Improve efficiency even further. Introduce the configMAX_SYSCALL_INTERRUPT_PRIORITY feature.

pull/4/head
Richard Barry 17 years ago
parent 3ab4d1f87f
commit 32592e1385

@ -83,7 +83,7 @@ const unsigned portLONG ulKernelPriority = configKERNEL_INTERRUPT_PRIORITY;
/* 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.
@ -118,8 +118,7 @@ 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;
}
@ -131,9 +130,7 @@ void vPortSVCHandler( void )
" ldr r3, pxCurrentTCBConst2 \n" /* Restore the context. */
" ldr r1, [r3] \n" /* Use pxCurrentTCBConst to get the pxCurrentTCB address. */
" ldr r0, [r1] \n" /* The first item in pxCurrentTCB is the task top of stack. */
" ldmia r0!, {r1, r4-r11} \n" /* Pop the registers that are not automatically saved on exception entry and the critical nesting count. */
" ldr r2, uxCriticalNestingConst2 \n" /* Restore the critical nesting count used by the task. */
" str r1, [r2] \n"
" ldmia r0!, {r4-r11} \n" /* Pop the registers that are not automatically saved on exception entry and the critical nesting count. */
" msr psp, r0 \n" /* Restore the task stack pointer. */
" mov r0, #0 \n"
" msr basepri, r0 \n"
@ -142,7 +139,6 @@ void vPortSVCHandler( void )
" \n"
" .align 2 \n"
"pxCurrentTCBConst2: .word pxCurrentTCB \n"
"uxCriticalNestingConst2: .word uxCriticalNesting \n"
);
}
/*-----------------------------------------------------------*/
@ -154,6 +150,9 @@ void vPortStartFirstTask( unsigned long ulValue )
( void ) ulValue;
asm volatile(
" ldr r0, =0xE000ED08 \n" /* Use the NVIC offset register to locate the stack. */
" ldr r0, [r0] \n"
" ldr r0, [r0] \n"
" msr msp, r0 \n" /* Set the msp back to the start of the stack. */
" svc 0 \n" /* System call to start first task. */
);
@ -173,6 +172,9 @@ 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 ) );
@ -192,10 +194,6 @@ 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();
}
/*-----------------------------------------------------------*/
@ -227,35 +225,26 @@ void xPortPendSVHandler( void )
" ldr r3, pxCurrentTCBConst \n" /* Get the location of the current TCB. */
" ldr r2, [r3] \n"
" \n"
" ldr r1, uxCriticalNestingConst \n" /* Save the remaining registers and the critical nesting count onto the task stack. */
" ldr r1, [r1] \n"
" stmdb r0!, {r1,r4-r11} \n"
" stmdb r0!, {r4-r11} \n" /* Save the remaining registers. */
" str r0, [r2] \n" /* Save the new top of stack into the first member of the TCB. */
" \n"
" stmdb sp!, {r3, r14} \n"
" mov r0, %0 \n"
" msr basepri, r0 \n"
" bl vTaskSwitchContext \n"
" mov r0, #0 \n"
" msr basepri, r0 \n"
" ldmia sp!, {r3, r14} \n"
" \n" /* Restore the context, including the critical nesting count. */
" ldr r1, [r3] \n"
" ldr r2, uxCriticalNestingConst \n"
" ldr r0, [r1] \n" /* The first item in pxCurrentTCB is the task top of stack. */
" ldmia r0!, {r1, r4-r11} \n" /* Pop the registers and the critical nesting count. */
" str r1, [r2] \n" /* Save the new critical nesting value into ulCriticalNesting. */
" ldmia r0!, {r4-r11} \n" /* Pop the registers. */
" msr psp, r0 \n"
" orr r14, #0xd \n"
" \n" /* Exit with interrupts in the state required by the task. */
" cbnz r1, sv_disable_interrupts \n" /* If the nesting count is greater than 0 we need to exit with interrupts masked. */
" bx r14 \n"
" \n"
"sv_disable_interrupts: \n"
" ldr r1, =ulKernelPriority \n"
" ldr r1, [r1] \n"
" msr basepri, r1 \n"
" bx r14 \n"
" \n"
" .align 2 \n"
"pxCurrentTCBConst: .word pxCurrentTCB \n"
"uxCriticalNestingConst: .word uxCriticalNesting \n"
::"i"(configMAX_SYSCALL_INTERRUPT_PRIORITY)
);
}
/*-----------------------------------------------------------*/
@ -267,7 +256,11 @@ void xPortSysTickHandler( void )
*(portNVIC_INT_CTRL) |= portNVIC_PENDSVSET;
#endif
portSET_INTERRUPT_MASK_FROM_ISR();
{
vTaskIncrementTick();
}
portCLEAR_INTERRUPT_MASK_FROM_ISR();
}
/*-----------------------------------------------------------*/

@ -101,35 +101,39 @@ extern void vPortYieldFromISR( void );
/* Critical section management. */
#define vPortSetInterruptMask() \
/*
* Set basepri to portMAX_SYSCALL_INTERRUPT_PRIORITY without effecting other
* registers. r0 is clobbered.
*/
#define portSET_INTERRUPT_MASK() \
__asm volatile \
( \
" push { r0 } \n" \
" ldr r0, =ulKernelPriority \n" \
" ldr r0, [r0] \n" \
" mov r0, %0 \n" \
" msr basepri, r0 \n" \
" pop { r0 } " \
::"i"(configMAX_SYSCALL_INTERRUPT_PRIORITY):"r0" \
)
/*-----------------------------------------------------------*/
#define vPortClearInterruptMask() \
/*
* Set basepri back to 0 without effective other registers.
* r0 is clobbered.
*/
#define portCLEAR_INTERRUPT_MASK() \
__asm volatile \
( \
" push { r0 } \n" \
" mov r0, #0 \n" \
" msr basepri, r0 \n" \
" pop { r0 } " \
:::"r0" \
)
/*-----------------------------------------------------------*/
#define portSET_INTERRUPT_MASK_FROM_ISR() 0;portSET_INTERRUPT_MASK()
#define portCLEAR_INTERRUPT_MASK_FROM_ISR(x) portCLEAR_INTERRUPT_MASK()
extern void vPortEnterCritical( void );
extern void vPortExitCritical( void );
#define portDISABLE_INTERRUPTS() vPortSetInterruptMask();
#define portENABLE_INTERRUPTS() vPortClearInterruptMask();
#define portDISABLE_INTERRUPTS() portSET_INTERRUPT_MASK()
#define portENABLE_INTERRUPTS() portCLEAR_INTERRUPT_MASK()
#define portENTER_CRITICAL() vPortEnterCritical()
#define portEXIT_CRITICAL() vPortExitCritical()
/*-----------------------------------------------------------*/

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