Pass in a PV clock's save/restore helpers when configuring sched_clock instead of relying on each PV clock to manually set the save/restore hooks. In addition to bringing sanity to the code, this will allow gracefully "rejecting" a PV sched_clock, e.g. when running as a CoCo guest that has access to a "secure" TSC.
No functional change intended. Signed-off-by: Sean Christopherson <[email protected]> --- arch/x86/include/asm/timer.h | 9 ++++++--- arch/x86/kernel/cpu/vmware.c | 7 ++----- arch/x86/kernel/kvmclock.c | 6 +++--- arch/x86/kernel/tsc.c | 5 ++++- arch/x86/xen/time.c | 5 ++--- drivers/clocksource/hyperv_timer.c | 6 ++---- 6 files changed, 19 insertions(+), 19 deletions(-) diff --git a/arch/x86/include/asm/timer.h b/arch/x86/include/asm/timer.h index fe41d40a9ae6..e97cd1ae03d1 100644 --- a/arch/x86/include/asm/timer.h +++ b/arch/x86/include/asm/timer.h @@ -14,11 +14,14 @@ extern int no_timer_check; extern bool using_native_sched_clock(void); #ifdef CONFIG_PARAVIRT -void __paravirt_set_sched_clock(u64 (*func)(void), bool stable); +void __paravirt_set_sched_clock(u64 (*func)(void), bool stable, + void (*save)(void), void (*restore)(void)); -static inline void paravirt_set_sched_clock(u64 (*func)(void)) +static inline void paravirt_set_sched_clock(u64 (*func)(void), + void (*save)(void), + void (*restore)(void)) { - __paravirt_set_sched_clock(func, true); + __paravirt_set_sched_clock(func, true, save, restore); } #endif diff --git a/arch/x86/kernel/cpu/vmware.c b/arch/x86/kernel/cpu/vmware.c index b5cb66ca022b..968de002975f 100644 --- a/arch/x86/kernel/cpu/vmware.c +++ b/arch/x86/kernel/cpu/vmware.c @@ -347,11 +347,8 @@ static void __init vmware_paravirt_ops_setup(void) vmware_cyc2ns_setup(); - if (vmw_sched_clock) { - paravirt_set_sched_clock(vmware_sched_clock); - x86_platform.save_sched_clock_state = NULL; - x86_platform.restore_sched_clock_state = NULL; - } + if (vmw_sched_clock) + paravirt_set_sched_clock(vmware_sched_clock, NULL, NULL); if (vmware_is_stealclock_available()) { has_steal_clock = true; diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c index 800c3d65f0af..962b6fcb5c60 100644 --- a/arch/x86/kernel/kvmclock.c +++ b/arch/x86/kernel/kvmclock.c @@ -137,7 +137,9 @@ static void kvm_restore_sched_clock_state(void) static inline void kvm_sched_clock_init(bool stable) { kvm_sched_clock_offset = kvm_clock_read(); - __paravirt_set_sched_clock(kvm_sched_clock_read, stable); + __paravirt_set_sched_clock(kvm_sched_clock_read, stable, + kvm_save_sched_clock_state, + kvm_restore_sched_clock_state); pr_info("kvm-clock: using sched offset of %llu cycles", kvm_sched_clock_offset); @@ -344,8 +346,6 @@ void __init kvmclock_init(void) #ifdef CONFIG_SMP x86_cpuinit.early_percpu_clock_init = kvm_setup_secondary_clock; #endif - x86_platform.save_sched_clock_state = kvm_save_sched_clock_state; - x86_platform.restore_sched_clock_state = kvm_restore_sched_clock_state; kvm_get_preset_lpj(); /* diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c index b14c4ada89a3..0114c63dfdd9 100644 --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -280,12 +280,15 @@ bool using_native_sched_clock(void) return static_call_query(pv_sched_clock) == native_sched_clock; } -void __paravirt_set_sched_clock(u64 (*func)(void), bool stable) +void __paravirt_set_sched_clock(u64 (*func)(void), bool stable, + void (*save)(void), void (*restore)(void)) { if (!stable) clear_sched_clock_stable(); static_call_update(pv_sched_clock, func); + x86_platform.save_sched_clock_state = save; + x86_platform.restore_sched_clock_state = restore; } #else u64 sched_clock_noinstr(void) __attribute__((alias("native_sched_clock"))); diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c index 21d366d01985..ee7095febfd1 100644 --- a/arch/x86/xen/time.c +++ b/arch/x86/xen/time.c @@ -567,13 +567,12 @@ static void __init xen_init_time_common(void) { xen_sched_clock_offset = xen_clocksource_read(); static_call_update(pv_steal_clock, xen_steal_clock); - paravirt_set_sched_clock(xen_sched_clock); + /* * Xen has paravirtualized suspend/resume and so doesn't use the common * x86 sched_clock save/restore hooks. */ - x86_platform.save_sched_clock_state = NULL; - x86_platform.restore_sched_clock_state = NULL; + paravirt_set_sched_clock(xen_sched_clock, NULL, NULL); tsc_register_calibration_routines(xen_tsc_khz, NULL); x86_platform.get_wallclock = xen_get_wallclock; diff --git a/drivers/clocksource/hyperv_timer.c b/drivers/clocksource/hyperv_timer.c index ac1d9f9c381c..dee59ce61c29 100644 --- a/drivers/clocksource/hyperv_timer.c +++ b/drivers/clocksource/hyperv_timer.c @@ -553,10 +553,8 @@ static void hv_restore_sched_clock_state(void) static __always_inline void hv_setup_sched_clock(void *sched_clock) { /* We're on x86/x64 *and* using PV ops */ - paravirt_set_sched_clock(sched_clock); - - x86_platform.save_sched_clock_state = hv_save_sched_clock_state; - x86_platform.restore_sched_clock_state = hv_restore_sched_clock_state; + paravirt_set_sched_clock(sched_clock, hv_save_sched_clock_state, + hv_restore_sched_clock_state); } #else /* !CONFIG_GENERIC_SCHED_CLOCK && !CONFIG_PARAVIRT */ static __always_inline void hv_setup_sched_clock(void *sched_clock) {} -- 2.54.0.563.g4f69b47b94-goog
