tcp_hostcache.c revision 195727
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 40182411Srpaulo * routing table have 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 195727 2009-07-16 21:13:04Z rwatson $"); 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> 79181803Sbz#include <sys/vimage.h> 80122922Sandre 81122922Sandre#include <net/if.h> 82194739Sbz#include <net/route.h> 83122922Sandre 84122922Sandre#include <netinet/in.h> 85122922Sandre#include <netinet/in_systm.h> 86122922Sandre#include <netinet/ip.h> 87122922Sandre#include <netinet/in_var.h> 88122922Sandre#include <netinet/in_pcb.h> 89122922Sandre#include <netinet/ip_var.h> 90122922Sandre#ifdef INET6 91122922Sandre#include <netinet/ip6.h> 92122922Sandre#include <netinet6/ip6_var.h> 93122922Sandre#endif 94122922Sandre#include <netinet/tcp.h> 95122922Sandre#include <netinet/tcp_var.h> 96185571Sbz#include <netinet/tcp_hostcache.h> 97122922Sandre#ifdef INET6 98122922Sandre#include <netinet6/tcp6_var.h> 99122922Sandre#endif 100122922Sandre 101122922Sandre#include <vm/uma.h> 102122922Sandre 103122922Sandre/* Arbitrary values */ 104122922Sandre#define TCP_HOSTCACHE_HASHSIZE 512 105122922Sandre#define TCP_HOSTCACHE_BUCKETLIMIT 30 106122922Sandre#define TCP_HOSTCACHE_EXPIRE 60*60 /* one hour */ 107122922Sandre#define TCP_HOSTCACHE_PRUNE 5*60 /* every 5 minutes */ 108122922Sandre 109195699Srwatsonstatic VNET_DEFINE(struct tcp_hostcache, tcp_hostcache); 110195699Srwatsonstatic VNET_DEFINE(struct callout, tcp_hc_callout); 111122922Sandre 112195727Srwatson#define V_tcp_hostcache VNET(tcp_hostcache) 113195727Srwatson#define V_tcp_hc_callout VNET(tcp_hc_callout) 114195699Srwatson 115122922Sandrestatic struct hc_metrics *tcp_hc_lookup(struct in_conninfo *); 116122922Sandrestatic struct hc_metrics *tcp_hc_insert(struct in_conninfo *); 117122922Sandrestatic int sysctl_tcp_hc_list(SYSCTL_HANDLER_ARGS); 118122922Sandrestatic void tcp_hc_purge(void *); 119122922Sandre 120182633SbrooksSYSCTL_NODE(_net_inet_tcp, OID_AUTO, hostcache, CTLFLAG_RW, 0, 121182633Sbrooks "TCP Host cache"); 122122922Sandre 123195699SrwatsonSYSCTL_VNET_INT(_net_inet_tcp_hostcache, OID_AUTO, cachelimit, CTLFLAG_RDTUN, 124195699Srwatson &VNET_NAME(tcp_hostcache.cache_limit), 0, 125183550Szec "Overall entry limit for hostcache"); 126122922Sandre 127195699SrwatsonSYSCTL_VNET_INT(_net_inet_tcp_hostcache, OID_AUTO, hashsize, CTLFLAG_RDTUN, 128195699Srwatson &VNET_NAME(tcp_hostcache.hashsize), 0, 129183550Szec "Size of TCP hostcache hashtable"); 130122922Sandre 131195699SrwatsonSYSCTL_VNET_INT(_net_inet_tcp_hostcache, OID_AUTO, bucketlimit, 132195699Srwatson CTLFLAG_RDTUN, &VNET_NAME(tcp_hostcache.bucket_limit), 0, 133183550Szec "Per-bucket hash limit for hostcache"); 134122922Sandre 135195699SrwatsonSYSCTL_VNET_INT(_net_inet_tcp_hostcache, OID_AUTO, count, CTLFLAG_RD, 136195699Srwatson &VNET_NAME(tcp_hostcache.cache_count), 0, 137183550Szec "Current number of entries in hostcache"); 138122922Sandre 139195699SrwatsonSYSCTL_VNET_INT(_net_inet_tcp_hostcache, OID_AUTO, expire, CTLFLAG_RW, 140195699Srwatson &VNET_NAME(tcp_hostcache.expire), 0, 141183550Szec "Expire time of TCP hostcache entries"); 142122922Sandre 143195699SrwatsonSYSCTL_VNET_INT(_net_inet_tcp_hostcache, OID_AUTO, prune, CTLFLAG_RW, 144195699Srwatson &VNET_NAME(tcp_hostcache.prune), 0, 145195699Srwatson "Time between purge runs"); 146170434Syar 147195699SrwatsonSYSCTL_VNET_INT(_net_inet_tcp_hostcache, OID_AUTO, purge, CTLFLAG_RW, 148195699Srwatson &VNET_NAME(tcp_hostcache.purgeall), 0, 149183550Szec "Expire all entires on next purge run"); 150122922Sandre 151122922SandreSYSCTL_PROC(_net_inet_tcp_hostcache, OID_AUTO, list, 152167784Sandre CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_SKIP, 0, 0, 153167784Sandre sysctl_tcp_hc_list, "A", "List of all hostcache entries"); 154122922Sandre 155122922Sandre 156122922Sandrestatic MALLOC_DEFINE(M_HOSTCACHE, "hostcache", "TCP hostcache"); 157122922Sandre 158122922Sandre#define HOSTCACHE_HASH(ip) \ 159133874Srwatson (((ip)->s_addr ^ ((ip)->s_addr >> 7) ^ ((ip)->s_addr >> 17)) & \ 160181803Sbz V_tcp_hostcache.hashmask) 161122922Sandre 162122922Sandre/* XXX: What is the recommended hash to get good entropy for IPv6 addresses? */ 163133874Srwatson#define HOSTCACHE_HASH6(ip6) \ 164122922Sandre (((ip6)->s6_addr32[0] ^ \ 165122922Sandre (ip6)->s6_addr32[1] ^ \ 166122922Sandre (ip6)->s6_addr32[2] ^ \ 167122922Sandre (ip6)->s6_addr32[3]) & \ 168181803Sbz V_tcp_hostcache.hashmask) 169122922Sandre 170122922Sandre#define THC_LOCK(lp) mtx_lock(lp) 171122922Sandre#define THC_UNLOCK(lp) mtx_unlock(lp) 172122922Sandre 173122922Sandrevoid 174122922Sandretcp_hc_init(void) 175122922Sandre{ 176122922Sandre int i; 177122922Sandre 178122922Sandre /* 179170030Srwatson * Initialize hostcache structures. 180122922Sandre */ 181181803Sbz V_tcp_hostcache.cache_count = 0; 182181803Sbz V_tcp_hostcache.hashsize = TCP_HOSTCACHE_HASHSIZE; 183181803Sbz V_tcp_hostcache.bucket_limit = TCP_HOSTCACHE_BUCKETLIMIT; 184181803Sbz V_tcp_hostcache.cache_limit = 185181803Sbz V_tcp_hostcache.hashsize * V_tcp_hostcache.bucket_limit; 186181803Sbz V_tcp_hostcache.expire = TCP_HOSTCACHE_EXPIRE; 187181803Sbz V_tcp_hostcache.prune = TCP_HOSTCACHE_PRUNE; 188122922Sandre 189133874Srwatson TUNABLE_INT_FETCH("net.inet.tcp.hostcache.hashsize", 190181803Sbz &V_tcp_hostcache.hashsize); 191133874Srwatson TUNABLE_INT_FETCH("net.inet.tcp.hostcache.cachelimit", 192181803Sbz &V_tcp_hostcache.cache_limit); 193133874Srwatson TUNABLE_INT_FETCH("net.inet.tcp.hostcache.bucketlimit", 194181803Sbz &V_tcp_hostcache.bucket_limit); 195181803Sbz if (!powerof2(V_tcp_hostcache.hashsize)) { 196133874Srwatson printf("WARNING: hostcache hash size is not a power of 2.\n"); 197181803Sbz V_tcp_hostcache.hashsize = TCP_HOSTCACHE_HASHSIZE; /* default */ 198133874Srwatson } 199181803Sbz V_tcp_hostcache.hashmask = V_tcp_hostcache.hashsize - 1; 200122922Sandre 201122922Sandre /* 202170030Srwatson * Allocate the hash table. 203122922Sandre */ 204181803Sbz V_tcp_hostcache.hashbase = (struct hc_head *) 205181803Sbz malloc(V_tcp_hostcache.hashsize * sizeof(struct hc_head), 206122922Sandre M_HOSTCACHE, M_WAITOK | M_ZERO); 207122922Sandre 208122922Sandre /* 209170030Srwatson * Initialize the hash buckets. 210122922Sandre */ 211181803Sbz for (i = 0; i < V_tcp_hostcache.hashsize; i++) { 212181803Sbz TAILQ_INIT(&V_tcp_hostcache.hashbase[i].hch_bucket); 213181803Sbz V_tcp_hostcache.hashbase[i].hch_length = 0; 214181803Sbz mtx_init(&V_tcp_hostcache.hashbase[i].hch_mtx, "tcp_hc_entry", 215122922Sandre NULL, MTX_DEF); 216122922Sandre } 217122922Sandre 218122922Sandre /* 219122922Sandre * Allocate the hostcache entries. 220122922Sandre */ 221181887Sjulian V_tcp_hostcache.zone = 222181888Sjulian uma_zcreate("hostcache", sizeof(struct hc_metrics), 223181888Sjulian NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 224181803Sbz uma_zone_set_max(V_tcp_hostcache.zone, V_tcp_hostcache.cache_limit); 225122922Sandre 226122922Sandre /* 227122922Sandre * Set up periodic cache cleanup. 228122922Sandre */ 229181803Sbz callout_init(&V_tcp_hc_callout, CALLOUT_MPSAFE); 230181887Sjulian callout_reset(&V_tcp_hc_callout, V_tcp_hostcache.prune * hz, 231191816Szec tcp_hc_purge, curvnet); 232122922Sandre} 233122922Sandre 234193731Szec#ifdef VIMAGE 235193731Szecvoid 236193731Szectcp_hc_destroy(void) 237193731Szec{ 238193731Szec 239193731Szec /* XXX TODO walk the hashtable and free all entries */ 240193731Szec 241193731Szec callout_drain(&V_tcp_hc_callout); 242193731Szec} 243193731Szec#endif 244193731Szec 245122922Sandre/* 246170030Srwatson * Internal function: look up an entry in the hostcache or return NULL. 247122922Sandre * 248122922Sandre * If an entry has been returned, the caller becomes responsible for 249122922Sandre * unlocking the bucket row after he is done reading/modifying the entry. 250122922Sandre */ 251122922Sandrestatic struct hc_metrics * 252122922Sandretcp_hc_lookup(struct in_conninfo *inc) 253122922Sandre{ 254122922Sandre int hash; 255122922Sandre struct hc_head *hc_head; 256122922Sandre struct hc_metrics *hc_entry; 257122922Sandre 258122922Sandre KASSERT(inc != NULL, ("tcp_hc_lookup with NULL in_conninfo pointer")); 259122922Sandre 260122922Sandre /* 261122922Sandre * Hash the foreign ip address. 262122922Sandre */ 263186222Sbz if (inc->inc_flags & INC_ISIPV6) 264122922Sandre hash = HOSTCACHE_HASH6(&inc->inc6_faddr); 265122922Sandre else 266122922Sandre hash = HOSTCACHE_HASH(&inc->inc_faddr); 267122922Sandre 268181803Sbz hc_head = &V_tcp_hostcache.hashbase[hash]; 269122922Sandre 270122922Sandre /* 271170030Srwatson * Acquire lock for this bucket row; we release the lock if we don't 272170030Srwatson * find an entry, otherwise the caller has to unlock after he is 273170030Srwatson * done. 274122922Sandre */ 275122922Sandre THC_LOCK(&hc_head->hch_mtx); 276122922Sandre 277122922Sandre /* 278170030Srwatson * Iterate through entries in bucket row looking for a match. 279122922Sandre */ 280122922Sandre TAILQ_FOREACH(hc_entry, &hc_head->hch_bucket, rmx_q) { 281186222Sbz if (inc->inc_flags & INC_ISIPV6) { 282122922Sandre if (memcmp(&inc->inc6_faddr, &hc_entry->ip6, 283122922Sandre sizeof(inc->inc6_faddr)) == 0) 284122922Sandre return hc_entry; 285122922Sandre } else { 286122922Sandre if (memcmp(&inc->inc_faddr, &hc_entry->ip4, 287122922Sandre sizeof(inc->inc_faddr)) == 0) 288122922Sandre return hc_entry; 289122922Sandre } 290122922Sandre } 291122922Sandre 292122922Sandre /* 293170030Srwatson * We were unsuccessful and didn't find anything. 294122922Sandre */ 295122922Sandre THC_UNLOCK(&hc_head->hch_mtx); 296122922Sandre return NULL; 297122922Sandre} 298122922Sandre 299122922Sandre/* 300170030Srwatson * Internal function: insert an entry into the hostcache or return NULL if 301170030Srwatson * unable to allocate a new one. 302133874Srwatson * 303122922Sandre * If an entry has been returned, the caller becomes responsible for 304122922Sandre * unlocking the bucket row after he is done reading/modifying the entry. 305122922Sandre */ 306122922Sandrestatic struct hc_metrics * 307122922Sandretcp_hc_insert(struct in_conninfo *inc) 308122922Sandre{ 309122922Sandre int hash; 310122922Sandre struct hc_head *hc_head; 311122922Sandre struct hc_metrics *hc_entry; 312122922Sandre 313122922Sandre KASSERT(inc != NULL, ("tcp_hc_insert with NULL in_conninfo pointer")); 314122922Sandre 315122922Sandre /* 316170030Srwatson * Hash the foreign ip address. 317122922Sandre */ 318186222Sbz if (inc->inc_flags & INC_ISIPV6) 319122922Sandre hash = HOSTCACHE_HASH6(&inc->inc6_faddr); 320122922Sandre else 321122922Sandre hash = HOSTCACHE_HASH(&inc->inc_faddr); 322122922Sandre 323181803Sbz hc_head = &V_tcp_hostcache.hashbase[hash]; 324122922Sandre 325122922Sandre /* 326170030Srwatson * Acquire lock for this bucket row; we release the lock if we don't 327170030Srwatson * find an entry, otherwise the caller has to unlock after he is 328170030Srwatson * done. 329122922Sandre */ 330122922Sandre THC_LOCK(&hc_head->hch_mtx); 331122922Sandre 332122922Sandre /* 333170030Srwatson * If the bucket limit is reached, reuse the least-used element. 334122922Sandre */ 335181803Sbz if (hc_head->hch_length >= V_tcp_hostcache.bucket_limit || 336181803Sbz V_tcp_hostcache.cache_count >= V_tcp_hostcache.cache_limit) { 337122922Sandre hc_entry = TAILQ_LAST(&hc_head->hch_bucket, hc_qhead); 338122922Sandre /* 339122922Sandre * At first we were dropping the last element, just to 340170030Srwatson * reacquire it in the next two lines again, which isn't very 341170030Srwatson * efficient. Instead just reuse the least used element. 342170030Srwatson * We may drop something that is still "in-use" but we can be 343170030Srwatson * "lossy". 344170405Sandre * Just give up if this bucket row is empty and we don't have 345170405Sandre * anything to replace. 346122922Sandre */ 347170405Sandre if (hc_entry == NULL) { 348170405Sandre THC_UNLOCK(&hc_head->hch_mtx); 349170405Sandre return NULL; 350170405Sandre } 351122922Sandre TAILQ_REMOVE(&hc_head->hch_bucket, hc_entry, rmx_q); 352181803Sbz V_tcp_hostcache.hashbase[hash].hch_length--; 353181803Sbz V_tcp_hostcache.cache_count--; 354190948Srwatson TCPSTAT_INC(tcps_hc_bucketoverflow); 355123028Sandre#if 0 356181803Sbz uma_zfree(V_tcp_hostcache.zone, hc_entry); 357122922Sandre#endif 358122922Sandre } else { 359122922Sandre /* 360170030Srwatson * Allocate a new entry, or balk if not possible. 361122922Sandre */ 362181803Sbz hc_entry = uma_zalloc(V_tcp_hostcache.zone, M_NOWAIT); 363122922Sandre if (hc_entry == NULL) { 364122922Sandre THC_UNLOCK(&hc_head->hch_mtx); 365122922Sandre return NULL; 366122922Sandre } 367122922Sandre } 368122922Sandre 369122922Sandre /* 370170030Srwatson * Initialize basic information of hostcache entry. 371122922Sandre */ 372122922Sandre bzero(hc_entry, sizeof(*hc_entry)); 373186222Sbz if (inc->inc_flags & INC_ISIPV6) 374123113Sandre bcopy(&inc->inc6_faddr, &hc_entry->ip6, sizeof(hc_entry->ip6)); 375122922Sandre else 376122922Sandre hc_entry->ip4 = inc->inc_faddr; 377122922Sandre hc_entry->rmx_head = hc_head; 378181803Sbz hc_entry->rmx_expire = V_tcp_hostcache.expire; 379122922Sandre 380122922Sandre /* 381170030Srwatson * Put it upfront. 382122922Sandre */ 383122922Sandre TAILQ_INSERT_HEAD(&hc_head->hch_bucket, hc_entry, rmx_q); 384181803Sbz V_tcp_hostcache.hashbase[hash].hch_length++; 385181803Sbz V_tcp_hostcache.cache_count++; 386190948Srwatson TCPSTAT_INC(tcps_hc_added); 387122922Sandre 388122922Sandre return hc_entry; 389122922Sandre} 390122922Sandre 391122922Sandre/* 392170030Srwatson * External function: look up an entry in the hostcache and fill out the 393170030Srwatson * supplied TCP metrics structure. Fills in NULL when no entry was found or 394170030Srwatson * a value is not set. 395122922Sandre */ 396122922Sandrevoid 397122922Sandretcp_hc_get(struct in_conninfo *inc, struct hc_metrics_lite *hc_metrics_lite) 398122922Sandre{ 399122922Sandre struct hc_metrics *hc_entry; 400122922Sandre 401122922Sandre /* 402170030Srwatson * Find the right bucket. 403122922Sandre */ 404122922Sandre hc_entry = tcp_hc_lookup(inc); 405122922Sandre 406122922Sandre /* 407170030Srwatson * If we don't have an existing object. 408122922Sandre */ 409122922Sandre if (hc_entry == NULL) { 410122922Sandre bzero(hc_metrics_lite, sizeof(*hc_metrics_lite)); 411122922Sandre return; 412122922Sandre } 413122922Sandre hc_entry->rmx_hits++; 414181803Sbz hc_entry->rmx_expire = V_tcp_hostcache.expire; /* start over again */ 415122922Sandre 416122922Sandre hc_metrics_lite->rmx_mtu = hc_entry->rmx_mtu; 417122922Sandre hc_metrics_lite->rmx_ssthresh = hc_entry->rmx_ssthresh; 418122922Sandre hc_metrics_lite->rmx_rtt = hc_entry->rmx_rtt; 419122922Sandre hc_metrics_lite->rmx_rttvar = hc_entry->rmx_rttvar; 420122922Sandre hc_metrics_lite->rmx_bandwidth = hc_entry->rmx_bandwidth; 421122922Sandre hc_metrics_lite->rmx_cwnd = hc_entry->rmx_cwnd; 422122922Sandre hc_metrics_lite->rmx_sendpipe = hc_entry->rmx_sendpipe; 423122922Sandre hc_metrics_lite->rmx_recvpipe = hc_entry->rmx_recvpipe; 424122922Sandre 425122922Sandre /* 426170030Srwatson * Unlock bucket row. 427122922Sandre */ 428122922Sandre THC_UNLOCK(&hc_entry->rmx_head->hch_mtx); 429122922Sandre} 430122922Sandre 431122922Sandre/* 432170030Srwatson * External function: look up an entry in the hostcache and return the 433170030Srwatson * discovered path MTU. Returns NULL if no entry is found or value is not 434138409Srwatson * set. 435122922Sandre */ 436122922Sandreu_long 437122922Sandretcp_hc_getmtu(struct in_conninfo *inc) 438122922Sandre{ 439122922Sandre struct hc_metrics *hc_entry; 440122922Sandre u_long mtu; 441122922Sandre 442122922Sandre hc_entry = tcp_hc_lookup(inc); 443122922Sandre if (hc_entry == NULL) { 444122922Sandre return 0; 445122922Sandre } 446122922Sandre hc_entry->rmx_hits++; 447181803Sbz hc_entry->rmx_expire = V_tcp_hostcache.expire; /* start over again */ 448122922Sandre 449122922Sandre mtu = hc_entry->rmx_mtu; 450122922Sandre THC_UNLOCK(&hc_entry->rmx_head->hch_mtx); 451122922Sandre return mtu; 452122922Sandre} 453122922Sandre 454122922Sandre/* 455170030Srwatson * External function: update the MTU value of an entry in the hostcache. 456122922Sandre * Creates a new entry if none was found. 457122922Sandre */ 458122922Sandrevoid 459122922Sandretcp_hc_updatemtu(struct in_conninfo *inc, u_long mtu) 460122922Sandre{ 461122922Sandre struct hc_metrics *hc_entry; 462122922Sandre 463122922Sandre /* 464170030Srwatson * Find the right bucket. 465122922Sandre */ 466122922Sandre hc_entry = tcp_hc_lookup(inc); 467122922Sandre 468122922Sandre /* 469170030Srwatson * If we don't have an existing object, try to insert a new one. 470122922Sandre */ 471122922Sandre if (hc_entry == NULL) { 472122922Sandre hc_entry = tcp_hc_insert(inc); 473122922Sandre if (hc_entry == NULL) 474122922Sandre return; 475122922Sandre } 476122922Sandre hc_entry->rmx_updates++; 477181803Sbz hc_entry->rmx_expire = V_tcp_hostcache.expire; /* start over again */ 478122922Sandre 479122922Sandre hc_entry->rmx_mtu = mtu; 480122922Sandre 481122922Sandre /* 482170030Srwatson * Put it upfront so we find it faster next time. 483122922Sandre */ 484122922Sandre TAILQ_REMOVE(&hc_entry->rmx_head->hch_bucket, hc_entry, rmx_q); 485122922Sandre TAILQ_INSERT_HEAD(&hc_entry->rmx_head->hch_bucket, hc_entry, rmx_q); 486122922Sandre 487122922Sandre /* 488170030Srwatson * Unlock bucket row. 489122922Sandre */ 490122922Sandre THC_UNLOCK(&hc_entry->rmx_head->hch_mtx); 491122922Sandre} 492122922Sandre 493122922Sandre/* 494170030Srwatson * External function: update the TCP metrics of an entry in the hostcache. 495122922Sandre * Creates a new entry if none was found. 496122922Sandre */ 497122922Sandrevoid 498122922Sandretcp_hc_update(struct in_conninfo *inc, struct hc_metrics_lite *hcml) 499122922Sandre{ 500122922Sandre struct hc_metrics *hc_entry; 501122922Sandre 502122922Sandre hc_entry = tcp_hc_lookup(inc); 503122922Sandre if (hc_entry == NULL) { 504122922Sandre hc_entry = tcp_hc_insert(inc); 505122922Sandre if (hc_entry == NULL) 506122922Sandre return; 507122922Sandre } 508122922Sandre hc_entry->rmx_updates++; 509181803Sbz hc_entry->rmx_expire = V_tcp_hostcache.expire; /* start over again */ 510122922Sandre 511122922Sandre if (hcml->rmx_rtt != 0) { 512122922Sandre if (hc_entry->rmx_rtt == 0) 513122922Sandre hc_entry->rmx_rtt = hcml->rmx_rtt; 514122922Sandre else 515122922Sandre hc_entry->rmx_rtt = 516122922Sandre (hc_entry->rmx_rtt + hcml->rmx_rtt) / 2; 517190948Srwatson TCPSTAT_INC(tcps_cachedrtt); 518122922Sandre } 519122922Sandre if (hcml->rmx_rttvar != 0) { 520122922Sandre if (hc_entry->rmx_rttvar == 0) 521133874Srwatson hc_entry->rmx_rttvar = hcml->rmx_rttvar; 522122922Sandre else 523122922Sandre hc_entry->rmx_rttvar = 524122922Sandre (hc_entry->rmx_rttvar + hcml->rmx_rttvar) / 2; 525190948Srwatson TCPSTAT_INC(tcps_cachedrttvar); 526122922Sandre } 527122922Sandre if (hcml->rmx_ssthresh != 0) { 528122922Sandre if (hc_entry->rmx_ssthresh == 0) 529122922Sandre hc_entry->rmx_ssthresh = hcml->rmx_ssthresh; 530122922Sandre else 531122922Sandre hc_entry->rmx_ssthresh = 532122922Sandre (hc_entry->rmx_ssthresh + hcml->rmx_ssthresh) / 2; 533190948Srwatson TCPSTAT_INC(tcps_cachedssthresh); 534122922Sandre } 535122922Sandre if (hcml->rmx_bandwidth != 0) { 536122922Sandre if (hc_entry->rmx_bandwidth == 0) 537122922Sandre hc_entry->rmx_bandwidth = hcml->rmx_bandwidth; 538122922Sandre else 539122922Sandre hc_entry->rmx_bandwidth = 540122922Sandre (hc_entry->rmx_bandwidth + hcml->rmx_bandwidth) / 2; 541190948Srwatson /* TCPSTAT_INC(tcps_cachedbandwidth); */ 542122922Sandre } 543122922Sandre if (hcml->rmx_cwnd != 0) { 544122922Sandre if (hc_entry->rmx_cwnd == 0) 545122922Sandre hc_entry->rmx_cwnd = hcml->rmx_cwnd; 546122922Sandre else 547122922Sandre hc_entry->rmx_cwnd = 548122922Sandre (hc_entry->rmx_cwnd + hcml->rmx_cwnd) / 2; 549190948Srwatson /* TCPSTAT_INC(tcps_cachedcwnd); */ 550122922Sandre } 551122922Sandre if (hcml->rmx_sendpipe != 0) { 552122922Sandre if (hc_entry->rmx_sendpipe == 0) 553122922Sandre hc_entry->rmx_sendpipe = hcml->rmx_sendpipe; 554122922Sandre else 555122922Sandre hc_entry->rmx_sendpipe = 556122922Sandre (hc_entry->rmx_sendpipe + hcml->rmx_sendpipe) /2; 557190948Srwatson /* TCPSTAT_INC(tcps_cachedsendpipe); */ 558133874Srwatson } 559122922Sandre if (hcml->rmx_recvpipe != 0) { 560122922Sandre if (hc_entry->rmx_recvpipe == 0) 561122922Sandre hc_entry->rmx_recvpipe = hcml->rmx_recvpipe; 562122922Sandre else 563122922Sandre hc_entry->rmx_recvpipe = 564122922Sandre (hc_entry->rmx_recvpipe + hcml->rmx_recvpipe) /2; 565190948Srwatson /* TCPSTAT_INC(tcps_cachedrecvpipe); */ 566122922Sandre } 567122922Sandre 568122922Sandre TAILQ_REMOVE(&hc_entry->rmx_head->hch_bucket, hc_entry, rmx_q); 569122922Sandre TAILQ_INSERT_HEAD(&hc_entry->rmx_head->hch_bucket, hc_entry, rmx_q); 570122922Sandre THC_UNLOCK(&hc_entry->rmx_head->hch_mtx); 571122922Sandre} 572122922Sandre 573122922Sandre/* 574122922Sandre * Sysctl function: prints the list and values of all hostcache entries in 575122922Sandre * unsorted order. 576122922Sandre */ 577122922Sandrestatic int 578122922Sandresysctl_tcp_hc_list(SYSCTL_HANDLER_ARGS) 579122922Sandre{ 580122922Sandre int bufsize; 581122922Sandre int linesize = 128; 582122922Sandre char *p, *buf; 583122922Sandre int len, i, error; 584122922Sandre struct hc_metrics *hc_entry; 585165118Sbz#ifdef INET6 586165118Sbz char ip6buf[INET6_ADDRSTRLEN]; 587165118Sbz#endif 588122922Sandre 589181803Sbz bufsize = linesize * (V_tcp_hostcache.cache_count + 1); 590122922Sandre 591122922Sandre p = buf = (char *)malloc(bufsize, M_TEMP, M_WAITOK|M_ZERO); 592122922Sandre 593122922Sandre len = snprintf(p, linesize, 594122922Sandre "\nIP address MTU SSTRESH RTT RTTVAR BANDWIDTH " 595122922Sandre " CWND SENDPIPE RECVPIPE HITS UPD EXP\n"); 596122922Sandre p += len; 597122922Sandre 598122922Sandre#define msec(u) (((u) + 500) / 1000) 599181803Sbz for (i = 0; i < V_tcp_hostcache.hashsize; i++) { 600181803Sbz THC_LOCK(&V_tcp_hostcache.hashbase[i].hch_mtx); 601181803Sbz TAILQ_FOREACH(hc_entry, &V_tcp_hostcache.hashbase[i].hch_bucket, 602122922Sandre rmx_q) { 603122922Sandre len = snprintf(p, linesize, 604122922Sandre "%-15s %5lu %8lu %6lums %6lums %9lu %8lu %8lu %8lu " 605122922Sandre "%4lu %4lu %4i\n", 606122922Sandre hc_entry->ip4.s_addr ? inet_ntoa(hc_entry->ip4) : 607122922Sandre#ifdef INET6 608165118Sbz ip6_sprintf(ip6buf, &hc_entry->ip6), 609122922Sandre#else 610122922Sandre "IPv6?", 611122922Sandre#endif 612122922Sandre hc_entry->rmx_mtu, 613122922Sandre hc_entry->rmx_ssthresh, 614122922Sandre msec(hc_entry->rmx_rtt * 615122922Sandre (RTM_RTTUNIT / (hz * TCP_RTT_SCALE))), 616122922Sandre msec(hc_entry->rmx_rttvar * 617122922Sandre (RTM_RTTUNIT / (hz * TCP_RTT_SCALE))), 618133477Sandre hc_entry->rmx_bandwidth * 8, 619122922Sandre hc_entry->rmx_cwnd, 620122922Sandre hc_entry->rmx_sendpipe, 621122922Sandre hc_entry->rmx_recvpipe, 622122922Sandre hc_entry->rmx_hits, 623122922Sandre hc_entry->rmx_updates, 624122922Sandre hc_entry->rmx_expire); 625122922Sandre p += len; 626122922Sandre } 627181803Sbz THC_UNLOCK(&V_tcp_hostcache.hashbase[i].hch_mtx); 628122922Sandre } 629122922Sandre#undef msec 630122922Sandre error = SYSCTL_OUT(req, buf, p - buf); 631122922Sandre free(buf, M_TEMP); 632122922Sandre return(error); 633122922Sandre} 634122922Sandre 635122922Sandre/* 636170030Srwatson * Expire and purge (old|all) entries in the tcp_hostcache. Runs 637170030Srwatson * periodically from the callout. 638122922Sandre */ 639122922Sandrestatic void 640122922Sandretcp_hc_purge(void *arg) 641122922Sandre{ 642191816Szec CURVNET_SET((struct vnet *) arg); 643128574Sandre struct hc_metrics *hc_entry, *hc_next; 644191917Szec int all = 0; 645122922Sandre int i; 646122922Sandre 647181803Sbz if (V_tcp_hostcache.purgeall) { 648122922Sandre all = 1; 649181803Sbz V_tcp_hostcache.purgeall = 0; 650122922Sandre } 651122922Sandre 652181803Sbz for (i = 0; i < V_tcp_hostcache.hashsize; i++) { 653181803Sbz THC_LOCK(&V_tcp_hostcache.hashbase[i].hch_mtx); 654181887Sjulian TAILQ_FOREACH_SAFE(hc_entry, 655181888Sjulian &V_tcp_hostcache.hashbase[i].hch_bucket, rmx_q, hc_next) { 656122922Sandre if (all || hc_entry->rmx_expire <= 0) { 657181803Sbz TAILQ_REMOVE(&V_tcp_hostcache.hashbase[i].hch_bucket, 658122922Sandre hc_entry, rmx_q); 659181803Sbz uma_zfree(V_tcp_hostcache.zone, hc_entry); 660181803Sbz V_tcp_hostcache.hashbase[i].hch_length--; 661181803Sbz V_tcp_hostcache.cache_count--; 662122922Sandre } else 663181803Sbz hc_entry->rmx_expire -= V_tcp_hostcache.prune; 664122922Sandre } 665181803Sbz THC_UNLOCK(&V_tcp_hostcache.hashbase[i].hch_mtx); 666122922Sandre } 667181887Sjulian 668181887Sjulian callout_reset(&V_tcp_hc_callout, V_tcp_hostcache.prune * hz, 669181887Sjulian tcp_hc_purge, arg); 670191816Szec CURVNET_RESTORE(); 671122922Sandre} 672