Re: [PATCH v2] riscv: add tracepoints for page fault

[Zhu Hengbo]

On 2024/7/17 22:55, Matthew Wilcox wrote:
> On Wed, Jul 17, 2024 at 08:27:19AM +0000, Zhu Hengbo wrote:
>> +	TP_STRUCT__entry(
>> +		__field(unsigned long, address)
>> +		__field(unsigned long, epc)
>> +		__field(unsigned long, cause)
>> +	),
>> +
>> +	TP_fast_assign(
>> +		__entry->address	= regs->badaddr;
>> +		__entry->epc		= regs->epc;
>> +		__entry->cause		= regs->cause;
>> +	),
>> +
>> +	TP_printk("user page fault, address=%ps epc=%ps cause=0x%lx",
>> +			(void *)__entry->address, (void *)__entry->epc,
>> +			__entry->cause)
> What is "epc"?  You've made this gratuitously different from x86.
> Never do that.  Always copy what somebody else has done unless you have
> a good reason to be different.
Yes, I have referred to the implementation in x86, but the fields in “struct pt_regs” are quite different between RISC-V and x86