mcount.S (2633B)
1/* SPDX-License-Identifier: GPL-2.0 */ 2/* 3 * Copyright (C) 2000 Anton Blanchard (anton@linuxcare.com) 4 * 5 * This file implements mcount(), which is used to collect profiling data. 6 * This can also be tweaked for kernel stack overflow detection. 7 */ 8 9#include <linux/linkage.h> 10#include <asm/export.h> 11 12/* 13 * This is the main variant and is called by C code. GCC's -pg option 14 * automatically instruments every C function with a call to this. 15 */ 16 17 .text 18 .align 32 19 .globl _mcount 20 .type _mcount,#function 21 EXPORT_SYMBOL(_mcount) 22 .globl mcount 23 .type mcount,#function 24_mcount: 25mcount: 26#ifdef CONFIG_FUNCTION_TRACER 27#ifdef CONFIG_DYNAMIC_FTRACE 28 /* Do nothing, the retl/nop below is all we need. */ 29#else 30 sethi %hi(ftrace_trace_function), %g1 31 sethi %hi(ftrace_stub), %g2 32 ldx [%g1 + %lo(ftrace_trace_function)], %g1 33 or %g2, %lo(ftrace_stub), %g2 34 cmp %g1, %g2 35 be,pn %icc, 1f 36 mov %i7, %g3 37 save %sp, -176, %sp 38 mov %g3, %o1 39 jmpl %g1, %o7 40 mov %i7, %o0 41 ret 42 restore 43 /* not reached */ 441: 45#ifdef CONFIG_FUNCTION_GRAPH_TRACER 46 sethi %hi(ftrace_graph_return), %g1 47 ldx [%g1 + %lo(ftrace_graph_return)], %g3 48 cmp %g2, %g3 49 bne,pn %xcc, 5f 50 sethi %hi(ftrace_graph_entry_stub), %g2 51 sethi %hi(ftrace_graph_entry), %g1 52 or %g2, %lo(ftrace_graph_entry_stub), %g2 53 ldx [%g1 + %lo(ftrace_graph_entry)], %g1 54 cmp %g1, %g2 55 be,pt %xcc, 2f 56 nop 575: mov %i7, %g2 58 mov %fp, %g3 59 save %sp, -176, %sp 60 mov %g2, %l0 61 ba,pt %xcc, ftrace_graph_caller 62 mov %g3, %l1 63#endif 642: 65#endif 66#endif 67 retl 68 nop 69 .size _mcount,.-_mcount 70 .size mcount,.-mcount 71 72#ifdef CONFIG_FUNCTION_TRACER 73 .globl ftrace_stub 74 .type ftrace_stub,#function 75ftrace_stub: 76 retl 77 nop 78 .size ftrace_stub,.-ftrace_stub 79#ifdef CONFIG_DYNAMIC_FTRACE 80 .globl ftrace_caller 81 .type ftrace_caller,#function 82ftrace_caller: 83 mov %i7, %g2 84 mov %fp, %g3 85 save %sp, -176, %sp 86 mov %g2, %o1 87 mov %g2, %l0 88 mov %g3, %l1 89 .globl ftrace_call 90ftrace_call: 91 call ftrace_stub 92 mov %i7, %o0 93#ifdef CONFIG_FUNCTION_GRAPH_TRACER 94 .globl ftrace_graph_call 95ftrace_graph_call: 96 call ftrace_stub 97 nop 98#endif 99 ret 100 restore 101#ifdef CONFIG_FUNCTION_GRAPH_TRACER 102 .size ftrace_graph_call,.-ftrace_graph_call 103#endif 104 .size ftrace_call,.-ftrace_call 105 .size ftrace_caller,.-ftrace_caller 106#endif 107#endif 108 109#ifdef CONFIG_FUNCTION_GRAPH_TRACER 110ENTRY(ftrace_graph_caller) 111 mov %l0, %o0 112 mov %i7, %o1 113 call prepare_ftrace_return 114 mov %l1, %o2 115 ret 116 restore %o0, -8, %i7 117END(ftrace_graph_caller) 118 119ENTRY(return_to_handler) 120 save %sp, -176, %sp 121 call ftrace_return_to_handler 122 mov %fp, %o0 123 jmpl %o0 + 8, %g0 124 restore 125END(return_to_handler) 126#endif