[PATCH v2 1/2] x86/svm: Don't toggle local event delivery on stgi/clgi

[Ross Lagerwall <ross.lagerwall@xxxxxxxxxx>]

There is no need to explicitly enable/disable local event delivery on
stgi/clgi since HVM event delivery already takes into account the state
of the GIF (and IF). This ensures the behaviour is consistent regardless
of whether vGIF is used.

Fold the functions into the callers since they are now only a single
assignment.

Signed-off-by: Ross Lagerwall <ross.lagerwall@xxxxxxxxxx>
---

New in v2.

 xen/arch/x86/hvm/svm/nestedsvm.c | 26 +++++---------------------
 1 file changed, 5 insertions(+), 21 deletions(-)

diff --git a/xen/arch/x86/hvm/svm/nestedsvm.c b/xen/arch/x86/hvm/svm/nestedsvm.c
index ef6fa5d23b67..64fbfe8fa71f 100644
--- a/xen/arch/x86/hvm/svm/nestedsvm.c
+++ b/xen/arch/x86/hvm/svm/nestedsvm.c
@@ -19,22 +19,6 @@
 #define NSVM_ERROR_VVMCB        1
 #define NSVM_ERROR_VMENTRY      2
 
-static void
-nestedsvm_vcpu_clgi(struct vcpu *v)
-{
-    /* clear gif flag */
-    vcpu_nestedsvm(v).ns_gif = 0;
-    local_event_delivery_disable(); /* mask events for PV drivers */
-}
-
-static void
-nestedsvm_vcpu_stgi(struct vcpu *v)
-{
-    /* enable gif flag */
-    vcpu_nestedsvm(v).ns_gif = 1;
-    local_event_delivery_enable(); /* unmask events for PV drivers */
-}
-
 int nestedsvm_vmcb_map(struct vcpu *v, uint64_t vmcbaddr)
 {
     struct nestedvcpu *nv = &vcpu_nestedhvm(v);
@@ -161,7 +145,7 @@ int cf_check nsvm_vcpu_reset(struct vcpu *v)
 
     svm->ns_iomap = NULL;
 
-    nestedsvm_vcpu_stgi(v);
+    svm->ns_gif = 1;
     return 0;
 }
 
@@ -667,7 +651,7 @@ nsvm_vcpu_vmentry(struct vcpu *v, struct cpu_user_regs 
*regs,
         return ret;
     }
 
-    nestedsvm_vcpu_stgi(v);
+    svm->ns_gif = 1;
     return 0;
 }
 
@@ -1214,7 +1198,7 @@ nestedsvm_vmexit_defer(struct vcpu *v,
     if ( vmcb->_vintr.fields.vgif_enable )
         vmcb->_vintr.fields.vgif = 0;
     else
-        nestedsvm_vcpu_clgi(v);
+        svm->ns_gif = 0;
 
     svm->ns_vmexit.exitcode = exitcode;
     svm->ns_vmexit.exitinfo1 = exitinfo1;
@@ -1502,7 +1486,7 @@ void svm_vmexit_do_stgi(struct cpu_user_regs *regs, 
struct vcpu *v)
     if ( (inst_len = svm_get_insn_len(v, INSTR_STGI)) == 0 )
         return;
 
-    nestedsvm_vcpu_stgi(v);
+    vcpu_nestedsvm(v).ns_gif = 1;
 
     __update_guest_eip(regs, inst_len);
 }
@@ -1523,7 +1507,7 @@ void svm_vmexit_do_clgi(struct cpu_user_regs *regs, 
struct vcpu *v)
     if ( (inst_len = svm_get_insn_len(v, INSTR_CLGI)) == 0 )
         return;
 
-    nestedsvm_vcpu_clgi(v);
+    vcpu_nestedsvm(v).ns_gif = 0;
 
     /* After a CLGI no interrupts should come */
     intr = vmcb_get_vintr(vmcb);
-- 
2.53.0