[Lucid][SRU] fsl-imx51: Turn on CONFIG_FUNCTION_TRACER option will encounter a linking error

[Bryan Wu]

On 05/04/2010 12:02 PM, AceLan Kao wrote:
> Dear Bryan,
>
> Done.
>

Thanks, For this patch, I'm OK now.

Acked-by: Bryan Wu <bryan.wu at canonical.com>

> And it seems that fsl-imx51 branch doesn't have too much features of
> the ftrace, such as FUNCTION_GRAPH_TRACER, DYNAMIC_FTRACE, MMIOTRACE,
> ... ...
>
> So, we might need to enable the following options for the basic ftrace functions
> CONFIG_FUNCTION_TRACER=y

Yeah, this one is necessary. Could you please help me to provide a config patch 
to turn on this?

> CONFIG_FUNCTION_PROFILER=y

this one is not enabled in our x86 master branch config.

> CONFIG_FTRACE_SELFTEST=y
> CONFIG_FTRACE_STARTUP_TEST=y
>

These 2 testing configs are not enabled in master either, so it might not be 
turned on as default in fsl-imx51.

Maybe we need to go through those FTRACE configs in our UDS-M.

Thanks a lot,
-Bryan


> The following changes since commit 6cd3b3af35f35d128d26eb1ff0064f209a452cf7:
>    Uwe Kleine-König (1):
>          [ARM] support tracing when using newer compilers
>
> are available in the git repository at:
>
>    git://kernel.ubuntu.com/acelan/ubuntu-lucid lp574158
>
> Uwe Kleine-König (1):
>        [ARM] support tracing when using newer compilers
>
>   arch/arm/include/asm/ftrace.h  |    1 +
>   arch/arm/kernel/armksyms.c     |    1 +
>   arch/arm/kernel/entry-common.S |   19 +++++++++++++++++++
>   3 files changed, 21 insertions(+), 0 deletions(-)
>
> 2010/5/4 Bryan Wu<bryan.wu at canonical.com>:
>>
>>
>> On 05/03/2010 03:47 PM, AceLan Kao wrote:
>>>
>>> BugLink:
>>> https://bugs.launchpad.net/ubuntu/+source/linux-fsl-imx51/+bug/574158
>>>
>>> __gnu_mcount_nc() function is implemented in the commit
>>> a8a48cd5add67494d96c13718cab36c465863d07 in the Lucid kernel tree,
>>> we have to cherry pick this commit to make sure the ftrace could be
>>> compiled and works in the fsl-mx51 branch
>>>
>>> I cherry pick this commit and test it on my H/W, the ftrace works,
>>> please consider to git pull this following patches from:
>>>         git://kernel.ubuntu.com/acelan/ubuntu-lucid lp574158
>>>
>>> Thanks,
>>>
>>
>> Great, this patch will let us to play with ftrace in fsl-imx51.
>> And just one comment, could you please add the BugLink info and cherry-pick
>> comments into this commit? just like this,
>> http://kernel.ubuntu.com/git?p=ubuntu/ubuntu-lucid.git;a=commit;h=29c60ccc1a408371885d79d8f8c081fbcb9b10be
>>
>> And one more question, need we enable the CONFIG_FTRACE_* in fsl-imx51
>> config?
>>
>> --
>> Bryan Wu<bryan.wu at canonical.com>
>> Kernel Developer    +86.138-1617-6545 Mobile
>> Ubuntu Kernel Team | Hardware Enablement Team
>> Canonical Ltd.      www.canonical.com
>> Ubuntu - Linux for human beings | www.ubuntu.com
>>
>