korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-12-24 11:34:50 +08:00
Code Issues Packages Projects Releases Wiki Activity
c9a3c58f01
linux/include/kvm/arm_arch_timer.h

82 lines
2.4 KiB
C
Raw Normal View History

ARM: KVM: arch_timers: Add guest timer core support Add some the architected timer related infrastructure, and support timer interrupt injection, which can happen as a resultof three possible events: - The virtual timer interrupt has fired while we were still executing the guest - The timer interrupt hasn't fired, but it expired while we were doing the world switch - A hrtimer we programmed earlier has fired Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2013-01-24 02:21:58 +08:00
/*
* Copyright (C) 2012 ARM Ltd.
* Author: Marc Zyngier <marc.zyngier@arm.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef __ASM_ARM_KVM_ARCH_TIMER_H
#define __ASM_ARM_KVM_ARCH_TIMER_H
#include <linux/clocksource.h>
#include <linux/hrtimer.h>
#include <linux/workqueue.h>
KVM: arm/arm64: Abstract virtual timer context into separate structure Abstract virtual timer context into a separate structure and change all callers referring to timer registers, irq state and so on. No change in functionality. This is about to become very handy when adding the EL1 physical timer. Signed-off-by: Jintack Lim <jintack@cs.columbia.edu> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-03 23:19:59 +08:00
struct arch_timer_context {
ARM: KVM: arch_timers: Add guest timer core support Add some the architected timer related infrastructure, and support timer interrupt injection, which can happen as a resultof three possible events: - The virtual timer interrupt has fired while we were still executing the guest - The timer interrupt hasn't fired, but it expired while we were doing the world switch - A hrtimer we programmed earlier has fired Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2013-01-24 02:21:58 +08:00
/* Registers: control register, timer value */
KVM: arm/arm64: Abstract virtual timer context into separate structure Abstract virtual timer context into a separate structure and change all callers referring to timer registers, irq state and so on. No change in functionality. This is about to become very handy when adding the EL1 physical timer. Signed-off-by: Jintack Lim <jintack@cs.columbia.edu> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-03 23:19:59 +08:00
u32 cnt_ctl;
u64 cnt_cval;
/* Timer IRQ */
struct kvm_irq_level irq;
/* Active IRQ state caching */
bool active_cleared_last;
KVM: arm/arm64: Move cntvoff to each timer context Make cntvoff per each timer context. This is helpful to abstract kvm timer functions to work with timer context without considering timer types (e.g. physical timer or virtual timer). This also would pave the way for ever doing adjustments of the cntvoff on a per-CPU basis if that should ever make sense. Signed-off-by: Jintack Lim <jintack@cs.columbia.edu> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-03 23:20:00 +08:00
/* Virtual offset */
u64 cntvoff;
KVM: arm/arm64: Abstract virtual timer context into separate structure Abstract virtual timer context into a separate structure and change all callers referring to timer registers, irq state and so on. No change in functionality. This is about to become very handy when adding the EL1 physical timer. Signed-off-by: Jintack Lim <jintack@cs.columbia.edu> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-03 23:19:59 +08:00
};
ARM: KVM: arch_timers: Add guest timer core support Add some the architected timer related infrastructure, and support timer interrupt injection, which can happen as a resultof three possible events: - The virtual timer interrupt has fired while we were still executing the guest - The timer interrupt hasn't fired, but it expired while we were doing the world switch - A hrtimer we programmed earlier has fired Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2013-01-24 02:21:58 +08:00
KVM: arm/arm64: Abstract virtual timer context into separate structure Abstract virtual timer context into a separate structure and change all callers referring to timer registers, irq state and so on. No change in functionality. This is about to become very handy when adding the EL1 physical timer. Signed-off-by: Jintack Lim <jintack@cs.columbia.edu> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-03 23:19:59 +08:00
struct arch_timer_cpu {
struct arch_timer_context vtimer;
KVM: arm/arm64: Add the EL1 physical timer context Add the EL1 physical timer context. Signed-off-by: Jintack Lim <jintack@cs.columbia.edu> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-03 23:20:02 +08:00
struct arch_timer_context ptimer;
ARM: KVM: arch_timers: Add guest timer core support Add some the architected timer related infrastructure, and support timer interrupt injection, which can happen as a resultof three possible events: - The virtual timer interrupt has fired while we were still executing the guest - The timer interrupt hasn't fired, but it expired while we were doing the world switch - A hrtimer we programmed earlier has fired Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2013-01-24 02:21:58 +08:00
/* Background timer used when the guest is not running */
struct hrtimer timer;
/* Work queued with the above timer expires */
struct work_struct expired;
/* Background timer active */
bool armed;
KVM: arm/arm64: Move timer IRQ map to latest possible time We are about to modify the VGIC to allocate all data structures dynamically and store mapped IRQ information on a per-IRQ struct, which is indeed allocated dynamically at init time. Therefore, we cannot record the mapped IRQ info from the timer at timer reset time like it's done now, because VCPU reset happens before timer init. A possible later time to do this is on the first run of a per VCPU, it just requires us to move the enable state to be a per-VCPU state and do the lookup of the physical IRQ number when we are about to run the VCPU. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Andre Przywara <andre.przywara@arm.com>
2016-05-18 23:26:00 +08:00
/* Is the timer enabled */
bool enabled;
ARM: KVM: arch_timers: Add guest timer core support Add some the architected timer related infrastructure, and support timer interrupt injection, which can happen as a resultof three possible events: - The virtual timer interrupt has fired while we were still executing the guest - The timer interrupt hasn't fired, but it expired while we were doing the world switch - A hrtimer we programmed earlier has fired Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2013-01-24 02:21:58 +08:00
};
int kvm_timer_hyp_init(void);
KVM: arm/arm64: Move timer IRQ map to latest possible time We are about to modify the VGIC to allocate all data structures dynamically and store mapped IRQ information on a per-IRQ struct, which is indeed allocated dynamically at init time. Therefore, we cannot record the mapped IRQ info from the timer at timer reset time like it's done now, because VCPU reset happens before timer init. A possible later time to do this is on the first run of a per VCPU, it just requires us to move the enable state to be a per-VCPU state and do the lookup of the physical IRQ number when we are about to run the VCPU. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Andre Przywara <andre.przywara@arm.com>
2016-05-18 23:26:00 +08:00
int kvm_timer_enable(struct kvm_vcpu *vcpu);
KVM: arm/arm64: timer: Allow the timer to control the active state In order to remove the crude hack where we sneak the masked bit into the timer's control register, make use of the phys_irq_map API control the active state of the interrupt. This causes some limited changes to allow for potential error propagation. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2014-06-23 20:59:13 +08:00
int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu,
KVM: arm/arm64: Initialize the emulated EL1 physical timer Initialize the emulated EL1 physical timer with the default irq number. Signed-off-by: Jintack Lim <jintack@cs.columbia.edu> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-03 23:20:03 +08:00
const struct kvm_irq_level *virt_irq,
const struct kvm_irq_level *phys_irq);
ARM: KVM: arch_timers: Add guest timer core support Add some the architected timer related infrastructure, and support timer interrupt injection, which can happen as a resultof three possible events: - The virtual timer interrupt has fired while we were still executing the guest - The timer interrupt hasn't fired, but it expired while we were doing the world switch - A hrtimer we programmed earlier has fired Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2013-01-24 02:21:58 +08:00
void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu);
void kvm_timer_flush_hwstate(struct kvm_vcpu *vcpu);
void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu);
void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu);
arm64: KVM: allow export and import of generic timer regs For correct guest suspend/resume behaviour we need to ensure we include the generic timer registers for 64 bit guests. As CONFIG_KVM_ARM_TIMER is always set for arm64 we don't need to worry about null implementations. However I have re-jigged the kvm_arm_timer_set/get_reg declarations to be in the common include/kvm/arm_arch_timer.h headers. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-07-04 22:54:14 +08:00
u64 kvm_arm_timer_get_reg(struct kvm_vcpu *, u64 regid);
int kvm_arm_timer_set_reg(struct kvm_vcpu *, u64 regid, u64 value);
KVM: arm/arm64: Decouple kvm timer functions from virtual timer Now that we have a separate structure for timer context, make functions generic so that they can work with any timer context, not just the virtual timer context. This does not change the virtual timer functionality. Signed-off-by: Jintack Lim <jintack@cs.columbia.edu> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-03 23:20:01 +08:00
bool kvm_timer_should_fire(struct arch_timer_context *timer_ctx);
arm/arm64: KVM: arch_timer: Only schedule soft timer on vcpu_block We currently schedule a soft timer every time we exit the guest if the timer did not expire while running the guest. This is really not necessary, because the only work we do in the timer work function is to kick the vcpu. Kicking the vcpu does two things: (1) If the vpcu thread is on a waitqueue, make it runnable and remove it from the waitqueue. (2) If the vcpu is running on a different physical CPU from the one doing the kick, it sends a reschedule IPI. The second case cannot happen, because the soft timer is only ever scheduled when the vcpu is not running. The first case is only relevant when the vcpu thread is on a waitqueue, which is only the case when the vcpu thread has called kvm_vcpu_block(). Therefore, we only need to make sure a timer is scheduled for kvm_vcpu_block(), which we do by encapsulating all calls to kvm_vcpu_block() with kvm_timer_{un}schedule calls. Additionally, we only schedule a soft timer if the timer is enabled and unmasked, since it is useless otherwise. Note that theoretically userspace can use the SET_ONE_REG interface to change registers that should cause the timer to fire, even if the vcpu is blocked without a scheduled timer, but this case was not supported before this patch and we leave it for future work for now. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-08-26 01:48:21 +08:00
void kvm_timer_schedule(struct kvm_vcpu *vcpu);
void kvm_timer_unschedule(struct kvm_vcpu *vcpu);
arm/arm64: KVM: Fix migration race in the arch timer When a VCPU is no longer running, we currently check to see if it has a timer scheduled in the future, and if it does, we schedule a host hrtimer to notify is in case the timer expires while the VCPU is still not running. When the hrtimer fires, we mask the guest's timer and inject the timer IRQ (still relying on the guest unmasking the time when it receives the IRQ). This is all good and fine, but when migration a VM (checkpoint/restore) this introduces a race. It is unlikely, but possible, for the following sequence of events to happen: 1. Userspace stops the VM 2. Hrtimer for VCPU is scheduled 3. Userspace checkpoints the VGIC state (no pending timer interrupts) 4. The hrtimer fires, schedules work in a workqueue 5. Workqueue function runs, masks the timer and injects timer interrupt 6. Userspace checkpoints the timer state (timer masked) At restore time, you end up with a masked timer without any timer interrupts and your guest halts never receiving timer interrupts. Fix this by only kicking the VCPU in the workqueue function, and sample the expired state of the timer when entering the guest again and inject the interrupt and mask the timer only then. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-03-14 01:02:55 +08:00
KVM: arm/arm64: timer: Add active state caching Programming the active state in the (re)distributor can be an expensive operation so it makes some sense to try and reduce the number of accesses as much as possible. So far, we program the active state on each VM entry, but there is some opportunity to do less. An obvious solution is to cache the active state in memory, and only program it in the HW when conditions change. But because the HW can also change things under our feet (the active state can transition from 1 to 0 when the guest does an EOI), some precautions have to be taken, which amount to only caching an "inactive" state, and always programing it otherwise. With this in place, we observe a reduction of around 700 cycles on a 2GHz GICv2 platform for a NULL hypercall. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-01-30 03:04:48 +08:00
void kvm_timer_vcpu_put(struct kvm_vcpu *vcpu);
KVM: arm64: Access CNTHCTL_EL2 bit fields correctly on VHE systems Current KVM world switch code is unintentionally setting wrong bits to CNTHCTL_EL2 when E2H == 1, which may allow guest OS to access physical timer. Bit positions of CNTHCTL_EL2 are changing depending on HCR_EL2.E2H bit. EL1PCEN and EL1PCTEN are 1st and 0th bits when E2H is not set, but they are 11th and 10th bits respectively when E2H is set. In fact, on VHE we only need to set those bits once, not for every world switch. This is because the host kernel runs in EL2 with HCR_EL2.TGE == 1, which makes those bits have no effect for the host kernel execution. So we just set those bits once for guests, and that's it. Signed-off-by: Jintack Lim <jintack@cs.columbia.edu> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-12-02 03:32:05 +08:00
void kvm_timer_init_vhe(void);
KVM: arm/arm64: Abstract virtual timer context into separate structure Abstract virtual timer context into a separate structure and change all callers referring to timer registers, irq state and so on. No change in functionality. This is about to become very handy when adding the EL1 physical timer. Signed-off-by: Jintack Lim <jintack@cs.columbia.edu> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-03 23:19:59 +08:00
#define vcpu_vtimer(v) (&(v)->arch.timer_cpu.vtimer)
KVM: arm/arm64: Add the EL1 physical timer context Add the EL1 physical timer context. Signed-off-by: Jintack Lim <jintack@cs.columbia.edu> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-03 23:20:02 +08:00
#define vcpu_ptimer(v) (&(v)->arch.timer_cpu.ptimer)
ARM: KVM: arch_timers: Add guest timer core support Add some the architected timer related infrastructure, and support timer interrupt injection, which can happen as a resultof three possible events: - The virtual timer interrupt has fired while we were still executing the guest - The timer interrupt hasn't fired, but it expired while we were doing the world switch - A hrtimer we programmed earlier has fired Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2013-01-24 02:21:58 +08:00
#endif
Reference in New Issue Copy Permalink