz#endif 604122922Sandre 605122922Sandre bufsize = linesize * (tcp_hostcache.cache_count + 1); 606122922Sandre 607122922Sandre p = buf = (char *)malloc(bufsize, M_TEMP, M_WAITOK|M_ZERO); 608122922Sandre 609122922Sandre len = snprintf(p, linesize, 610122922Sandre "\nIP address MTU SSTRESH RTT RTTVAR BANDWIDTH " 611122922Sandre " CWND SENDPIPE RECVPIPE HITS UPD EXP\n"); 612122922Sandre p += len; 613122922Sandre 614122922Sandre#define msec(u) (((u) + 500) / 1000) 615122922Sandre for (i = 0; i < tcp_hostcache.hashsize; i++) { 616122922Sandre THC_LOCK(&tcp_hostcache.hashbase[i].hch_mtx); 617122922Sandre TAILQ_FOREACH(hc_entry, &tcp_hostcache.hashbase[i].hch_bucket, 618122922Sandre rmx_q) { 619122922Sandre len = snprintf(p, linesize, 620122922Sandre "%-15s %5lu %8lu %6lums %6lums %9lu %8lu %8lu %8lu " 621122922Sandre "%4lu %4lu %4i\n", 622122922Sandre hc_entry->ip4.s_addr ? inet_ntoa(hc_entry->ip4) : 623122922Sandre#ifdef INET6 624165118Sbz ip6_sprintf(ip6buf, &hc_entry->ip6), 625122922Sandre#else 626122922Sandre "IPv6?", 627122922Sandre#endif 628122922Sandre hc_entry->rmx_mtu, 629122922Sandre hc_entry->rmx_ssthresh, 630122922Sandre msec(hc_entry->rmx_rtt * 631122922Sandre (RTM_RTTUNIT / (hz * TCP_RTT_SCALE))), 632122922Sandre msec(hc_entry->rmx_rttvar * 633122922Sandre (RTM_RTTUNIT / (hz * TCP_RTT_SCALE))), 634133477Sandre hc_entry->rmx_bandwidth * 8, 635122922Sandre hc_entry->rmx_cwnd, 636122922Sandre hc_entry->rmx_sendpipe, 637122922Sandre hc_entry->rmx_recvpipe, 638122922Sandre hc_entry->rmx_hits, 639122922Sandre hc_entry->rmx_updates, 640122922Sandre hc_entry->rmx_expire); 641122922Sandre p += len; 642122922Sandre } 643122922Sandre THC_UNLOCK(&tcp_hostcache.hashbase[i].hch_mtx); 644122922Sandre } 645122922Sandre#undef msec 646122922Sandre error = SYSCTL_OUT(req, buf, p - buf); 647122922Sandre free(buf, M_TEMP); 648122922Sandre return(error); 649122922Sandre} 650122922Sandre 651122922Sandre/* 652170030Srwatson * Expire and purge (old|all) entries in the tcp_hostcache. Runs 653170030Srwatson * periodically from the callout. 654122922Sandre */ 655122922Sandrestatic void 656122922Sandretcp_hc_purge(void *arg) 657122922Sandre{ 658128574Sandre struct hc_metrics *hc_entry, *hc_next; 659122922Sandre int all = (intptr_t)arg; 660122922Sandre int i; 661122922Sandre 662122922Sandre if (tcp_hostcache.purgeall) { 663122922Sandre all = 1; 664122922Sandre tcp_hostcache.purgeall = 0; 665122922Sandre } 666122922Sandre 667122922Sandre for (i = 0; i < tcp_hostcache.hashsize; i++) { 668122922Sandre THC_LOCK(&tcp_hostcache.hashbase[i].hch_mtx); 669128574Sandre TAILQ_FOREACH_SAFE(hc_entry, &tcp_hostcache.hashbase[i].hch_bucket, 670128574Sandre rmx_q, hc_next) { 671122922Sandre if (all || hc_entry->rmx_expire <= 0) { 672122922Sandre TAILQ_REMOVE(&tcp_hostcache.hashbase[i].hch_bucket, 673122922Sandre hc_entry, rmx_q); 674122922Sandre uma_zfree(tcp_hostcache.zone, hc_entry); 675122922Sandre tcp_hostcache.hashbase[i].hch_length--; 676122922Sandre tcp_hostcache.cache_count--; 677122922Sandre } else 678170434Syar hc_entry->rmx_expire -= tcp_hostcache.prune; 679122922Sandre } 680122922Sandre THC_UNLOCK(&tcp_hostcache.hashbase[i].hch_mtx); 681122922Sandre } 682170434Syar callout_reset(&tcp_hc_callout, tcp_hostcache.prune * hz, tcp_hc_purge, 0); 683122922Sandre} 684