debugfs mount point [LWN.net]

debugfs mount point

Posted Mar 16, 2009 19:33 UTC (Mon) by nevets (subscriber, #11875)
In reply to: debugfs mount point by gregkh
Parent article: A look at ftrace

Although I do mention /sys/kernel/debug in ftrace.txt, I find that too much to type. But perhaps I should change my general instructions to be...

mount -t debugfs none /sys/kernel/debug/
ln -s /sys/kernel/debug /debug

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debugfs mount point

Posted Mar 17, 2009 15:42 UTC (Tue) by vapier (subscriber, #15768) [Link]

i think you misread ... he said "type", not "hype"

debugfs mount point

Posted Mar 17, 2009 16:04 UTC (Tue) by nevets (subscriber, #11875) [Link]

Thanks, I was confused by what he meant by "Hype".

But to his question about spurious directories in root. I still have on many systems an empty /opt. How's that different? I think seeing a /debug directory is quite obvious to what it is. Are you that worried about an inode that is seldom used?

The only ones that ever complain about /debug are a few kernel developers that know that /sys/kernel/debug was made for that purpose. The majority of people that use ftrace seem to mount the debugfs on /debug.

Typing "cat /debug/tracing/trace" is much faster than typing
"cat /sys/kernel/debug/tracing/trace".

debugfs mount point

Posted Mar 19, 2009 3:01 UTC (Thu) by daniel (subscriber, #3181) [Link]

I prefer /debug over /sys/kernel/debug/. After all, this symbol only needs to be there for debugging, if present then it is unmistakable why it is there, and there is no real chance of collision.