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 2008 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 /* 29 * The event generator in this module is the producer half of a 30 * metering system which blocks flows using consumer routines in the 31 * flowop_library.c module. Four routines in that module can limit rates 32 * by event rate (flowoplib_eventlimit), by I/O operations rate 33 * (flowoplib_iopslimit()), by operations rate (flowoplib_opslimit), 34 * or by I/O bandwidth limit (flowoplib_bwlimit). By setting appropriate 35 * event generation rates, required calls per second, I/O ops per second, 36 * file system ops per second, or I/O bandwidth per second limits can 37 * be set. Note, the generated events are shared with all consumer 38 * flowops, of which their will be one for each process / thread 39 * instance which has a consumer flowop defined in it. 40 */ 41 42 #include <sys/time.h> 43 #include "vars.h" 44 #include "eventgen.h" 45 #include "filebench.h" 46 #include "flowop.h" 47 #include "ipc.h" 48 49 /* 50 * Prints "how to use" information for the eventgen module 51 */ 52 void 53 eventgen_usage(void) 54 { 55 (void) fprintf(stderr, "eventgen rate=<rate>\n"); 56 (void) fprintf(stderr, "\n"); 57 } 58 59 /* 60 * The producer side of the event system. 61 * Once eventgen_hz has been set by eventgen_setrate(), 62 * the routine sends eventgen_hz events per second until 63 * the program terminates. Events are posted by incrementing 64 * filebench_shm->shm_eventgen_q by the number of generated 65 * events then signalling the condition variable 66 * filebench_shm->shm_eventgen_cv to indicate to event consumers 67 * that more events are available. 68 * 69 * Eventgen_thread attempts to sleep for 10 event periods, 70 * then, once awakened, determines how many periods actually 71 * passed since sleeping, and issues a set of events equal 72 * to the number of periods that it slept, thus keeping the 73 * average rate at the requested rate. 74 */ 75 static void 76 eventgen_thread(void) 77 { 78 hrtime_t last; 79 80 last = gethrtime(); 81 82 /* CONSTCOND */ 83 while (1) { 84 struct timespec sleeptime; 85 hrtime_t delta; 86 int count; 87 88 if (filebench_shm->shm_eventgen_hz == 0) { 89 (void) sleep(1); 90 continue; 91 } 92 /* Sleep for 10xperiod */ 93 sleeptime.tv_sec = 0; 94 sleeptime.tv_nsec = FB_SEC2NSEC / 95 filebench_shm->shm_eventgen_hz; 96 97 sleeptime.tv_nsec *= 10; 98 if (sleeptime.tv_nsec < 1000UL) 99 sleeptime.tv_nsec = 1000UL; 100 101 sleeptime.tv_sec = sleeptime.tv_nsec / FB_SEC2NSEC; 102 if (sleeptime.tv_sec > 0) 103 sleeptime.tv_nsec -= (sleeptime.tv_sec * FB_SEC2NSEC); 104 105 (void) nanosleep(&sleeptime, NULL); 106 delta = gethrtime() - last; 107 last = gethrtime(); 108 count = (filebench_shm->shm_eventgen_hz * delta) / FB_SEC2NSEC; 109 110 filebench_log(LOG_DEBUG_SCRIPT, 111 "delta %llums count %d", 112 (u_longlong_t)(delta / 1000000), count); 113 114 /* Send 'count' events */ 115 (void) ipc_mutex_lock(&filebench_shm->shm_eventgen_lock); 116 /* Keep the producer with a max of 5 second depth */ 117 if (filebench_shm->shm_eventgen_q < 118 (5 * filebench_shm->shm_eventgen_hz)) 119 filebench_shm->shm_eventgen_q += count; 120 121 (void) pthread_cond_signal(&filebench_shm->shm_eventgen_cv); 122 123 (void) ipc_mutex_unlock(&filebench_shm->shm_eventgen_lock); 124 } 125 } 126 127 /* 128 * Creates a thread to run the event generator eventgen_thread 129 * routine. Shuts down filebench if the eventgen thread cannot 130 * be created. 131 */ 132 void 133 eventgen_init(void) 134 { 135 /* 136 * Linux does not like it if the first 137 * argument to pthread_create is null. It actually 138 * segv's. -neel 139 */ 140 pthread_t tid; 141 142 if (pthread_create(&tid, NULL, 143 (void *(*)(void*))eventgen_thread, 0) != 0) { 144 filebench_log(LOG_ERROR, "create timer thread failed: %s", 145 strerror(errno)); 146 filebench_shutdown(1); 147 } 148 } 149 150 /* 151 * Puts the current event rate in the integer portion of the 152 * supplied var_t. Returns a pointer to the var_t. 153 */ 154 var_t * 155 eventgen_ratevar(var_t *var) 156 { 157 VAR_SET_INT(var, filebench_shm->shm_eventgen_hz); 158 return (var); 159 } 160 161 /* 162 * Sets the event generator rate to that supplied by 163 * fbint_t rate. 164 */ 165 void 166 eventgen_setrate(fbint_t rate) 167 { 168 filebench_shm->shm_eventgen_hz = (int)rate; 169 } 170 171 /* 172 * Turns off the event generator by setting the rate to zero 173 */ 174 void 175 eventgen_reset(void) 176 { 177 filebench_shm->shm_eventgen_q = 0; 178 } 179