On Mon, May 6, 2019 at 10:57 AM Dave Hansen <dave.han...@intel.com> wrote: > > > -static inline void remove_memory(int nid, u64 start, u64 size) {} > > +static inline bool remove_memory(int nid, u64 start, u64 size) > > +{ > > + return -EBUSY; > > +} > > This seems like an appropriate place for a WARN_ONCE(), if someone > manages to call remove_memory() with hotplug disabled. > > BTW, I looked and can't think of a better errno, but -EBUSY probably > isn't the best error code, right? > > > -void remove_memory(int nid, u64 start, u64 size) > > +/** > > + * remove_memory > > + * @nid: the node ID > > + * @start: physical address of the region to remove > > + * @size: size of the region to remove > > + * > > + * NOTE: The caller must call lock_device_hotplug() to serialize hotplug > > + * and online/offline operations before this call, as required by > > + * try_offline_node(). > > + */ > > +void __remove_memory(int nid, u64 start, u64 size) > > { > > + > > + /* > > + * trigger BUG() is some memory is not offlined prior to calling this > > + * function > > + */ > > + if (try_remove_memory(nid, start, size)) > > + BUG(); > > +} > > Could we call this remove_offline_memory()? That way, it makes _some_ > sense why we would BUG() if the memory isn't offline.
Please WARN() instead of BUG() because failing to remove memory should not be system fatal.