X-Git-Url: https://codewiz.org/gitweb?a=blobdiff_plain;f=kern%2Fproc.c;h=6ce3071aaf104379519f69e74ec7f799ac1c5424;hb=de2caf08ef2eca066c3d5a40ab91d7f34c3f555e;hp=a11e4985774ce4c05d1763972a50564082ec411a;hpb=1cc167e20f21d2e81527ca47ccd4a21a6198f86f;p=bertos.git diff --git a/kern/proc.c b/kern/proc.c index a11e4985..6ce3071a 100755 --- a/kern/proc.c +++ b/kern/proc.c @@ -1,9 +1,9 @@ -/** +/*! * \file * * * \brief Simple realtime multitasking scheduler. @@ -17,6 +17,25 @@ /* * $Log$ + * Revision 1.7 2004/08/02 20:20:29 aleph + * Merge from project_ks + * + * Revision 1.6 2004/07/30 14:24:16 rasky + * Task switching con salvataggio perfetto stato di interrupt (SR) + * Kernel monitor per dump informazioni su stack dei processi + * + * Revision 1.5 2004/07/14 14:18:09 rasky + * Merge da SC: Rimosso timer dentro il task, che è uno spreco di memoria per troppi task + * + * Revision 1.4 2004/07/13 19:21:28 aleph + * Avoid warning for unused arg when compiled without some CONFIG_KERN_xx options + * + * Revision 1.3 2004/06/06 18:37:57 bernie + * Rename event macros to look like regular functions. + * + * Revision 1.2 2004/06/03 11:27:09 bernie + * Add dual-license information. + * * Revision 1.1 2004/05/23 17:27:00 bernie * Import kern/ subdirectory. * @@ -31,8 +50,11 @@ #include /* memset() */ -/* CPU dependent context switching routines */ +/*! CPU dependent context switching routines + * \note This function *MUST* preserve also the status of the interrupts. + */ extern void asm_switch_context(cpustack_t **new_sp, cpustack_t **save_sp); +extern int asm_switch_version(void); /* * The scheduer tracks ready and waiting processes @@ -44,6 +66,7 @@ extern void asm_switch_context(cpustack_t **new_sp, cpustack_t **save_sp); REGISTER Process *CurrentProcess; REGISTER List ProcReadyList; + #if CONFIG_KERN_PREEMPTIVE /* * The time sharing scheduler forces a task switch when @@ -61,12 +84,85 @@ extern List StackFreeList; /* The main process (the one that executes main()) */ struct Process MainProcess; -static void proc_init_struct(Process* proc) + +#if CONFIG_KERN_MONITOR +List MonitorProcs; + +static void monitor_init(void) +{ + INITLIST(&MonitorProcs); +} + +static void monitor_add(Process* proc, cpustack_t* stack_base, size_t stack_size) { -#if CONFIG_KERN_TIMER - INITEVENT_SIG(&proc->proc_timer.expire, proc, SIG_SINGLE); + proc->monitor.stack_base = stack_base; + proc->monitor.stack_size = stack_size; + + ADDTAIL(&MonitorProcs, &proc->monitor.link); +} + +static void monitor_remove(Process* proc) +{ + REMOVE(&proc->monitor.link); +} + +#define MONITOR_NODE_TO_PROCESS(node) \ + (struct Process*)((char*)(node) - offsetof(struct Process, monitor.link)) + +size_t monitor_check_stack(cpustack_t* stack_base, size_t stack_size) +{ + cpustack_t* beg; + cpustack_t* cur; + cpustack_t* end; + size_t sp_free; + + beg = stack_base; + end = stack_base + stack_size / sizeof(cpustack_t) - 1; + + if (CPU_STACK_GROWS_UPWARD) + { + cur = beg; + beg = end; + end = cur; + } + + cur = beg; + while (cur != end) + { + if (*cur != CONFIG_KERN_STACKFILLCODE) + break; + + if (CPU_STACK_GROWS_UPWARD) + cur--; + else + cur++; + } + + sp_free = ABS(cur - beg) * sizeof(cpustack_t); + return sp_free; +} + +void monitor_debug_stacks(void) +{ + struct Process* p; + + for (p = MONITOR_NODE_TO_PROCESS(MonitorProcs.head); + p->monitor.link.succ; + p = MONITOR_NODE_TO_PROCESS(p->monitor.link.succ)) + { + size_t free = monitor_check_stack(p->monitor.stack_base, p->monitor.stack_size); + kprintf("TCB: %x sp_base: %x sp_size: %x sp_free: %x\n", (uint16_t)p, (uint16_t)p->monitor.stack_base, (uint16_t)p->monitor.stack_size, (uint16_t)free); + } +} + #endif + +static void proc_init_struct(Process* proc) +{ + /* Avoid warning for unused argument */ + (void)proc; + #if CONFIG_KERN_SIGNALS proc->sig_recv = 0; #endif @@ -76,15 +172,24 @@ static void proc_init_struct(Process* proc) #endif } + void proc_init(void) { INITLIST(&ProcReadyList); +#if CONFIG_KERN_MONITOR + monitor_init(); +#endif + /* We "promote" the current context into a real process. The only thing we have - to do is create a PCB and make it current. We don't need to setup the stack - pointer because it will be written the first time we switch to another process. */ + * to do is create a PCB and make it current. We don't need to setup the stack + * pointer because it will be written the first time we switch to another process. + */ proc_init_struct(&MainProcess); CurrentProcess = &MainProcess; + + /* Make sure the assembly routine is up-to-date with us */ + ASSERT(asm_switch_version() == 1); } @@ -97,6 +202,7 @@ void proc_init(void) Process *proc_new(void (*entry)(void), size_t stacksize, cpustack_t *stack_base) { Process *proc; + cpuflags_t flags; size_t i; size_t proc_size_words = ROUND2(sizeof(Process), sizeof(cpustack_t)) / sizeof(cpustack_t); #if CONFIG_KERN_HEAP @@ -130,10 +236,10 @@ Process *proc_new(void (*entry)(void), size_t stacksize, cpustack_t *stack_base) ASSERT(stacksize); #endif -#ifdef _DEBUG +#if CONFIG_KERN_MONITOR /* Fill-in the stack with a special marker to help debugging */ memset(stack_base, CONFIG_KERN_STACKFILLCODE, stacksize / sizeof(cpustack_t)); -#endif /* _DEBUG */ +#endif /* Initialize the process control block */ if (CPU_STACK_GROWS_UPWARD) @@ -169,9 +275,13 @@ Process *proc_new(void (*entry)(void), size_t stacksize, cpustack_t *stack_base) CPU_PUSH_WORD(proc->stack, CPU_REG_INIT_VALUE(i)); /* Add to ready list */ - DISABLE_INTS; + DISABLE_IRQSAVE(flags); SCHED_ENQUEUE(proc); - ENABLE_INTS; + ENABLE_IRQRESTORE(flags); + +#if CONFIG_KERN_MONITOR + monitor_add(proc, stack_base, stacksize); +#endif return proc; } @@ -192,29 +302,30 @@ void proc_schedule(void) * being switched out. */ static Process *old_process; + static cpuflags_t flags; /* Remember old process to save its context later */ old_process = CurrentProcess; - CurrentProcess = NULL; - /* Poll on the ready queue for the first ready process - */ - for(;;) /* forever */ + /* Poll on the ready queue for the first ready process */ + DISABLE_IRQSAVE(flags); + while (!(CurrentProcess = (struct Process*)REMHEAD(&ProcReadyList))) { - /* Do CPU specific idle processing (ARGH, should be moved to the end of the loop!) */ + /* + * Make sure we physically reenable interrupts here, no matter what + * the current task status is. This is important because if we + * are idle-spinning, we must allow interrupts, otherwise no + * process will ever wake up. + * + * \todo If there was a way to code sig_wait so that it does not + * disable interrupts while waiting, there would not be any + * reason to do this. + */ + ENABLE_INTS; SCHEDULER_IDLE; - DISABLE_INTS; - if (!ISLISTEMPTY(&ProcReadyList)) - { - /* Get process from ready list */ - CurrentProcess = (Process *)ProcReadyList.head; - REMOVE((Node *)CurrentProcess); - ENABLE_INTS; - break; - } - ENABLE_INTS; } + ENABLE_IRQRESTORE(flags); /* Optimization: don't switch contexts when the active * process has not changed. @@ -271,6 +382,10 @@ void proc_exit(void) */ #endif /* ARCH_EMUL */ +#if CONFIG_KERN_MONITOR + monitor_remove(CurrentProcess); +#endif + CurrentProcess = NULL; proc_schedule(); /* not reached */ @@ -282,9 +397,13 @@ void proc_exit(void) */ void proc_switch(void) { - DISABLE_INTS; + /* Just like proc_schedule, this function must not have auto variables. */ + static cpuflags_t flags; + + DISABLE_IRQSAVE(flags); SCHED_ENQUEUE(CurrentProcess); - ENABLE_INTS; + ENABLE_IRQRESTORE(flags); + proc_schedule(); }