[PATCH 4/5] x86/viridian: switch synic to use the new EOI callback

[Roger Pau Monne <roger.pau@xxxxxxxxxx>]

Switch synic interrupts to use an EOI callback in order to execute the
logic tied to the end of interrupt. This allows to remove the synic
call in vlapic_handle_EOI.

Move and rename viridian_synic_ack_sint now that it can be made
static.

Signed-off-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
---
I'm unsure about the logic in viridian_synic_deliver_timer_msg, as it
seems to only set the vector in msg_pending when the message is
already pending?
---
 xen/arch/x86/hvm/viridian/synic.c  | 28 +++++++++++++++-------------
 xen/arch/x86/hvm/vlapic.c          |  4 ----
 xen/include/asm-x86/hvm/viridian.h |  1 -
 3 files changed, 15 insertions(+), 18 deletions(-)

diff --git a/xen/arch/x86/hvm/viridian/synic.c 
b/xen/arch/x86/hvm/viridian/synic.c
index 94a2b88733..250f0353cf 100644
--- a/xen/arch/x86/hvm/viridian/synic.c
+++ b/xen/arch/x86/hvm/viridian/synic.c
@@ -315,6 +315,19 @@ void viridian_synic_poll(struct vcpu *v)
     viridian_time_poll_timers(v);
 }
 
+static void synic_ack_sint(struct vcpu *v, unsigned int vector, void *data)
+{
+    struct viridian_vcpu *vv = v->arch.hvm.viridian;
+    unsigned int sintx = vv->vector_to_sintx[vector];
+
+    ASSERT(v == current);
+
+    if ( sintx < ARRAY_SIZE(vv->sint) )
+        __clear_bit(array_index_nospec(sintx, ARRAY_SIZE(vv->sint)),
+                    &vv->msg_pending);
+}
+
+
 bool viridian_synic_deliver_timer_msg(struct vcpu *v, unsigned int sintx,
                                       unsigned int index,
                                       uint64_t expiration,
@@ -361,7 +374,8 @@ bool viridian_synic_deliver_timer_msg(struct vcpu *v, 
unsigned int sintx,
     memcpy(msg->u.payload, &payload, sizeof(payload));
 
     if ( !vs->masked )
-        vlapic_set_irq(vcpu_vlapic(v), vs->vector, 0);
+        vlapic_set_irq_callback(vcpu_vlapic(v), vs->vector, 0,
+                                synic_ack_sint, NULL);
 
     return true;
 }
@@ -380,18 +394,6 @@ bool viridian_synic_is_auto_eoi_sint(const struct vcpu *v,
     return vs->auto_eoi;
 }
 
-void viridian_synic_ack_sint(const struct vcpu *v, unsigned int vector)
-{
-    struct viridian_vcpu *vv = v->arch.hvm.viridian;
-    unsigned int sintx = vv->vector_to_sintx[vector];
-
-    ASSERT(v == current);
-
-    if ( sintx < ARRAY_SIZE(vv->sint) )
-        __clear_bit(array_index_nospec(sintx, ARRAY_SIZE(vv->sint)),
-                    &vv->msg_pending);
-}
-
 void viridian_synic_save_vcpu_ctxt(const struct vcpu *v,
                                    struct hvm_viridian_vcpu_context *ctxt)
 {
diff --git a/xen/arch/x86/hvm/vlapic.c b/xen/arch/x86/hvm/vlapic.c
index 3b3b3d7621..701ff942e6 100644
--- a/xen/arch/x86/hvm/vlapic.c
+++ b/xen/arch/x86/hvm/vlapic.c
@@ -489,12 +489,8 @@ void vlapic_handle_EOI(struct vlapic *vlapic, u8 vector)
     void *data;
     unsigned long flags;
 
-    /* All synic SINTx vectors are edge triggered */
-
     if ( vlapic_test_vector(vector, &vlapic->regs->data[APIC_TMR]) )
         vioapic_update_EOI(d, vector);
-    else if ( has_viridian_synic(d) )
-        viridian_synic_ack_sint(v, vector);
 
     spin_lock_irqsave(&vlapic->callback_lock, flags);
     callback = vlapic->callbacks[vector].callback;
diff --git a/xen/include/asm-x86/hvm/viridian.h 
b/xen/include/asm-x86/hvm/viridian.h
index 844e56b38f..d387d11ce0 100644
--- a/xen/include/asm-x86/hvm/viridian.h
+++ b/xen/include/asm-x86/hvm/viridian.h
@@ -89,7 +89,6 @@ void viridian_apic_assist_clear(const struct vcpu *v);
 void viridian_synic_poll(struct vcpu *v);
 bool viridian_synic_is_auto_eoi_sint(const struct vcpu *v,
                                      unsigned int vector);
-void viridian_synic_ack_sint(const struct vcpu *v, unsigned int vector);
 
 #endif /* __ASM_X86_HVM_VIRIDIAN_H__ */
 
-- 
2.28.0