Re: [PATCH] Add support for profiling Loongson 2E

[Ralf Baechle <ralf@linux-mips.org>]

On Tue, Jul 24, 2007 at 01:20:27PM +0400, Dajie Tan wrote:

> This patch adds support for profiling Loongson 2E. It's been tested on
> FuLong mini PC(loongson2e inside).

First of all, your patch has been garbled when mailing.


[.. Lots of arch/mips code deleted ...]

No complaints upto this point.  But:

> diff -urN b/drivers/oprofile/cpu_buffer.c a/drivers/oprofile/cpu_buffer.c
> --- b/drivers/oprofile/cpu_buffer.c	2007-07-24 13:00:54.000000000 +0800
> +++ a/drivers/oprofile/cpu_buffer.c	2007-07-19 08:22:15.000000000 +0800
> @@ -148,6 +148,10 @@
>            unsigned long pc, unsigned long event)
> {
> 	struct op_sample * entry = &cpu_buf->buffer[cpu_buf->head_pos];
> +
> +	if(!entry)
> +		return;
> +
> 	entry->eip = pc;
> 	entry->event = event;
> 	increment_head(cpu_buf);

Why do you need this change?  It almost looks as if you're papering over
a bug where add_sample should not be called at all.

  Ralf