Dear all, I'm working on refactoring the SMP boot and CPU hotplug implementation. The current code has evolved over time into a conglomerate of warts. My main goals are to: - reduce the architecture code by moving repeating constructs to the core - redesigning the handling of per cpu threads. There is no point to tear down the threads just to create them again. - restructuring the notifier facility into a proper tree with dependencies to avoid the gazillion of callbacks and moving setup/teardown code into the context of the upcoming/dying cpu The motivation behind this work is the cpu hotplug nightmare which we are facing in the RT kernel and the requests from several groups (e.g. ARM) to make hotplug more lightweight and faster. This first part moves the idle thread management for non-boot cpus into the core. fork_idle() is called in a workqueue as it is implemented in a few architectures already. This is necessary when not all cpus are brought up by the early boot code as otherwise we would take a ref on the user task VM of the thread which brings the cpu up via the sysfs interface. This converts all architectures except m32r, mn10300, tile and UM to the new core facility. These architecture are calling fork_idle() in the very early boot code in smp_prepare_cpus() for unknown reasons. I haven't analyzed yet, whether this is on purpose or can be moved over to the generic facility. It'd be nice if the responsible maintainers could look into that as well. Thanks, tglx -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
