Messages in this thread |  | | Date | Mon, 9 Oct 2000 15:39:22 -0700 | From | "David S. Miller" <> | Subject | Re: Calling current() from interrupt context |
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Date: Tue, 10 Oct 2000 00:44:58 +0200 From: "Andi Kleen" <ak@suse.de>
On Mon, Oct 09, 2000 at 11:41:13PM +0100, Alan Cox wrote: > I dont actually know a CPU that doesnt have one in SMP mode. Its just often > behind an I/O interface that is slower than ideal
Where would you put it for IA32 ? I don't know any free MSR that could be abused for that, and acessing MSRs is insanely slow anyways. Any other ideas ?
The local APIC holds the hardware cpu number (which happens to equal the logical cpu number in the current x86 code). And I believe the local APIC has a 32-bit scratch register or 2 as well... but don't quote me on that one.
Later, David S. Miller davem@redhat.com - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/
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