1 /* 2 * Copyright 2017 Facebook, Inc. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #pragma once 18 19 // Default constraint for the probe arguments as operands. 20 #ifndef FOLLY_SDT_ARG_CONSTRAINT 21 #if defined(__powerpc64__) || defined(__powerpc__) 22 #define FOLLY_SDT_ARG_CONSTRAINT "nZr" 23 #else 24 #define FOLLY_SDT_ARG_CONSTRAINT "nor" 25 #endif 26 #endif 27 28 // Instruction to emit for the probe. 29 #define FOLLY_SDT_NOP nop 30 31 // Note section properties. 32 #define FOLLY_SDT_NOTE_NAME "stapsdt" 33 #define FOLLY_SDT_NOTE_TYPE 3 34 35 // Size of address depending on platform. 36 #ifdef __LP64__ 37 #define FOLLY_SDT_ASM_ADDR .8byte 38 #else 39 #define FOLLY_SDT_ASM_ADDR .4byte 40 #endif 41 42 // Assembler helper Macros. 43 #define FOLLY_SDT_S(x) #x 44 #define FOLLY_SDT_ASM_1(x) FOLLY_SDT_S(x) "\n" 45 #define FOLLY_SDT_ASM_2(a, b) FOLLY_SDT_S(a) "," FOLLY_SDT_S(b) "\n" 46 #define FOLLY_SDT_ASM_3(a, b, c) FOLLY_SDT_S(a) "," FOLLY_SDT_S(b) "," \ 47 FOLLY_SDT_S(c) "\n" 48 #define FOLLY_SDT_ASM_STRING(x) FOLLY_SDT_ASM_1(.asciz FOLLY_SDT_S(x)) 49 50 // Helper to determine the size of an argument. 51 #define FOLLY_SDT_ISARRAY(x) (__builtin_classify_type(x) == 14) 52 #define FOLLY_SDT_ARGSIZE(x) (FOLLY_SDT_ISARRAY(x) ? sizeof(void*) : sizeof(x)) 53 54 // Format of each probe arguments as operand. 55 // Size of the arugment tagged with FOLLY_SDT_Sn, with "n" constraint. 56 // Value of the argument tagged with FOLLY_SDT_An, with configured constraint. 57 #define FOLLY_SDT_ARG(n, x) \ 58 [FOLLY_SDT_S##n] "n" ((size_t)FOLLY_SDT_ARGSIZE(x)), \ 59 [FOLLY_SDT_A##n] FOLLY_SDT_ARG_CONSTRAINT (x) 60 61 // Templates to append arguments as operands. 62 #define FOLLY_SDT_OPERANDS_0() [__sdt_dummy] "g" (0) 63 #define FOLLY_SDT_OPERANDS_1(_1) FOLLY_SDT_ARG(1, _1) 64 #define FOLLY_SDT_OPERANDS_2(_1, _2) \ 65 FOLLY_SDT_OPERANDS_1(_1), FOLLY_SDT_ARG(2, _2) 66 #define FOLLY_SDT_OPERANDS_3(_1, _2, _3) \ 67 FOLLY_SDT_OPERANDS_2(_1, _2), FOLLY_SDT_ARG(3, _3) 68 #define FOLLY_SDT_OPERANDS_4(_1, _2, _3, _4) \ 69 FOLLY_SDT_OPERANDS_3(_1, _2, _3), FOLLY_SDT_ARG(4, _4) 70 #define FOLLY_SDT_OPERANDS_5(_1, _2, _3, _4, _5) \ 71 FOLLY_SDT_OPERANDS_4(_1, _2, _3, _4), FOLLY_SDT_ARG(5, _5) 72 #define FOLLY_SDT_OPERANDS_6(_1, _2, _3, _4, _5, _6) \ 73 FOLLY_SDT_OPERANDS_5(_1, _2, _3, _4, _5), FOLLY_SDT_ARG(6, _6) 74 #define FOLLY_SDT_OPERANDS_7(_1, _2, _3, _4, _5, _6, _7) \ 75 FOLLY_SDT_OPERANDS_6(_1, _2, _3, _4, _5, _6), FOLLY_SDT_ARG(7, _7) 76 #define FOLLY_SDT_OPERANDS_8(_1, _2, _3, _4, _5, _6, _7, _8) \ 77 FOLLY_SDT_OPERANDS_7(_1, _2, _3, _4, _5, _6, _7), FOLLY_SDT_ARG(8, _8) 78 79 // Templates to reference the arguments from operands in note section. 80 #if defined(__powerpc64__ ) || defined(__powerpc__) 81 #define FOLLY_SDT_ARGTMPL(id) %I[id]%[id] 82 #elif defined(__i386__) 83 #define FOLLY_SDT_ARGTMPL(id) %w[id] 84 #else 85 #define FOLLY_SDT_ARGTMPL(id) %[id] 86 #endif 87 #define FOLLY_SDT_ARGFMT(no) %n[FOLLY_SDT_S##no]@FOLLY_SDT_ARGTMPL(FOLLY_SDT_A##no) 88 #define FOLLY_SDT_ARG_TEMPLATE_0 /*No arguments*/ 89 #define FOLLY_SDT_ARG_TEMPLATE_1 FOLLY_SDT_ARGFMT(1) 90 #define FOLLY_SDT_ARG_TEMPLATE_2 FOLLY_SDT_ARG_TEMPLATE_1 FOLLY_SDT_ARGFMT(2) 91 #define FOLLY_SDT_ARG_TEMPLATE_3 FOLLY_SDT_ARG_TEMPLATE_2 FOLLY_SDT_ARGFMT(3) 92 #define FOLLY_SDT_ARG_TEMPLATE_4 FOLLY_SDT_ARG_TEMPLATE_3 FOLLY_SDT_ARGFMT(4) 93 #define FOLLY_SDT_ARG_TEMPLATE_5 FOLLY_SDT_ARG_TEMPLATE_4 FOLLY_SDT_ARGFMT(5) 94 #define FOLLY_SDT_ARG_TEMPLATE_6 FOLLY_SDT_ARG_TEMPLATE_5 FOLLY_SDT_ARGFMT(6) 95 #define FOLLY_SDT_ARG_TEMPLATE_7 FOLLY_SDT_ARG_TEMPLATE_6 FOLLY_SDT_ARGFMT(7) 96 #define FOLLY_SDT_ARG_TEMPLATE_8 FOLLY_SDT_ARG_TEMPLATE_7 FOLLY_SDT_ARGFMT(8) 97 98 // Structure of note section for the probe. 99 #define FOLLY_SDT_NOTE_CONTENT(provider, name, arg_template) \ 100 FOLLY_SDT_ASM_1(990: FOLLY_SDT_NOP) \ 101 FOLLY_SDT_ASM_3( .pushsection .note.stapsdt,"","note") \ 102 FOLLY_SDT_ASM_1( .balign 4) \ 103 FOLLY_SDT_ASM_3( .4byte 992f-991f, 994f-993f, FOLLY_SDT_NOTE_TYPE) \ 104 FOLLY_SDT_ASM_1(991: .asciz FOLLY_SDT_NOTE_NAME) \ 105 FOLLY_SDT_ASM_1(992: .balign 4) \ 106 FOLLY_SDT_ASM_1(993: FOLLY_SDT_ASM_ADDR 990b) \ 107 FOLLY_SDT_ASM_1( FOLLY_SDT_ASM_ADDR 0) /*Reserved for Semaphore address*/\ 108 FOLLY_SDT_ASM_1( FOLLY_SDT_ASM_ADDR 0) /*Reserved for Semaphore name*/ \ 109 FOLLY_SDT_ASM_STRING(provider) \ 110 FOLLY_SDT_ASM_STRING(name) \ 111 FOLLY_SDT_ASM_STRING(arg_template) \ 112 FOLLY_SDT_ASM_1(994: .balign 4) \ 113 FOLLY_SDT_ASM_1( .popsection) 114 115 // Main probe Macro. 116 #define FOLLY_SDT_PROBE(provider, name, n, arglist) \ 117 __asm__ __volatile__ ( \ 118 FOLLY_SDT_NOTE_CONTENT(provider, name, FOLLY_SDT_ARG_TEMPLATE_##n) \ 119 :: FOLLY_SDT_OPERANDS_##n arglist \ 120 ) \ 121 122 // Helper Macros to handle variadic arguments. 123 #define FOLLY_SDT_NARG_(_0, _1, _2, _3, _4, _5, _6, _7, _8, N, ...) N 124 #define FOLLY_SDT_NARG(...) \ 125 FOLLY_SDT_NARG_(__VA_ARGS__, 8, 7, 6, 5, 4, 3, 2, 1, 0) 126 #define FOLLY_SDT_PROBE_N(provider, name, N, ...) \ 127 FOLLY_SDT_PROBE(provider, name, N, (__VA_ARGS__)) 128