diff options
| -rw-r--r-- | arch/csky/Kconfig | 1 | ||||
| -rw-r--r-- | arch/csky/abiv2/mcount.S | 116 | ||||
| -rw-r--r-- | arch/csky/include/asm/ftrace.h | 6 | ||||
| -rw-r--r-- | arch/csky/kernel/ftrace.c | 48 |
4 files changed, 151 insertions, 20 deletions
diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig index 0b9a290c0157..6e814772d72e 100644 --- a/arch/csky/Kconfig +++ b/arch/csky/Kconfig @@ -30,6 +30,7 @@ config CSKY select GENERIC_SMP_IDLE_THREAD select HAVE_ARCH_TRACEHOOK select HAVE_FUNCTION_TRACER + select HAVE_FUNCTION_GRAPH_TRACER select HAVE_GENERIC_DMA_COHERENT select HAVE_KERNEL_GZIP select HAVE_KERNEL_LZO diff --git a/arch/csky/abiv2/mcount.S b/arch/csky/abiv2/mcount.S index 73377d5ddd18..c633379956f5 100644 --- a/arch/csky/abiv2/mcount.S +++ b/arch/csky/abiv2/mcount.S @@ -2,23 +2,123 @@ // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. #include <linux/linkage.h> +#include <asm/ftrace.h> -ENTRY (_mcount) - subi sp, 20 +/* + * csky-gcc with -pg will put the following asm after prologue: + * push r15 + * jsri _mcount + * + * stack layout after mcount_enter in _mcount(): + * + * current sp => 0:+-------+ + * | a0-a3 | -> must save all argument regs + * +16:+-------+ + * | lr | -> _mcount lr (instrumente function's pc) + * +20:+-------+ + * | fp=r8 | -> instrumented function fp + * +24:+-------+ + * | plr | -> instrumented function lr (parent's pc) + * +-------+ + */ + +.macro mcount_enter + subi sp, 24 stw a0, (sp, 0) stw a1, (sp, 4) stw a2, (sp, 8) stw a3, (sp, 12) stw lr, (sp, 16) - mov a1, lr - ldw a0, (sp, 20) - jsri csky_mcount + stw r8, (sp, 20) +.endm + +.macro mcount_exit ldw a0, (sp, 0) ldw a1, (sp, 4) ldw a2, (sp, 8) ldw a3, (sp, 12) ldw t1, (sp, 16) - ldw lr, (sp, 20) - addi sp, 24 + ldw r8, (sp, 20) + ldw lr, (sp, 24) + addi sp, 28 jmp t1 -END (_mcount) +.endm + +.macro save_return_regs + subi sp, 16 + stw a0, (sp, 0) + stw a1, (sp, 4) + stw a2, (sp, 8) + stw a3, (sp, 12) +.endm + +.macro restore_return_regs + mov lr, a0 + ldw a0, (sp, 0) + ldw a1, (sp, 4) + ldw a2, (sp, 8) + ldw a3, (sp, 12) + addi sp, 16 +.endm + +ENTRY(ftrace_stub) + jmp lr +END(ftrace_stub) + +ENTRY(_mcount) + mcount_enter + + /* r26 is link register, only used with jsri translation */ + lrw r26, ftrace_trace_function + ldw r26, (r26, 0) + lrw a1, ftrace_stub + cmpne r26, a1 + bf skip_ftrace + + mov a0, lr + subi a0, MCOUNT_INSN_SIZE + ldw a1, (sp, 24) + + jsr r26 + +#ifndef CONFIG_FUNCTION_GRAPH_TRACER +skip_ftrace: + mcount_exit +#else +skip_ftrace: + lrw a0, ftrace_graph_return + ldw a0, (a0, 0) + lrw a1, ftrace_stub + cmpne a0, a1 + bt ftrace_graph_caller + + lrw a0, ftrace_graph_entry + ldw a0, (a0, 0) + lrw a1, ftrace_graph_entry_stub + cmpne a0, a1 + bt ftrace_graph_caller + + mcount_exit +#endif +END(_mcount) + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +ENTRY(ftrace_graph_caller) + mov a0, sp + addi a0, 24 + ldw a1, (sp, 16) + subi a1, MCOUNT_INSN_SIZE + mov a2, r8 + lrw r26, prepare_ftrace_return + jsr r26 + mcount_exit +END(ftrace_graph_caller) + +ENTRY(return_to_handler) + save_return_regs + mov a0, r8 + jsri ftrace_return_to_handler + restore_return_regs + jmp lr +END(return_to_handler) +#endif diff --git a/arch/csky/include/asm/ftrace.h b/arch/csky/include/asm/ftrace.h index 1d22a1787b8b..7547c45312a8 100644 --- a/arch/csky/include/asm/ftrace.h +++ b/arch/csky/include/asm/ftrace.h @@ -4,6 +4,10 @@ #ifndef __ASM_CSKY_FTRACE_H #define __ASM_CSKY_FTRACE_H -extern void _mcount(unsigned long from_pc); +#define MCOUNT_INSN_SIZE 4 + +#define HAVE_FUNCTION_GRAPH_FP_TEST + +#define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR #endif /* __ASM_CSKY_FTRACE_H */ diff --git a/arch/csky/kernel/ftrace.c b/arch/csky/kernel/ftrace.c index ad054f7190f9..274c431f1810 100644 --- a/arch/csky/kernel/ftrace.c +++ b/arch/csky/kernel/ftrace.c @@ -4,21 +4,47 @@ #include <linux/ftrace.h> #include <linux/uaccess.h> -extern void (*ftrace_trace_function)(unsigned long, unsigned long, - struct ftrace_ops*, struct pt_regs*); +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr, + unsigned long frame_pointer) +{ + unsigned long return_hooker = (unsigned long)&return_to_handler; + unsigned long old; + if (unlikely(atomic_read(¤t->tracing_graph_pause))) + return; -noinline void __naked ftrace_stub(unsigned long ip, unsigned long parent_ip, - struct ftrace_ops *op, struct pt_regs *regs) -{ - asm volatile ("\n"); -} + old = *parent; -noinline void csky_mcount(unsigned long from_pc, unsigned long self_pc) -{ - if (ftrace_trace_function != ftrace_stub) - ftrace_trace_function(self_pc, from_pc, NULL, NULL); + if (!function_graph_enter(old, self_addr, + *(unsigned long *)frame_pointer, parent)) { + /* + * For csky-gcc function has sub-call: + * subi sp, sp, 8 + * stw r8, (sp, 0) + * mov r8, sp + * st.w r15, (sp, 0x4) + * push r15 + * jl _mcount + * We only need set *parent for resume + * + * For csky-gcc function has no sub-call: + * subi sp, sp, 4 + * stw r8, (sp, 0) + * mov r8, sp + * push r15 + * jl _mcount + * We need set *parent and *(frame_pointer + 4) for resume, + * because lr is resumed twice. + */ + *parent = return_hooker; + frame_pointer += 4; + if (*(unsigned long *)frame_pointer == old) + *(unsigned long *)frame_pointer = return_hooker; + } } +#endif /* _mcount is defined in abi's mcount.S */ +extern void _mcount(void); EXPORT_SYMBOL(_mcount); |