diff options
Diffstat (limited to 'arch/arm64/kernel/ftrace.c')
| -rw-r--r-- | arch/arm64/kernel/ftrace.c | 87 |
1 files changed, 48 insertions, 39 deletions
diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c index 8745175f4a75..b30b955a8921 100644 --- a/arch/arm64/kernel/ftrace.c +++ b/arch/arm64/kernel/ftrace.c @@ -17,7 +17,49 @@ #include <asm/insn.h> #include <asm/patching.h> -#ifdef CONFIG_DYNAMIC_FTRACE +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_ARGS +struct fregs_offset { + const char *name; + int offset; +}; + +#define FREGS_OFFSET(n, field) \ +{ \ + .name = n, \ + .offset = offsetof(struct ftrace_regs, field), \ +} + +static const struct fregs_offset fregs_offsets[] = { + FREGS_OFFSET("x0", regs[0]), + FREGS_OFFSET("x1", regs[1]), + FREGS_OFFSET("x2", regs[2]), + FREGS_OFFSET("x3", regs[3]), + FREGS_OFFSET("x4", regs[4]), + FREGS_OFFSET("x5", regs[5]), + FREGS_OFFSET("x6", regs[6]), + FREGS_OFFSET("x7", regs[7]), + FREGS_OFFSET("x8", regs[8]), + + FREGS_OFFSET("x29", fp), + FREGS_OFFSET("x30", lr), + FREGS_OFFSET("lr", lr), + + FREGS_OFFSET("sp", sp), + FREGS_OFFSET("pc", pc), +}; + +int ftrace_regs_query_register_offset(const char *name) +{ + for (int i = 0; i < ARRAY_SIZE(fregs_offsets); i++) { + const struct fregs_offset *roff = &fregs_offsets[i]; + if (!strcmp(roff->name, name)) + return roff->offset; + } + + return -EINVAL; +} +#endif + /* * Replace a single instruction, which may be a branch or NOP. * If @validate == true, a replaced instruction is checked against 'old'. @@ -70,9 +112,6 @@ static struct plt_entry *get_ftrace_plt(struct module *mod, unsigned long addr) if (addr == FTRACE_ADDR) return &plt[FTRACE_PLT_IDX]; - if (addr == FTRACE_REGS_ADDR && - IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_REGS)) - return &plt[FTRACE_REGS_PLT_IDX]; #endif return NULL; } @@ -154,25 +193,7 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) return ftrace_modify_code(pc, old, new, true); } -#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS -int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr, - unsigned long addr) -{ - unsigned long pc = rec->ip; - u32 old, new; - - if (!ftrace_find_callable_addr(rec, NULL, &old_addr)) - return -EINVAL; - if (!ftrace_find_callable_addr(rec, NULL, &addr)) - return -EINVAL; - - old = aarch64_insn_gen_branch_imm(pc, old_addr, - AARCH64_INSN_BRANCH_LINK); - new = aarch64_insn_gen_branch_imm(pc, addr, AARCH64_INSN_BRANCH_LINK); - - return ftrace_modify_code(pc, old, new, true); -} - +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_ARGS /* * The compiler has inserted two NOPs before the regular function prologue. * All instrumented functions follow the AAPCS, so x0-x8 and x19-x30 are live, @@ -228,7 +249,7 @@ int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec, * * Note: 'mod' is only set at module load time. */ - if (!IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_REGS) && + if (!IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_ARGS) && IS_ENABLED(CONFIG_ARM64_MODULE_PLTS) && mod) { return aarch64_insn_patch_text_nosync((void *)pc, new); } @@ -246,7 +267,6 @@ void arch_ftrace_update_code(int command) command |= FTRACE_MAY_SLEEP; ftrace_modify_all_code(command); } -#endif /* CONFIG_DYNAMIC_FTRACE */ #ifdef CONFIG_FUNCTION_GRAPH_TRACER /* @@ -277,21 +297,11 @@ void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent, } } -#ifdef CONFIG_DYNAMIC_FTRACE - -#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_ARGS void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct ftrace_regs *fregs) { - /* - * When DYNAMIC_FTRACE_WITH_REGS is selected, `fregs` can never be NULL - * and arch_ftrace_get_regs(fregs) will always give a non-NULL pt_regs - * in which we can safely modify the LR. - */ - struct pt_regs *regs = arch_ftrace_get_regs(fregs); - unsigned long *parent = (unsigned long *)&procedure_link_pointer(regs); - - prepare_ftrace_return(ip, parent, frame_pointer(regs)); + prepare_ftrace_return(ip, &fregs->lr, fregs->fp); } #else /* @@ -323,6 +333,5 @@ int ftrace_disable_ftrace_graph_caller(void) { return ftrace_modify_graph_caller(false); } -#endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ -#endif /* CONFIG_DYNAMIC_FTRACE */ +#endif /* CONFIG_DYNAMIC_FTRACE_WITH_ARGS */ #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |