Re: [GIT PULL] tracing: Updates for 7.2

[Julia Lawall]

On Fri, 19 Jun 2026, Linus Torvalds wrote:

> On Fri, 19 Jun 2026 at 05:15, Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
> >
> > Many developers use trace_printk() over printk().
>
> You're on some bad drugs, Steven.
>
> By "many developers" you clearly must have meant "almost nobody".

I use trace_printk on a daily basis.  Tracepoints are useful to get an
overview of what is going on, and then trace_printk is useful for
interleaving that with information relevant to the specific problem at
hand.

julia


>
> > Requiring people to
> > add that include for every use case would severely limit debugging of
> > the kernel. Would you be OK if we did the same for printk?
>
> Stop making inane and silly arguments that have nothing to do with reality.
>
> The two are not the same:
>
>   $ git grep -wl printk | wc -l
>   3212
>   $ git grep -wl trace_printk | wc -l
>   50
>
> and making them sound remotely similar is just making you look dishonst.
>
> Look, the attached patch makes my defconfig build cleanly, and makes a
>
>   $ touch include/linux/trace_printk.h
>
> cause my recompile to build just a handful of files. While touching
> linux/kernel.h causes thousands of files to be re-build.
>
> That's a whopping
>
>  6 files changed, 6 insertions(+), 1 deletion(-)
>
> to make my tree build without including <linux/trace_printk.h> everywhere.
>
> Now, that's _just_ my defconfig, and the full build clearly has a
> handful of other cases. From a quick look, mostly in the 'samples'
> directory.
>
> But it looks like a *handful* of other cases.
>
> Now, if the same was true for printk(), I'd happily split that into
> some other header too.
>
> But it isn't.
>
> Because we live in reality.
>
>                Linus
>