On 01/03/2013 05:21 AM, Russell King - ARM Linux wrote: > On Thu, Jan 03, 2013 at 12:02:59PM +0000, Will Deacon wrote: >> You need the smp_send_stop call in order to send the cpu_kill (looks like >> tegra needs die and then kill). So you really need hotplug support as well >> as suspend for this to do much (if not, the secondaries end up spinning >> with interrupts disabled which is probably the best we can do anyway). >> >> We could add SUSPEND as a KEXEC dependency if SMP (we already have HOTPLUG >> there) if you like? > > Or we could look into bringing in the code to do this when KEXEC is > enabled - which would mean an amount of restructuring of the Kconfig > files. I'm not sure if any of this thread means we should hold off on this patch, or just that the Kconfig could/should be enhanced later? One thing I did just notice with my patch: disable_nonboot_cpus() ends up being called twice for the poweroff path: [ 30.461847] Disabling non-boot CPUs ... [ 30.478797] CPU1: shutdown [ 30.492104] Power down. [ 30.494578] Disabling non-boot CPUs ... Is this worth worrying about? It's because kernel_power_off() calls disable_nonboot_cpus() then machine_shutdown() which also calls disable_nonboot_cpus().
