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| /*
| * MIPS specific _mcount support
| *
| * This file is subject to the terms and conditions of the GNU General Public
| * License. See the file "COPYING" in the main directory of this archive for
| * more details.
| *
| * Copyright (C) 2009 Lemote Inc. & DSLab, Lanzhou University, China
| * Copyright (C) 2010 DSLab, Lanzhou University, China
| * Author: Wu Zhangjin <wuzhangjin@gmail.com>
| */
|
| #include <asm/export.h>
| #include <asm/regdef.h>
| #include <asm/stackframe.h>
| #include <asm/ftrace.h>
|
| .text
| .set noreorder
| .set noat
|
| .macro MCOUNT_SAVE_REGS
| PTR_SUBU sp, PT_SIZE
| PTR_S ra, PT_R31(sp)
| PTR_S AT, PT_R1(sp)
| PTR_S a0, PT_R4(sp)
| PTR_S a1, PT_R5(sp)
| PTR_S a2, PT_R6(sp)
| PTR_S a3, PT_R7(sp)
| #ifdef CONFIG_64BIT
| PTR_S a4, PT_R8(sp)
| PTR_S a5, PT_R9(sp)
| PTR_S a6, PT_R10(sp)
| PTR_S a7, PT_R11(sp)
| #endif
| .endm
|
| .macro MCOUNT_RESTORE_REGS
| PTR_L ra, PT_R31(sp)
| PTR_L AT, PT_R1(sp)
| PTR_L a0, PT_R4(sp)
| PTR_L a1, PT_R5(sp)
| PTR_L a2, PT_R6(sp)
| PTR_L a3, PT_R7(sp)
| #ifdef CONFIG_64BIT
| PTR_L a4, PT_R8(sp)
| PTR_L a5, PT_R9(sp)
| PTR_L a6, PT_R10(sp)
| PTR_L a7, PT_R11(sp)
| #endif
| PTR_ADDIU sp, PT_SIZE
| .endm
|
| .macro RETURN_BACK
| jr ra
| move ra, AT
| .endm
|
| /*
| * The -mmcount-ra-address option of gcc 4.5 uses register $12 to pass
| * the location of the parent's return address.
| */
| #define MCOUNT_RA_ADDRESS_REG $12
|
| #ifdef CONFIG_DYNAMIC_FTRACE
|
| NESTED(ftrace_caller, PT_SIZE, ra)
| .globl _mcount
| _mcount:
| EXPORT_SYMBOL(_mcount)
| b ftrace_stub
| #ifdef CONFIG_32BIT
| addiu sp,sp,8
| #else
| nop
| #endif
|
| /* When tracing is activated, it calls ftrace_caller+8 (aka here) */
| MCOUNT_SAVE_REGS
| #ifdef KBUILD_MCOUNT_RA_ADDRESS
| PTR_S MCOUNT_RA_ADDRESS_REG, PT_R12(sp)
| #endif
|
| PTR_SUBU a0, ra, 8 /* arg1: self address */
| PTR_LA t1, _stext
| sltu t2, a0, t1 /* t2 = (a0 < _stext) */
| PTR_LA t1, _etext
| sltu t3, t1, a0 /* t3 = (a0 > _etext) */
| or t1, t2, t3
| beqz t1, ftrace_call
| nop
| #if defined(KBUILD_MCOUNT_RA_ADDRESS) && defined(CONFIG_32BIT)
| PTR_SUBU a0, a0, 16 /* arg1: adjust to module's recorded callsite */
| #else
| PTR_SUBU a0, a0, 12
| #endif
|
| .globl ftrace_call
| ftrace_call:
| nop /* a placeholder for the call to a real tracing function */
| move a1, AT /* arg2: parent's return address */
|
| #ifdef CONFIG_FUNCTION_GRAPH_TRACER
| .globl ftrace_graph_call
| ftrace_graph_call:
| nop
| nop
| #endif
|
| MCOUNT_RESTORE_REGS
| .globl ftrace_stub
| ftrace_stub:
| RETURN_BACK
| END(ftrace_caller)
|
| #else /* ! CONFIG_DYNAMIC_FTRACE */
|
| NESTED(_mcount, PT_SIZE, ra)
| EXPORT_SYMBOL(_mcount)
| PTR_LA t1, ftrace_stub
| PTR_L t2, ftrace_trace_function /* Prepare t2 for (1) */
| beq t1, t2, fgraph_trace
| nop
|
| MCOUNT_SAVE_REGS
|
| move a0, ra /* arg1: self return address */
| jalr t2 /* (1) call *ftrace_trace_function */
| move a1, AT /* arg2: parent's return address */
|
| MCOUNT_RESTORE_REGS
|
| fgraph_trace:
| #ifdef CONFIG_FUNCTION_GRAPH_TRACER
| PTR_LA t1, ftrace_stub
| PTR_L t3, ftrace_graph_return
| bne t1, t3, ftrace_graph_caller
| nop
| PTR_LA t1, ftrace_graph_entry_stub
| PTR_L t3, ftrace_graph_entry
| bne t1, t3, ftrace_graph_caller
| nop
| #endif
|
| #ifdef CONFIG_32BIT
| addiu sp, sp, 8
| #endif
|
| .globl ftrace_stub
| ftrace_stub:
| RETURN_BACK
| END(_mcount)
|
| #endif /* ! CONFIG_DYNAMIC_FTRACE */
|
| #ifdef CONFIG_FUNCTION_GRAPH_TRACER
|
| NESTED(ftrace_graph_caller, PT_SIZE, ra)
| #ifndef CONFIG_DYNAMIC_FTRACE
| MCOUNT_SAVE_REGS
| #endif
|
| /* arg1: Get the location of the parent's return address */
| #ifdef KBUILD_MCOUNT_RA_ADDRESS
| #ifdef CONFIG_DYNAMIC_FTRACE
| PTR_L a0, PT_R12(sp)
| #else
| move a0, MCOUNT_RA_ADDRESS_REG
| #endif
| bnez a0, 1f /* non-leaf func: stored in MCOUNT_RA_ADDRESS_REG */
| nop
| #endif
| PTR_LA a0, PT_R1(sp) /* leaf func: the location in current stack */
| 1:
|
| /* arg2: Get self return address */
| #ifdef CONFIG_DYNAMIC_FTRACE
| PTR_L a1, PT_R31(sp)
| #else
| move a1, ra
| #endif
|
| /* arg3: Get frame pointer of current stack */
| #ifdef CONFIG_64BIT
| PTR_LA a2, PT_SIZE(sp)
| #else
| PTR_LA a2, (PT_SIZE+8)(sp)
| #endif
|
| jal prepare_ftrace_return
| nop
| MCOUNT_RESTORE_REGS
| #ifndef CONFIG_DYNAMIC_FTRACE
| #ifdef CONFIG_32BIT
| addiu sp, sp, 8
| #endif
| #endif
| RETURN_BACK
| END(ftrace_graph_caller)
|
| .align 2
| .globl return_to_handler
| return_to_handler:
| PTR_SUBU sp, PT_SIZE
| PTR_S v0, PT_R2(sp)
|
| jal ftrace_return_to_handler
| PTR_S v1, PT_R3(sp)
|
| /* restore the real parent address: v0 -> ra */
| move ra, v0
|
| PTR_L v0, PT_R2(sp)
| PTR_L v1, PT_R3(sp)
| jr ra
| PTR_ADDIU sp, PT_SIZE
| #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
|
| .set at
| .set reorder
|
|
