x86/paravirt: Remove the WBINVD callback

The pv_ops::cpu.wbinvd paravirt callback is a leftover of lguest times.
Today it is no longer needed, as all users use the native WBINVD
implementation.

Remove the callback and rename native_wbinvd() to wbinvd().

Signed-off-by: Juergen Gross <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

Author: jgross1

arch/x86/include/asm/paravirt.h

@@ -180,13 +180,6 @@ static inline void halt(void)
 	PVOP_VCALL0(irq.halt);
 }
 
-extern noinstr void pv_native_wbinvd(void);
-
-static __always_inline void wbinvd(void)
-{
-	PVOP_ALT_VCALL0(cpu.wbinvd, "wbinvd", ALT_NOT_XEN);
-}
-
 static inline u64 paravirt_read_msr(unsigned msr)
 {
 	return PVOP_CALL1(u64, cpu.read_msr, msr);

arch/x86/include/asm/paravirt_types.h

@@ -86,8 +86,6 @@ struct pv_cpu_ops {
 	void (*update_io_bitmap)(void);
 #endif
 
-	void (*wbinvd)(void);
-
 	/* cpuid emulation, mostly so that caps bits can be disabled */
 	void (*cpuid)(unsigned int *eax, unsigned int *ebx,
 		      unsigned int *ecx, unsigned int *edx);

arch/x86/include/asm/special_insns.h

@@ -115,7 +115,7 @@ static inline void wrpkru(u32 pkru)
 }
 #endif
 
-static __always_inline void native_wbinvd(void)
+static __always_inline void wbinvd(void)
 {
 	asm volatile("wbinvd": : :"memory");
 }
@@ -167,12 +167,6 @@ static inline void __write_cr4(unsigned long x)
 {
 	native_write_cr4(x);
 }
-
-static __always_inline void wbinvd(void)
-{
-	native_wbinvd();
-}
-
 #endif /* CONFIG_PARAVIRT_XXL */
 
 static __always_inline void clflush(volatile void *__p)

arch/x86/kernel/cpu/resctrl/pseudo_lock.c

@@ -459,7 +459,7 @@ static int pseudo_lock_fn(void *_rdtgrp)
 	 * increase likelihood that allocated cache portion will be filled
 	 * with associated memory.
 	 */
-	native_wbinvd();
+	wbinvd();
 
 	/*
 	 * Always called with interrupts enabled. By disabling interrupts

arch/x86/kernel/paravirt.c

@@ -116,11 +116,6 @@ static noinstr void pv_native_set_debugreg(int regno, unsigned long val)
 	native_set_debugreg(regno, val);
 }
 
-noinstr void pv_native_wbinvd(void)
-{
-	native_wbinvd();
-}
-
 static noinstr void pv_native_safe_halt(void)
 {
 	native_safe_halt();
@@ -148,7 +143,6 @@ 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		= pv_native_wbinvd,
 	.cpu.read_msr		= native_read_msr,
 	.cpu.write_msr		= native_write_msr,
 	.cpu.read_msr_safe	= native_read_msr_safe,

arch/x86/kernel/process.c

@@ -825,7 +825,7 @@ void __noreturn stop_this_cpu(void *dummy)
 	 * X86_FEATURE_SME due to cmdline options.
 	 */
 	if (c->extended_cpuid_level >= 0x8000001f && (cpuid_eax(0x8000001f) & BIT(0)))
-		native_wbinvd();
+		wbinvd();
 
 	/*
 	 * This brings a cache line back and dirties it, but
@@ -846,7 +846,7 @@ void __noreturn stop_this_cpu(void *dummy)
 		/*
 		 * Use native_halt() so that memory contents don't change
 		 * (stack usage and variables) after possibly issuing the
-		 * native_wbinvd() above.
+		 * wbinvd() above.
 		 */
 		native_halt();
 	}

arch/x86/xen/enlighten_pv.c

@@ -1161,8 +1161,6 @@ static const typeof(pv_ops) xen_cpu_ops __initconst = {
 
 		.write_cr4 = xen_write_cr4,
 
-		.wbinvd = pv_native_wbinvd,
-
 		.read_msr = xen_read_msr,
 		.write_msr = xen_write_msr,