Re: [PATCH 29/36] cpuidle,xenpv: Make more PARAVIRT_XXL noinstr clean

["Srivatsa S. Bhat" <srivatsa@xxxxxxxxxxxxx>]

On 6/8/22 4:27 PM, Peter Zijlstra wrote:
> vmlinux.o: warning: objtool: acpi_idle_enter_s2idle+0xde: call to wbinvd() 
> leaves .noinstr.text section
> vmlinux.o: warning: objtool: default_idle+0x4: call to arch_safe_halt() 
> leaves .noinstr.text section
> vmlinux.o: warning: objtool: xen_safe_halt+0xa: call to 
> HYPERVISOR_sched_op.constprop.0() leaves .noinstr.text section
> 
> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>

Reviewed-by: Srivatsa S. Bhat (VMware) <srivatsa@xxxxxxxxxxxxx>


Regards,
Srivatsa
VMware Photon OS

> ---
>  arch/x86/include/asm/paravirt.h      |    6 ++++--
>  arch/x86/include/asm/special_insns.h |    4 ++--
>  arch/x86/include/asm/xen/hypercall.h |    2 +-
>  arch/x86/kernel/paravirt.c           |   14 ++++++++++++--
>  arch/x86/xen/enlighten_pv.c          |    2 +-
>  arch/x86/xen/irq.c                   |    2 +-
>  6 files changed, 21 insertions(+), 9 deletions(-)
> 
> --- a/arch/x86/include/asm/paravirt.h
> +++ b/arch/x86/include/asm/paravirt.h
> @@ -168,7 +168,7 @@ static inline void __write_cr4(unsigned
>       PVOP_VCALL1(cpu.write_cr4, x);
>  }
>  
> -static inline void arch_safe_halt(void)
> +static __always_inline void arch_safe_halt(void)
>  {
>       PVOP_VCALL0(irq.safe_halt);
>  }
> @@ -178,7 +178,9 @@ static inline void halt(void)
>       PVOP_VCALL0(irq.halt);
>  }
>  
> -static inline void wbinvd(void)
> +extern noinstr void pv_native_wbinvd(void);
> +
> +static __always_inline void wbinvd(void)
>  {
>       PVOP_ALT_VCALL0(cpu.wbinvd, "wbinvd", ALT_NOT(X86_FEATURE_XENPV));
>  }
> --- a/arch/x86/include/asm/special_insns.h
> +++ b/arch/x86/include/asm/special_insns.h
> @@ -115,7 +115,7 @@ static inline void wrpkru(u32 pkru)
>  }
>  #endif
>  
> -static inline void native_wbinvd(void)
> +static __always_inline void native_wbinvd(void)
>  {
>       asm volatile("wbinvd": : :"memory");
>  }
> @@ -179,7 +179,7 @@ static inline void __write_cr4(unsigned
>       native_write_cr4(x);
>  }
>  
> -static inline void wbinvd(void)
> +static __always_inline void wbinvd(void)
>  {
>       native_wbinvd();
>  }
> --- a/arch/x86/include/asm/xen/hypercall.h
> +++ b/arch/x86/include/asm/xen/hypercall.h
> @@ -382,7 +382,7 @@ MULTI_stack_switch(struct multicall_entr
>  }
>  #endif
>  
> -static inline int
> +static __always_inline int
>  HYPERVISOR_sched_op(int cmd, void *arg)
>  {
>       return _hypercall2(int, sched_op, cmd, arg);
> --- a/arch/x86/kernel/paravirt.c
> +++ b/arch/x86/kernel/paravirt.c
> @@ -233,6 +233,11 @@ static noinstr void pv_native_set_debugr
>       native_set_debugreg(regno, val);
>  }
>  
> +noinstr void pv_native_wbinvd(void)
> +{
> +     native_wbinvd();
> +}
> +
>  static noinstr void pv_native_irq_enable(void)
>  {
>       native_irq_enable();
> @@ -242,6 +247,11 @@ static noinstr void pv_native_irq_disabl
>  {
>       native_irq_disable();
>  }
> +
> +static noinstr void pv_native_safe_halt(void)
> +{
> +     native_safe_halt();
> +}
>  #endif
>  
>  enum paravirt_lazy_mode paravirt_get_lazy_mode(void)
> @@ -273,7 +283,7 @@ struct paravirt_patch_template pv_ops =
>       .cpu.read_cr0           = native_read_cr0,
>       .cpu.write_cr0          = native_write_cr0,
>       .cpu.write_cr4          = native_write_cr4,
> -     .cpu.wbinvd             = native_wbinvd,
> +     .cpu.wbinvd             = pv_native_wbinvd,
>       .cpu.read_msr           = native_read_msr,
>       .cpu.write_msr          = native_write_msr,
>       .cpu.read_msr_safe      = native_read_msr_safe,
> @@ -307,7 +317,7 @@ struct paravirt_patch_template pv_ops =
>       .irq.save_fl            = __PV_IS_CALLEE_SAVE(native_save_fl),
>       .irq.irq_disable        = __PV_IS_CALLEE_SAVE(pv_native_irq_disable),
>       .irq.irq_enable         = __PV_IS_CALLEE_SAVE(pv_native_irq_enable),
> -     .irq.safe_halt          = native_safe_halt,
> +     .irq.safe_halt          = pv_native_safe_halt,
>       .irq.halt               = native_halt,
>  #endif /* CONFIG_PARAVIRT_XXL */
>  
> --- a/arch/x86/xen/enlighten_pv.c
> +++ b/arch/x86/xen/enlighten_pv.c
> @@ -1019,7 +1019,7 @@ static const typeof(pv_ops) xen_cpu_ops
>  
>               .write_cr4 = xen_write_cr4,
>  
> -             .wbinvd = native_wbinvd,
> +             .wbinvd = pv_native_wbinvd,
>  
>               .read_msr = xen_read_msr,
>               .write_msr = xen_write_msr,
> --- a/arch/x86/xen/irq.c
> +++ b/arch/x86/xen/irq.c
> @@ -24,7 +24,7 @@ noinstr void xen_force_evtchn_callback(v
>       (void)HYPERVISOR_xen_version(0, NULL);
>  }
>  
> -static void xen_safe_halt(void)
> +static noinstr void xen_safe_halt(void)
>  {
>       /* Blocking includes an implicit local_irq_enable(). */
>       if (HYPERVISOR_sched_op(SCHEDOP_block, NULL) != 0)
> 
>