60063497a9
This allows us to move duplicated code in <asm/atomic.h> (atomic_inc_not_zero() for now) to <linux/atomic.h> Signed-off-by: Arun Sharma <asharma@fb.com> Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
65 lines
1.6 KiB
C
65 lines
1.6 KiB
C
/*
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* Kernel-based Virtual Machine driver for Linux
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*
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* This module enables machines with Intel VT-x extensions to run virtual
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* machines without emulation or binary translation.
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*
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* timer support
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*
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* Copyright 2010 Red Hat, Inc. and/or its affiliates.
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*
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* This work is licensed under the terms of the GNU GPL, version 2. See
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* the COPYING file in the top-level directory.
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*/
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#include <linux/kvm_host.h>
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#include <linux/kvm.h>
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#include <linux/hrtimer.h>
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#include <linux/atomic.h>
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#include "kvm_timer.h"
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static int __kvm_timer_fn(struct kvm_vcpu *vcpu, struct kvm_timer *ktimer)
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{
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int restart_timer = 0;
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wait_queue_head_t *q = &vcpu->wq;
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/*
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* There is a race window between reading and incrementing, but we do
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* not care about potentially losing timer events in the !reinject
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* case anyway. Note: KVM_REQ_PENDING_TIMER is implicitly checked
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* in vcpu_enter_guest.
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*/
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if (ktimer->reinject || !atomic_read(&ktimer->pending)) {
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atomic_inc(&ktimer->pending);
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/* FIXME: this code should not know anything about vcpus */
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kvm_make_request(KVM_REQ_PENDING_TIMER, vcpu);
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}
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if (waitqueue_active(q))
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wake_up_interruptible(q);
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if (ktimer->t_ops->is_periodic(ktimer)) {
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hrtimer_add_expires_ns(&ktimer->timer, ktimer->period);
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restart_timer = 1;
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}
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return restart_timer;
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}
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enum hrtimer_restart kvm_timer_fn(struct hrtimer *data)
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{
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int restart_timer;
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struct kvm_vcpu *vcpu;
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struct kvm_timer *ktimer = container_of(data, struct kvm_timer, timer);
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vcpu = ktimer->vcpu;
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if (!vcpu)
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return HRTIMER_NORESTART;
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restart_timer = __kvm_timer_fn(vcpu, ktimer);
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if (restart_timer)
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return HRTIMER_RESTART;
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else
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return HRTIMER_NORESTART;
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}
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