Commit af8b9f35 authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/ftrace: Minimise number of #ifdefs 



A lot of #ifdefs can be replaced by IS_ENABLED()

Do so.

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Fold in changes suggested by Naveen and Christophe on list]
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/18ce6708d6f8c71d87436f9c6019f04df4125128.1652074503.git.christophe.leroy@csgroup.eu
parent b97d0e3d

arch/powerpc/include/asm/code-patching.h

+0 −2
Original line number Diff line number Diff line
@@ -219,7 +219,6 @@ static inline unsigned long ppc_kallsyms_lookup_name(const char *name) 
	return addr;

}



#ifdef CONFIG_PPC64

/*

 * Some instruction encodings commonly used in dynamic ftracing

 * and function live patching.
@@ -236,6 +235,5 @@ static inline unsigned long ppc_kallsyms_lookup_name(const char *name) 


/* usually preceded by a mflr r0 */

#define PPC_INST_STD_LR		PPC_RAW_STD(_R0, _R1, PPC_LR_STKOFF)

#endif /* CONFIG_PPC64 */



#endif /* _ASM_POWERPC_CODE_PATCHING_H */

arch/powerpc/include/asm/module.h

+0 −2
Original line number Diff line number Diff line
@@ -41,9 +41,7 @@ struct mod_arch_specific { 


#ifdef CONFIG_DYNAMIC_FTRACE

	unsigned long tramp;

#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS

	unsigned long tramp_regs;

#endif

#endif



	/* List of BUG addresses, source line numbers and filenames */

arch/powerpc/kernel/trace/ftrace.c

+85 −90
Original line number Diff line number Diff line
@@ -150,11 +150,7 @@ __ftrace_make_nop(struct module *mod, 
		return -EINVAL;

	}



	/* When using -mprofile-kernel or PPC32 there is no load to jump over */

	pop = ppc_inst(PPC_RAW_NOP());



#ifdef CONFIG_PPC64

#ifdef CONFIG_MPROFILE_KERNEL

	if (IS_ENABLED(CONFIG_MPROFILE_KERNEL)) {

		if (copy_inst_from_kernel_nofault(&op, (void *)(ip - 4))) {

			pr_err("Fetching instruction at %lx failed.\n", ip - 4);

			return -EFAULT;
@@ -167,23 +163,7 @@ __ftrace_make_nop(struct module *mod, 
			       ppc_inst_as_str(op));

			return -EINVAL;

		}

#else

	/*

	 * Our original call site looks like:

	 *

	 * bl <tramp>

	 * ld r2,XX(r1)

	 *

	 * Milton Miller pointed out that we can not simply nop the branch.

	 * If a task was preempted when calling a trace function, the nops

	 * will remove the way to restore the TOC in r2 and the r2 TOC will

	 * get corrupted.

	 *

	 * Use a b +8 to jump over the load.

	 */



	pop = ppc_inst(PPC_RAW_BRANCH(8));	/* b +8 */



	} else if (IS_ENABLED(CONFIG_PPC64)) {

		/*

		 * Check what is in the next instruction. We can see ld r2,40(r1), but

		 * on first pass after boot we will see mflr r0.
@@ -197,8 +177,27 @@ __ftrace_make_nop(struct module *mod, 
			pr_err("Expected %08lx found %s\n", PPC_INST_LD_TOC, ppc_inst_as_str(op));

			return -EINVAL;

		}

#endif /* CONFIG_MPROFILE_KERNEL */

#endif /* PPC64 */

	}



	/*

	 * When using -mprofile-kernel or PPC32 there is no load to jump over.

	 *

	 * Otherwise our original call site looks like:

	 *

	 * bl <tramp>

	 * ld r2,XX(r1)

	 *

	 * Milton Miller pointed out that we can not simply nop the branch.

	 * If a task was preempted when calling a trace function, the nops

	 * will remove the way to restore the TOC in r2 and the r2 TOC will

	 * get corrupted.

	 *

	 * Use a b +8 to jump over the load.

	 */

	if (IS_ENABLED(CONFIG_MPROFILE_KERNEL) || IS_ENABLED(CONFIG_PPC32))

		pop = ppc_inst(PPC_RAW_NOP());

	else

		pop = ppc_inst(PPC_RAW_BRANCH(8));	/* b +8 */



	if (patch_instruction((u32 *)ip, pop)) {

		pr_err("Patching NOP failed.\n");
@@ -207,6 +206,11 @@ __ftrace_make_nop(struct module *mod, 


	return 0;

}

#else

static int __ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec, unsigned long addr)

{

	return 0;

}

#endif /* CONFIG_MODULES */



static unsigned long find_ftrace_tramp(unsigned long ip)
@@ -279,11 +283,11 @@ static int setup_mcount_compiler_tramp(unsigned long tramp) 
	}



	/* Let's re-write the tramp to go to ftrace_[regs_]caller */

#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS

	if (IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_REGS))

		ptr = ppc_global_function_entry((void *)ftrace_regs_caller);

#else

	else

		ptr = ppc_global_function_entry((void *)ftrace_caller);

#endif



	if (patch_branch((u32 *)tramp, ptr, 0)) {

		pr_debug("REL24 out of range!\n");

		return -1;
@@ -352,10 +356,12 @@ int ftrace_make_nop(struct module *mod, 
		old = ftrace_call_replace(ip, addr, 1);

		new = ppc_inst(PPC_RAW_NOP());

		return ftrace_modify_code(ip, old, new);

	} else if (core_kernel_text(ip))

	} else if (core_kernel_text(ip)) {

		return __ftrace_make_nop_kernel(rec, addr);

	} else if (!IS_ENABLED(CONFIG_MODULES)) {

		return -EINVAL;

	}



#ifdef CONFIG_MODULES

	/*

	 * Out of range jumps are called from modules.

	 * We should either already have a pointer to the module
@@ -378,10 +384,6 @@ int ftrace_make_nop(struct module *mod, 
		mod = rec->arch.mod;



	return __ftrace_make_nop(mod, rec, addr);

#else

	/* We should not get here without modules */

	return -EINVAL;

#endif /* CONFIG_MODULES */

}



#ifdef CONFIG_MODULES
@@ -411,10 +413,9 @@ __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) 
	if (copy_inst_from_kernel_nofault(op, ip))

		return -EFAULT;



#ifdef CONFIG_PPC64_ELF_ABI_V1

	if (copy_inst_from_kernel_nofault(op + 1, ip + 4))

	if (IS_ENABLED(CONFIG_PPC64_ELF_ABI_V1) &&

	    copy_inst_from_kernel_nofault(op + 1, ip + 4))

		return -EFAULT;

#endif



	if (!expected_nop_sequence(ip, op[0], op[1])) {

		pr_err("Unexpected call sequence at %p: %s %s\n",
@@ -423,20 +424,15 @@ __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) 
	}



	/* If we never set up ftrace trampoline(s), then bail */

#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS

	if (!mod->arch.tramp || !mod->arch.tramp_regs) {

#else

	if (!mod->arch.tramp) {

#endif

	if (!mod->arch.tramp ||

	    (IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_REGS) && !mod->arch.tramp_regs)) {

		pr_err("No ftrace trampoline\n");

		return -EINVAL;

	}



#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS

	if (rec->flags & FTRACE_FL_REGS)

	if (IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_REGS) && rec->flags & FTRACE_FL_REGS)

		tramp = mod->arch.tramp_regs;

	else

#endif

		tramp = mod->arch.tramp;



	if (module_trampoline_target(mod, tramp, &ptr)) {
@@ -460,6 +456,11 @@ __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) 


	return 0;

}

#else

static int __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)

{

	return 0;

}

#endif /* CONFIG_MODULES */



static int __ftrace_make_call_kernel(struct dyn_ftrace *rec, unsigned long addr)
@@ -472,16 +473,12 @@ static int __ftrace_make_call_kernel(struct dyn_ftrace *rec, unsigned long addr) 
	entry = ppc_global_function_entry((void *)ftrace_caller);

	ptr = ppc_global_function_entry((void *)addr);



	if (ptr != entry) {

#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS

	if (ptr != entry && IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_REGS))

		entry = ppc_global_function_entry((void *)ftrace_regs_caller);



	if (ptr != entry) {

#endif

		pr_err("Unknown ftrace addr to patch: %ps\n", (void *)ptr);

		return -EINVAL;

#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS

		}

#endif

	}



	/* Make sure we have a nop */
@@ -524,10 +521,13 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) 
		old = ppc_inst(PPC_RAW_NOP());

		new = ftrace_call_replace(ip, addr, 1);

		return ftrace_modify_code(ip, old, new);

	} else if (core_kernel_text(ip))

	} else if (core_kernel_text(ip)) {

		return __ftrace_make_call_kernel(rec, addr);

	} else if (!IS_ENABLED(CONFIG_MODULES)) {

		/* We should not get here without modules */

		return -EINVAL;

	}



#ifdef CONFIG_MODULES

	/*

	 * Out of range jumps are called from modules.

	 * Being that we are converting from nop, it had better
@@ -539,10 +539,6 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) 
	}



	return __ftrace_make_call(rec, addr);

#else

	/* We should not get here without modules */

	return -EINVAL;

#endif /* CONFIG_MODULES */

}



#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
@@ -633,6 +629,11 @@ __ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr, 


	return 0;

}

#else

static int __ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr, unsigned long addr)

{

	return 0;

}

#endif



int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
@@ -657,9 +658,11 @@ int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr, 
		 * variant, so there is nothing to do here

		 */

		return 0;

	} else if (!IS_ENABLED(CONFIG_MODULES)) {

		/* We should not get here without modules */

		return -EINVAL;

	}



#ifdef CONFIG_MODULES

	/*

	 * Out of range jumps are called from modules.

	 */
@@ -669,10 +672,6 @@ int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr, 
	}



	return __ftrace_modify_call(rec, old_addr, addr);

#else

	/* We should not get here without modules */

	return -EINVAL;

#endif /* CONFIG_MODULES */

}

#endif
@@ -686,15 +685,13 @@ int ftrace_update_ftrace_func(ftrace_func_t func) 
	new = ftrace_call_replace(ip, (unsigned long)func, 1);

	ret = ftrace_modify_code(ip, old, new);



#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS

	/* Also update the regs callback function */

	if (!ret) {

	if (IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_REGS) && !ret) {

		ip = (unsigned long)(&ftrace_regs_call);

		old = ppc_inst_read((u32 *)&ftrace_regs_call);

		new = ftrace_call_replace(ip, (unsigned long)func, 1);

		ret = ftrace_modify_code(ip, old, new);

	}

#endif



	return ret;

}
@@ -724,12 +721,15 @@ int __init ftrace_dyn_arch_init(void) 
		PPC_RAW_MTCTR(_R12),

		PPC_RAW_BCTR()

	};

#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS

	unsigned long addr = ppc_global_function_entry((void *)ftrace_regs_caller);

#else

	unsigned long addr = ppc_global_function_entry((void *)ftrace_caller);

#endif

	long reladdr = addr - kernel_toc_addr();

	unsigned long addr;

	long reladdr;



	if (IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_REGS))

		addr = ppc_global_function_entry((void *)ftrace_regs_caller);

	else

		addr = ppc_global_function_entry((void *)ftrace_caller);



	reladdr = addr - kernel_toc_addr();



	if (reladdr >= SZ_2G || reladdr < -(long)SZ_2G) {

		pr_err("Address of %ps out of range of kernel_toc.\n",
@@ -746,11 +746,6 @@ int __init ftrace_dyn_arch_init(void) 


	return 0;

}

#else

int __init ftrace_dyn_arch_init(void)

{

	return 0;

}

#endif



#ifdef CONFIG_FUNCTION_GRAPH_TRACER