Re: move DEVICE_POLLING from opt_global.h to opt_polling.h

[Sepherosa Ziehau <sepherosa@xxxxxxxxx>]

On 10/22/05, Matthew Dillon <dillon@xxxxxxxxxxxxxxxxxxxx> wrote:
>
> :Following patch move DEVICE_POLLING from opt_global.h to opt_polling.h:
> :http://leaf.dragonflybsd.org/~sephe/opt_polling.diff
> :
> :Please review it.
> :
> :Best Regards,
> :sephe
> :
> :--
> :Live Free or Die
>
>     net/if_var.h has all sorts of conditionals on DEVICE_POLLING.  Either

net/if_var.h was left out intentionally, since
1) Size and layout of "struct ifnet" are not changed, no matter
whether DEVICE_POLLING is defined or not.  So any *.c files that does
not want DEVICE_POLLING can safely ignore opt_polling.h
2) Any *.c file that wants DEVICE_POLLING supports will include
opt_polling.h at its very beginning(at least before net/if.h or
net/if_var.h).  This will bring in ifnet.if_poll, poll_cmd and various
polling related functions' declaration.  Again, as pointed out in 1),
size and layout of "struct ifnet" are not changed.
3) IMHO, including opt_*.h in system header files will cause trouble

>     net/if_var.h needs to include opt_polling.h (conditionally on _KERNEL
>     or KLD_MODULE), or the option has to be left in opt_global.h.
>
>     I think there were some recent commits that allow modules to use
>     the primary opt_*.h files for a compile so its possible that this
>     won't break the module build, but it would have to be tested.

If module is not built during kernel building, the primary opt_*.h
will not be used.  This is the main reason that I want to put
DEVICE_POLLING in a seperate opt_x.h

Best Regards,
sephe

--
Live Free or Die