android_kernel_xiaomi_sm8350/arch/csky/include/asm/ftrace.h
Guo Ren 28bb030f93 csky/ftrace: Add dynamic function tracer (include graph tracer)
Support dynamic ftrace including dynamic graph tracer. Gcc-csky with -pg
will produce call site in every function prologue and we can use these
call site to hook trace function.

gcc with -pg origin call site:
	push	lr
	jbsr	_mcount
	nop32
	nop32

If the (callee - caller)'s offset is in range of bsr instruction, we'll
modify code with:
	push	lr
	bsr	_mcount
	nop32
	nop32
Else if the (callee - caller)'s offset is out of bsr instrunction, we'll
modify code with:
	push	lr
	movih	r26, ...
	ori	r26, ...
	jsr	r26

(r26 is reserved for jsr link reg in csky abiv2 spec.)

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
2019-04-22 13:44:57 +08:00

30 lines
581 B
C

/* SPDX-License-Identifier: GPL-2.0 */
// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
#ifndef __ASM_CSKY_FTRACE_H
#define __ASM_CSKY_FTRACE_H
#define MCOUNT_INSN_SIZE 14
#define HAVE_FUNCTION_GRAPH_FP_TEST
#define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
#define MCOUNT_ADDR ((unsigned long)_mcount)
#ifndef __ASSEMBLY__
extern void _mcount(unsigned long);
extern void ftrace_graph_call(void);
static inline unsigned long ftrace_call_adjust(unsigned long addr)
{
return addr;
}
struct dyn_arch_ftrace {
};
#endif /* !__ASSEMBLY__ */
#endif /* __ASM_CSKY_FTRACE_H */