Hi Nicholas, This patchset uses krefs to refcount structures shared across threads. LIO is full of these because configfs-based configuration actions can be removing an object, even while that object is being used by a SCSI command. Using kref to free the struct on whichever thread drops the last reference allows us to avoid busy-waiting in configfs removal functions. Next, this set removes the statically-sized tpg lun and deve arrays in favor of dynamically adding entries into rbtrees. This reduces memory consumption and allows more than 255 luns per tpg and initiator mapping. Except for some rbtree lookups, these changes are entirely in the configuration paths of Lio. I have tested these as extensively as I can, and it's ready for wider testing. Note: patch 22 converts a percpu refcount to a normal kref. I'd argue the benefit is really in the "refcount" part rather than the "percpu", so a simpler kref does the job, but we might want to discuss this some more. Please review. Thanks -- Regards -- Andy p.s. https://github.com/agrover/linux.git for_nab -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
