tcp_hostcache.c revision 170434
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 170434 2007-06-08 13:35:51Z yar $ 30122922Sandre */ 31122922Sandre 32122922Sandre/* 33170030Srwatson * The tcp_hostcache moves the tcp-specific cached metrics from the routing 34170030Srwatson * table to a dedicated structure indexed by the remote IP address. It keeps 35170030Srwatson * information on the measured TCP parameters of past TCP sessions to allow 36170030Srwatson * better initial start values to be used with later connections to/from the 37170030Srwatson * same source. Depending on the network parameters (delay, bandwidth, max 38170030Srwatson * MTU, congestion window) between local and remote sites, this can lead to 39170030Srwatson * significant speed-ups for new TCP connections after the first one. 40122922Sandre * 41170030Srwatson * Due to the tcp_hostcache, all TCP-specific metrics information in the 42170030Srwatson * routing table has been removed. The inpcb no longer keeps a pointer to 43170030Srwatson * the routing entry, and protocol-initiated route cloning has been removed 44170030Srwatson * as well. With these changes, the routing table has gone back to being 45170030Srwatson * more lightwight and only carries information related to packet forwarding. 46122922Sandre * 47170030Srwatson * tcp_hostcache is designed for multiple concurrent access in SMP 48170030Srwatson * environments and high contention. All bucket rows have their own lock and 49170030Srwatson * thus multiple lookups and modifies can be done at the same time as long as 50170030Srwatson * they are in different bucket rows. If a request for insertion of a new 51170030Srwatson * record can't be satisfied, it simply returns an empty structure. Nobody 52170030Srwatson * and nothing outside of tcp_hostcache.c will ever point directly to any 53170030Srwatson * entry in the tcp_hostcache. All communication is done in an 54170030Srwatson * object-oriented way and only functions of tcp_hostcache will manipulate 55170030Srwatson * hostcache entries. Otherwise, we are unable to achieve good behaviour in 56170030Srwatson * concurrent access situations. Since tcp_hostcache is only caching 57170030Srwatson * information, there are no fatal consequences if we either can't satisfy 58170030Srwatson * any particular request or have to drop/overwrite an existing entry because 59170030Srwatson * of bucket limit memory constrains. 60122922Sandre */ 61122922Sandre 62122922Sandre/* 63122922Sandre * Many thanks to jlemon for basic structure of tcp_syncache which is being 64122922Sandre * followed here. 65122922Sandre */ 66122922Sandre 67122922Sandre#include "opt_inet6.h" 68122922Sandre 69122922Sandre#include <sys/param.h> 70122922Sandre#include <sys/systm.h> 71122922Sandre#include <sys/kernel.h> 72122922Sandre#include <sys/lock.h> 73122922Sandre#include <sys/mutex.h> 74122922Sandre#include <sys/malloc.h> 75122922Sandre#include <sys/socket.h> 76122922Sandre#include <sys/socketvar.h> 77122922Sandre#include <sys/sysctl.h> 78122922Sandre 79122922Sandre#include <net/if.h> 80122922Sandre 81122922Sandre#include <netinet/in.h> 82122922Sandre#include <netinet/in_systm.h> 83122922Sandre#include <netinet/ip.h> 84122922Sandre#include <netinet/in_var.h> 85122922Sandre#include <netinet/in_pcb.h> 86122922Sandre#include <netinet/ip_var.h> 87122922Sandre#ifdef INET6 88122922Sandre#include <netinet/ip6.h> 89122922Sandre#include <netinet6/ip6_var.h> 90122922Sandre#endif 91122922Sandre#include <netinet/tcp.h> 92122922Sandre#include <netinet/tcp_var.h> 93122922Sandre#ifdef INET6 94122922Sandre#include <netinet6/tcp6_var.h> 95122922Sandre#endif 96122922Sandre 97122922Sandre#include <vm/uma.h> 98122922Sandre 99122922Sandre 100122922SandreTAILQ_HEAD(hc_qhead, hc_metrics); 101122922Sandre 102122922Sandrestruct hc_head { 103122922Sandre struct hc_qhead hch_bucket; 104122922Sandre u_int hch_length; 105122922Sandre struct mtx hch_mtx; 106122922Sandre}; 107122922Sandre 108122922Sandrestruct hc_metrics { 109122922Sandre /* housekeeping */ 110122922Sandre TAILQ_ENTRY(hc_metrics) rmx_q; 111122922Sandre struct hc_head *rmx_head; /* head of bucket tail queue */ 112122922Sandre struct in_addr ip4; /* IP address */ 113122922Sandre struct in6_addr ip6; /* IP6 address */ 114170030Srwatson /* endpoint specific values for TCP */ 115122922Sandre u_long rmx_mtu; /* MTU for this path */ 116122922Sandre u_long rmx_ssthresh; /* outbound gateway buffer limit */ 117122922Sandre u_long rmx_rtt; /* estimated round trip time */ 118122922Sandre u_long rmx_rttvar; /* estimated rtt variance */ 119122922Sandre u_long rmx_bandwidth; /* estimated bandwidth */ 120122922Sandre u_long rmx_cwnd; /* congestion window */ 121122922Sandre u_long rmx_sendpipe; /* outbound delay-bandwidth product */ 122122922Sandre u_long rmx_recvpipe; /* inbound delay-bandwidth product */ 123170030Srwatson /* TCP hostcache internal data */ 124122922Sandre int rmx_expire; /* lifetime for object */ 125122922Sandre u_long rmx_hits; /* number of hits */ 126122922Sandre u_long rmx_updates; /* number of updates */ 127122922Sandre}; 128122922Sandre 129122922Sandre/* Arbitrary values */ 130122922Sandre#define TCP_HOSTCACHE_HASHSIZE 512 131122922Sandre#define TCP_HOSTCACHE_BUCKETLIMIT 30 132122922Sandre#define TCP_HOSTCACHE_EXPIRE 60*60 /* one hour */ 133122922Sandre#define TCP_HOSTCACHE_PRUNE 5*60 /* every 5 minutes */ 134122922Sandre 135122922Sandrestruct tcp_hostcache { 136122922Sandre struct hc_head *hashbase; 137122922Sandre uma_zone_t zone; 138122922Sandre u_int hashsize; 139122922Sandre u_int hashmask; 140122922Sandre u_int bucket_limit; 141122922Sandre u_int cache_count; 142122922Sandre u_int cache_limit; 143122922Sandre int expire; 144170434Syar int prune; 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, 159167784Sandre &tcp_hostcache.cache_limit, 0, "Overall entry limit for hostcache"); 160122922Sandre 161122922SandreSYSCTL_INT(_net_inet_tcp_hostcache, OID_AUTO, hashsize, CTLFLAG_RDTUN, 162167784Sandre &tcp_hostcache.hashsize, 0, "Size of TCP hostcache hashtable"); 163122922Sandre 164122922SandreSYSCTL_INT(_net_inet_tcp_hostcache, OID_AUTO, bucketlimit, CTLFLAG_RDTUN, 165167784Sandre &tcp_hostcache.bucket_limit, 0, "Per-bucket hash limit for hostcache"); 166122922Sandre 167122922SandreSYSCTL_INT(_net_inet_tcp_hostcache, OID_AUTO, count, CTLFLAG_RD, 168167784Sandre &tcp_hostcache.cache_count, 0, "Current number of entries in hostcache"); 169122922Sandre 170122922SandreSYSCTL_INT(_net_inet_tcp_hostcache, OID_AUTO, expire, CTLFLAG_RW, 171167784Sandre &tcp_hostcache.expire, 0, "Expire time of TCP hostcache entries"); 172122922Sandre 173170434SyarSYSCTL_INT(_net_inet_tcp_hostcache, OID_AUTO, prune, CTLFLAG_RW, 174170434Syar &tcp_hostcache.prune, 0, "Time between purge runs"); 175170434Syar 176122922SandreSYSCTL_INT(_net_inet_tcp_hostcache, OID_AUTO, purge, CTLFLAG_RW, 177167784Sandre &tcp_hostcache.purgeall, 0, "Expire all entires on next purge run"); 178122922Sandre 179122922SandreSYSCTL_PROC(_net_inet_tcp_hostcache, OID_AUTO, list, 180167784Sandre CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_SKIP, 0, 0, 181167784Sandre sysctl_tcp_hc_list, "A", "List of all hostcache entries"); 182122922Sandre 183122922Sandre 184122922Sandrestatic MALLOC_DEFINE(M_HOSTCACHE, "hostcache", "TCP hostcache"); 185122922Sandre 186122922Sandre#define HOSTCACHE_HASH(ip) \ 187133874Srwatson (((ip)->s_addr ^ ((ip)->s_addr >> 7) ^ ((ip)->s_addr >> 17)) & \ 188122922Sandre tcp_hostcache.hashmask) 189122922Sandre 190122922Sandre/* XXX: What is the recommended hash to get good entropy for IPv6 addresses? */ 191133874Srwatson#define HOSTCACHE_HASH6(ip6) \ 192122922Sandre (((ip6)->s6_addr32[0] ^ \ 193122922Sandre (ip6)->s6_addr32[1] ^ \ 194122922Sandre (ip6)->s6_addr32[2] ^ \ 195122922Sandre (ip6)->s6_addr32[3]) & \ 196122922Sandre tcp_hostcache.hashmask) 197122922Sandre 198122922Sandre#define THC_LOCK(lp) mtx_lock(lp) 199122922Sandre#define THC_UNLOCK(lp) mtx_unlock(lp) 200122922Sandre 201122922Sandrevoid 202122922Sandretcp_hc_init(void) 203122922Sandre{ 204122922Sandre int i; 205122922Sandre 206122922Sandre /* 207170030Srwatson * Initialize hostcache structures. 208122922Sandre */ 209122922Sandre tcp_hostcache.cache_count = 0; 210122922Sandre tcp_hostcache.hashsize = TCP_HOSTCACHE_HASHSIZE; 211122922Sandre tcp_hostcache.bucket_limit = TCP_HOSTCACHE_BUCKETLIMIT; 212122922Sandre tcp_hostcache.cache_limit = 213122922Sandre tcp_hostcache.hashsize * tcp_hostcache.bucket_limit; 214122922Sandre tcp_hostcache.expire = TCP_HOSTCACHE_EXPIRE; 215170434Syar tcp_hostcache.prune = TCP_HOSTCACHE_PRUNE; 216122922Sandre 217133874Srwatson TUNABLE_INT_FETCH("net.inet.tcp.hostcache.hashsize", 218122922Sandre &tcp_hostcache.hashsize); 219133874Srwatson TUNABLE_INT_FETCH("net.inet.tcp.hostcache.cachelimit", 220122922Sandre &tcp_hostcache.cache_limit); 221133874Srwatson TUNABLE_INT_FETCH("net.inet.tcp.hostcache.bucketlimit", 222122922Sandre &tcp_hostcache.bucket_limit); 223122922Sandre if (!powerof2(tcp_hostcache.hashsize)) { 224133874Srwatson printf("WARNING: hostcache hash size is not a power of 2.\n"); 225122922Sandre tcp_hostcache.hashsize = 512; /* safe default */ 226133874Srwatson } 227122922Sandre tcp_hostcache.hashmask = tcp_hostcache.hashsize - 1; 228122922Sandre 229122922Sandre /* 230170030Srwatson * Allocate the hash table. 231122922Sandre */ 232122922Sandre tcp_hostcache.hashbase = (struct hc_head *) 233122922Sandre malloc(tcp_hostcache.hashsize * sizeof(struct hc_head), 234122922Sandre M_HOSTCACHE, M_WAITOK | M_ZERO); 235122922Sandre 236122922Sandre /* 237170030Srwatson * Initialize the hash buckets. 238122922Sandre */ 239122922Sandre for (i = 0; i < tcp_hostcache.hashsize; i++) { 240122922Sandre TAILQ_INIT(&tcp_hostcache.hashbase[i].hch_bucket); 241122922Sandre tcp_hostcache.hashbase[i].hch_length = 0; 242122922Sandre mtx_init(&tcp_hostcache.hashbase[i].hch_mtx, "tcp_hc_entry", 243122922Sandre NULL, MTX_DEF); 244122922Sandre } 245122922Sandre 246122922Sandre /* 247122922Sandre * Allocate the hostcache entries. 248122922Sandre */ 249122922Sandre tcp_hostcache.zone = uma_zcreate("hostcache", sizeof(struct hc_metrics), 250133509Sandre NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 251122922Sandre uma_zone_set_max(tcp_hostcache.zone, tcp_hostcache.cache_limit); 252122922Sandre 253122922Sandre /* 254122922Sandre * Set up periodic cache cleanup. 255122922Sandre */ 256122922Sandre callout_init(&tcp_hc_callout, CALLOUT_MPSAFE); 257170434Syar callout_reset(&tcp_hc_callout, tcp_hostcache.prune * hz, tcp_hc_purge, 0); 258122922Sandre} 259122922Sandre 260122922Sandre/* 261170030Srwatson * Internal function: look up an entry in the hostcache or return NULL. 262122922Sandre * 263122922Sandre * If an entry has been returned, the caller becomes responsible for 264122922Sandre * unlocking the bucket row after he is done reading/modifying the entry. 265122922Sandre */ 266122922Sandrestatic struct hc_metrics * 267122922Sandretcp_hc_lookup(struct in_conninfo *inc) 268122922Sandre{ 269122922Sandre int hash; 270122922Sandre struct hc_head *hc_head; 271122922Sandre struct hc_metrics *hc_entry; 272122922Sandre 273122922Sandre KASSERT(inc != NULL, ("tcp_hc_lookup with NULL in_conninfo pointer")); 274122922Sandre 275122922Sandre /* 276122922Sandre * Hash the foreign ip address. 277122922Sandre */ 278122922Sandre if (inc->inc_isipv6) 279122922Sandre hash = HOSTCACHE_HASH6(&inc->inc6_faddr); 280122922Sandre else 281122922Sandre hash = HOSTCACHE_HASH(&inc->inc_faddr); 282122922Sandre 283122922Sandre hc_head = &tcp_hostcache.hashbase[hash]; 284122922Sandre 285122922Sandre /* 286170030Srwatson * Acquire lock for this bucket row; we release the lock if we don't 287170030Srwatson * find an entry, otherwise the caller has to unlock after he is 288170030Srwatson * done. 289122922Sandre */ 290122922Sandre THC_LOCK(&hc_head->hch_mtx); 291122922Sandre 292122922Sandre /* 293170030Srwatson * Iterate through entries in bucket row looking for a match. 294122922Sandre */ 295122922Sandre TAILQ_FOREACH(hc_entry, &hc_head->hch_bucket, rmx_q) { 296122922Sandre if (inc->inc_isipv6) { 297122922Sandre if (memcmp(&inc->inc6_faddr, &hc_entry->ip6, 298122922Sandre sizeof(inc->inc6_faddr)) == 0) 299122922Sandre return hc_entry; 300122922Sandre } else { 301122922Sandre if (memcmp(&inc->inc_faddr, &hc_entry->ip4, 302122922Sandre sizeof(inc->inc_faddr)) == 0) 303122922Sandre return hc_entry; 304122922Sandre } 305122922Sandre } 306122922Sandre 307122922Sandre /* 308170030Srwatson * We were unsuccessful and didn't find anything. 309122922Sandre */ 310122922Sandre THC_UNLOCK(&hc_head->hch_mtx); 311122922Sandre return NULL; 312122922Sandre} 313122922Sandre 314122922Sandre/* 315170030Srwatson * Internal function: insert an entry into the hostcache or return NULL if 316170030Srwatson * unable to allocate a new one. 317133874Srwatson * 318122922Sandre * If an entry has been returned, the caller becomes responsible for 319122922Sandre * unlocking the bucket row after he is done reading/modifying the entry. 320122922Sandre */ 321122922Sandrestatic struct hc_metrics * 322122922Sandretcp_hc_insert(struct in_conninfo *inc) 323122922Sandre{ 324122922Sandre int hash; 325122922Sandre struct hc_head *hc_head; 326122922Sandre struct hc_metrics *hc_entry; 327122922Sandre 328122922Sandre KASSERT(inc != NULL, ("tcp_hc_insert with NULL in_conninfo pointer")); 329122922Sandre 330122922Sandre /* 331170030Srwatson * Hash the foreign ip address. 332122922Sandre */ 333122922Sandre if (inc->inc_isipv6) 334122922Sandre hash = HOSTCACHE_HASH6(&inc->inc6_faddr); 335122922Sandre else 336122922Sandre hash = HOSTCACHE_HASH(&inc->inc_faddr); 337122922Sandre 338122922Sandre hc_head = &tcp_hostcache.hashbase[hash]; 339122922Sandre 340122922Sandre /* 341170030Srwatson * Acquire lock for this bucket row; we release the lock if we don't 342170030Srwatson * find an entry, otherwise the caller has to unlock after he is 343170030Srwatson * done. 344122922Sandre */ 345122922Sandre THC_LOCK(&hc_head->hch_mtx); 346122922Sandre 347122922Sandre /* 348170030Srwatson * If the bucket limit is reached, reuse the least-used element. 349122922Sandre */ 350122922Sandre if (hc_head->hch_length >= tcp_hostcache.bucket_limit || 351122922Sandre tcp_hostcache.cache_count >= tcp_hostcache.cache_limit) { 352122922Sandre hc_entry = TAILQ_LAST(&hc_head->hch_bucket, hc_qhead); 353122922Sandre /* 354122922Sandre * At first we were dropping the last element, just to 355170030Srwatson * reacquire it in the next two lines again, which isn't very 356170030Srwatson * efficient. Instead just reuse the least used element. 357170030Srwatson * We may drop something that is still "in-use" but we can be 358170030Srwatson * "lossy". 359170405Sandre * Just give up if this bucket row is empty and we don't have 360170405Sandre * anything to replace. 361122922Sandre */ 362170405Sandre if (hc_entry == NULL) { 363170405Sandre THC_UNLOCK(&hc_head->hch_mtx); 364170405Sandre return NULL; 365170405Sandre } 366122922Sandre TAILQ_REMOVE(&hc_head->hch_bucket, hc_entry, rmx_q); 367122922Sandre tcp_hostcache.hashbase[hash].hch_length--; 368122922Sandre tcp_hostcache.cache_count--; 369123028Sandre tcpstat.tcps_hc_bucketoverflow++; 370123028Sandre#if 0 371123028Sandre uma_zfree(tcp_hostcache.zone, hc_entry); 372122922Sandre#endif 373122922Sandre } else { 374122922Sandre /* 375170030Srwatson * Allocate a new entry, or balk if not possible. 376122922Sandre */ 377122922Sandre hc_entry = uma_zalloc(tcp_hostcache.zone, M_NOWAIT); 378122922Sandre if (hc_entry == NULL) { 379122922Sandre THC_UNLOCK(&hc_head->hch_mtx); 380122922Sandre return NULL; 381122922Sandre } 382122922Sandre } 383122922Sandre 384122922Sandre /* 385170030Srwatson * Initialize basic information of hostcache entry. 386122922Sandre */ 387122922Sandre bzero(hc_entry, sizeof(*hc_entry)); 388122922Sandre if (inc->inc_isipv6) 389123113Sandre bcopy(&inc->inc6_faddr, &hc_entry->ip6, sizeof(hc_entry->ip6)); 390122922Sandre else 391122922Sandre hc_entry->ip4 = inc->inc_faddr; 392122922Sandre hc_entry->rmx_head = hc_head; 393122922Sandre hc_entry->rmx_expire = tcp_hostcache.expire; 394122922Sandre 395122922Sandre /* 396170030Srwatson * Put it upfront. 397122922Sandre */ 398122922Sandre TAILQ_INSERT_HEAD(&hc_head->hch_bucket, hc_entry, rmx_q); 399122922Sandre tcp_hostcache.hashbase[hash].hch_length++; 400122922Sandre tcp_hostcache.cache_count++; 401122922Sandre tcpstat.tcps_hc_added++; 402122922Sandre 403122922Sandre return hc_entry; 404122922Sandre} 405122922Sandre 406122922Sandre/* 407170030Srwatson * External function: look up an entry in the hostcache and fill out the 408170030Srwatson * supplied TCP metrics structure. Fills in NULL when no entry was found or 409170030Srwatson * a value is not set. 410122922Sandre */ 411122922Sandrevoid 412122922Sandretcp_hc_get(struct in_conninfo *inc, struct hc_metrics_lite *hc_metrics_lite) 413122922Sandre{ 414122922Sandre struct hc_metrics *hc_entry; 415122922Sandre 416122922Sandre /* 417170030Srwatson * Find the right bucket. 418122922Sandre */ 419122922Sandre hc_entry = tcp_hc_lookup(inc); 420122922Sandre 421122922Sandre /* 422170030Srwatson * If we don't have an existing object. 423122922Sandre */ 424122922Sandre if (hc_entry == NULL) { 425122922Sandre bzero(hc_metrics_lite, sizeof(*hc_metrics_lite)); 426122922Sandre return; 427122922Sandre } 428122922Sandre hc_entry->rmx_hits++; 429122922Sandre hc_entry->rmx_expire = tcp_hostcache.expire; /* start over again */ 430122922Sandre 431122922Sandre hc_metrics_lite->rmx_mtu = hc_entry->rmx_mtu; 432122922Sandre hc_metrics_lite->rmx_ssthresh = hc_entry->rmx_ssthresh; 433122922Sandre hc_metrics_lite->rmx_rtt = hc_entry->rmx_rtt; 434122922Sandre hc_metrics_lite->rmx_rttvar = hc_entry->rmx_rttvar; 435122922Sandre hc_metrics_lite->rmx_bandwidth = hc_entry->rmx_bandwidth; 436122922Sandre hc_metrics_lite->rmx_cwnd = hc_entry->rmx_cwnd; 437122922Sandre hc_metrics_lite->rmx_sendpipe = hc_entry->rmx_sendpipe; 438122922Sandre hc_metrics_lite->rmx_recvpipe = hc_entry->rmx_recvpipe; 439122922Sandre 440122922Sandre /* 441170030Srwatson * Unlock bucket row. 442122922Sandre */ 443122922Sandre THC_UNLOCK(&hc_entry->rmx_head->hch_mtx); 444122922Sandre} 445122922Sandre 446122922Sandre/* 447170030Srwatson * External function: look up an entry in the hostcache and return the 448170030Srwatson * discovered path MTU. Returns NULL if no entry is found or value is not 449138409Srwatson * set. 450122922Sandre */ 451122922Sandreu_long 452122922Sandretcp_hc_getmtu(struct in_conninfo *inc) 453122922Sandre{ 454122922Sandre struct hc_metrics *hc_entry; 455122922Sandre u_long mtu; 456122922Sandre 457122922Sandre hc_entry = tcp_hc_lookup(inc); 458122922Sandre if (hc_entry == NULL) { 459122922Sandre return 0; 460122922Sandre } 461122922Sandre hc_entry->rmx_hits++; 462122922Sandre hc_entry->rmx_expire = tcp_hostcache.expire; /* start over again */ 463122922Sandre 464122922Sandre mtu = hc_entry->rmx_mtu; 465122922Sandre THC_UNLOCK(&hc_entry->rmx_head->hch_mtx); 466122922Sandre return mtu; 467122922Sandre} 468122922Sandre 469122922Sandre/* 470170030Srwatson * External function: update the MTU value of an entry in the hostcache. 471122922Sandre * Creates a new entry if none was found. 472122922Sandre */ 473122922Sandrevoid 474122922Sandretcp_hc_updatemtu(struct in_conninfo *inc, u_long mtu) 475122922Sandre{ 476122922Sandre struct hc_metrics *hc_entry; 477122922Sandre 478122922Sandre /* 479170030Srwatson * Find the right bucket. 480122922Sandre */ 481122922Sandre hc_entry = tcp_hc_lookup(inc); 482122922Sandre 483122922Sandre /* 484170030Srwatson * If we don't have an existing object, try to insert a new one. 485122922Sandre */ 486122922Sandre if (hc_entry == NULL) { 487122922Sandre hc_entry = tcp_hc_insert(inc); 488122922Sandre if (hc_entry == NULL) 489122922Sandre return; 490122922Sandre } 491122922Sandre hc_entry->rmx_updates++; 492122922Sandre hc_entry->rmx_expire = tcp_hostcache.expire; /* start over again */ 493122922Sandre 494122922Sandre hc_entry->rmx_mtu = mtu; 495122922Sandre 496122922Sandre /* 497170030Srwatson * Put it upfront so we find it faster next time. 498122922Sandre */ 499122922Sandre TAILQ_REMOVE(&hc_entry->rmx_head->hch_bucket, hc_entry, rmx_q); 500122922Sandre TAILQ_INSERT_HEAD(&hc_entry->rmx_head->hch_bucket, hc_entry, rmx_q); 501122922Sandre 502122922Sandre /* 503170030Srwatson * Unlock bucket row. 504122922Sandre */ 505122922Sandre THC_UNLOCK(&hc_entry->rmx_head->hch_mtx); 506122922Sandre} 507122922Sandre 508122922Sandre/* 509170030Srwatson * External function: update the TCP metrics of an entry in the hostcache. 510122922Sandre * Creates a new entry if none was found. 511122922Sandre */ 512122922Sandrevoid 513122922Sandretcp_hc_update(struct in_conninfo *inc, struct hc_metrics_lite *hcml) 514122922Sandre{ 515122922Sandre struct hc_metrics *hc_entry; 516122922Sandre 517122922Sandre hc_entry = tcp_hc_lookup(inc); 518122922Sandre if (hc_entry == NULL) { 519122922Sandre hc_entry = tcp_hc_insert(inc); 520122922Sandre if (hc_entry == NULL) 521122922Sandre return; 522122922Sandre } 523122922Sandre hc_entry->rmx_updates++; 524122922Sandre hc_entry->rmx_expire = tcp_hostcache.expire; /* start over again */ 525122922Sandre 526122922Sandre if (hcml->rmx_rtt != 0) { 527122922Sandre if (hc_entry->rmx_rtt == 0) 528122922Sandre hc_entry->rmx_rtt = hcml->rmx_rtt; 529122922Sandre else 530122922Sandre hc_entry->rmx_rtt = 531122922Sandre (hc_entry->rmx_rtt + hcml->rmx_rtt) / 2; 532122922Sandre tcpstat.tcps_cachedrtt++; 533122922Sandre } 534122922Sandre if (hcml->rmx_rttvar != 0) { 535122922Sandre if (hc_entry->rmx_rttvar == 0) 536133874Srwatson hc_entry->rmx_rttvar = hcml->rmx_rttvar; 537122922Sandre else 538122922Sandre hc_entry->rmx_rttvar = 539122922Sandre (hc_entry->rmx_rttvar + hcml->rmx_rttvar) / 2; 540122922Sandre tcpstat.tcps_cachedrttvar++; 541122922Sandre } 542122922Sandre if (hcml->rmx_ssthresh != 0) { 543122922Sandre if (hc_entry->rmx_ssthresh == 0) 544122922Sandre hc_entry->rmx_ssthresh = hcml->rmx_ssthresh; 545122922Sandre else 546122922Sandre hc_entry->rmx_ssthresh = 547122922Sandre (hc_entry->rmx_ssthresh + hcml->rmx_ssthresh) / 2; 548122922Sandre tcpstat.tcps_cachedssthresh++; 549122922Sandre } 550122922Sandre if (hcml->rmx_bandwidth != 0) { 551122922Sandre if (hc_entry->rmx_bandwidth == 0) 552122922Sandre hc_entry->rmx_bandwidth = hcml->rmx_bandwidth; 553122922Sandre else 554122922Sandre hc_entry->rmx_bandwidth = 555122922Sandre (hc_entry->rmx_bandwidth + hcml->rmx_bandwidth) / 2; 556122922Sandre /* tcpstat.tcps_cachedbandwidth++; */ 557122922Sandre } 558122922Sandre if (hcml->rmx_cwnd != 0) { 559122922Sandre if (hc_entry->rmx_cwnd == 0) 560122922Sandre hc_entry->rmx_cwnd = hcml->rmx_cwnd; 561122922Sandre else 562122922Sandre hc_entry->rmx_cwnd = 563122922Sandre (hc_entry->rmx_cwnd + hcml->rmx_cwnd) / 2; 564122922Sandre /* tcpstat.tcps_cachedcwnd++; */ 565122922Sandre } 566122922Sandre if (hcml->rmx_sendpipe != 0) { 567122922Sandre if (hc_entry->rmx_sendpipe == 0) 568122922Sandre hc_entry->rmx_sendpipe = hcml->rmx_sendpipe; 569122922Sandre else 570122922Sandre hc_entry->rmx_sendpipe = 571122922Sandre (hc_entry->rmx_sendpipe + hcml->rmx_sendpipe) /2; 572133874Srwatson /* tcpstat.tcps_cachedsendpipe++; */ 573133874Srwatson } 574122922Sandre if (hcml->rmx_recvpipe != 0) { 575122922Sandre if (hc_entry->rmx_recvpipe == 0) 576122922Sandre hc_entry->rmx_recvpipe = hcml->rmx_recvpipe; 577122922Sandre else 578122922Sandre hc_entry->rmx_recvpipe = 579122922Sandre (hc_entry->rmx_recvpipe + hcml->rmx_recvpipe) /2; 580122922Sandre /* tcpstat.tcps_cachedrecvpipe++; */ 581122922Sandre } 582122922Sandre 583122922Sandre TAILQ_REMOVE(&hc_entry->rmx_head->hch_bucket, hc_entry, rmx_q); 584122922Sandre TAILQ_INSERT_HEAD(&hc_entry->rmx_head->hch_bucket, hc_entry, rmx_q); 585122922Sandre THC_UNLOCK(&hc_entry->rmx_head->hch_mtx); 586122922Sandre} 587122922Sandre 588122922Sandre/* 589122922Sandre * Sysctl function: prints the list and values of all hostcache entries in 590122922Sandre * unsorted order. 591122922Sandre */ 592122922Sandrestatic int 593122922Sandresysctl_tcp_hc_list(SYSCTL_HANDLER_ARGS) 594122922Sandre{ 595122922Sandre int bufsize; 596122922Sandre int linesize = 128; 597122922Sandre char *p, *buf; 598122922Sandre int len, i, error; 599122922Sandre struct hc_metrics *hc_entry; 600165118Sbz#ifdef INET6 601165118Sbz char ip6buf[INET6_ADDRSTRLEN]; 602165118Sbz#endif 603122922Sandre 604122922Sandre bufsize = linesize * (tcp_hostcache.cache_count + 1); 605122922Sandre 606122922Sandre p = buf = (char *)malloc(bufsize, M_TEMP, M_WAITOK|M_ZERO); 607122922Sandre 608122922Sandre len = snprintf(p, linesize, 609122922Sandre "\nIP address MTU SSTRESH RTT RTTVAR BANDWIDTH " 610122922Sandre " CWND SENDPIPE RECVPIPE HITS UPD EXP\n"); 611122922Sandre p += len; 612122922Sandre 613122922Sandre#define msec(u) (((u) + 500) / 1000) 614122922Sandre for (i = 0; i < tcp_hostcache.hashsize; i++) { 615122922Sandre THC_LOCK(&tcp_hostcache.hashbase[i].hch_mtx); 616122922Sandre TAILQ_FOREACH(hc_entry, &tcp_hostcache.hashbase[i].hch_bucket, 617122922Sandre rmx_q) { 618122922Sandre len = snprintf(p, linesize, 619122922Sandre "%-15s %5lu %8lu %6lums %6lums %9lu %8lu %8lu %8lu " 620122922Sandre "%4lu %4lu %4i\n", 621122922Sandre hc_entry->ip4.s_addr ? inet_ntoa(hc_entry->ip4) : 622122922Sandre#ifdef INET6 623165118Sbz ip6_sprintf(ip6buf, &hc_entry->ip6), 624122922Sandre#else 625122922Sandre "IPv6?", 626122922Sandre#endif 627122922Sandre hc_entry->rmx_mtu, 628122922Sandre hc_entry->rmx_ssthresh, 629122922Sandre msec(hc_entry->rmx_rtt * 630122922Sandre (RTM_RTTUNIT / (hz * TCP_RTT_SCALE))), 631122922Sandre msec(hc_entry->rmx_rttvar * 632122922Sandre (RTM_RTTUNIT / (hz * TCP_RTT_SCALE))), 633133477Sandre hc_entry->rmx_bandwidth * 8, 634122922Sandre hc_entry->rmx_cwnd, 635122922Sandre hc_entry->rmx_sendpipe, 636122922Sandre hc_entry->rmx_recvpipe, 637122922Sandre hc_entry->rmx_hits, 638122922Sandre hc_entry->rmx_updates, 639122922Sandre hc_entry->rmx_expire); 640122922Sandre p += len; 641122922Sandre } 642122922Sandre THC_UNLOCK(&tcp_hostcache.hashbase[i].hch_mtx); 643122922Sandre } 644122922Sandre#undef msec 645122922Sandre error = SYSCTL_OUT(req, buf, p - buf); 646122922Sandre free(buf, M_TEMP); 647122922Sandre return(error); 648122922Sandre} 649122922Sandre 650122922Sandre/* 651170030Srwatson * Expire and purge (old|all) entries in the tcp_hostcache. Runs 652170030Srwatson * periodically from the callout. 653122922Sandre */ 654122922Sandrestatic void 655122922Sandretcp_hc_purge(void *arg) 656122922Sandre{ 657128574Sandre struct hc_metrics *hc_entry, *hc_next; 658122922Sandre int all = (intptr_t)arg; 659122922Sandre int i; 660122922Sandre 661122922Sandre if (tcp_hostcache.purgeall) { 662122922Sandre all = 1; 663122922Sandre tcp_hostcache.purgeall = 0; 664122922Sandre } 665122922Sandre 666122922Sandre for (i = 0; i < tcp_hostcache.hashsize; i++) { 667122922Sandre THC_LOCK(&tcp_hostcache.hashbase[i].hch_mtx); 668128574Sandre TAILQ_FOREACH_SAFE(hc_entry, &tcp_hostcache.hashbase[i].hch_bucket, 669128574Sandre rmx_q, hc_next) { 670122922Sandre if (all || hc_entry->rmx_expire <= 0) { 671122922Sandre TAILQ_REMOVE(&tcp_hostcache.hashbase[i].hch_bucket, 672122922Sandre hc_entry, rmx_q); 673122922Sandre uma_zfree(tcp_hostcache.zone, hc_entry); 674122922Sandre tcp_hostcache.hashbase[i].hch_length--; 675122922Sandre tcp_hostcache.cache_count--; 676122922Sandre } else 677170434Syar hc_entry->rmx_expire -= tcp_hostcache.prune; 678122922Sandre } 679122922Sandre THC_UNLOCK(&tcp_hostcache.hashbase[i].hch_mtx); 680122922Sandre } 681170434Syar callout_reset(&tcp_hc_callout, tcp_hostcache.prune * hz, tcp_hc_purge, 0); 682122922Sandre} 683