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Debugfs

Posted Dec 16, 2004 12:42 UTC (Thu) by ekj (guest, #1524)
Parent article: Debugfs

One thing I never 100% got the point of is the change from procfs to
sysfs.

I mean, other than the fact that normally "procfs" is mounted at /proc and
"sysfs" is mounted at /sys, what is the fundamental difference ?

Yes I'm aware that different information is available, in different
formats, in the two hierarchies. What I do *not* understand is what
fundamental reason prevented the files now populating sysfs from instead
being created in proc.

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Sysfs vs Procfs

Posted Dec 16, 2004 13:15 UTC (Thu) by alex (subscriber, #1355) [Link]

IIRC it was because /proc was meant to be to store process information but then turned into a maze of twisty directories with all sorts of random data dumped into it - including device information.

Sysfs on the other hand is designed to be a representation of the kernel device model. For that reason stuff isn't just dumped in, the position of nodes with sysfs actually represents the hierachy of devices in relation to their subsytems.

Sysfs vs Procfs

Posted Dec 17, 2004 10:21 UTC (Fri) by xav (guest, #18536) [Link]

Yes, the big difference is that sysfs can be parsed automatically, whereas procfs needs ad-hoc tools for each of its components.

Why multiple filesystems?

Posted Dec 17, 2004 22:18 UTC (Fri) by giraffedata (subscriber, #1954) [Link]

What is even less clear to me than why procfs isn't good enough for what sysfs does is why procfs isn't good enough for what debugfs does.

The /proc name space did get messed up when people decided to put stuff other than process information (pid entries) in it. It would make more sense to call it something else and have a 'proc' directory in it for the pid entries. But other than that, I can't see why someone would object to having a debug interface in /proc but not object to it being in /debug.

As a kernel developer, I don't see anything that would make me want to learn a whole extra interface rather than put my debug interface in /proc.