1 /*- 2 * Copyright (c) 2012 Konstantin Belousov <kib@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD$ 27 */ 28 29 #ifndef __MACHINE_COUNTER_H__ 30 #define __MACHINE_COUNTER_H__ 31 32 #include <sys/pcpu.h> 33 #ifdef INVARIANTS 34 #include <sys/proc.h> 35 #endif 36 #include <machine/md_var.h> 37 #include <machine/specialreg.h> 38 39 #define counter_enter() do { \ 40 if ((cpu_feature & CPUID_CX8) == 0) \ 41 critical_enter(); \ 42 } while (0) 43 44 #define counter_exit() do { \ 45 if ((cpu_feature & CPUID_CX8) == 0) \ 46 critical_exit(); \ 47 } while (0) 48 49 extern struct pcpu __pcpu[MAXCPU]; 50 51 static inline void 52 counter_64_inc_8b(uint64_t *p, int64_t inc) 53 { 54 55 __asm __volatile( 56 "movl %%fs:(%%esi),%%eax\n\t" 57 "movl %%fs:4(%%esi),%%edx\n" 58 "1:\n\t" 59 "movl %%eax,%%ebx\n\t" 60 "movl %%edx,%%ecx\n\t" 61 "addl (%%edi),%%ebx\n\t" 62 "adcl 4(%%edi),%%ecx\n\t" 63 "cmpxchg8b %%fs:(%%esi)\n\t" 64 "jnz 1b" 65 : 66 : "S" ((char *)p - (char *)&__pcpu[0]), "D" (&inc) 67 : "memory", "cc", "eax", "edx", "ebx", "ecx"); 68 } 69 70 #ifdef IN_SUBR_COUNTER_C 71 static inline uint64_t 72 counter_u64_read_one_8b(uint64_t *p) 73 { 74 uint32_t res_lo, res_high; 75 76 __asm __volatile( 77 "movl %%eax,%%ebx\n\t" 78 "movl %%edx,%%ecx\n\t" 79 "cmpxchg8b (%2)" 80 : "=a" (res_lo), "=d"(res_high) 81 : "SD" (p) 82 : "cc", "ebx", "ecx"); 83 return (res_lo + ((uint64_t)res_high << 32)); 84 } 85 86 static inline uint64_t 87 counter_u64_fetch_inline(uint64_t *p) 88 { 89 uint64_t res; 90 int i; 91 92 res = 0; 93 if ((cpu_feature & CPUID_CX8) == 0) { 94 /* 95 * The machines without cmpxchg8b are not SMP. 96 * Disabling the preemption provides atomicity of the 97 * counter reading, since update is done in the 98 * critical section as well. 99 */ 100 critical_enter(); 101 for (i = 0; i < mp_ncpus; i++) { 102 res += *(uint64_t *)((char *)p + 103 sizeof(struct pcpu) * i); 104 } 105 critical_exit(); 106 } else { 107 for (i = 0; i < mp_ncpus; i++) 108 res += counter_u64_read_one_8b((uint64_t *)((char *)p + 109 sizeof(struct pcpu) * i)); 110 } 111 return (res); 112 } 113 114 static inline void 115 counter_u64_zero_one_8b(uint64_t *p) 116 { 117 118 __asm __volatile( 119 "movl (%0),%%eax\n\t" 120 "movl 4(%0),%%edx\n" 121 "xorl %%ebx,%%ebx\n\t" 122 "xorl %%ecx,%%ecx\n\t" 123 "1:\n\t" 124 "cmpxchg8b (%0)\n\t" 125 "jnz 1b" 126 : 127 : "SD" (p) 128 : "memory", "cc", "eax", "edx", "ebx", "ecx"); 129 } 130 131 static void 132 counter_u64_zero_one_cpu(void *arg) 133 { 134 uint64_t *p; 135 136 p = (uint64_t *)((char *)arg + sizeof(struct pcpu) * PCPU_GET(cpuid)); 137 counter_u64_zero_one_8b(p); 138 } 139 140 static inline void 141 counter_u64_zero_inline(counter_u64_t c) 142 { 143 int i; 144 145 if ((cpu_feature & CPUID_CX8) == 0) { 146 critical_enter(); 147 for (i = 0; i < mp_ncpus; i++) 148 *(uint64_t *)((char *)c + sizeof(struct pcpu) * i) = 0; 149 critical_exit(); 150 } else { 151 smp_rendezvous(smp_no_rendevous_barrier, 152 counter_u64_zero_one_cpu, smp_no_rendevous_barrier, c); 153 } 154 } 155 #endif 156 157 #define counter_u64_add_protected(c, inc) do { \ 158 if ((cpu_feature & CPUID_CX8) == 0) { \ 159 CRITICAL_ASSERT(curthread); \ 160 *(uint64_t *)zpcpu_get(c) += (inc); \ 161 } else \ 162 counter_64_inc_8b((c), (inc)); \ 163 } while (0) 164 165 static inline void 166 counter_u64_add(counter_u64_t c, int64_t inc) 167 { 168 169 if ((cpu_feature & CPUID_CX8) == 0) { 170 critical_enter(); 171 *(uint64_t *)zpcpu_get(c) += inc; 172 critical_exit(); 173 } else { 174 counter_64_inc_8b(c, inc); 175 } 176 } 177 178 #endif /* ! __MACHINE_COUNTER_H__ */ 179