Re: [PATCH 03/10] Drivers: hv: Redo Hyper-V synthetic MSR get/set functions

From: Boqun Feng
Date: Sun Feb 21 2021 - 22:26:36 EST


On Wed, Jan 27, 2021 at 12:23:38PM -0800, Michael Kelley wrote:
> Current code defines a separate get and set macro for each Hyper-V
> synthetic MSR used by the VMbus driver. Furthermore, the get macro
> can't be converted to a standard function because the second argument
> is modified in place, which is somewhat bad form.
>
> Redo this by providing a single get and a single set function that
> take a parameter specifying the MSR to be operated on. Fixup usage
> of the get function. Calling locations are no more complex than before,
> but the code under arch/x86 and the upcoming code under arch/arm64
> is significantly simplified.
>
> Also standardize the names of Hyper-V synthetic MSRs that are
> architecture neutral. But keep the old x86-specific names as aliases
> that can be removed later when all references (particularly in KVM
> code) have been cleaned up in a separate patch series.
>
> No functional change.
>
> Signed-off-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>

Reviewed-by: Boqun Feng <boqun.feng@xxxxxxxxx>

Regards,
Boqun

> ---
> arch/x86/hyperv/hv_init.c | 2 +-
> arch/x86/include/asm/hyperv-tlfs.h | 102 +++++++++++++++++++++++--------------
> arch/x86/include/asm/mshyperv.h | 39 ++++----------
> drivers/clocksource/hyperv_timer.c | 26 +++++-----
> drivers/hv/hv.c | 37 ++++++++------
> drivers/hv/vmbus_drv.c | 2 +-
> include/asm-generic/mshyperv.h | 2 +-
> 7 files changed, 110 insertions(+), 100 deletions(-)
>
> diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
> index 2d1688e..9b2cdbe 100644
> --- a/arch/x86/hyperv/hv_init.c
> +++ b/arch/x86/hyperv/hv_init.c
> @@ -58,7 +58,7 @@ static int hv_cpu_init(unsigned int cpu)
> return -ENOMEM;
> *input_arg = page_address(pg);
>
> - hv_get_vp_index(msr_vp_index);
> + msr_vp_index = hv_get_register(HV_REGISTER_VP_INDEX);
>
> hv_vp_index[smp_processor_id()] = msr_vp_index;
>
> diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h
> index dd74066..545026e 100644
> --- a/arch/x86/include/asm/hyperv-tlfs.h
> +++ b/arch/x86/include/asm/hyperv-tlfs.h
> @@ -131,7 +131,7 @@
> #define HV_X64_MSR_HYPERCALL 0x40000001
>
> /* MSR used to provide vcpu index */
> -#define HV_X64_MSR_VP_INDEX 0x40000002
> +#define HV_REGISTER_VP_INDEX 0x40000002
>
> /* MSR used to reset the guest OS. */
> #define HV_X64_MSR_RESET 0x40000003
> @@ -140,10 +140,10 @@
> #define HV_X64_MSR_VP_RUNTIME 0x40000010
>
> /* MSR used to read the per-partition time reference counter */
> -#define HV_X64_MSR_TIME_REF_COUNT 0x40000020
> +#define HV_REGISTER_TIME_REF_COUNT 0x40000020
>
> /* A partition's reference time stamp counter (TSC) page */
> -#define HV_X64_MSR_REFERENCE_TSC 0x40000021
> +#define HV_REGISTER_REFERENCE_TSC 0x40000021
>
> /* MSR used to retrieve the TSC frequency */
> #define HV_X64_MSR_TSC_FREQUENCY 0x40000022
> @@ -158,50 +158,50 @@
> #define HV_X64_MSR_VP_ASSIST_PAGE 0x40000073
>
> /* Define synthetic interrupt controller model specific registers. */
> -#define HV_X64_MSR_SCONTROL 0x40000080
> -#define HV_X64_MSR_SVERSION 0x40000081
> -#define HV_X64_MSR_SIEFP 0x40000082
> -#define HV_X64_MSR_SIMP 0x40000083
> -#define HV_X64_MSR_EOM 0x40000084
> -#define HV_X64_MSR_SINT0 0x40000090
> -#define HV_X64_MSR_SINT1 0x40000091
> -#define HV_X64_MSR_SINT2 0x40000092
> -#define HV_X64_MSR_SINT3 0x40000093
> -#define HV_X64_MSR_SINT4 0x40000094
> -#define HV_X64_MSR_SINT5 0x40000095
> -#define HV_X64_MSR_SINT6 0x40000096
> -#define HV_X64_MSR_SINT7 0x40000097
> -#define HV_X64_MSR_SINT8 0x40000098
> -#define HV_X64_MSR_SINT9 0x40000099
> -#define HV_X64_MSR_SINT10 0x4000009A
> -#define HV_X64_MSR_SINT11 0x4000009B
> -#define HV_X64_MSR_SINT12 0x4000009C
> -#define HV_X64_MSR_SINT13 0x4000009D
> -#define HV_X64_MSR_SINT14 0x4000009E
> -#define HV_X64_MSR_SINT15 0x4000009F
> +#define HV_REGISTER_SCONTROL 0x40000080
> +#define HV_REGISTER_SVERSION 0x40000081
> +#define HV_REGISTER_SIEFP 0x40000082
> +#define HV_REGISTER_SIMP 0x40000083
> +#define HV_REGISTER_EOM 0x40000084
> +#define HV_REGISTER_SINT0 0x40000090
> +#define HV_REGISTER_SINT1 0x40000091
> +#define HV_REGISTER_SINT2 0x40000092
> +#define HV_REGISTER_SINT3 0x40000093
> +#define HV_REGISTER_SINT4 0x40000094
> +#define HV_REGISTER_SINT5 0x40000095
> +#define HV_REGISTER_SINT6 0x40000096
> +#define HV_REGISTER_SINT7 0x40000097
> +#define HV_REGISTER_SINT8 0x40000098
> +#define HV_REGISTER_SINT9 0x40000099
> +#define HV_REGISTER_SINT10 0x4000009A
> +#define HV_REGISTER_SINT11 0x4000009B
> +#define HV_REGISTER_SINT12 0x4000009C
> +#define HV_REGISTER_SINT13 0x4000009D
> +#define HV_REGISTER_SINT14 0x4000009E
> +#define HV_REGISTER_SINT15 0x4000009F
>
> /*
> * Synthetic Timer MSRs. Four timers per vcpu.
> */
> -#define HV_X64_MSR_STIMER0_CONFIG 0x400000B0
> -#define HV_X64_MSR_STIMER0_COUNT 0x400000B1
> -#define HV_X64_MSR_STIMER1_CONFIG 0x400000B2
> -#define HV_X64_MSR_STIMER1_COUNT 0x400000B3
> -#define HV_X64_MSR_STIMER2_CONFIG 0x400000B4
> -#define HV_X64_MSR_STIMER2_COUNT 0x400000B5
> -#define HV_X64_MSR_STIMER3_CONFIG 0x400000B6
> -#define HV_X64_MSR_STIMER3_COUNT 0x400000B7
> +#define HV_REGISTER_STIMER0_CONFIG 0x400000B0
> +#define HV_REGISTER_STIMER0_COUNT 0x400000B1
> +#define HV_REGISTER_STIMER1_CONFIG 0x400000B2
> +#define HV_REGISTER_STIMER1_COUNT 0x400000B3
> +#define HV_REGISTER_STIMER2_CONFIG 0x400000B4
> +#define HV_REGISTER_STIMER2_COUNT 0x400000B5
> +#define HV_REGISTER_STIMER3_CONFIG 0x400000B6
> +#define HV_REGISTER_STIMER3_COUNT 0x400000B7
>
> /* Hyper-V guest idle MSR */
> #define HV_X64_MSR_GUEST_IDLE 0x400000F0
>
> /* Hyper-V guest crash notification MSR's */
> -#define HV_X64_MSR_CRASH_P0 0x40000100
> -#define HV_X64_MSR_CRASH_P1 0x40000101
> -#define HV_X64_MSR_CRASH_P2 0x40000102
> -#define HV_X64_MSR_CRASH_P3 0x40000103
> -#define HV_X64_MSR_CRASH_P4 0x40000104
> -#define HV_X64_MSR_CRASH_CTL 0x40000105
> +#define HV_REGISTER_CRASH_P0 0x40000100
> +#define HV_REGISTER_CRASH_P1 0x40000101
> +#define HV_REGISTER_CRASH_P2 0x40000102
> +#define HV_REGISTER_CRASH_P3 0x40000103
> +#define HV_REGISTER_CRASH_P4 0x40000104
> +#define HV_REGISTER_CRASH_CTL 0x40000105
>
> /* TSC emulation after migration */
> #define HV_X64_MSR_REENLIGHTENMENT_CONTROL 0x40000106
> @@ -211,6 +211,32 @@
> /* TSC invariant control */
> #define HV_X64_MSR_TSC_INVARIANT_CONTROL 0x40000118
>
> +/* Register name aliases for architecture independence */
> +#define HV_X64_MSR_STIMER0_COUNT HV_REGISTER_STIMER0_COUNT
> +#define HV_X64_MSR_STIMER0_CONFIG HV_REGISTER_STIMER0_CONFIG
> +#define HV_X64_MSR_STIMER1_COUNT HV_REGISTER_STIMER1_COUNT
> +#define HV_X64_MSR_STIMER1_CONFIG HV_REGISTER_STIMER1_CONFIG
> +#define HV_X64_MSR_STIMER2_COUNT HV_REGISTER_STIMER2_COUNT
> +#define HV_X64_MSR_STIMER2_CONFIG HV_REGISTER_STIMER2_CONFIG
> +#define HV_X64_MSR_STIMER3_COUNT HV_REGISTER_STIMER3_COUNT
> +#define HV_X64_MSR_STIMER3_CONFIG HV_REGISTER_STIMER3_CONFIG
> +#define HV_X64_MSR_SCONTROL HV_REGISTER_SCONTROL
> +#define HV_X64_MSR_SVERSION HV_REGISTER_SVERSION
> +#define HV_X64_MSR_SIMP HV_REGISTER_SIMP
> +#define HV_X64_MSR_SIEFP HV_REGISTER_SIEFP
> +#define HV_X64_MSR_VP_INDEX HV_REGISTER_VP_INDEX
> +#define HV_X64_MSR_EOM HV_REGISTER_EOM
> +#define HV_X64_MSR_SINT0 HV_REGISTER_SINT0
> +#define HV_X64_MSR_SINT15 HV_REGISTER_SINT15
> +#define HV_X64_MSR_CRASH_P0 HV_REGISTER_CRASH_P0
> +#define HV_X64_MSR_CRASH_P1 HV_REGISTER_CRASH_P1
> +#define HV_X64_MSR_CRASH_P2 HV_REGISTER_CRASH_P2
> +#define HV_X64_MSR_CRASH_P3 HV_REGISTER_CRASH_P3
> +#define HV_X64_MSR_CRASH_P4 HV_REGISTER_CRASH_P4
> +#define HV_X64_MSR_CRASH_CTL HV_REGISTER_CRASH_CTL
> +#define HV_X64_MSR_TIME_REF_COUNT HV_REGISTER_TIME_REF_COUNT
> +#define HV_X64_MSR_REFERENCE_TSC HV_REGISTER_REFERENCE_TSC
> +
> /*
> * Declare the MSR used to setup pages used to communicate with the hypervisor.
> */
> diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
> index 29d0414..eba637d1 100644
> --- a/arch/x86/include/asm/mshyperv.h
> +++ b/arch/x86/include/asm/mshyperv.h
> @@ -14,41 +14,22 @@ typedef int (*hyperv_fill_flush_list_func)(
> struct hv_guest_mapping_flush_list *flush,
> void *data);
>
> -#define hv_init_timer(timer, tick) \
> - wrmsrl(HV_X64_MSR_STIMER0_COUNT + (2*timer), tick)
> -#define hv_init_timer_config(timer, val) \
> - wrmsrl(HV_X64_MSR_STIMER0_CONFIG + (2*timer), val)
> -
> -#define hv_get_simp(val) rdmsrl(HV_X64_MSR_SIMP, val)
> -#define hv_set_simp(val) wrmsrl(HV_X64_MSR_SIMP, val)
> -
> -#define hv_get_siefp(val) rdmsrl(HV_X64_MSR_SIEFP, val)
> -#define hv_set_siefp(val) wrmsrl(HV_X64_MSR_SIEFP, val)
> -
> -#define hv_get_synic_state(val) rdmsrl(HV_X64_MSR_SCONTROL, val)
> -#define hv_set_synic_state(val) wrmsrl(HV_X64_MSR_SCONTROL, val)
> +static inline void hv_set_register(unsigned int reg, u64 value)
> +{
> + wrmsrl(reg, value);
> +}
>
> -#define hv_get_vp_index(index) rdmsrl(HV_X64_MSR_VP_INDEX, index)
> +static inline u64 hv_get_register(unsigned int reg)
> +{
> + u64 value;
>
> -#define hv_signal_eom() wrmsrl(HV_X64_MSR_EOM, 0)
> + rdmsrl(reg, value);
> + return value;
> +}
>
> -#define hv_get_synint_state(int_num, val) \
> - rdmsrl(HV_X64_MSR_SINT0 + int_num, val)
> -#define hv_set_synint_state(int_num, val) \
> - wrmsrl(HV_X64_MSR_SINT0 + int_num, val)
> #define hv_recommend_using_aeoi() \
> (!(ms_hyperv.hints & HV_DEPRECATING_AEOI_RECOMMENDED))
>
> -#define hv_get_crash_ctl(val) \
> - rdmsrl(HV_X64_MSR_CRASH_CTL, val)
> -
> -#define hv_get_time_ref_count(val) \
> - rdmsrl(HV_X64_MSR_TIME_REF_COUNT, val)
> -
> -#define hv_get_reference_tsc(val) \
> - rdmsrl(HV_X64_MSR_REFERENCE_TSC, val)
> -#define hv_set_reference_tsc(val) \
> - wrmsrl(HV_X64_MSR_REFERENCE_TSC, val)
> #define hv_set_clocksource_vdso(val) \
> ((val).vdso_clock_mode = VDSO_CLOCKMODE_HVCLOCK)
> #define hv_enable_vdso_clocksource() \
> diff --git a/drivers/clocksource/hyperv_timer.c b/drivers/clocksource/hyperv_timer.c
> index ba04cb3..9425308 100644
> --- a/drivers/clocksource/hyperv_timer.c
> +++ b/drivers/clocksource/hyperv_timer.c
> @@ -68,14 +68,14 @@ static int hv_ce_set_next_event(unsigned long delta,
>
> current_tick = hv_read_reference_counter();
> current_tick += delta;
> - hv_init_timer(0, current_tick);
> + hv_set_register(HV_REGISTER_STIMER0_COUNT, current_tick);
> return 0;
> }
>
> static int hv_ce_shutdown(struct clock_event_device *evt)
> {
> - hv_init_timer(0, 0);
> - hv_init_timer_config(0, 0);
> + hv_set_register(HV_REGISTER_STIMER0_COUNT, 0);
> + hv_set_register(HV_REGISTER_STIMER0_CONFIG, 0);
> if (direct_mode_enabled)
> hv_disable_stimer0_percpu_irq(stimer0_irq);
>
> @@ -105,7 +105,7 @@ static int hv_ce_set_oneshot(struct clock_event_device *evt)
> timer_cfg.direct_mode = 0;
> timer_cfg.sintx = stimer0_message_sint;
> }
> - hv_init_timer_config(0, timer_cfg.as_uint64);
> + hv_set_register(HV_REGISTER_STIMER0_CONFIG, timer_cfg.as_uint64);
> return 0;
> }
>
> @@ -331,7 +331,7 @@ static u64 notrace read_hv_clock_tsc(void)
> u64 current_tick = hv_read_tsc_page(hv_get_tsc_page());
>
> if (current_tick == U64_MAX)
> - hv_get_time_ref_count(current_tick);
> + current_tick = hv_get_register(HV_REGISTER_TIME_REF_COUNT);
>
> return current_tick;
> }
> @@ -352,9 +352,9 @@ static void suspend_hv_clock_tsc(struct clocksource *arg)
> u64 tsc_msr;
>
> /* Disable the TSC page */
> - hv_get_reference_tsc(tsc_msr);
> + tsc_msr = hv_get_register(HV_REGISTER_REFERENCE_TSC);
> tsc_msr &= ~BIT_ULL(0);
> - hv_set_reference_tsc(tsc_msr);
> + hv_set_register(HV_REGISTER_REFERENCE_TSC, tsc_msr);
> }
>
>
> @@ -364,10 +364,10 @@ static void resume_hv_clock_tsc(struct clocksource *arg)
> u64 tsc_msr;
>
> /* Re-enable the TSC page */
> - hv_get_reference_tsc(tsc_msr);
> + tsc_msr = hv_get_register(HV_REGISTER_REFERENCE_TSC);
> tsc_msr &= GENMASK_ULL(11, 0);
> tsc_msr |= BIT_ULL(0) | (u64)phys_addr;
> - hv_set_reference_tsc(tsc_msr);
> + hv_set_register(HV_REGISTER_REFERENCE_TSC, tsc_msr);
> }
>
> static int hv_cs_enable(struct clocksource *cs)
> @@ -389,14 +389,12 @@ static int hv_cs_enable(struct clocksource *cs)
>
> static u64 notrace read_hv_clock_msr(void)
> {
> - u64 current_tick;
> /*
> * Read the partition counter to get the current tick count. This count
> * is set to 0 when the partition is created and is incremented in
> * 100 nanosecond units.
> */
> - hv_get_time_ref_count(current_tick);
> - return current_tick;
> + return hv_get_register(HV_REGISTER_TIME_REF_COUNT);
> }
>
> static u64 notrace read_hv_clock_msr_cs(struct clocksource *arg)
> @@ -436,10 +434,10 @@ static bool __init hv_init_tsc_clocksource(void)
> * (which already has at least the low 12 bits set to zero since
> * it is page aligned). Also set the "enable" bit, which is bit 0.
> */
> - hv_get_reference_tsc(tsc_msr);
> + tsc_msr = hv_get_register(HV_REGISTER_REFERENCE_TSC);
> tsc_msr &= GENMASK_ULL(11, 0);
> tsc_msr = tsc_msr | 0x1 | (u64)phys_addr;
> - hv_set_reference_tsc(tsc_msr);
> + hv_set_register(HV_REGISTER_REFERENCE_TSC, tsc_msr);
>
> hv_set_clocksource_vdso(hyperv_cs_tsc);
> clocksource_register_hz(&hyperv_cs_tsc, NSEC_PER_SEC/100);
> diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c
> index cca8d5e..0c1fa69 100644
> --- a/drivers/hv/hv.c
> +++ b/drivers/hv/hv.c
> @@ -198,34 +198,36 @@ void hv_synic_enable_regs(unsigned int cpu)
> union hv_synic_scontrol sctrl;
>
> /* Setup the Synic's message page */
> - hv_get_simp(simp.as_uint64);
> + simp.as_uint64 = hv_get_register(HV_REGISTER_SIMP);
> simp.simp_enabled = 1;
> simp.base_simp_gpa = virt_to_phys(hv_cpu->synic_message_page)
> >> HV_HYP_PAGE_SHIFT;
>
> - hv_set_simp(simp.as_uint64);
> + hv_set_register(HV_REGISTER_SIMP, simp.as_uint64);
>
> /* Setup the Synic's event page */
> - hv_get_siefp(siefp.as_uint64);
> + siefp.as_uint64 = hv_get_register(HV_REGISTER_SIEFP);
> siefp.siefp_enabled = 1;
> siefp.base_siefp_gpa = virt_to_phys(hv_cpu->synic_event_page)
> >> HV_HYP_PAGE_SHIFT;
>
> - hv_set_siefp(siefp.as_uint64);
> + hv_set_register(HV_REGISTER_SIEFP, siefp.as_uint64);
>
> /* Setup the shared SINT. */
> - hv_get_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
> + shared_sint.as_uint64 = hv_get_register(HV_REGISTER_SINT0 +
> + VMBUS_MESSAGE_SINT);
>
> shared_sint.vector = hv_get_vector();
> shared_sint.masked = false;
> shared_sint.auto_eoi = hv_recommend_using_aeoi();
> - hv_set_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
> + hv_set_register(HV_REGISTER_SINT0 + VMBUS_MESSAGE_SINT,
> + shared_sint.as_uint64);
>
> /* Enable the global synic bit */
> - hv_get_synic_state(sctrl.as_uint64);
> + sctrl.as_uint64 = hv_get_register(HV_REGISTER_SCONTROL);
> sctrl.enable = 1;
>
> - hv_set_synic_state(sctrl.as_uint64);
> + hv_set_register(HV_REGISTER_SCONTROL, sctrl.as_uint64);
> }
>
> int hv_synic_init(unsigned int cpu)
> @@ -247,32 +249,35 @@ void hv_synic_disable_regs(unsigned int cpu)
> union hv_synic_siefp siefp;
> union hv_synic_scontrol sctrl;
>
> - hv_get_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
> + shared_sint.as_uint64 = hv_get_register(HV_REGISTER_SINT0 +
> + VMBUS_MESSAGE_SINT);
>
> shared_sint.masked = 1;
>
> /* Need to correctly cleanup in the case of SMP!!! */
> /* Disable the interrupt */
> - hv_set_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
> + hv_set_register(HV_REGISTER_SINT0 + VMBUS_MESSAGE_SINT,
> + shared_sint.as_uint64);
>
> - hv_get_simp(simp.as_uint64);
> + simp.as_uint64 = hv_get_register(HV_REGISTER_SIMP);
> simp.simp_enabled = 0;
> simp.base_simp_gpa = 0;
>
> - hv_set_simp(simp.as_uint64);
> + hv_set_register(HV_REGISTER_SIMP, simp.as_uint64);
>
> - hv_get_siefp(siefp.as_uint64);
> + siefp.as_uint64 = hv_get_register(HV_REGISTER_SIEFP);
> siefp.siefp_enabled = 0;
> siefp.base_siefp_gpa = 0;
>
> - hv_set_siefp(siefp.as_uint64);
> + hv_set_register(HV_REGISTER_SIEFP, siefp.as_uint64);
>
> /* Disable the global synic bit */
> - hv_get_synic_state(sctrl.as_uint64);
> + sctrl.as_uint64 = hv_get_register(HV_REGISTER_SCONTROL);
> sctrl.enable = 0;
> - hv_set_synic_state(sctrl.as_uint64);
> + hv_set_register(HV_REGISTER_SCONTROL, sctrl.as_uint64);
> }
>
> +
> int hv_synic_cleanup(unsigned int cpu)
> {
> struct vmbus_channel *channel, *sc;
> diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
> index 502f8cd..089f165 100644
> --- a/drivers/hv/vmbus_drv.c
> +++ b/drivers/hv/vmbus_drv.c
> @@ -1494,7 +1494,7 @@ static int vmbus_bus_init(void)
> * Register for panic kmsg callback only if the right
> * capability is supported by the hypervisor.
> */
> - hv_get_crash_ctl(hyperv_crash_ctl);
> + hyperv_crash_ctl = hv_get_register(HV_REGISTER_CRASH_CTL);
> if (hyperv_crash_ctl & HV_CRASH_CTL_CRASH_NOTIFY_MSG)
> hv_kmsg_dump_register();
>
> diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
> index 762d3ac..10c97a9 100644
> --- a/include/asm-generic/mshyperv.h
> +++ b/include/asm-generic/mshyperv.h
> @@ -85,7 +85,7 @@ static inline void vmbus_signal_eom(struct hv_message *msg, u32 old_msg_type)
> * possibly deliver another msg from the
> * hypervisor
> */
> - hv_signal_eom();
> + hv_set_register(HV_REGISTER_EOM, 0);
> }
> }
>
> --
> 1.8.3.1
>