On 14.12.2015 09:24, Thierry Reding wrote: > On Mon, Dec 14, 2015 at 09:19:30AM +0100, Geert Uytterhoeven wrote: >> Hi Paul, >> >> On Sun, Dec 13, 2015 at 2:41 AM, Paul Gortmaker >> <paul.gortmaker@xxxxxxxxxxxxx> wrote: >>> This series of commits is a slice of a larger project to ensure >>> people don't have dead code for module removal in non-modular >>> drivers. Overall there was roughly 5k lines of dead code in the >>> kernel due to this. So far we've fixed several areas, like tty, >>> x86, net, etc. and we continue to work on other areas. >>> >>> There are several reasons to not use module_init for code that can >>> never be built as a module, but the big ones are: >>> >>> (1) it is easy to accidentally code up unused module_exit and remove code >>> (2) it can be misleading when reading the source, thinking it can be >>> modular when the Makefile and/or Kconfig prohibit it >>> (3) it requires the include of the module.h header file which in turn >>> includes nearly everything else. >>> >>> Here we convert some module_init() calls into device_initcall() and delete >>> any module_exit and remove code that gets orphaned in the process, for >>> an overall net code reduction, which is always welcome. >>> >>> The use of device_initcall ensures that the init function ordering >>> remains unchanged, but one could argue that PCI host code might be more >>> appropriate to be handled under subsys_initcall. Fortunately we can >>> revisit making this extra change at a later date if desired; it does >>> not need to happen now, and we reduce the risk of introducing >>> regressions at this point in time by separating the two changes. >>> >>> Over half of the drivers changed here already explicitly disallowed any >>> unbind operations. For the rest we make them the same, since there is >>> not really any sensible use case to unbind any built-in bus support that >>> I can think of. >> >> Personally, I think all of these should become tristate, so distro kernels >> don't have to build in PCI(e) support for all SoCs. multi_v7_defconfig kernels >> are becoming too big. >> >> That does not preclude making these modules un-unloadable, though. > > Most of these can't be made tristate as-is, because they use symbols > that aren't exported. Many of those symbols can easily be exported, so > its just a matter of getting the respective patches merged. I disagree > with making the modules non-unloadable, though. I have a local branch > with changes necessary to unload the host controller driver and it > works just fine. Great. Send them out. Thanks, Michal -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
