Hi Gerry, Does it seem reasonable to enforce the requirement that all CPUs in a domain need to be power manageable in order to manage any of the CPUs in that domain? I don't know much about what you are planning to do with hotplug. Is it possible that one CPU in a domain will detach and others in the domain will be left attached?
Thanks, Mark Liu, Jiang wrote: > Hi Mark and Anup, > Currently I'm working on a project relative to CPU hotplug on x86 > system. The new design is much more friendly to CPU hotplug than currently on > in onnv tree, really appreciate your work. I still have several questions > relative to CPU hotplug. > 1) Could you please help to turn on support for driver detach in > cpudrv.c? CPU hotplug has dependency on that. > 2) Seems cpupm subsystem still needs configuration item > 'domain_cpu-devices="/cpus/c...@*"' in ppm.conf to catch all cpus at boot > time. We are discussing some sort of device tree reorganization for x86 > system, which may break current CPU domain support code in ppm driver. The > sample device tree as below, > /devices/sysbus/processor at 0/cpu at 0 > /devices/sysbus/processor at 0/cpu at 1 > /devices/sysbus/processor at 1/cpu at 2 > /devices/sysbus/processor at 1/cpu at 3 > I think it's not ease to fit above device tree into current ppm driver > on x86 system, any suggestion here? > 3) Should line 876 and 896 in cpu_idle.c be removed? Seems it's not > used any more. > 4) Should we add reference count support in CPU domain data structure? > For current implementation, all P/T/C domains will be freed if cpupm_free is > called once for any cpu, which will make all cma_domain fields in > cpupm_mach_state_t invalid. It may cause access violation, I think. It will > also be needed to support CPU hotplug. > 5) Seems current CPU domain relative code doesn't support CPU hot > adding/removing, is that true? > Thanks! > > >> -----Original Message----- >> From: tesla-dev-bounces at opensolaris.org >> [mailto:tesla-dev-bounces at opensolaris.org] On Behalf Of Mark Haywood >> Sent: 2008?12?9? 10:14 >> To: tesla-dev at opensolaris.org >> Subject: [tesla-dev] CPUPM support in the kernel >> >> Anup and I have been working on moving the core CPUPM support from the >> CPU driver - into the kernel. Our goal is to make the CPU driver >> specific to polling CPU power management and not have PAD >> depend on the >> driver at all. That means moving a fair bit of the i86pc specific CPU >> power management support (ACPI parsing and caching, speedstep, pwrnow, >> cstate and tstate handling) into the kernel. This eliminates the need >> for callback mechanism into the CPU driver. Unfortunately, >> since acpica >> is a module, it does require callbacks for that. But those have been >> centralized into the existing uts/i86pc/os/acpi_stubs.c file. >> >> We've posted a webrev of our effort at: >> >> http://cr.opensolaris.org/~mhaywood/cpupm-move/ >> >> We'd appreciate any comments. >> >> Thanks! >> Mark >> >> _______________________________________________ >> tesla-dev mailing list >> tesla-dev at opensolaris.org >> http://mail.opensolaris.org/mailman/listinfo/tesla-dev >> >>
