Re: [PATCH 58/76] idle, x86: Allow off-lined CPU to enter deeper C states

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 04/02/12 13:25, Tony Luck wrote:
+       while (1) {
+
+               if (cx->entry_method == ACPI_CSTATE_HALT)
+                       halt();

What's the intent here?  I think that I can just set up a function pointer
named "halt" on ia64 and point it to my cpu_halt() function (which looks
for the deepest C-state, and then calls PAL to enter it. Is that equivalent
to what the x86 "halt()" function does?


x86 halt() causes processor to go to C1 state (which is often not the deepest). But other than that it seems similar to what you are describing.

However, the fix that you are proposing will only help ia64 and I wonder whether others architectures may have the same problem?

(And I don't think inb/inl should cause you any trouble since they are already used, for example, in acpi_idle_do_entry())

-boris


_______________________________________________
linux-pm mailing list
linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx
https://lists.linuxfoundation.org/mailman/listinfo/linux-pm


[Index of Archives]     [Linux ACPI]     [Netdev]     [Ethernet Bridging]     [Linux Wireless]     [CPU Freq]     [Kernel Newbies]     [Fedora Kernel]     [Security]     [Linux for Hams]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux RAID]     [Linux Admin]     [Samba]

  Powered by Linux