X-Git-Url: https://codewiz.org/gitweb?a=blobdiff_plain;f=kern%2Fproc.c;h=7fe9c70abc555029f5e7ce17044ab8b7713153fe;hb=39108834d9c102712d6c11830ca9b9fb5b098d19;hp=c0a45a7295649a956c9ce2729583cea2a61bf7bd;hpb=277b540c0764dd376dcf583acdc97a2b2fd3d8e6;p=bertos.git diff --git a/kern/proc.c b/kern/proc.c index c0a45a72..7fe9c70a 100755 --- a/kern/proc.c +++ b/kern/proc.c @@ -3,7 +3,7 @@ * * * \brief Simple realtime multitasking scheduler. @@ -17,8 +17,50 @@ /*#* *#* $Log$ - *#* Revision 1.12 2004/08/25 14:12:09 rasky - *#* Aggiornato il comment block dei log RCS + *#* Revision 1.27 2005/11/04 16:20:02 bernie + *#* Fix reference to README.devlib in header. + *#* + *#* Revision 1.26 2005/04/11 19:10:28 bernie + *#* Include top-level headers from cfg/ subdir. + *#* + *#* Revision 1.25 2005/03/15 00:20:54 bernie + *#* proc_schedule(): New sanity check. + *#* + *#* Revision 1.24 2005/01/08 09:20:54 bernie + *#* Remove unused variable. + *#* + *#* Revision 1.23 2004/12/13 12:07:06 bernie + *#* DISABLE_IRQSAVE/ENABLE_IRQRESTORE: Convert to IRQ_SAVE_DISABLE/IRQ_RESTORE. + *#* + *#* Revision 1.22 2004/12/13 11:51:08 bernie + *#* DISABLE_INTS/ENABLE_INTS: Convert to IRQ_DISABLE/IRQ_ENABLE. + *#* + *#* Revision 1.21 2004/11/28 23:20:25 bernie + *#* Remove obsolete INITLIST macro. + *#* + *#* Revision 1.20 2004/11/16 22:37:14 bernie + *#* Replace IPTR with iptr_t. + *#* + *#* Revision 1.19 2004/10/19 11:47:39 bernie + *#* Kill warnings when !CONFIG_PROC_MONITOR. + *#* + *#* Revision 1.18 2004/10/19 08:54:43 bernie + *#* Initialize forbid_cnt; Formatting/comments fixes. + *#* + *#* Revision 1.17 2004/10/19 08:47:13 bernie + *#* proc_rename(), proc_forbid(), proc_permit(): New functions. + *#* + *#* Revision 1.16 2004/10/03 20:39:28 bernie + *#* Import changes from sc/firmware. + *#* + *#* Revision 1.15 2004/09/20 03:29:39 bernie + *#* C++ fixes. + *#* + *#* Revision 1.14 2004/09/14 21:06:44 bernie + *#* Use debug.h instead of kdebug.h. + *#* + *#* Revision 1.13 2004/08/29 21:58:53 bernie + *#* Include macros.h explicityl. *#* *#* Revision 1.11 2004/08/24 16:09:08 bernie *#* Add missing header. @@ -56,21 +98,24 @@ *#* *#*/ -#include "cpu.h" #include "proc_p.h" #include "proc.h" +#include #include "event.h" #include "hw.h" -#include -#include /* ARCH_EMUL */ +#include +#include /* ARCH_EMUL */ +#include /* ABS() */ #include /* memset() */ -/*! CPU dependent context switching routines - * \note This function *MUST* preserve also the status of the interrupts. +/*! + * 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); +EXTERN_C void asm_switch_context(cpustack_t **new_sp, cpustack_t **save_sp); +EXTERN_C int asm_switch_version(void); /* * The scheduer tracks ready and waiting processes @@ -97,109 +142,23 @@ uint16_t Quantum; extern List StackFreeList; #endif -/* The main process (the one that executes main()) */ +/*! The main process (the one that executes main()). */ struct Process MainProcess; -#if CONFIG_KERN_MONITOR -List MonitorProcs; - -static void monitor_init(void) -{ - INITLIST(&MonitorProcs); -} - -static void monitor_add(Process* proc, const char* name, cpustack_t* stack_base, size_t stack_size) -{ - proc->monitor.name = name; - 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; -} - -#if CONFIG_KERN_MONITOR - -void monitor_debug_stacks(void) -{ - struct Process* p; - int i; - - if (ISLISTEMPTY(&MonitorProcs)) - { - kputs("No stacks registered in the monitor\n"); - return; - } - - kprintf("%-24s %-6s%-8s%-8s%-8s\n", "Process name", "TCB", "SPbase", "SPsize", "SPfree"); - for (i=0;i<56;i++) - kputchar('-'); - kputchar('\n'); - - 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("%-24s %04x %04x %4x %4x\n", p->monitor.name, (uint16_t)p, (uint16_t)p->monitor.stack_base, (uint16_t)p->monitor.stack_size, (uint16_t)free); - } -} - -#endif /* CONFIG_KERN_MONITOR */ - -#endif - - -static void proc_init_struct(Process* proc) +static void proc_init_struct(Process *proc) { - /* Avoid warning for unused argument */ + /* Avoid warning for unused argument. */ (void)proc; #if CONFIG_KERN_SIGNALS proc->sig_recv = 0; #endif +#if CONFIG_KERN_PREEMPTIVE + proc->forbid_cnt = 0; +#endif + #if CONFIG_KERN_HEAP proc->flags = 0; #endif @@ -208,7 +167,7 @@ static void proc_init_struct(Process* proc) void proc_init(void) { - INITLIST(&ProcReadyList); + LIST_INIT(&ProcReadyList); #if CONFIG_KERN_MONITOR monitor_init(); @@ -232,10 +191,9 @@ void proc_init(void) * \return Process structure of new created process * if successful, NULL otherwise. */ -struct Process *proc_new_with_name(UNUSED(const char*, name), void (*entry)(void), IPTR data, size_t stacksize, cpustack_t *stack_base) +struct Process *proc_new_with_name(UNUSED(const char*, name), void (*entry)(void), iptr_t data, 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 @@ -243,9 +201,7 @@ struct Process *proc_new_with_name(UNUSED(const char*, name), void (*entry)(void #endif #if (ARCH & ARCH_EMUL) - /* Ignore stack provided by caller - * and use the large enough default instead - */ + /* Ignore stack provided by caller and use the large enough default instead. */ stack_base = (cpustack_t *)StackFreeList.head; REMOVE((Node *)stack_base); stacksize = DEF_STACKSIZE; @@ -309,9 +265,7 @@ struct Process *proc_new_with_name(UNUSED(const char*, name), void (*entry)(void CPU_PUSH_WORD(proc->stack, CPU_REG_INIT_VALUE(i)); /* Add to ready list */ - DISABLE_IRQSAVE(flags); - SCHED_ENQUEUE(proc); - ENABLE_IRQRESTORE(flags); + ATOMIC(SCHED_ENQUEUE(proc)); #if CONFIG_KERN_MONITOR monitor_add(proc, name, stack_base, stacksize); @@ -320,6 +274,16 @@ struct Process *proc_new_with_name(UNUSED(const char*, name), void (*entry)(void return proc; } +/*! Rename a process */ +void proc_rename(struct Process *proc, const char *name) +{ +#if CONFIG_KERN_MONITOR + monitor_rename(proc, name); +#else + (void)proc; (void)name; +#endif +} + /*! * System scheduler: pass CPU control to the next process in @@ -335,15 +299,18 @@ void proc_schedule(void) * the compiler might put them on the stack of the process * being switched out. */ - static Process *old_process; + static struct Process *old_process; static cpuflags_t flags; /* Remember old process to save its context later */ old_process = CurrentProcess; + /* Scheduling in interrupts is a nono. */ + ASSERT(!IRQ_RUNNING()); + /* Poll on the ready queue for the first ready process */ - DISABLE_IRQSAVE(flags); - while (!(CurrentProcess = (struct Process*)REMHEAD(&ProcReadyList))) + IRQ_SAVE_DISABLE(flags); + while (!(CurrentProcess = (struct Process *)REMHEAD(&ProcReadyList))) { /* * Make sure we physically reenable interrupts here, no matter what @@ -351,22 +318,23 @@ void proc_schedule(void) * 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 + * \todo If there was a way to write sig_wait() so that it does not * disable interrupts while waiting, there would not be any * reason to do this. */ - ENABLE_INTS; + IRQ_ENABLE; SCHEDULER_IDLE; - DISABLE_INTS; + IRQ_DISABLE; } - ENABLE_IRQRESTORE(flags); + IRQ_RESTORE(flags); - /* Optimization: don't switch contexts when the active + /* + * Optimization: don't switch contexts when the active * process has not changed. */ if (CurrentProcess != old_process) { - static cpustack_t* dummy; + static cpustack_t *dummy; #if CONFIG_KERN_PREEMPTIVE /* Reset quantum for this process */ @@ -434,9 +402,9 @@ void proc_switch(void) /* Just like proc_schedule, this function must not have auto variables. */ static cpuflags_t flags; - DISABLE_IRQSAVE(flags); + IRQ_SAVE_DISABLE(flags); SCHED_ENQUEUE(CurrentProcess); - ENABLE_IRQRESTORE(flags); + IRQ_RESTORE(flags); proc_schedule(); } @@ -453,13 +421,52 @@ struct Process *proc_current(void) /*! * Get the pointer to the user data of the current process */ -IPTR proc_current_user_data(void) +iptr_t proc_current_user_data(void) { return CurrentProcess->user_data; } + +#if CONFIG_KERN_PREEMPTIVE + +/*! + * Disable preemptive task switching. + * + * The scheduler maintains a per-process nesting counter. Task switching is + * effectively re-enabled only when the number of calls to proc_permit() + * matches the number of calls to proc_forbid(). + * + * Calling functions that could sleep while task switching is disabled + * is dangerous, although supported. Preemptive task switching is + * resumed while the process is sleeping and disabled again as soon as + * it wakes up again. + * + * \sa proc_permit() + */ +void proc_forbid(void) +{ + /* No need to protect against interrupts here. */ + ++CurrentProcess->forbid_cnt; +} + +/*! + * Re-enable preemptive task switching. + * + * \sa proc_forbid() + */ +void proc_permit(void) +{ + /* No need to protect against interrupts here. */ + --CurrentProcess->forbid_cnt; +} + +#endif /* CONFIG_KERN_PREEMPTIVE */ + + #if 0 /* Simple testcase for the scheduler */ +#include + /*! * Proc scheduling test subthread 1 */