LoongArch: Add kprobes on ftrace support
Add kprobe_ftrace_handler() and arch_prepare_kprobe_ftrace() to support
kprobes on ftrace, the code is similar with x86 and riscv.
Here is a simple example:
# echo 'p:myprobe kernel_clone' > /sys/kernel/debug/tracing/kprobe_events
# echo 'r:myretprobe kernel_clone $retval' >> /sys/kernel/debug/tracing/kprobe_events
# echo 1 > /sys/kernel/debug/tracing/events/kprobes/myprobe/enable
# echo 1 > /sys/kernel/debug/tracing/events/kprobes/myretprobe/enable
# echo 1 > /sys/kernel/debug/tracing/tracing_on
# cat /sys/kernel/debug/tracing/trace
# tracer: nop
#
# entries-in-buffer/entries-written: 2/2 #P:4
#
# _-----=> irqs-off/BH-disabled
# / _----=> need-resched
# | / _---=> hardirq/softirq
# || / _--=> preempt-depth
# ||| / _-=> migrate-disable
# |||| / delay
# TASK-PID CPU# ||||| TIMESTAMP FUNCTION
# | | | ||||| | |
bash-488 [002] ..... 2041.190681: myprobe: (kernel_clone+0x0/0x40c)
bash-488 [002] ..... 2041.190788: myretprobe: (__do_sys_clone+0x84/0xb8 <- kernel_clone) arg1=0x200
Tested-by: Jeff Xie <xiehuan09@gmail.com>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
index d90bb47..7fd5125 100644
--- a/arch/loongarch/Kconfig
+++ b/arch/loongarch/Kconfig
@@ -107,6 +107,7 @@
select HAVE_IRQ_EXIT_ON_IRQ_STACK
select HAVE_IRQ_TIME_ACCOUNTING
select HAVE_KPROBES
+ select HAVE_KPROBES_ON_FTRACE
select HAVE_KRETPROBES
select HAVE_MOD_ARCH_SPECIFIC
select HAVE_NMI
