On Mon, Apr 9, 2018 at 2:46 AM, Oliver O'Halloran <oohall@xxxxxxxxx> wrote: > Some OF platforms (pseries and some SPARC systems) has their own > implementations of NUMA affinity detection rather than using the generic > OF_NUMA driver, which mainly exists for arm64. For other platforms one > of two fallbacks provided by the base OF driver are used depending on > CONFIG_NUMA. > > In the CONFIG_NUMA=n case the fallback is an inline function in of.h. > In the =y case the fallback is a real function which is defined as a > weak symbol so that it may be overwritten by the architecture if desired. > > The problem with this arrangement is that the real implementations all > export of_node_to_nid(). Unfortunately it's not possible to export the > fallback since it would clash with the non-weak version. As a result > we get build failures when: > > a) CONFIG_NUMA=y && CONFIG_OF=y, and > b) The platform doesn't implement of_node_to_nid(), and > c) A module uses of_node_to_nid() > > Given b) will be true for most platforms this is fairly easy to hit > and has been observed on ia64 and x86. How specifically do we hit this? The only module I see using of_node_to_nid in mainline is Cell EDAC driver. > This patch remedies the problem by introducing the ARCH_HAS_OWN_OF_NUMA > Kconfig option which is selected if an architecture provides an > implementation of of_node_to_nid(). If a platform does not use it's own, > or the generic OF_NUMA, then always use the inline fallback in of.h so > we don't need to futz around with exports. I'm more inclined to figure out how to remove the export and provide a non DT specific function if drivers need to know this. Rob -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
