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 47 /* 48 * Initialize the indefinite state (only if the TSC is supported) 49 */ 50 static __inline void 51 indefinite_init(indefinite_info_t *info, const char *ident, char now, char type) 52 { 53 info->ident = ident; 54 info->secs = 0; 55 info->count = 0; 56 info->reported = now; 57 58 if (tsc_frequency) { 59 info->type = type; 60 /* info->base = rdtsc(); (see indefinite_check()) */ 61 } else { 62 info->type = 0; 63 info->base = 0; 64 } 65 if (now && info->ident) { 66 mycpu->gd_cnt.v_lock_name[0] = info->type; 67 strncpy(mycpu->gd_cnt.v_lock_name + 1, info->ident, 68 sizeof(mycpu->gd_cnt.v_lock_name) - 2); 69 } 70 } 71 72 /* 73 * Update the state during any loop, record collision time in microseconds. 74 */ 75 static __inline int 76 indefinite_check(indefinite_info_t *info) 77 { 78 tsc_uclock_t delta; 79 const char *str; 80 81 #ifdef _KERNEL_VIRTUAL 82 vkernel_yield(); 83 #else 84 cpu_pause(); 85 #endif 86 if (info->type == 0) 87 return FALSE; 88 if (info->count == INDEF_INFO_START) { /* start recording time */ 89 info->base = rdtsc(); 90 if (info->reported == 0 && info->ident) { 91 mycpu->gd_cnt.v_lock_name[0] = info->type; 92 strncpy(mycpu->gd_cnt.v_lock_name + 1, info->ident, 93 sizeof(mycpu->gd_cnt.v_lock_name) - 2); 94 info->reported = 1; 95 } 96 } 97 if ((++info->count & 127) != 127) 98 return FALSE; 99 info->count = 128; 100 delta = rdtsc() - info->base; 101 102 #if defined(INVARIANTS) 103 if (lock_test_mode > 0) { 104 --lock_test_mode; 105 print_backtrace(8); 106 } 107 #endif 108 109 /* 110 * Ignore minor one-second interval error accumulation in 111 * favor of ensuring that info->base is fully synchronized. 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 globaldata_t gd; 178 179 if (info->type && info->count > INDEF_INFO_START) { 180 gd = mycpu; 181 delta = rdtsc() - info->base; 182 delta = delta * 1000000U / tsc_frequency; 183 gd->gd_cnt.v_lock_colls += delta; 184 } 185 info->type = 0; 186 } 187 188 #endif 189