Improve efficiency even further. Introduce the configMAX_SYSCALL_INTERRUPT_PRIORITY feature.

git-svn-id: https://freertos.svn.sourceforge.net/svnroot/freertos/trunk@423 1d2547de-c912-0410-9cb9-b8ca96c0e9e2

2 files changed, 38 insertions, 34 deletions

diff --git a/Source/portable/RVDS/ARM_CM3/port.c b/Source/portable/RVDS/ARM_CM3/port.c
index acbc86c8..cf2cff1d 100644
--- a/Source/portable/RVDS/ARM_CM3/port.c
+++ b/Source/portable/RVDS/ARM_CM3/port.c
@@ -76,7 +76,7 @@
 

 /* Each task maintains its own interrupt status in the critical nesting

 variable. */

-unsigned portBASE_TYPE uxCriticalNesting = 0xaaaaaaaa;

+static unsigned portBASE_TYPE uxCriticalNesting = 0xaaaaaaaa;

 

 /* 

  * Setup the timer to generate the tick interrupts.

@@ -111,8 +111,7 @@ portSTACK_TYPE *pxPortInitialiseStack( portSTACK_TYPE *pxTopOfStack, pdTASK_CODE
 	*pxTopOfStack = 0;	/* LR */

 	pxTopOfStack -= 5;	/* R12, R3, R2 and R1. */

 	*pxTopOfStack = ( portSTACK_TYPE ) pvParameters;	/* R0 */

-	pxTopOfStack -= 9;	/* R11, R10, R9, R8, R7, R6, R5 and R4. */

-	*pxTopOfStack = 0x00000000; /* uxCriticalNesting. */

+	pxTopOfStack -= 8;	/* R11, R10, R9, R8, R7, R6, R5 and R4. */

 

 	return pxTopOfStack;

 }

@@ -125,9 +124,7 @@ __asm void vPortSVCHandler( void )
 	ldr	r3, =pxCurrentTCB		/* Restore the context. */

 	ldr r1, [r3]				/* Use pxCurrentTCBConst to get the pxCurrentTCB address. */

 	ldr r0, [r1]				/* The first item in pxCurrentTCB is the task top of stack. */

-	ldmia r0!, {r1, r4-r11}		/* Pop the registers that are not automatically saved on exception entry and the critical nesting count. */

-	ldr r2, =uxCriticalNesting	/* Restore the critical nesting count used by the task. */

-	str r1, [r2]				

+	ldmia r0!, {r4-r11}		/* Pop the registers that are not automatically saved on exception entry and the critical nesting count. */

 	msr psp, r0					/* Restore the task stack pointer. */

 	mov r0, #0

 	msr	basepri, r0

@@ -140,8 +137,14 @@ __asm void vPortStartFirstTask( unsigned long ulValue )
 {

 	PRESERVE8

 

-	msr msp, r0					/* Set the msp back to the start of the stack. */

-	svc 0						/* System call to start first task. */

+	/* Use the NVIC offset register to locate the stack. */

+	ldr r0, =0xE000ED08

+	ldr r0, [r0]

+	ldr r0, [r0]

+	/* Set the msp back to the start of the stack. */

+	msr msp, r0

+	/* Call SVC to start the first task. */

+	svc 0

 }

 /*-----------------------------------------------------------*/

 

@@ -158,6 +161,9 @@ portBASE_TYPE xPortStartScheduler( void )
 	here already. */

 	prvSetupTimerInterrupt();

 	

+	/* Initialise the critical nesting count ready for the first task. */

+	uxCriticalNesting = 0;

+

 	/* Start the first task. */

 	vPortStartFirstTask( *((unsigned portLONG *) 0 ) );

 

@@ -177,10 +183,6 @@ void vPortYieldFromISR( void )
 {

 	/* Set a PendSV to request a context switch. */

 	*(portNVIC_INT_CTRL) |= portNVIC_PENDSVSET;

-

-	/* This function is also called in response to a Yield(), so we want

-	the yield to occur immediately. */

-	portENABLE_INTERRUPTS();

 }

 /*-----------------------------------------------------------*/

 

@@ -211,44 +213,43 @@ __asm void xPortPendSVHandler( void )
 

 	mrs r0, psp						 

 

-	ldr	r3, =pxCurrentTCB		 	/* Get the location of the current TCB. */

+	ldr	r3, =pxCurrentTCB		 	 /* Get the location of the current TCB. */

 	ldr	r2, [r3]						

 

-	ldr r1, =uxCriticalNesting		/* Save the remaining registers and the critical nesting count onto the task stack. */

-	ldr r1, [r1]					

-	stmdb r0!, {r1,r4-r11}			

+	stmdb r0!, {r4-r11}				 /* Save the remaining registers. */

 	str r0, [r2]					 /* Save the new top of stack into the first member of the TCB. */

 

-	stmdb sp!, {r3, r14}			 

-	bl vTaskSwitchContext			

+	stmdb sp!, {r3, r14}		

+	mov r0, #configMAX_SYSCALL_INTERRUPT_PRIORITY

+	msr basepri, r0		 

+	bl vTaskSwitchContext

+	mov r0, #0

+	msr basepri, r0

 	ldmia sp!, {r3, r14}			

 

 	ldr r1, [r3]					 

-	ldr r2, =uxCriticalNesting

 	ldr r0, [r1]					 /* The first item in pxCurrentTCB is the task top of stack. */

-	ldmia r0!, {r1, r4-r11}			 /* Pop the registers and the critical nesting count. */

+	ldmia r0!, {r4-r11}			 /* Pop the registers and the critical nesting count. */

 	str r1, [r2]					 /* Save the new critical nesting value into ulCriticalNesting. */ 

 	msr psp, r0						 

-	orr r14, #0xd					

-

-	cbnz r1, sv_disable_interrupts	 /* If the nesting count is greater than 0 we need to exit with interrupts masked. */

 	bx r14

-

-sv_disable_interrupts

-	mov r1, #configKERNEL_INTERRUPT_PRIORITY

-	msr	basepri, r1					

-	bx r14							

 }

 /*-----------------------------------------------------------*/

 

 void xPortSysTickHandler( void )

 {

+unsigned portLONG ulDummy;

+

 	/* If using preemption, also force a context switch. */

 	#if configUSE_PREEMPTION == 1

 		*(portNVIC_INT_CTRL) |= portNVIC_PENDSVSET;	

 	#endif

 

-	vTaskIncrementTick();

+	ulDummy = portSET_INTERRUPT_MASK_FROM_ISR();

+	{

+		vTaskIncrementTick();

+	}

+	portCLEAR_INTERRUPT_MASK_FROM_ISR();

 }

 /*-----------------------------------------------------------*/

 

@@ -269,7 +270,7 @@ __asm void vPortSetInterruptMask( void )
 	PRESERVE8

 

 	push { r0 }

-	mov r0, #configKERNEL_INTERRUPT_PRIORITY

+	mov r0, #configMAX_SYSCALL_INTERRUPT_PRIORITY

 	msr basepri, r0

 	pop { r0 }

 	bx r14

diff --git a/Source/portable/RVDS/ARM_CM3/portmacro.h b/Source/portable/RVDS/ARM_CM3/portmacro.h
index 2ad85962..f227dbb5 100644
--- a/Source/portable/RVDS/ARM_CM3/portmacro.h
+++ b/Source/portable/RVDS/ARM_CM3/portmacro.h
@@ -106,10 +106,13 @@ extern void vPortClearInterruptMask( void );
 extern void vPortEnterCritical( void );

 extern void vPortExitCritical( void );

 

-#define portDISABLE_INTERRUPTS()	vPortSetInterruptMask()

-#define portENABLE_INTERRUPTS()		vPortClearInterruptMask()

-#define portENTER_CRITICAL()		vPortEnterCritical()

-#define portEXIT_CRITICAL()			vPortExitCritical()

+#define portDISABLE_INTERRUPTS()				vPortSetInterruptMask()

+#define portENABLE_INTERRUPTS()					vPortClearInterruptMask()

+#define portENTER_CRITICAL()					vPortEnterCritical()

+#define portEXIT_CRITICAL()						vPortExitCritical()

+#define portSET_INTERRUPT_MASK_FROM_ISR()		0;vPortSetInterruptMask()

+#define portCLEAR_INTERRUPT_MASK_FROM_ISR(x)	vPortClearInterruptMask()

+

 /*-----------------------------------------------------------*/

 

 /* Task function macros as described on the FreeRTOS.org WEB site. */