ftrace kprobe函数内部插入跟踪点

Disassembly of section .text:

0000000000000000 <.xx_request>:
   0: 7c 08 02 a6     mflr    r0
   ...
 12c: e9 28 00 08     ld      r9,8(r8)
 130: 7c 64 1b 78     mr      r4,r3
 134: 7c 69 3a 14 add r3,r9,r7
 138: 48 00 00 01 bl 138 <.xx_request+0x138> 【写,】   【这里因为是模块内函数，对应实际-y编译是调用的  4b b3 9b 51 bl c000000000039680 <.memcpy>】

打印memcpy的三个参数
echo 'p:myprobe xx_request+0x138 %r3 %r4 %r5' >> /sys/kernel/debug/tracing/kprobe_events


/sys/kernel/debug/tracing/events # cat ../trace
# tracer: nop
#
# entries-in-buffer/entries-written: 81/81   #P:8
#
#                              _-----=> irqs-off
#                             / _----=> need-resched
# |/ _-----=> need-resched_lazy
# || / _---=> hardirq/softirq
# ||| / _--=> preempt-depth
# |||| / _-=> preempt-lazy-depth
# ||||| / _-=> migrate-disable
# |||||| /    delay
#           TASK-PID   CPU# ||||||| TIMESTAMP  FUNCTION
# | | | ||||||| | |
    cqfs_crc_ppc-1782 [005] d...2.. 12723.369397: myprobe: (.xx_request+0x138/0x22c [xxdisk]) arg1=0x800008008910dc00 arg2=0xc000000000d26800 arg3=0x800
    kworker/5:1H-1671 [005] d...2.. 12723.377451: myprobe: (.xx_request+0x138/0x22c [xxdisk]) arg1=0x8000080088c92000 arg2=0xc000000079c70000 arg3=0x400
    kworker/5:1H-1671 [005] d...2.. 12723.377461: myprobe: (.xx_request+0x138/0x22c [xxdisk]) arg1=0x8000080088c92400 arg2=0xc000000079c53000 arg3=0x400
    kworker/5:1H-1671 [005] d...2.. 12723.377468: myprobe: (.xx_request+0x138/0x22c [xxdisk]) arg1=0x8000080088c92800 arg2=0xc000000003ebd000 arg3=0x400