Re: [PATCH RFC v3 0/8] kernel-hacking: introduce CONFIG_NO_AUTO_INLINE

[Peter Zijlstra]

On Thu, May 01, 2025 at 02:19:47PM +0000, Brendan Jackman wrote:
> On Tue Apr 29, 2025 at 12:35 PM UTC, Christoph Hellwig wrote:
> > On Tue, Apr 29, 2025 at 12:06:04PM +0800, Chen Linxuan via B4 Relay wrote:
> >> This series introduces a new kernel configuration option NO_AUTO_INLINE,
> >> which can be used to disable the automatic inlining of functions.
> >> 
> >> This will allow the function tracer to trace more functions
> >> because it only traces functions that the compiler has not inlined.
> >
> > This still feels like a bad idea because it is extremely fragile.
> 
> Can you elaborate on that - does it introduce new fragility?

given it needs to sprinkle __always_inline around where it wasn't needed
before, yeah.

Also, why would you want this? function tracer is already too much
output. Why would you want even more?