1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #pragma ident "%Z%%M% %I% %E% SMI" 27 28 #include "umem_base.h" 29 #include "vmem_base.h" 30 31 #include <signal.h> 32 33 /* 34 * we use the _ version, since we don't want to be cancelled. 35 */ 36 extern int _cond_timedwait(cond_t *cv, mutex_t *mutex, const timespec_t *delay); 37 38 /*ARGSUSED*/ 39 static void * 40 umem_update_thread(void *arg) 41 { 42 struct timeval now; 43 int in_update = 0; 44 45 (void) mutex_lock(&umem_update_lock); 46 47 ASSERT(umem_update_thr == thr_self()); 48 ASSERT(umem_st_update_thr == 0); 49 50 for (;;) { 51 umem_process_updates(); 52 53 if (in_update) { 54 in_update = 0; 55 /* 56 * we wait until now to set the next update time 57 * so that the updates are self-throttling 58 */ 59 (void) gettimeofday(&umem_update_next, NULL); 60 umem_update_next.tv_sec += umem_reap_interval; 61 } 62 63 switch (umem_reaping) { 64 case UMEM_REAP_DONE: 65 case UMEM_REAP_ADDING: 66 break; 67 68 case UMEM_REAP_ACTIVE: 69 umem_reap_next = gethrtime() + 70 (hrtime_t)umem_reap_interval * NANOSEC; 71 umem_reaping = UMEM_REAP_DONE; 72 break; 73 74 default: 75 ASSERT(umem_reaping == UMEM_REAP_DONE || 76 umem_reaping == UMEM_REAP_ADDING || 77 umem_reaping == UMEM_REAP_ACTIVE); 78 break; 79 } 80 81 (void) gettimeofday(&now, NULL); 82 if (now.tv_sec > umem_update_next.tv_sec || 83 (now.tv_sec == umem_update_next.tv_sec && 84 now.tv_usec >= umem_update_next.tv_usec)) { 85 /* 86 * Time to run an update 87 */ 88 (void) mutex_unlock(&umem_update_lock); 89 90 vmem_update(NULL); 91 /* 92 * umem_cache_update can use umem_add_update to 93 * request further work. The update is not complete 94 * until all such work is finished. 95 */ 96 umem_cache_applyall(umem_cache_update); 97 98 (void) mutex_lock(&umem_update_lock); 99 in_update = 1; 100 continue; /* start processing immediately */ 101 } 102 103 /* 104 * if there is no work to do, we wait until it is time for 105 * next update, or someone wakes us. 106 */ 107 if (umem_null_cache.cache_unext == &umem_null_cache) { 108 timespec_t abs_time; 109 abs_time.tv_sec = umem_update_next.tv_sec; 110 abs_time.tv_nsec = umem_update_next.tv_usec * 1000; 111 112 (void) _cond_timedwait(&umem_update_cv, 113 &umem_update_lock, &abs_time); 114 } 115 } 116 /* LINTED no return statement */ 117 } 118 119 int 120 umem_create_update_thread(void) 121 { 122 sigset_t sigmask, oldmask; 123 thread_t newthread; 124 125 ASSERT(MUTEX_HELD(&umem_update_lock)); 126 ASSERT(umem_update_thr == 0); 127 128 /* 129 * The update thread handles no signals 130 */ 131 (void) sigfillset(&sigmask); 132 (void) thr_sigsetmask(SIG_BLOCK, &sigmask, &oldmask); 133 134 /* 135 * drop the umem_update_lock; we cannot hold locks acquired in 136 * pre-fork handler while calling thr_create or thr_continue(). 137 */ 138 139 (void) mutex_unlock(&umem_update_lock); 140 141 if (thr_create(NULL, NULL, umem_update_thread, NULL, 142 THR_BOUND | THR_DAEMON | THR_DETACHED | THR_SUSPENDED, 143 &newthread) == 0) { 144 (void) thr_sigsetmask(SIG_SETMASK, &oldmask, NULL); 145 146 (void) mutex_lock(&umem_update_lock); 147 /* 148 * due to the locking in umem_reap(), only one thread can 149 * ever call umem_create_update_thread() at a time. This 150 * must be the case for this code to work. 151 */ 152 153 ASSERT(umem_update_thr == 0); 154 umem_update_thr = newthread; 155 (void) mutex_unlock(&umem_update_lock); 156 (void) thr_continue(newthread); 157 (void) mutex_lock(&umem_update_lock); 158 159 return (1); 160 } else { /* thr_create failed */ 161 (void) thr_sigsetmask(SIG_SETMASK, &oldmask, NULL); 162 (void) mutex_lock(&umem_update_lock); 163 } 164 return (0); 165 } 166