Commit d3b9dc9d authored by Rabin Vincent's avatar Rabin Vincent
Browse files

ARM: ftrace: use gas macros to avoid code duplication 



Use assembler macros to avoid copy/pasting code between the
implementations of the two variants of the mcount call.

Signed-off-by: default avatarRabin Vincent <rabin@rab.in>
parent 61b5cb1c

arch/arm/kernel/entry-common.S

+80 −66
Original line number Diff line number Diff line
@@ -141,98 +141,112 @@ ENDPROC(ret_from_fork) 
#endif

#endif



#ifdef CONFIG_DYNAMIC_FTRACE

ENTRY(__gnu_mcount_nc)

	mov	ip, lr

	ldmia	sp!, {lr}

	mov	pc, ip

ENDPROC(__gnu_mcount_nc)

.macro __mcount suffix

	mcount_enter

	ldr	r0, =ftrace_trace_function

	ldr	r2, [r0]

	adr	r0, .Lftrace_stub

	cmp	r0, r2

	bne	1f

	mcount_exit



ENTRY(ftrace_caller)

	stmdb	sp!, {r0-r3, lr}

	mov	r0, lr

1: 	mcount_get_lr	r1			@ lr of instrumented func

	mov	r0, lr				@ instrumented function

	sub	r0, r0, #MCOUNT_INSN_SIZE

	adr	lr, BSYM(2f)

	mov	pc, r2

2:	mcount_exit

.endm



.macro __ftrace_caller suffix

	mcount_enter



	mcount_get_lr	r1			@ lr of instrumented func

	mov	r0, lr				@ instrumented function

	sub	r0, r0, #MCOUNT_INSN_SIZE

	ldr	r1, [sp, #20]



	.global	ftrace_call

ftrace_call:

	.globl ftrace_call\suffix

ftrace_call\suffix:

	bl	ftrace_stub

	ldmia	sp!, {r0-r3, ip, lr}

	mov	pc, ip

ENDPROC(ftrace_caller)



	mcount_exit

.endm



#ifdef CONFIG_OLD_MCOUNT

/*

 * mcount

 */



.macro mcount_enter

	stmdb	sp!, {r0-r3, lr}

.endm



.macro mcount_get_lr reg

	ldr	\reg, [fp, #-4]

.endm



.macro mcount_exit

	ldr	lr, [fp, #-4]

	ldmia	sp!, {r0-r3, pc}

.endm



ENTRY(mcount)

#ifdef CONFIG_DYNAMIC_FTRACE

	stmdb	sp!, {lr}

	ldr	lr, [fp, #-4]

	ldmia	sp!, {pc}

#else

	__mcount _old

#endif

ENDPROC(mcount)



#ifdef CONFIG_DYNAMIC_FTRACE

ENTRY(ftrace_caller_old)

	stmdb	sp!, {r0-r3, lr}

	ldr	r1, [fp, #-4]

	mov	r0, lr

	sub	r0, r0, #MCOUNT_INSN_SIZE



	.globl ftrace_call_old

ftrace_call_old:

	bl	ftrace_stub

	ldr	lr, [fp, #-4]			@ restore lr

	ldmia	sp!, {r0-r3, pc}

	__ftrace_caller _old

ENDPROC(ftrace_caller_old)

#endif



#else

.purgem mcount_enter

.purgem mcount_get_lr

.purgem mcount_exit

#endif



ENTRY(__gnu_mcount_nc)

/*

 * __gnu_mcount_nc

 */



.macro mcount_enter

	stmdb	sp!, {r0-r3, lr}

	ldr	r0, =ftrace_trace_function

	ldr	r2, [r0]

	adr	r0, .Lftrace_stub

	cmp	r0, r2

	bne	gnu_trace

.endm



.macro mcount_get_lr reg

	ldr	\reg, [sp, #20]

.endm



.macro mcount_exit

	ldmia	sp!, {r0-r3, ip, lr}

	mov	pc, ip

.endm



gnu_trace:

	ldr	r1, [sp, #20]			@ lr of instrumented routine

	mov	r0, lr

	sub	r0, r0, #MCOUNT_INSN_SIZE

	adr	lr, BSYM(1f)

	mov	pc, r2

1:

	ldmia	sp!, {r0-r3, ip, lr}

ENTRY(__gnu_mcount_nc)

#ifdef CONFIG_DYNAMIC_FTRACE

	mov	ip, lr

	ldmia	sp!, {lr}

	mov	pc, ip

#else

	__mcount

#endif

ENDPROC(__gnu_mcount_nc)



#ifdef CONFIG_OLD_MCOUNT

/*

 * This is under an ifdef in order to force link-time errors for people trying

 * to build with !FRAME_POINTER with a GCC which doesn't use the new-style

 * mcount.

 */

ENTRY(mcount)

	stmdb	sp!, {r0-r3, lr}

	ldr	r0, =ftrace_trace_function

	ldr	r2, [r0]

	adr	r0, ftrace_stub

	cmp	r0, r2

	bne	trace

	ldr	lr, [fp, #-4]			@ restore lr

	ldmia	sp!, {r0-r3, pc}



trace:

	ldr	r1, [fp, #-4]			@ lr of instrumented routine

	mov	r0, lr

	sub	r0, r0, #MCOUNT_INSN_SIZE

	mov	lr, pc

	mov	pc, r2

	ldr	lr, [fp, #-4]			@ restore lr

	ldmia	sp!, {r0-r3, pc}

ENDPROC(mcount)

#ifdef CONFIG_DYNAMIC_FTRACE

ENTRY(ftrace_caller)

	__ftrace_caller

ENDPROC(ftrace_caller)

#endif



#endif /* CONFIG_DYNAMIC_FTRACE */

.purgem mcount_enter

.purgem mcount_get_lr

.purgem mcount_exit



ENTRY(ftrace_stub)

.Lftrace_stub: