1 /* 2 * Copyright (c) 2017 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Matthew Dillon <dillon@backplane.com> 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in 15 * the documentation and/or other materials provided with the 16 * distribution. 17 * 3. Neither the name of The DragonFly Project nor the names of its 18 * contributors may be used to endorse or promote products derived 19 * from this software without specific, prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 #ifndef _SYS_INDEFINITE2_H_ 35 #define _SYS_INDEFINITE2_H_ 36 37 /* 38 * Indefinite info collection and handling code for contention loops 39 */ 40 #ifndef _SYS_INDEFINITE_H_ 41 #include <sys/indefinite.h> 42 #endif 43 #ifndef _SYS_GLOBALDATA_H_ 44 #include <sys/globaldata.h> 45 #endif 46 #ifdef _KERNEL_VIRTUAL 47 #include <pthread.h> 48 #endif 49 50 /* 51 * Initialize the indefinite state (only if the TSC is supported) 52 */ 53 static __inline void 54 indefinite_init(indefinite_info_t *info, const char *ident, char now, char type) 55 { 56 info->ident = ident; 57 info->secs = 0; 58 info->count = 0; 59 info->reported = now; 60 61 if (tsc_frequency) { 62 info->type = type; 63 /* info->base = rdtsc(); (see indefinite_check()) */ 64 } else { 65 info->type = 0; 66 info->base = 0; 67 } 68 if (now && info->ident) { 69 mycpu->gd_cnt.v_lock_name[0] = info->type; 70 strncpy(mycpu->gd_cnt.v_lock_name + 1, info->ident, 71 sizeof(mycpu->gd_cnt.v_lock_name) - 2); 72 } 73 } 74 75 /* 76 * Update the state during any loop, record collision time in microseconds. 77 */ 78 static __inline int 79 indefinite_check(indefinite_info_t *info) 80 { 81 tsc_uclock_t delta; 82 const char *str; 83 84 #ifdef _KERNEL_VIRTUAL 85 pthread_yield(); 86 #else 87 cpu_pause(); 88 #endif 89 if (info->type == 0) 90 return FALSE; 91 if (info->count == INDEF_INFO_START) { /* start recording time */ 92 info->base = rdtsc(); 93 if (info->reported == 0 && info->ident) { 94 mycpu->gd_cnt.v_lock_name[0] = info->type; 95 strncpy(mycpu->gd_cnt.v_lock_name + 1, info->ident, 96 sizeof(mycpu->gd_cnt.v_lock_name) - 2); 97 info->reported = 1; 98 } 99 } 100 if ((++info->count & 127) != 127) 101 return FALSE; 102 info->count = 128; 103 delta = rdtsc() - info->base; 104 105 #if defined(INVARIANTS) 106 if (lock_test_mode > 0) { 107 --lock_test_mode; 108 print_backtrace(8); 109 } 110 #endif 111 112 /* 113 * Ignore minor one-second interval error accumulation in 114 * favor of ensuring that info->base is fully synchronized. 115 */ 116 if (delta >= tsc_frequency) { 117 info->secs += delta / tsc_frequency; 118 info->base += delta; 119 mycpu->gd_cnt.v_lock_colls += delta / tsc_frequency * 1000000U; 120 121 switch(info->type) { 122 case 's': 123 str = "spin_lock_sh"; 124 break; 125 case 'S': 126 str = "spin_lock_ex"; 127 break; 128 case 'm': 129 str = "mutex_sh"; 130 break; 131 case 'M': 132 str = "mutex_ex"; 133 break; 134 case 'l': 135 str = "lock_sh"; 136 break; 137 case 'L': 138 str = "lock_ex"; 139 break; 140 case 't': 141 str = "token"; 142 break; 143 default: 144 str = "lock(?)"; 145 break; 146 } 147 kprintf("%s: %s, indefinite wait (%d secs)!\n", 148 str, info->ident, info->secs); 149 if (panicstr) 150 return TRUE; 151 #if defined(INVARIANTS) 152 if (lock_test_mode) { 153 print_backtrace(-1); 154 return TRUE; 155 } 156 #endif 157 #if defined(INVARIANTS) 158 if (info->secs == 11 && 159 (info->type == 's' || info->type == 'S')) { 160 print_backtrace(-1); 161 } 162 #endif 163 if (info->secs == 60 && 164 (info->type == 's' || info->type == 'S')) { 165 panic("%s: %s, indefinite wait!", str, info->ident); 166 } 167 168 } 169 return FALSE; 170 } 171 172 /* 173 * Finalize the state, record collision time in microseconds if 174 * we got past the initial load. 175 */ 176 static __inline void 177 indefinite_done(indefinite_info_t *info) 178 { 179 tsc_uclock_t delta; 180 globaldata_t gd; 181 182 if (info->type && info->count > INDEF_INFO_START) { 183 gd = mycpu; 184 delta = rdtsc() - info->base; 185 delta = delta * 1000000U / tsc_frequency; 186 gd->gd_cnt.v_lock_colls += delta; 187 } 188 info->type = 0; 189 } 190 191 #endif 192