tcp_hostcache.c revision 139823
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 * $FreeBSD: head/sys/netinet/tcp_hostcache.c 139823 2005-01-07 01:45:51Z imp $ 30122922Sandre */ 31122922Sandre 32122922Sandre/* 33122922Sandre * The tcp_hostcache moves the tcp specific cached metrics from the routing 34122922Sandre * table into a dedicated structure indexed by the remote IP address. It 35122922Sandre * keeps information on the measured tcp parameters of past tcp sessions 36122922Sandre * to have better initial start values for following connections from the 37122922Sandre * same source. Depending on the network parameters (delay, bandwidth, max 38122922Sandre * MTU, congestion window) between local and remote site this can lead to 39122922Sandre * significant speedups for new tcp connections after the first one. 40122922Sandre * 41122922Sandre * Due to this new tcp_hostcache all tcp specific metrics information in 42122922Sandre * the routing table has been removed. The INPCB no longer keeps a pointer 43122922Sandre * to the routing entry and protocol initiated route cloning has been 44122922Sandre * removed as well. With these changes the routing table has gone back 45122922Sandre * to being more lightwight and only carries information related to packet 46122922Sandre * forwarding. 47122922Sandre * 48122922Sandre * Tcp_hostcache is designed for multiple concurrent access in SMP 49122922Sandre * environments and high contention. All bucket rows have their own 50122922Sandre * lock and thus multiple lookups and modifies can be done at the same 51122922Sandre * time as long as they are in different bucket rows. If a request for 52122922Sandre * insertion of a new record can't be satisfied it simply returns an 53122922Sandre * empty structure. Nobody and nothing shall ever point directly to 54122922Sandre * any entry in tcp_hostcache. All communication is done in an object 55122922Sandre * oriented way and only funtions of tcp_hostcache will manipulate hostcache 56122922Sandre * entries. Otherwise we are unable to achieve good behaviour in concurrent 57122922Sandre * access situations. Since tcp_hostcache is only caching information there 58122922Sandre * are no fatal consequences if we either can't satisfy any particular request 59122922Sandre * or have to drop/overwrite an existing entry because of bucket limit 60122922Sandre * memory constrains. 61122922Sandre */ 62122922Sandre 63122922Sandre/* 64122922Sandre * Many thanks to jlemon for basic structure of tcp_syncache which is being 65122922Sandre * followed here. 66122922Sandre */ 67122922Sandre 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 */ 115122922Sandre /* 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 */ 124122922Sandre /* 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; 145122922Sandre int purgeall; 146122922Sandre}; 147122922Sandrestatic struct tcp_hostcache tcp_hostcache; 148122922Sandre 149122922Sandrestatic struct callout tcp_hc_callout; 150122922Sandre 151122922Sandrestatic struct hc_metrics *tcp_hc_lookup(struct in_conninfo *); 152122922Sandrestatic struct hc_metrics *tcp_hc_insert(struct in_conninfo *); 153122922Sandrestatic int sysctl_tcp_hc_list(SYSCTL_HANDLER_ARGS); 154122922Sandrestatic void tcp_hc_purge(void *); 155122922Sandre 156122922SandreSYSCTL_NODE(_net_inet_tcp, OID_AUTO, hostcache, CTLFLAG_RW, 0, "TCP Host cache"); 157122922Sandre 158122922SandreSYSCTL_INT(_net_inet_tcp_hostcache, OID_AUTO, cachelimit, CTLFLAG_RDTUN, 159122922Sandre &tcp_hostcache.cache_limit, 0, "Overall entry limit for hostcache"); 160122922Sandre 161122922SandreSYSCTL_INT(_net_inet_tcp_hostcache, OID_AUTO, hashsize, CTLFLAG_RDTUN, 162122922Sandre &tcp_hostcache.hashsize, 0, "Size of TCP hostcache hashtable"); 163122922Sandre 164122922SandreSYSCTL_INT(_net_inet_tcp_hostcache, OID_AUTO, bucketlimit, CTLFLAG_RDTUN, 165122922Sandre &tcp_hostcache.bucket_limit, 0, "Per-bucket hash limit for hostcache"); 166122922Sandre 167122922SandreSYSCTL_INT(_net_inet_tcp_hostcache, OID_AUTO, count, CTLFLAG_RD, 168122922Sandre &tcp_hostcache.cache_count, 0, "Current number of entries in hostcache"); 169122922Sandre 170122922SandreSYSCTL_INT(_net_inet_tcp_hostcache, OID_AUTO, expire, CTLFLAG_RW, 171122922Sandre &tcp_hostcache.expire, 0, "Expire time of TCP hostcache entries"); 172122922Sandre 173122922SandreSYSCTL_INT(_net_inet_tcp_hostcache, OID_AUTO, purge, CTLFLAG_RW, 174122922Sandre &tcp_hostcache.purgeall, 0, "Expire all entires on next purge run"); 175122922Sandre 176122922SandreSYSCTL_PROC(_net_inet_tcp_hostcache, OID_AUTO, list, 177122922Sandre CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_SKIP, 0, 0, 178122922Sandre sysctl_tcp_hc_list, "A", "List of all hostcache entries"); 179122922Sandre 180122922Sandre 181122922Sandrestatic MALLOC_DEFINE(M_HOSTCACHE, "hostcache", "TCP hostcache"); 182122922Sandre 183122922Sandre#define HOSTCACHE_HASH(ip) \ 184133874Srwatson (((ip)->s_addr ^ ((ip)->s_addr >> 7) ^ ((ip)->s_addr >> 17)) & \ 185122922Sandre tcp_hostcache.hashmask) 186122922Sandre 187122922Sandre/* XXX: What is the recommended hash to get good entropy for IPv6 addresses? */ 188133874Srwatson#define HOSTCACHE_HASH6(ip6) \ 189122922Sandre (((ip6)->s6_addr32[0] ^ \ 190122922Sandre (ip6)->s6_addr32[1] ^ \ 191122922Sandre (ip6)->s6_addr32[2] ^ \ 192122922Sandre (ip6)->s6_addr32[3]) & \ 193122922Sandre tcp_hostcache.hashmask) 194122922Sandre 195122922Sandre#define THC_LOCK(lp) mtx_lock(lp) 196122922Sandre#define THC_UNLOCK(lp) mtx_unlock(lp) 197122922Sandre 198122922Sandrevoid 199122922Sandretcp_hc_init(void) 200122922Sandre{ 201122922Sandre int i; 202122922Sandre 203122922Sandre /* 204122922Sandre * Initialize hostcache structures 205122922Sandre */ 206122922Sandre tcp_hostcache.cache_count = 0; 207122922Sandre tcp_hostcache.hashsize = TCP_HOSTCACHE_HASHSIZE; 208122922Sandre tcp_hostcache.bucket_limit = TCP_HOSTCACHE_BUCKETLIMIT; 209122922Sandre tcp_hostcache.cache_limit = 210122922Sandre tcp_hostcache.hashsize * tcp_hostcache.bucket_limit; 211122922Sandre tcp_hostcache.expire = TCP_HOSTCACHE_EXPIRE; 212122922Sandre 213133874Srwatson TUNABLE_INT_FETCH("net.inet.tcp.hostcache.hashsize", 214122922Sandre &tcp_hostcache.hashsize); 215133874Srwatson TUNABLE_INT_FETCH("net.inet.tcp.hostcache.cachelimit", 216122922Sandre &tcp_hostcache.cache_limit); 217133874Srwatson TUNABLE_INT_FETCH("net.inet.tcp.hostcache.bucketlimit", 218122922Sandre &tcp_hostcache.bucket_limit); 219122922Sandre if (!powerof2(tcp_hostcache.hashsize)) { 220133874Srwatson printf("WARNING: hostcache hash size is not a power of 2.\n"); 221122922Sandre tcp_hostcache.hashsize = 512; /* safe default */ 222133874Srwatson } 223122922Sandre tcp_hostcache.hashmask = tcp_hostcache.hashsize - 1; 224122922Sandre 225122922Sandre /* 226122922Sandre * Allocate the hash table 227122922Sandre */ 228122922Sandre tcp_hostcache.hashbase = (struct hc_head *) 229122922Sandre malloc(tcp_hostcache.hashsize * sizeof(struct hc_head), 230122922Sandre M_HOSTCACHE, M_WAITOK | M_ZERO); 231122922Sandre 232122922Sandre /* 233122922Sandre * Initialize the hash buckets 234122922Sandre */ 235122922Sandre for (i = 0; i < tcp_hostcache.hashsize; i++) { 236122922Sandre TAILQ_INIT(&tcp_hostcache.hashbase[i].hch_bucket); 237122922Sandre tcp_hostcache.hashbase[i].hch_length = 0; 238122922Sandre mtx_init(&tcp_hostcache.hashbase[i].hch_mtx, "tcp_hc_entry", 239122922Sandre NULL, MTX_DEF); 240122922Sandre } 241122922Sandre 242122922Sandre /* 243122922Sandre * Allocate the hostcache entries. 244122922Sandre */ 245122922Sandre tcp_hostcache.zone = uma_zcreate("hostcache", sizeof(struct hc_metrics), 246133509Sandre NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 247122922Sandre uma_zone_set_max(tcp_hostcache.zone, tcp_hostcache.cache_limit); 248122922Sandre 249122922Sandre /* 250122922Sandre * Set up periodic cache cleanup. 251122922Sandre */ 252122922Sandre callout_init(&tcp_hc_callout, CALLOUT_MPSAFE); 253122922Sandre callout_reset(&tcp_hc_callout, TCP_HOSTCACHE_PRUNE * hz, tcp_hc_purge, 0); 254122922Sandre} 255122922Sandre 256122922Sandre/* 257122922Sandre * Internal function: lookup an entry in the hostcache or return NULL. 258122922Sandre * 259122922Sandre * If an entry has been returned, the caller becomes responsible for 260122922Sandre * unlocking the bucket row after he is done reading/modifying the entry. 261122922Sandre */ 262122922Sandrestatic struct hc_metrics * 263122922Sandretcp_hc_lookup(struct in_conninfo *inc) 264122922Sandre{ 265122922Sandre int hash; 266122922Sandre struct hc_head *hc_head; 267122922Sandre struct hc_metrics *hc_entry; 268122922Sandre 269122922Sandre KASSERT(inc != NULL, ("tcp_hc_lookup with NULL in_conninfo pointer")); 270122922Sandre 271122922Sandre /* 272122922Sandre * Hash the foreign ip address. 273122922Sandre */ 274122922Sandre if (inc->inc_isipv6) 275122922Sandre hash = HOSTCACHE_HASH6(&inc->inc6_faddr); 276122922Sandre else 277122922Sandre hash = HOSTCACHE_HASH(&inc->inc_faddr); 278122922Sandre 279122922Sandre hc_head = &tcp_hostcache.hashbase[hash]; 280122922Sandre 281122922Sandre /* 282122922Sandre * aquire lock for this bucket row 283122922Sandre * we release the lock if we don't find an entry, 284122922Sandre * otherwise the caller has to unlock after he is done 285122922Sandre */ 286122922Sandre THC_LOCK(&hc_head->hch_mtx); 287122922Sandre 288122922Sandre /* 289122922Sandre * circle through entries in bucket row looking for a match 290122922Sandre */ 291122922Sandre TAILQ_FOREACH(hc_entry, &hc_head->hch_bucket, rmx_q) { 292122922Sandre if (inc->inc_isipv6) { 293122922Sandre if (memcmp(&inc->inc6_faddr, &hc_entry->ip6, 294122922Sandre sizeof(inc->inc6_faddr)) == 0) 295122922Sandre return hc_entry; 296122922Sandre } else { 297122922Sandre if (memcmp(&inc->inc_faddr, &hc_entry->ip4, 298122922Sandre sizeof(inc->inc_faddr)) == 0) 299122922Sandre return hc_entry; 300122922Sandre } 301122922Sandre } 302122922Sandre 303122922Sandre /* 304122922Sandre * We were unsuccessful and didn't find anything 305122922Sandre */ 306122922Sandre THC_UNLOCK(&hc_head->hch_mtx); 307122922Sandre return NULL; 308122922Sandre} 309122922Sandre 310122922Sandre/* 311122922Sandre * Internal function: insert an entry into the hostcache or return NULL 312122922Sandre * if unable to allocate a new one. 313133874Srwatson * 314122922Sandre * If an entry has been returned, the caller becomes responsible for 315122922Sandre * unlocking the bucket row after he is done reading/modifying the entry. 316122922Sandre */ 317122922Sandrestatic struct hc_metrics * 318122922Sandretcp_hc_insert(struct in_conninfo *inc) 319122922Sandre{ 320122922Sandre int hash; 321122922Sandre struct hc_head *hc_head; 322122922Sandre struct hc_metrics *hc_entry; 323122922Sandre 324122922Sandre KASSERT(inc != NULL, ("tcp_hc_insert with NULL in_conninfo pointer")); 325122922Sandre 326122922Sandre /* 327122922Sandre * Hash the foreign ip address 328122922Sandre */ 329122922Sandre if (inc->inc_isipv6) 330122922Sandre hash = HOSTCACHE_HASH6(&inc->inc6_faddr); 331122922Sandre else 332122922Sandre hash = HOSTCACHE_HASH(&inc->inc_faddr); 333122922Sandre 334122922Sandre hc_head = &tcp_hostcache.hashbase[hash]; 335122922Sandre 336122922Sandre /* 337122922Sandre * aquire lock for this bucket row 338122922Sandre * we release the lock if we don't find an entry, 339122922Sandre * otherwise the caller has to unlock after he is done 340122922Sandre */ 341122922Sandre THC_LOCK(&hc_head->hch_mtx); 342122922Sandre 343122922Sandre /* 344122922Sandre * If the bucket limit is reached reuse the least used element 345122922Sandre */ 346122922Sandre if (hc_head->hch_length >= tcp_hostcache.bucket_limit || 347122922Sandre tcp_hostcache.cache_count >= tcp_hostcache.cache_limit) { 348122922Sandre hc_entry = TAILQ_LAST(&hc_head->hch_bucket, hc_qhead); 349122922Sandre /* 350122922Sandre * At first we were dropping the last element, just to 351122922Sandre * reaquire it in the next two lines again which ain't 352122922Sandre * very efficient. Instead just reuse the least used element. 353123028Sandre * Maybe we drop something that is still "in-use" but we can 354122922Sandre * be "lossy". 355122922Sandre */ 356122922Sandre TAILQ_REMOVE(&hc_head->hch_bucket, hc_entry, rmx_q); 357122922Sandre tcp_hostcache.hashbase[hash].hch_length--; 358122922Sandre tcp_hostcache.cache_count--; 359123028Sandre tcpstat.tcps_hc_bucketoverflow++; 360123028Sandre#if 0 361123028Sandre uma_zfree(tcp_hostcache.zone, hc_entry); 362122922Sandre#endif 363122922Sandre } else { 364122922Sandre /* 365122922Sandre * Allocate a new entry, or balk if not possible 366122922Sandre */ 367122922Sandre hc_entry = uma_zalloc(tcp_hostcache.zone, M_NOWAIT); 368122922Sandre if (hc_entry == NULL) { 369122922Sandre THC_UNLOCK(&hc_head->hch_mtx); 370122922Sandre return NULL; 371122922Sandre } 372122922Sandre } 373122922Sandre 374122922Sandre /* 375122922Sandre * Initialize basic information of hostcache entry 376122922Sandre */ 377122922Sandre bzero(hc_entry, sizeof(*hc_entry)); 378122922Sandre if (inc->inc_isipv6) 379123113Sandre bcopy(&inc->inc6_faddr, &hc_entry->ip6, sizeof(hc_entry->ip6)); 380122922Sandre else 381122922Sandre hc_entry->ip4 = inc->inc_faddr; 382122922Sandre hc_entry->rmx_head = hc_head; 383122922Sandre hc_entry->rmx_expire = tcp_hostcache.expire; 384122922Sandre 385122922Sandre /* 386122922Sandre * Put it upfront 387122922Sandre */ 388122922Sandre TAILQ_INSERT_HEAD(&hc_head->hch_bucket, hc_entry, rmx_q); 389122922Sandre tcp_hostcache.hashbase[hash].hch_length++; 390122922Sandre tcp_hostcache.cache_count++; 391122922Sandre tcpstat.tcps_hc_added++; 392122922Sandre 393122922Sandre return hc_entry; 394122922Sandre} 395122922Sandre 396122922Sandre/* 397122922Sandre * External function: lookup an entry in the hostcache and fill out the 398122922Sandre * supplied tcp metrics structure. Fills in null when no entry was found 399122922Sandre * or a value is not set. 400122922Sandre */ 401122922Sandrevoid 402122922Sandretcp_hc_get(struct in_conninfo *inc, struct hc_metrics_lite *hc_metrics_lite) 403122922Sandre{ 404122922Sandre struct hc_metrics *hc_entry; 405122922Sandre 406122922Sandre /* 407122922Sandre * Find the right bucket 408122922Sandre */ 409122922Sandre hc_entry = tcp_hc_lookup(inc); 410122922Sandre 411122922Sandre /* 412122922Sandre * If we don't have an existing object 413122922Sandre */ 414122922Sandre if (hc_entry == NULL) { 415122922Sandre bzero(hc_metrics_lite, sizeof(*hc_metrics_lite)); 416122922Sandre return; 417122922Sandre } 418122922Sandre hc_entry->rmx_hits++; 419122922Sandre hc_entry->rmx_expire = tcp_hostcache.expire; /* start over again */ 420122922Sandre 421122922Sandre hc_metrics_lite->rmx_mtu = hc_entry->rmx_mtu; 422122922Sandre hc_metrics_lite->rmx_ssthresh = hc_entry->rmx_ssthresh; 423122922Sandre hc_metrics_lite->rmx_rtt = hc_entry->rmx_rtt; 424122922Sandre hc_metrics_lite->rmx_rttvar = hc_entry->rmx_rttvar; 425122922Sandre hc_metrics_lite->rmx_bandwidth = hc_entry->rmx_bandwidth; 426122922Sandre hc_metrics_lite->rmx_cwnd = hc_entry->rmx_cwnd; 427122922Sandre hc_metrics_lite->rmx_sendpipe = hc_entry->rmx_sendpipe; 428122922Sandre hc_metrics_lite->rmx_recvpipe = hc_entry->rmx_recvpipe; 429122922Sandre 430122922Sandre /* 431122922Sandre * unlock bucket row 432122922Sandre */ 433122922Sandre THC_UNLOCK(&hc_entry->rmx_head->hch_mtx); 434122922Sandre} 435122922Sandre 436122922Sandre/* 437122922Sandre * External function: lookup an entry in the hostcache and return the 438138409Srwatson * discovered path mtu. Returns null if no entry is found or value is not 439138409Srwatson * set. 440122922Sandre */ 441122922Sandreu_long 442122922Sandretcp_hc_getmtu(struct in_conninfo *inc) 443122922Sandre{ 444122922Sandre struct hc_metrics *hc_entry; 445122922Sandre u_long mtu; 446122922Sandre 447122922Sandre hc_entry = tcp_hc_lookup(inc); 448122922Sandre if (hc_entry == NULL) { 449122922Sandre return 0; 450122922Sandre } 451122922Sandre hc_entry->rmx_hits++; 452122922Sandre hc_entry->rmx_expire = tcp_hostcache.expire; /* start over again */ 453122922Sandre 454122922Sandre mtu = hc_entry->rmx_mtu; 455122922Sandre THC_UNLOCK(&hc_entry->rmx_head->hch_mtx); 456122922Sandre return mtu; 457122922Sandre} 458122922Sandre 459122922Sandre/* 460122922Sandre * External function: update the mtu value of an entry in the hostcache. 461122922Sandre * Creates a new entry if none was found. 462122922Sandre */ 463122922Sandrevoid 464122922Sandretcp_hc_updatemtu(struct in_conninfo *inc, u_long mtu) 465122922Sandre{ 466122922Sandre struct hc_metrics *hc_entry; 467122922Sandre 468122922Sandre /* 469122922Sandre * Find the right bucket 470122922Sandre */ 471122922Sandre hc_entry = tcp_hc_lookup(inc); 472122922Sandre 473122922Sandre /* 474122922Sandre * If we don't have an existing object try to insert a new one 475122922Sandre */ 476122922Sandre if (hc_entry == NULL) { 477122922Sandre hc_entry = tcp_hc_insert(inc); 478122922Sandre if (hc_entry == NULL) 479122922Sandre return; 480122922Sandre } 481122922Sandre hc_entry->rmx_updates++; 482122922Sandre hc_entry->rmx_expire = tcp_hostcache.expire; /* start over again */ 483122922Sandre 484122922Sandre hc_entry->rmx_mtu = mtu; 485122922Sandre 486122922Sandre /* 487122922Sandre * put it upfront so we find it faster next time 488122922Sandre */ 489122922Sandre TAILQ_REMOVE(&hc_entry->rmx_head->hch_bucket, hc_entry, rmx_q); 490122922Sandre TAILQ_INSERT_HEAD(&hc_entry->rmx_head->hch_bucket, hc_entry, rmx_q); 491122922Sandre 492122922Sandre /* 493122922Sandre * unlock bucket row 494122922Sandre */ 495122922Sandre THC_UNLOCK(&hc_entry->rmx_head->hch_mtx); 496122922Sandre} 497122922Sandre 498122922Sandre/* 499122922Sandre * External function: update the tcp metrics of an entry in the hostcache. 500122922Sandre * Creates a new entry if none was found. 501122922Sandre */ 502122922Sandrevoid 503122922Sandretcp_hc_update(struct in_conninfo *inc, struct hc_metrics_lite *hcml) 504122922Sandre{ 505122922Sandre struct hc_metrics *hc_entry; 506122922Sandre 507122922Sandre hc_entry = tcp_hc_lookup(inc); 508122922Sandre if (hc_entry == NULL) { 509122922Sandre hc_entry = tcp_hc_insert(inc); 510122922Sandre if (hc_entry == NULL) 511122922Sandre return; 512122922Sandre } 513122922Sandre hc_entry->rmx_updates++; 514122922Sandre hc_entry->rmx_expire = tcp_hostcache.expire; /* start over again */ 515122922Sandre 516122922Sandre if (hcml->rmx_rtt != 0) { 517122922Sandre if (hc_entry->rmx_rtt == 0) 518122922Sandre hc_entry->rmx_rtt = hcml->rmx_rtt; 519122922Sandre else 520122922Sandre hc_entry->rmx_rtt = 521122922Sandre (hc_entry->rmx_rtt + hcml->rmx_rtt) / 2; 522122922Sandre tcpstat.tcps_cachedrtt++; 523122922Sandre } 524122922Sandre if (hcml->rmx_rttvar != 0) { 525122922Sandre if (hc_entry->rmx_rttvar == 0) 526133874Srwatson hc_entry->rmx_rttvar = hcml->rmx_rttvar; 527122922Sandre else 528122922Sandre hc_entry->rmx_rttvar = 529122922Sandre (hc_entry->rmx_rttvar + hcml->rmx_rttvar) / 2; 530122922Sandre tcpstat.tcps_cachedrttvar++; 531122922Sandre } 532122922Sandre if (hcml->rmx_ssthresh != 0) { 533122922Sandre if (hc_entry->rmx_ssthresh == 0) 534122922Sandre hc_entry->rmx_ssthresh = hcml->rmx_ssthresh; 535122922Sandre else 536122922Sandre hc_entry->rmx_ssthresh = 537122922Sandre (hc_entry->rmx_ssthresh + hcml->rmx_ssthresh) / 2; 538122922Sandre tcpstat.tcps_cachedssthresh++; 539122922Sandre } 540122922Sandre if (hcml->rmx_bandwidth != 0) { 541122922Sandre if (hc_entry->rmx_bandwidth == 0) 542122922Sandre hc_entry->rmx_bandwidth = hcml->rmx_bandwidth; 543122922Sandre else 544122922Sandre hc_entry->rmx_bandwidth = 545122922Sandre (hc_entry->rmx_bandwidth + hcml->rmx_bandwidth) / 2; 546122922Sandre /* tcpstat.tcps_cachedbandwidth++; */ 547122922Sandre } 548122922Sandre if (hcml->rmx_cwnd != 0) { 549122922Sandre if (hc_entry->rmx_cwnd == 0) 550122922Sandre hc_entry->rmx_cwnd = hcml->rmx_cwnd; 551122922Sandre else 552122922Sandre hc_entry->rmx_cwnd = 553122922Sandre (hc_entry->rmx_cwnd + hcml->rmx_cwnd) / 2; 554122922Sandre /* tcpstat.tcps_cachedcwnd++; */ 555122922Sandre } 556122922Sandre if (hcml->rmx_sendpipe != 0) { 557122922Sandre if (hc_entry->rmx_sendpipe == 0) 558122922Sandre hc_entry->rmx_sendpipe = hcml->rmx_sendpipe; 559122922Sandre else 560122922Sandre hc_entry->rmx_sendpipe = 561122922Sandre (hc_entry->rmx_sendpipe + hcml->rmx_sendpipe) /2; 562133874Srwatson /* tcpstat.tcps_cachedsendpipe++; */ 563133874Srwatson } 564122922Sandre if (hcml->rmx_recvpipe != 0) { 565122922Sandre if (hc_entry->rmx_recvpipe == 0) 566122922Sandre hc_entry->rmx_recvpipe = hcml->rmx_recvpipe; 567122922Sandre else 568122922Sandre hc_entry->rmx_recvpipe = 569122922Sandre (hc_entry->rmx_recvpipe + hcml->rmx_recvpipe) /2; 570122922Sandre /* tcpstat.tcps_cachedrecvpipe++; */ 571122922Sandre } 572122922Sandre 573122922Sandre TAILQ_REMOVE(&hc_entry->rmx_head->hch_bucket, hc_entry, rmx_q); 574122922Sandre TAILQ_INSERT_HEAD(&hc_entry->rmx_head->hch_bucket, hc_entry, rmx_q); 575122922Sandre THC_UNLOCK(&hc_entry->rmx_head->hch_mtx); 576122922Sandre} 577122922Sandre 578122922Sandre/* 579122922Sandre * Sysctl function: prints the list and values of all hostcache entries in 580122922Sandre * unsorted order. 581122922Sandre */ 582122922Sandrestatic int 583122922Sandresysctl_tcp_hc_list(SYSCTL_HANDLER_ARGS) 584122922Sandre{ 585122922Sandre int bufsize; 586122922Sandre int linesize = 128; 587122922Sandre char *p, *buf; 588122922Sandre int len, i, error; 589122922Sandre struct hc_metrics *hc_entry; 590122922Sandre 591122922Sandre bufsize = linesize * (tcp_hostcache.cache_count + 1); 592122922Sandre 593122922Sandre p = buf = (char *)malloc(bufsize, M_TEMP, M_WAITOK|M_ZERO); 594122922Sandre 595122922Sandre len = snprintf(p, linesize, 596122922Sandre "\nIP address MTU SSTRESH RTT RTTVAR BANDWIDTH " 597122922Sandre " CWND SENDPIPE RECVPIPE HITS UPD EXP\n"); 598122922Sandre p += len; 599122922Sandre 600122922Sandre#define msec(u) (((u) + 500) / 1000) 601122922Sandre for (i = 0; i < tcp_hostcache.hashsize; i++) { 602122922Sandre THC_LOCK(&tcp_hostcache.hashbase[i].hch_mtx); 603122922Sandre TAILQ_FOREACH(hc_entry, &tcp_hostcache.hashbase[i].hch_bucket, 604122922Sandre rmx_q) { 605122922Sandre len = snprintf(p, linesize, 606122922Sandre "%-15s %5lu %8lu %6lums %6lums %9lu %8lu %8lu %8lu " 607122922Sandre "%4lu %4lu %4i\n", 608122922Sandre hc_entry->ip4.s_addr ? inet_ntoa(hc_entry->ip4) : 609122922Sandre#ifdef INET6 610122922Sandre ip6_sprintf(&hc_entry->ip6), 611122922Sandre#else 612122922Sandre "IPv6?", 613122922Sandre#endif 614122922Sandre hc_entry->rmx_mtu, 615122922Sandre hc_entry->rmx_ssthresh, 616122922Sandre msec(hc_entry->rmx_rtt * 617122922Sandre (RTM_RTTUNIT / (hz * TCP_RTT_SCALE))), 618122922Sandre msec(hc_entry->rmx_rttvar * 619122922Sandre (RTM_RTTUNIT / (hz * TCP_RTT_SCALE))), 620133477Sandre hc_entry->rmx_bandwidth * 8, 621122922Sandre hc_entry->rmx_cwnd, 622122922Sandre hc_entry->rmx_sendpipe, 623122922Sandre hc_entry->rmx_recvpipe, 624122922Sandre hc_entry->rmx_hits, 625122922Sandre hc_entry->rmx_updates, 626122922Sandre hc_entry->rmx_expire); 627122922Sandre p += len; 628122922Sandre } 629122922Sandre THC_UNLOCK(&tcp_hostcache.hashbase[i].hch_mtx); 630122922Sandre } 631122922Sandre#undef msec 632122922Sandre error = SYSCTL_OUT(req, buf, p - buf); 633122922Sandre free(buf, M_TEMP); 634122922Sandre return(error); 635122922Sandre} 636122922Sandre 637122922Sandre/* 638122922Sandre * Expire and purge (old|all) entries in the tcp_hostcache. Runs periodically 639122922Sandre * from the callout. 640122922Sandre */ 641122922Sandrestatic void 642122922Sandretcp_hc_purge(void *arg) 643122922Sandre{ 644128574Sandre struct hc_metrics *hc_entry, *hc_next; 645122922Sandre int all = (intptr_t)arg; 646122922Sandre int i; 647122922Sandre 648122922Sandre if (tcp_hostcache.purgeall) { 649122922Sandre all = 1; 650122922Sandre tcp_hostcache.purgeall = 0; 651122922Sandre } 652122922Sandre 653122922Sandre for (i = 0; i < tcp_hostcache.hashsize; i++) { 654122922Sandre THC_LOCK(&tcp_hostcache.hashbase[i].hch_mtx); 655128574Sandre TAILQ_FOREACH_SAFE(hc_entry, &tcp_hostcache.hashbase[i].hch_bucket, 656128574Sandre rmx_q, hc_next) { 657122922Sandre if (all || hc_entry->rmx_expire <= 0) { 658122922Sandre TAILQ_REMOVE(&tcp_hostcache.hashbase[i].hch_bucket, 659122922Sandre hc_entry, rmx_q); 660122922Sandre uma_zfree(tcp_hostcache.zone, hc_entry); 661122922Sandre tcp_hostcache.hashbase[i].hch_length--; 662122922Sandre tcp_hostcache.cache_count--; 663122922Sandre } else 664122922Sandre hc_entry->rmx_expire -= TCP_HOSTCACHE_PRUNE; 665122922Sandre } 666122922Sandre THC_UNLOCK(&tcp_hostcache.hashbase[i].hch_mtx); 667122922Sandre } 668122922Sandre callout_reset(&tcp_hc_callout, TCP_HOSTCACHE_PRUNE * hz, tcp_hc_purge, 0); 669122922Sandre} 670