70ae77f497
Use safe_apic_wait_icr_idle to check ICR idle bit if the vector is NMI_VECTOR to avoid potential hangups in the event of crash when kdump tries to stop the other CPUs. Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp> Signed-off-by: Andi Kleen <ak@suse.de>
129 lines
2.7 KiB
C
129 lines
2.7 KiB
C
#ifndef __ASM_IPI_H
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#define __ASM_IPI_H
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/*
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* Copyright 2004 James Cleverdon, IBM.
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* Subject to the GNU Public License, v.2
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*
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* Generic APIC InterProcessor Interrupt code.
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*
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* Moved to include file by James Cleverdon from
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* arch/x86-64/kernel/smp.c
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*
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* Copyrights from kernel/smp.c:
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*
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* (c) 1995 Alan Cox, Building #3 <alan@redhat.com>
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* (c) 1998-99, 2000 Ingo Molnar <mingo@redhat.com>
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* (c) 2002,2003 Andi Kleen, SuSE Labs.
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* Subject to the GNU Public License, v.2
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*/
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#include <asm/hw_irq.h>
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#include <asm/apic.h>
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/*
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* the following functions deal with sending IPIs between CPUs.
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*
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* We use 'broadcast', CPU->CPU IPIs and self-IPIs too.
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*/
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static inline unsigned int __prepare_ICR (unsigned int shortcut, int vector, unsigned int dest)
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{
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unsigned int icr = shortcut | dest;
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switch (vector) {
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default:
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icr |= APIC_DM_FIXED | vector;
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break;
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case NMI_VECTOR:
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icr |= APIC_DM_NMI;
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break;
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}
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return icr;
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}
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static inline int __prepare_ICR2 (unsigned int mask)
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{
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return SET_APIC_DEST_FIELD(mask);
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}
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static inline void __send_IPI_shortcut(unsigned int shortcut, int vector, unsigned int dest)
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{
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/*
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* Subtle. In the case of the 'never do double writes' workaround
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* we have to lock out interrupts to be safe. As we don't care
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* of the value read we use an atomic rmw access to avoid costly
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* cli/sti. Otherwise we use an even cheaper single atomic write
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* to the APIC.
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*/
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unsigned int cfg;
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/*
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* Wait for idle.
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*/
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apic_wait_icr_idle();
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/*
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* No need to touch the target chip field
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*/
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cfg = __prepare_ICR(shortcut, vector, dest);
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/*
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* Send the IPI. The write to APIC_ICR fires this off.
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*/
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apic_write(APIC_ICR, cfg);
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}
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/*
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* This is used to send an IPI with no shorthand notation (the destination is
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* specified in bits 56 to 63 of the ICR).
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*/
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static inline void __send_IPI_dest_field(unsigned int mask, int vector, unsigned int dest)
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{
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unsigned long cfg;
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/*
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* Wait for idle.
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*/
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if (unlikely(vector == NMI_VECTOR))
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safe_apic_wait_icr_idle();
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else
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apic_wait_icr_idle();
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/*
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* prepare target chip field
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*/
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cfg = __prepare_ICR2(mask);
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apic_write(APIC_ICR2, cfg);
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/*
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* program the ICR
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*/
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cfg = __prepare_ICR(0, vector, dest);
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/*
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* Send the IPI. The write to APIC_ICR fires this off.
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*/
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apic_write(APIC_ICR, cfg);
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}
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static inline void send_IPI_mask_sequence(cpumask_t mask, int vector)
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{
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unsigned long flags;
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unsigned long query_cpu;
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/*
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* Hack. The clustered APIC addressing mode doesn't allow us to send
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* to an arbitrary mask, so I do a unicast to each CPU instead.
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* - mbligh
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*/
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local_irq_save(flags);
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for_each_cpu_mask(query_cpu, mask) {
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__send_IPI_dest_field(x86_cpu_to_apicid[query_cpu],
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vector, APIC_DEST_PHYSICAL);
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}
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local_irq_restore(flags);
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}
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#endif /* __ASM_IPI_H */
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