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 /* 23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #pragma ident "%Z%%M% %I% %E% SMI" 28 29 #include "umem_base.h" 30 #include "vmem_base.h" 31 32 #include <signal.h> 33 34 /*ARGSUSED*/ 35 static void * 36 umem_update_thread(void *arg) 37 { 38 struct timeval now; 39 int in_update = 0; 40 41 (void) mutex_lock(&umem_update_lock); 42 43 ASSERT(umem_update_thr == thr_self()); 44 ASSERT(umem_st_update_thr == 0); 45 46 for (;;) { 47 umem_process_updates(); 48 49 if (in_update) { 50 in_update = 0; 51 /* 52 * we wait until now to set the next update time 53 * so that the updates are self-throttling 54 */ 55 (void) gettimeofday(&umem_update_next, NULL); 56 umem_update_next.tv_sec += umem_reap_interval; 57 } 58 59 switch (umem_reaping) { 60 case UMEM_REAP_DONE: 61 case UMEM_REAP_ADDING: 62 break; 63 64 case UMEM_REAP_ACTIVE: 65 umem_reap_next = gethrtime() + 66 (hrtime_t)umem_reap_interval * NANOSEC; 67 umem_reaping = UMEM_REAP_DONE; 68 break; 69 70 default: 71 ASSERT(umem_reaping == UMEM_REAP_DONE || 72 umem_reaping == UMEM_REAP_ADDING || 73 umem_reaping == UMEM_REAP_ACTIVE); 74 break; 75 } 76 77 (void) gettimeofday(&now, NULL); 78 if (now.tv_sec > umem_update_next.tv_sec || 79 (now.tv_sec == umem_update_next.tv_sec && 80 now.tv_usec >= umem_update_next.tv_usec)) { 81 /* 82 * Time to run an update 83 */ 84 (void) mutex_unlock(&umem_update_lock); 85 86 vmem_update(NULL); 87 /* 88 * umem_cache_update can use umem_add_update to 89 * request further work. The update is not complete 90 * until all such work is finished. 91 */ 92 umem_cache_applyall(umem_cache_update); 93 94 (void) mutex_lock(&umem_update_lock); 95 in_update = 1; 96 continue; /* start processing immediately */ 97 } 98 99 /* 100 * if there is no work to do, we wait until it is time for 101 * next update, or someone wakes us. 102 */ 103 if (umem_null_cache.cache_unext == &umem_null_cache) { 104 int cancel_state; 105 timespec_t abs_time; 106 abs_time.tv_sec = umem_update_next.tv_sec; 107 abs_time.tv_nsec = umem_update_next.tv_usec * 1000; 108 109 (void) pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, 110 &cancel_state); 111 (void) cond_timedwait(&umem_update_cv, 112 &umem_update_lock, &abs_time); 113 (void) pthread_setcancelstate(cancel_state, NULL); 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