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Commit 569712b2 authored by Yinghai Lu's avatar Yinghai Lu Committed by Ingo Molnar
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x86: fix wakeup_cpu with numaq/es7000, v2



Impact: fix secondary-CPU wakeup/init path with numaq and es7000

While looking at wakeup_secondary_cpu for WAKE_SECONDARY_VIA_NMI:

|#ifdef WAKE_SECONDARY_VIA_NMI
|/*
| * Poke the other CPU in the eye via NMI to wake it up. Remember that the normal
| * INIT, INIT, STARTUP sequence will reset the chip hard for us, and this
| * won't ... remember to clear down the APIC, etc later.
| */
|static int __devinit
|wakeup_secondary_cpu(int logical_apicid, unsigned long start_eip)
|{
|        unsigned long send_status, accept_status = 0;
|        int maxlvt;
|...
|        if (APIC_INTEGRATED(apic_version[phys_apicid])) {
|                maxlvt = lapic_get_maxlvt();

I noticed that there is no warning about undefined phys_apicid...

because WAKE_SECONDARY_VIA_NMI and WAKE_SECONDARY_VIA_INIT can not be
defined at the same time. So NUMAQ is using wrong wakeup_secondary_cpu.

WAKE_SECONDARY_VIA_NMI, WAKE_SECONDARY_VIA_INIT and
WAKE_SECONDARY_VIA_MIP are variants of a weird and fragile
preprocessor-driven "HAL" mechanisms to specify the kind of secondary-CPU
wakeup strategy a given x86 kernel will use.

The vast majority of systems want to use INIT for secondary wakeup - NUMAQ
uses an NMI, (old-style-) ES7000 uses 'MIP' (a firmware driven in-memory
flag to let secondaries continue).

So convert these mechanisms to x86_quirks and add a
->wakeup_secondary_cpu() method to specify the rare exception
to the sane default.

Extend genapic accordingly as well, for 32-bit.

While looking further, I noticed that functions in wakecup.h for numaq
and es7000 are different to the default in mach_wakecpu.h - but smpboot.c
will only use default mach_wakecpu.h with smphook.h.

So we need to add mach_wakecpu.h for mach_generic, to properly support
numaq and es7000, and vectorize the following SMP init methods:

	int trampoline_phys_low;
	int trampoline_phys_high;
	void (*wait_for_init_deassert)(atomic_t *deassert);
	void (*smp_callin_clear_local_apic)(void);
	void (*store_NMI_vector)(unsigned short *high, unsigned short *low);
	void (*restore_NMI_vector)(unsigned short *high, unsigned short *low);
	void (*inquire_remote_apic)(int apicid);

Signed-off-by: default avatarYinghai Lu <yinghai@kernel.org>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent e14c8bf8
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