diff --git a/portable/GCC/ARM_CM0/portmacro.h b/portable/GCC/ARM_CM0/portmacro.h
index db69cfddf..b9e9ef662 100644
--- a/portable/GCC/ARM_CM0/portmacro.h
+++ b/portable/GCC/ARM_CM0/portmacro.h
@@ -30,9 +30,11 @@
 #ifndef PORTMACRO_H
 #define PORTMACRO_H
 
+/* *INDENT-OFF* */
 #ifdef __cplusplus
-extern "C" {
+    extern "C" {
 #endif
+/* *INDENT-ON* */
 
 /*-----------------------------------------------------------
  * Port specific definitions.
@@ -123,8 +125,42 @@ extern void vClearInterruptMaskFromISR( uint32_t ulMask )  __attribute__( ( nake
 
 #define portMEMORY_BARRIER()    __asm volatile ( "" ::: "memory" )
 
-#ifdef __cplusplus
+
+#define portINLINE              __inline
+
+#ifndef portFORCE_INLINE
+    #define portFORCE_INLINE    inline __attribute__( ( always_inline ) )
+#endif
+
+/*-----------------------------------------------------------*/
+
+portFORCE_INLINE static BaseType_t xPortIsInsideInterrupt( void )
+{
+    uint32_t ulCurrentInterrupt;
+    BaseType_t xReturn;
+
+    /* Obtain the number of the currently executing interrupt. */
+    __asm volatile ( "mrs %0, ipsr" : "=r" ( ulCurrentInterrupt )::"memory" );
+
+    if( ulCurrentInterrupt == 0 )
+    {
+        xReturn = pdFALSE;
+    }
+    else
+    {
+        xReturn = pdTRUE;
+    }
+
+    return xReturn;
 }
+
+/*-----------------------------------------------------------*/
+
+
+/* *INDENT-OFF* */
+#ifdef __cplusplus
+    }
 #endif
+/* *INDENT-ON* */
 
 #endif /* PORTMACRO_H */
diff --git a/portable/IAR/ARM_CM0/portmacro.h b/portable/IAR/ARM_CM0/portmacro.h
index 622b584c0..5dcc949b2 100644
--- a/portable/IAR/ARM_CM0/portmacro.h
+++ b/portable/IAR/ARM_CM0/portmacro.h
@@ -26,12 +26,15 @@
  *
  */
 
+
 #ifndef PORTMACRO_H
 #define PORTMACRO_H
 
+/* *INDENT-OFF* */
 #ifdef __cplusplus
-extern "C" {
+    extern "C" {
 #endif
+/* *INDENT-ON* */
 
 /*-----------------------------------------------------------
  * Port specific definitions.
@@ -118,13 +121,45 @@ extern void vClearInterruptMaskFromISR( uint32_t ulMask );
 
 #define portNOP()
 
+#define portINLINE              __inline
+
+#ifndef portFORCE_INLINE
+    #define portFORCE_INLINE    inline __attribute__( ( always_inline ) )
+#endif
+
+/*-----------------------------------------------------------*/
+
+portFORCE_INLINE static BaseType_t xPortIsInsideInterrupt( void )
+{
+    uint32_t ulCurrentInterrupt;
+    BaseType_t xReturn;
+
+    /* Obtain the number of the currently executing interrupt. */
+    __asm volatile ( "mrs %0, ipsr" : "=r" ( ulCurrentInterrupt )::"memory" );
+
+    if( ulCurrentInterrupt == 0 )
+    {
+        xReturn = pdFALSE;
+    }
+    else
+    {
+        xReturn = pdTRUE;
+    }
+
+    return xReturn;
+}
+
+/*-----------------------------------------------------------*/
+
 /* Suppress warnings that are generated by the IAR tools, but cannot be fixed in
  * the source code because to do so would cause other compilers to generate
  * warnings. */
 #pragma diag_suppress=Pa082
 
+/* *INDENT-OFF* */
 #ifdef __cplusplus
-}
+    }
 #endif
+/* *INDENT-ON* */
 
 #endif /* PORTMACRO_H */
diff --git a/portable/RVDS/ARM_CM0/portmacro.h b/portable/RVDS/ARM_CM0/portmacro.h
index fb1eea7ca..4a1ea8a7b 100644
--- a/portable/RVDS/ARM_CM0/portmacro.h
+++ b/portable/RVDS/ARM_CM0/portmacro.h
@@ -120,6 +120,41 @@ extern void vClearInterruptMaskFromISR( uint32_t ulMask );
 
 #define portNOP()
 
+#define portINLINE              __inline
+
+#ifndef portFORCE_INLINE
+    #define portFORCE_INLINE    __forceinline
+#endif
+
+/*-----------------------------------------------------------*/
+
+static portFORCE_INLINE BaseType_t xPortIsInsideInterrupt( void )
+{
+    uint32_t ulCurrentInterrupt;
+    BaseType_t xReturn;
+
+    /* Obtain the number of the currently executing interrupt. */
+    __asm
+    {
+/* *INDENT-OFF* */
+            mrs ulCurrentInterrupt, ipsr
+/* *INDENT-ON* */
+    }
+
+    if( ulCurrentInterrupt == 0 )
+    {
+        xReturn = pdFALSE;
+    }
+    else
+    {
+        xReturn = pdTRUE;
+    }
+
+    return xReturn;
+}
+
+/*-----------------------------------------------------------*/
+
 /* *INDENT-OFF* */
 #ifdef __cplusplus
     }