Re: [PATCH 17/25] Share ccid3_tx_state_name function via tfrc_ccids

[Gerrit Renker <gerrit@erg.abdn.ac.uk>]

| [CCID-3/4] Share ccid3_tx_state_name function via tfrc_ccids

There is a build problem in declaring the following routines as shared:

#if defined(CONFIG_IP_DCCP_CCID3_DEBUG) || defined(CONFIG_IP_DCCP_CCID4_DEBUG)
static const char *tfrc_tx_state_name(enum tfrc_hc_tx_states state)
{
	/* ... */
}
#endif

#if defined(CONFIG_IP_DCCP_CCID3_DEBUG) || defined(CONFIG_IP_DCCP_CCID4_DEBUG)
static const char *tfrc_rx_state_name(enum tfrc_hc_rx_states state)
{
	/* ... */
#endif

When enabling CCID3_DEBUG, but not CCID4_DEBUG, the following build warnings result:

/usr/src/davem-2.6/net/dccp/ccids/lib/tfrc_ccids.h:163: warning: 'tfrc_tx_state_name' defined but not used
/usr/src/davem-2.6/net/dccp/ccids/lib/tfrc_ccids.h:180: warning: 'tfrc_rx_state_name' defined but not used

The reason is that the header file is #included in ccid4.c and this function is only called from
within ccid4_pr_debug(). But when CCID4_DEBUG is disabled, this macro expands to an emptry string,
so the compiler thinks that tfrc_{rx,tx}_state_name() is not used -- which is actually the case.

So not very happy with the above solution. When getting serious about abstracting and sharing
common code, the best think is probably to use a single debugging function, tfrc_pr_debug.
This would be enabled when at least one of CCID3_DEBUG or CCID4_DEBUG is enabled, and one could
add some magic that the module parameters influence the boolean variable tfrc_debug.

The same could be done for the RTO timer - since the identical menu appears in both places.

Maybe it is better for the moment to `un-share' the code.