[patch V3 21/23] context_tracking: Make guest_enter/exit_irqoff() .noinstr ready

[Thomas Gleixner]

Mark the functions __always_inline and add the annotations for the "safe"
calls into regular text sections where RCU is watching.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Tom Lendacky <thomas.lendacky@xxxxxxx>
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: kvm@xxxxxxxxxxxxxxx
---
 include/linux/context_tracking.h |   21 ++++++++++++++++-----
 1 file changed, 16 insertions(+), 5 deletions(-)

--- a/include/linux/context_tracking.h
+++ b/include/linux/context_tracking.h
@@ -101,12 +101,14 @@ static inline void context_tracking_init
 
 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
 /* must be called with irqs disabled */
-static inline void guest_enter_irqoff(void)
+static __always_inline void guest_enter_irqoff(void)
 {
+	instr_begin();
 	if (vtime_accounting_enabled_this_cpu())
 		vtime_guest_enter(current);
 	else
 		current->flags |= PF_VCPU;
+	instr_end();
 
 	if (context_tracking_enabled())
 		__context_tracking_enter(CONTEXT_GUEST);
@@ -118,39 +120,48 @@ static inline void guest_enter_irqoff(vo
 	 * one time slice). Lets treat guest mode as quiescent state, just like
 	 * we do with user-mode execution.
 	 */
-	if (!context_tracking_enabled_this_cpu())
+	if (!context_tracking_enabled_this_cpu()) {
+		instr_begin();
 		rcu_virt_note_context_switch(smp_processor_id());
+		instr_end();
+	}
 }
 
-static inline void guest_exit_irqoff(void)
+static __always_inline void guest_exit_irqoff(void)
 {
 	if (context_tracking_enabled())
 		__context_tracking_exit(CONTEXT_GUEST);
 
+	instr_begin();
 	if (vtime_accounting_enabled_this_cpu())
 		vtime_guest_exit(current);
 	else
 		current->flags &= ~PF_VCPU;
+	instr_end();
 }
 
 #else
-static inline void guest_enter_irqoff(void)
+static __always_inline void guest_enter_irqoff(void)
 {
 	/*
 	 * This is running in ioctl context so its safe
 	 * to assume that it's the stime pending cputime
 	 * to flush.
 	 */
+	instr_begin();
 	vtime_account_kernel(current);
 	current->flags |= PF_VCPU;
 	rcu_virt_note_context_switch(smp_processor_id());
+	instr_end();
 }
 
-static inline void guest_exit_irqoff(void)
+static __always_inline void guest_exit_irqoff(void)
 {
+	instr_begin();
 	/* Flush the guest cputime we spent on the guest */
 	vtime_account_kernel(current);
 	current->flags &= ~PF_VCPU;
+	instr_end();
 }
 #endif /* CONFIG_VIRT_CPU_ACCOUNTING_GEN */