Re: [PATCH -v5 09/11] tracing: add IRQENTRY_EXIT for MIPS

Frederic Weisbecker
2009-10-26T00:36:25Z

2009/10/25 Wu Zhangjin <wuzhangjin@gmail.com>:
> This patch fix the following error with FUNCTION_GRAPH_TRACER=y:
>
> kernel/built-in.o: In function `print_graph_irq':
> trace_functions_graph.c:(.text+0x6dba0): undefined reference to `__irqentry_text_start'
> trace_functions_graph.c:(.text+0x6dba8): undefined reference to `__irqentry_text_start'
> trace_functions_graph.c:(.text+0x6dbd0): undefined reference to `__irqentry_text_end'
> trace_functions_graph.c:(.text+0x6dbd4): undefined reference to `__irqentry_text_end'
>
> (This patch is need to support function graph tracer of MIPS)

If you want to enjoy this section, you'd need to tag the
mips irq entry functions with "__irq_entry" :)

I guess there is a do_IRQ() in mips that is waiting for that (and
probably some others).
The effect is that interrupt areas are cut with a pair of arrows
in the trace, so that you more easily spot interrupts in the traces

May be I missed this part in another patch in this series though...