Re: [PATCH] leds: remove PAGE_SIZE limit of /sys/class/leds/<led>/trigger

From: Pavel Machek
Date: Sun Sep 01 2019 - 13:23:28 EST


Hi!

> Reading /sys/class/leds/<led>/trigger returns all available LED triggers.
> However, the size of this file is limited to PAGE_SIZE because of the
> limitation for sysfs attribute.
>
> Enabling LED CPU trigger on systems with thousands of CPUs easily hits
> PAGE_SIZE limit, and makes it impossible to see all available LED triggers
> and which trigger is currently activated.
>
> This converts /sys/class/leds/<led>/trigger to bin attribute and removes
> the PAGE_SIZE limitation.
>
> Cc: Jacek Anaszewski <jacek.anaszewski@xxxxxxxxx>

Nothing obviously wrong from a quick look...

Acked-by: Pavel Machek <pavel@xxxxxx>

Thanks a lot for doing this!

I believe we should cc Greg here.

BTW if you care about cpuled trigger... it would be cool to turn it into one trigger and pass
a cpu number as a parameter. It is good to see this limit fixed, but real solution is to
register one trigger per driver.

Best regards,
Pavel

--
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