Re: [PATCH 11/21] trace: Use -mcount-record for dynamic ftrace

Steven Rostedt
2017-12-01T00:22:36Z

On Mon, 27 Nov 2017 13:34:13 -0800
Andi Kleen <andi@firstfloor.org> wrote:

> From: Andi Kleen <ak@linux.intel.com>
>
> gcc 5 supports a new -mcount-record option to generate ftrace
> tables directly. This avoids the need to run record_mcount
> manually.
>
> Use this option when available.
>
> So far doesn't use -mcount-nop, which also exists now.
>
> This is needed to make ftrace work with LTO because the
> normal record-mcount script doesn't run over the link
> time output.
>
> It should also improve build times slightly in the general
> case.
>
> Cc: rostedt@goodmis.org
> Signed-off-by: Andi Kleen <ak@linux.intel.com>
> ---

Hi Andi,

Thanks for sending this. I'm currently trying to catch up on all the
changes that need to get into 4.15 and will be doing a bit of
traveling.

I plan on looking at this in a week or two, and add it to the 4.16
queue.

-- Steve