ehci dynamic debug problem

From: Johannes Stezenbach
Date: Fri Apr 13 2012 - 04:56:17 EST


Hi,

I have a quirky device and enabled dynamic debug to
see the ehci driver debug messages to help me diagnose
the problem. I see stuff like this:

[1790542.363321] ehci_hub_control:940: ehci_hcd 0000:00:1a.0: \xffffffd8\xffffff94\xffffff94\xffffffa8\xffffff81\xffffffff\xffffffff\xffffffff\xffffffff}[<\xffffff81\xffffffff\xffffffff\xffffffff\xffffffff\x01
[1790542.363470] ehci_hub_control:940: ehci_hcd 0000:00:1a.0: \xffffffd8\xffffff94\xffffff94\xffffffa8\xffffff81\xffffffff\xffffffff\xffffffff\xffffffff}[<\xffffff81\xffffffff\xffffffff\xffffffff\xffffffff\x01

The problem is in ehci-dbg.c:

#define dbg_port(ehci, label, port, status) { \
char _buf [80]; \
dbg_port_buf (_buf, sizeof _buf, label, port, status); \
ehci_dbg (ehci, "%s\n", _buf); \
}

dbg_port_buf() is a no op when DEBUG is not defined, thus
the ehci_dbg() prints uninitialized memory.


Does dynamic debug offer an "is the message two lines below enabled" test?
Simply changing the "#ifdef DEBUG" for dbg_port_buf()
to "#if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG)"
is probably not acceptable due to the overhead of dbg_port_buf()?


Thanks,
Johannes
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