Commit 7f08ae53 authored by Mark Rutland's avatar Mark Rutland
Browse files

arm64: ftrace: minimize ifdeffery 



Now that we no longer refer to mod->arch.ftrace_trampolines in the body
of ftrace_make_call(), we can use IS_ENABLED() rather than ifdeffery,
and make the code easier to follow. Likewise in ftrace_make_nop().

Let's do so.

Signed-off-by: default avatarMark Rutland <mark.rutland@arm.com>
Reviewed-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: default avatarTorsten Duwe <duwe@suse.de>
Tested-by: default avatarAmit Daniel Kachhap <amit.kachhap@arm.com>
Tested-by: default avatarTorsten Duwe <duwe@suse.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
parent 3b23e499

arch/arm64/kernel/ftrace.c

+8 −10
Original line number Diff line number Diff line
@@ -62,18 +62,18 @@ int ftrace_update_ftrace_func(ftrace_func_t func) 
	return ftrace_modify_code(pc, 0, new, false);

}



#ifdef CONFIG_ARM64_MODULE_PLTS

static struct plt_entry *get_ftrace_plt(struct module *mod, unsigned long addr)

{

#ifdef CONFIG_ARM64_MODULE_PLTS

	struct plt_entry *plt = mod->arch.ftrace_trampolines;



	if (addr == FTRACE_ADDR)

		return &plt[FTRACE_PLT_IDX];

	if (addr == FTRACE_REGS_ADDR && IS_ENABLED(CONFIG_FTRACE_WITH_REGS))

		return &plt[FTRACE_REGS_PLT_IDX];

#endif

	return NULL;

}

#endif



/*

 * Turn on the call to ftrace_caller() in instrumented function
@@ -85,10 +85,12 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) 
	long offset = (long)pc - (long)addr;



	if (offset < -SZ_128M || offset >= SZ_128M) {

#ifdef CONFIG_ARM64_MODULE_PLTS

		struct module *mod;

		struct plt_entry *plt;



		if (!IS_ENABLED(CONFIG_ARM64_MODULE_PLTS))

			return -EINVAL;



		/*

		 * On kernels that support module PLTs, the offset between the

		 * branch instruction and its target may legally exceed the
@@ -113,9 +115,6 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) 
		}



		addr = (unsigned long)plt;

#else /* CONFIG_ARM64_MODULE_PLTS */

		return -EINVAL;

#endif /* CONFIG_ARM64_MODULE_PLTS */

	}



	old = aarch64_insn_gen_nop();
@@ -185,9 +184,11 @@ int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec, 
	long offset = (long)pc - (long)addr;



	if (offset < -SZ_128M || offset >= SZ_128M) {

#ifdef CONFIG_ARM64_MODULE_PLTS

		u32 replaced;



		if (!IS_ENABLED(CONFIG_ARM64_MODULE_PLTS))

			return -EINVAL;



		/*

		 * 'mod' is only set at module load time, but if we end up

		 * dealing with an out-of-range condition, we can assume it
@@ -218,9 +219,6 @@ int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec, 
			return -EINVAL;



		validate = false;

#else /* CONFIG_ARM64_MODULE_PLTS */

		return -EINVAL;

#endif /* CONFIG_ARM64_MODULE_PLTS */

	} else {

		old = aarch64_insn_gen_branch_imm(pc, addr,

						  AARCH64_INSN_BRANCH_LINK);

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