From 234d16704c3e18d531637c5af783dd1c2b23d12b Mon Sep 17 00:00:00 2001 From: Gregory Nutt Date: Thu, 28 Aug 2014 07:16:14 -0600 Subject: MIPS: Move address environment switch from the task switchers to the interrupt handler. That may save doing the action multiple times per interrupt --- nuttx/arch/mips/src/mips32/up_blocktask.c | 14 ++---- nuttx/arch/mips/src/mips32/up_doirq.c | 57 +++++++++++++++++-------- nuttx/arch/mips/src/mips32/up_unblocktask.c | 14 ++---- nuttx/arch/mips/src/pic32mx/pic32mx-decodeirq.c | 46 ++++++++++++++++---- 4 files changed, 82 insertions(+), 49 deletions(-) diff --git a/nuttx/arch/mips/src/mips32/up_blocktask.c b/nuttx/arch/mips/src/mips32/up_blocktask.c index e6979625a..69304c522 100644 --- a/nuttx/arch/mips/src/mips32/up_blocktask.c +++ b/nuttx/arch/mips/src/mips32/up_blocktask.c @@ -138,19 +138,11 @@ void up_block_task(struct tcb_s *tcb, tstate_t task_state) rtcb = (struct tcb_s*)g_readytorun.head; - /* Then switch contexts */ + /* Then switch contexts. Any necessary address environment + * changes will be made when the interrupt returns. + */ up_restorestate(rtcb->xcp.regs); - -#ifdef CONFIG_ARCH_ADDRENV - /* Make sure that the address environment for the previously - * running task is closed down gracefully (data caches dump, - * MMU flushed) and set up the address environment for the new - * thread at the head of the ready-to-run list. - */ - - (void)group_addrenv(rtcb); -#endif } /* No, then we will need to perform the user context switch */ diff --git a/nuttx/arch/mips/src/mips32/up_doirq.c b/nuttx/arch/mips/src/mips32/up_doirq.c index 826642caf..6abba7d75 100644 --- a/nuttx/arch/mips/src/mips32/up_doirq.c +++ b/nuttx/arch/mips/src/mips32/up_doirq.c @@ -1,7 +1,7 @@ /**************************************************************************** * arch/mips/src/mips32/up_doirq.c * - * Copyright (C) 2011 Gregory Nutt. All rights reserved. + * Copyright (C) 2011, 2014 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Redistribution and use in source and binary forms, with or without @@ -49,6 +49,8 @@ #include "up_arch.h" #include "up_internal.h" +#include "group/group.h" + /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ @@ -75,25 +77,17 @@ uint32_t *up_doirq(int irq, uint32_t *regs) #ifdef CONFIG_SUPPRESS_INTERRUPTS PANIC(); #else - uint32_t *savestate; - - /* Nested interrupts are not supported in this implementation. If you want - * to implement nested interrupts, you would have to (1) change the way that - * current_regs is handled and (2) the design associated with - * CONFIG_ARCH_INTERRUPTSTACK. The savestate variable will not work for - * that purpose as implemented here because only the outermost nested - * interrupt can result in a context switch (it can probably be deleted). - */ - /* Current regs non-zero indicates that we are processing an interrupt; * current_regs is also used to manage interrupt level context switches. + * + * Nested interrupts are not supported */ - savestate = (uint32_t*)current_regs; + DEBUGASSERT(current_regs == NULL); current_regs = regs; - /* Disable further occurences of this interrupt (until the interrupt sources - * have been clear by the driver. + /* Disable further occurrences of this interrupt (until the interrupt sources + * have been clear by the driver). */ up_disable_irq(irq); @@ -102,6 +96,34 @@ uint32_t *up_doirq(int irq, uint32_t *regs) irq_dispatch(irq, regs); +#if defined(CONFIG_ARCH_FPU) || defined(CONFIG_ARCH_ADDRENV) + /* Check for a context switch. If a context switch occurred, then + * current_regs will have a different value than it did on entry. If an + * interrupt level context switch has occurred, then restore the floating + * point state and the establish the correct address environment before + * returning from the interrupt. + */ + + if (regs != current_regs) + { +#ifdef CONFIG_ARCH_FPU + /* Restore floating point registers */ + + up_restorefpu((uint32_t*)current_regs); +#endif + +#ifdef CONFIG_ARCH_ADDRENV + /* Make sure that the address environment for the previously + * running task is closed down gracefully (data caches dump, + * MMU flushed) and set up the address environment for the new + * thread at the head of the ready-to-run list. + */ + + (void)group_addrenv(rtcb); +#endif + } +#endif + /* If a context switch occurred while processing the interrupt then * current_regs may have change value. If we return any value different * from the input regs, then the lower level will know that a context @@ -110,12 +132,11 @@ uint32_t *up_doirq(int irq, uint32_t *regs) regs = (uint32_t*)current_regs; - /* Restore the previous value of current_regs. NULL would indicate that - * we are no longer in an interrupt handler. It will be non-NULL if we - * are returning from a nested interrupt. + /* Set current_regs to NULL to indicate that we are no longer in an + * interrupt handler. */ - current_regs = savestate; + current_regs = NULL; /* Unmask the last interrupt (global interrupts are still disabled) */ diff --git a/nuttx/arch/mips/src/mips32/up_unblocktask.c b/nuttx/arch/mips/src/mips32/up_unblocktask.c index 522c61133..c68a62fd7 100644 --- a/nuttx/arch/mips/src/mips32/up_unblocktask.c +++ b/nuttx/arch/mips/src/mips32/up_unblocktask.c @@ -129,19 +129,11 @@ void up_unblock_task(struct tcb_s *tcb) rtcb = (struct tcb_s*)g_readytorun.head; - /* Then switch contexts */ + /* Then switch contexts. Any necessary address environment + * changes will be made when the interrupt returns. + */ up_restorestate(rtcb->xcp.regs); - -#ifdef CONFIG_ARCH_ADDRENV - /* Make sure that the address environment for the previously - * running task is closed down gracefully (data caches dump, - * MMU flushed) and set up the address environment for the new - * thread at the head of the ready-to-run list. - */ - - (void)group_addrenv(rtcb); -#endif } /* No, then we will need to perform the user context switch */ diff --git a/nuttx/arch/mips/src/pic32mx/pic32mx-decodeirq.c b/nuttx/arch/mips/src/pic32mx/pic32mx-decodeirq.c index 9facbf310..650e6851c 100644 --- a/nuttx/arch/mips/src/pic32mx/pic32mx-decodeirq.c +++ b/nuttx/arch/mips/src/pic32mx/pic32mx-decodeirq.c @@ -1,7 +1,7 @@ /**************************************************************************** * arch/mips/src/pic32mx/pic32mx-decodeirq.c * - * Copyright (C) 2011 Gregory Nutt. All rights reserved. + * Copyright (C) 2011, 2014 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Redistribution and use in source and binary forms, with or without @@ -53,6 +53,8 @@ #include "pic32mx-int.h" #include "pic32mx-internal.h" +#include "group/group.h" + /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ @@ -77,7 +79,7 @@ * Name: pic32mx_decodeirq * * Description: - * Called from assembly language logic when an interrrupt exception occurs. + * Called from assembly language logic when an interrupt exception occurs. * This function decodes and dispatches the interrupt. * ****************************************************************************/ @@ -145,16 +147,42 @@ uint32_t *pic32mx_decodeirq(uint32_t *regs) regs = (uint32_t*)current_regs; - /* Restore the previous value of current_regs. NULL would indicate that - * we are no longer in an interrupt handler. It will be non-NULL if we - * are returning from a nested interrupt. +#if defined(CONFIG_ARCH_FPU) || defined(CONFIG_ARCH_ADDRENV) + /* Check for a context switch. If a context switch occurred, then + * current_regs will have a different value than it did on entry. If an + * interrupt level context switch has occurred, then restore the floating + * point state and the establish the correct address environment before + * returning from the interrupt. */ + if (regs != current_regs) + { +#ifdef CONFIG_ARCH_FPU + /* Restore floating point registers */ + + up_restorefpu((uint32_t*)current_regs); +#endif + +#ifdef CONFIG_ARCH_ADDRENV + /* Make sure that the address environment for the previously + * running task is closed down gracefully (data caches dump, + * MMU flushed) and set up the address environment for the new + * thread at the head of the ready-to-run list. + */ + + (void)group_addrenv(rtcb); +#endif + } +#endif + #ifdef CONFIG_PIC32MX_NESTED_INTERRUPTS - /* I think there are some task switching issues here. You should not - * enable nested interrupts unless you are ready to deal with the - * complexities of nested context switching. The logic here is probably - * insufficient. + /* Restore the previous value of current_regs. NULL would indicate that + * we are no longer in an interrupt handler. It will be non-NULL if we + * are returning from a nested interrupt. + * + * REVISIT: There are task switching issues! You should not enable + * nested interrupts unless you are ready to deal with the complexities + * of fixing nested context switching. The logic here is insufficient. */ current_regs = savestate; -- cgit v1.2.3