Changeset 106541 in vbox for trunk/src/VBox/Devices/Serial

Timestamp:

Oct 21, 2024 7:31:54 AM (6 weeks ago)

Author:

vboxsync

Message:

Devices/Serial/DevPL011: Small optimization, only update the IRQ state if it actually changes, bugref:10403

File:

• trunk/src/VBox/Devices/Serial/DevPL011.cpp (modified) (2 diffs)

trunk/src/VBox/Devices/Serial/DevPL011.cpp

@@ -382 +382 @@
     /** The receive FIFO. */
     PL011FIFO                       FifoRecv;
+    /** The current state of the IRQ line. */
+    bool                            fIrqAsserted;
 } DEVPL011;
 /** Pointer to the shared serial device state. */
@@ -489 +491 @@
                  pThis, pThis->uRegIrqSts, pThis->uRegIrqMask));
 
+    /* Only set the IRQ state if it actually changed. */
+    bool fAssert = RT_BOOL(pThis->uRegIrqSts & ~pThis->uRegIrqMask);
     RT_NOREF(pThisCC);
-    if (pThis->uRegIrqSts & ~pThis->uRegIrqMask)
-        PDMDevHlpISASetIrqNoWait(pDevIns, pThis->u16Irq, 1);
-    else
-        PDMDevHlpISASetIrqNoWait(pDevIns, pThis->u16Irq, 0);
+    if (pThis->fIrqAsserted ^ fAssert)
+    {
+        PDMDevHlpISASetIrqNoWait(pDevIns, pThis->u16Irq, fAssert);
+        pThis->fIrqAsserted = fAssert;
+    }
 }