Re: Unused trace event in erofs

From: Gao Xiang
Date: Fri Jun 13 2025 - 02:08:51 EST


Hi Steven,

On 2025/6/13 10:49, Steven Rostedt wrote:
I have code that will trigger a warning if a trace event is defined but
not used[1]. It gives a list of unused events. Here's what I have for
erofs:

warning: tracepoint 'erofs_destroy_inode' is unused.

I'm fine to remove it, also I wonder if it's possible to disable
erofs tracepoints (rather than disable all tracepoints) in some
embedded use cases because erofs tracepoints might not be useful for
them and it can save memory (and .ko size) as you said below.


Each trace event can take up to around 5K in memory regardless if they
are used or not. Soon there will be warnings when they are defined but
not used. Please remove any unused trace event or at least hide it
under an #ifdef if they are used within configs. I'm planning on adding
these warning in the next merge window.

If you don't have some interest to submit a removal patch, I will post
a patch later.

Thanks,
Gao Xiang


Thanks,

-- Steve

[1] https://lore.kernel.org/linux-trace-kernel/20250612235827.011358765@xxxxxxxxxxx/