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/glolbaldata.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, int now, char type) 55 { 56 info->ident = ident; 57 info->secs = 0; 58 info->count = 0; 59 60 if (tsc_frequency) { 61 info->type = type; 62 /* info->base = rdtsc(); (see indefinite_check()) */ 63 } else { 64 info->type = 0; 65 info->base = 0; 66 } 67 if (now && info->ident) { 68 mycpu->gd_cnt.v_lock_name[0] = info->type; 69 strncpy(mycpu->gd_cnt.v_lock_name + 1, info->ident, 70 sizeof(mycpu->gd_cnt.v_lock_name) - 2); 71 } 72 } 73 74 /* 75 * Update the state during any loop, record collision time in microseconds. 76 */ 77 static __inline int 78 indefinite_check(indefinite_info_t *info) 79 { 80 tsc_uclock_t delta; 81 const char *str; 82 83 #ifdef _KERNEL_VIRTUAL 84 pthread_yield(); 85 #else 86 cpu_pause(); 87 #endif 88 if (info->type == 0) 89 return FALSE; 90 if (info->count == INDEF_INFO_START) /* start recording time */ 91 info->base = rdtsc(); 92 if ((++info->count & 127) != 127) 93 return FALSE; 94 info->count = 128; 95 delta = rdtsc() - info->base; 96 97 #if defined(INVARIANTS) 98 if (lock_test_mode > 0) { 99 --lock_test_mode; 100 print_backtrace(8); 101 } 102 #endif 103 104 /* 105 * Ignore minor one-second interval error accumulation in 106 * favor of ensuring that info->base is fully synchronized. 107 */ 108 if (info->secs == 0 && delta > tsc_oneus_approx && info->ident) { 109 mycpu->gd_cnt.v_lock_name[0] = info->type; 110 strncpy(mycpu->gd_cnt.v_lock_name + 1, info->ident, 111 sizeof(mycpu->gd_cnt.v_lock_name) - 2); 112 } 113 if (delta >= tsc_frequency) { 114 info->secs += delta / tsc_frequency; 115 info->base += delta; 116 mycpu->gd_cnt.v_lock_colls += delta / tsc_frequency * 1000000U; 117 118 switch(info->type) { 119 case 's': 120 str = "spin_lock_sh"; 121 break; 122 case 'S': 123 str = "spin_lock_ex"; 124 break; 125 case 'm': 126 str = "mutex_sh"; 127 break; 128 case 'M': 129 str = "mutex_ex"; 130 break; 131 case 'l': 132 str = "lock_sh"; 133 break; 134 case 'L': 135 str = "lock_ex"; 136 break; 137 case 't': 138 str = "token"; 139 break; 140 default: 141 str = "lock(?)"; 142 break; 143 } 144 kprintf("%s: %s, indefinite wait (%d secs)!\n", 145 str, info->ident, info->secs); 146 if (panicstr) 147 return TRUE; 148 #if defined(INVARIANTS) 149 if (lock_test_mode) { 150 print_backtrace(-1); 151 return TRUE; 152 } 153 #endif 154 #if defined(INVARIANTS) 155 if (info->secs == 11 && 156 (info->type == 's' || info->type == 'S')) { 157 print_backtrace(-1); 158 } 159 #endif 160 if (info->secs == 60 && 161 (info->type == 's' || info->type == 'S')) { 162 panic("%s: %s, indefinite wait!", str, info->ident); 163 } 164 165 } 166 return FALSE; 167 } 168 169 /* 170 * Finalize the state, record collision time in microseconds if 171 * we got past the initial load. 172 */ 173 static __inline void 174 indefinite_done(indefinite_info_t *info) 175 { 176 tsc_uclock_t delta; 177 178 if (info->type && info->count > INDEF_INFO_START) { 179 delta = rdtsc() - info->base; 180 delta = delta * 1000000U / tsc_frequency; 181 mycpu->gd_cnt.v_lock_colls += delta; 182 } 183 info->type = 0; 184 } 185 186 #endif 187