Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 | // SPDX-License-Identifier: GPL-2.0-only #include <linux/module.h> #include <linux/mm.h> /* for handle_mm_fault() */ #include <linux/ftrace.h> #include <linux/sched/stat.h> #ifndef CONFIG_ARM64 #include <asm/asm-offsets.h> #endif extern void my_direct_func(unsigned long ip); void my_direct_func(unsigned long ip) { trace_printk("ip %lx\n", ip); } extern void my_tramp(void *); #ifdef CONFIG_RISCV #include <asm/asm.h> asm ( " .pushsection .text, \"ax\", @progbits\n" " .type my_tramp, @function\n" " .globl my_tramp\n" " my_tramp:\n" " addi sp,sp,-3*"SZREG"\n" " "REG_S" a0,0*"SZREG"(sp)\n" " "REG_S" t0,1*"SZREG"(sp)\n" " "REG_S" ra,2*"SZREG"(sp)\n" " mv a0,t0\n" " call my_direct_func\n" " "REG_L" a0,0*"SZREG"(sp)\n" " "REG_L" t0,1*"SZREG"(sp)\n" " "REG_L" ra,2*"SZREG"(sp)\n" " addi sp,sp,3*"SZREG"\n" " jr t0\n" " .size my_tramp, .-my_tramp\n" " .popsection\n" ); #endif /* CONFIG_RISCV */ #ifdef CONFIG_X86_64 #include <asm/ibt.h> #include <asm/nospec-branch.h> asm ( " .pushsection .text, \"ax\", @progbits\n" " .type my_tramp, @function\n" " .globl my_tramp\n" " my_tramp:" ASM_ENDBR " pushq %rbp\n" " movq %rsp, %rbp\n" CALL_DEPTH_ACCOUNT " pushq %rdi\n" " movq 8(%rbp), %rdi\n" " call my_direct_func\n" " popq %rdi\n" " leave\n" ASM_RET " .size my_tramp, .-my_tramp\n" " .popsection\n" ); #endif /* CONFIG_X86_64 */ #ifdef CONFIG_S390 asm ( " .pushsection .text, \"ax\", @progbits\n" " .type my_tramp, @function\n" " .globl my_tramp\n" " my_tramp:" " lgr %r1,%r15\n" " stmg %r0,%r5,"__stringify(__SF_GPRS)"(%r15)\n" " stg %r14,"__stringify(__SF_GPRS+8*8)"(%r15)\n" " aghi %r15,"__stringify(-STACK_FRAME_OVERHEAD)"\n" " stg %r1,"__stringify(__SF_BACKCHAIN)"(%r15)\n" " lgr %r2,%r0\n" " brasl %r14,my_direct_func\n" " aghi %r15,"__stringify(STACK_FRAME_OVERHEAD)"\n" " lmg %r0,%r5,"__stringify(__SF_GPRS)"(%r15)\n" " lg %r14,"__stringify(__SF_GPRS+8*8)"(%r15)\n" " lgr %r1,%r0\n" " br %r1\n" " .size my_tramp, .-my_tramp\n" " .popsection\n" ); #endif /* CONFIG_S390 */ #ifdef CONFIG_ARM64 asm ( " .pushsection .text, \"ax\", @progbits\n" " .type my_tramp, @function\n" " .globl my_tramp\n" " my_tramp:" " hint 34\n" // bti c " sub sp, sp, #32\n" " stp x9, x30, [sp]\n" " str x0, [sp, #16]\n" " mov x0, x30\n" " bl my_direct_func\n" " ldp x30, x9, [sp]\n" " ldr x0, [sp, #16]\n" " add sp, sp, #32\n" " ret x9\n" " .size my_tramp, .-my_tramp\n" " .popsection\n" ); #endif /* CONFIG_ARM64 */ #ifdef CONFIG_LOONGARCH #include <asm/asm.h> asm ( " .pushsection .text, \"ax\", @progbits\n" " .type my_tramp, @function\n" " .globl my_tramp\n" " my_tramp:\n" " addi.d $sp, $sp, -32\n" " st.d $a0, $sp, 0\n" " st.d $t0, $sp, 8\n" " st.d $ra, $sp, 16\n" " move $a0, $t0\n" " bl my_direct_func\n" " ld.d $a0, $sp, 0\n" " ld.d $t0, $sp, 8\n" " ld.d $ra, $sp, 16\n" " addi.d $sp, $sp, 32\n" " jr $t0\n" " .size my_tramp, .-my_tramp\n" " .popsection\n" ); #endif /* CONFIG_LOONGARCH */ static struct ftrace_ops direct; static int __init ftrace_direct_multi_init(void) { ftrace_set_filter_ip(&direct, (unsigned long) wake_up_process, 0, 0); ftrace_set_filter_ip(&direct, (unsigned long) schedule, 0, 0); return register_ftrace_direct(&direct, (unsigned long) my_tramp); } static void __exit ftrace_direct_multi_exit(void) { unregister_ftrace_direct(&direct, (unsigned long) my_tramp, true); } module_init(ftrace_direct_multi_init); module_exit(ftrace_direct_multi_exit); MODULE_AUTHOR("Jiri Olsa"); MODULE_DESCRIPTION("Example use case of using register_ftrace_direct_multi()"); MODULE_LICENSE("GPL"); |