boolean_t
swtch_pri(
__unused struct swtch_pri_args *args)
{
register processor_t myprocessor;
boolean_t result;
disable_preemption();
myprocessor = current_processor();
if (SCHED(processor_queue_empty)(myprocessor) && rt_runq.count == 0) {
mp_enable_preemption();
return (FALSE);
}
enable_preemption();
counter(c_swtch_pri_block++);
thread_depress_abstime(thread_depress_time);
thread_block_reason((thread_continue_t)swtch_pri_continue, NULL, AST_YIELD);
thread_depress_abort_internal(current_thread());
disable_preemption();
myprocessor = current_processor();
result = !SCHED(processor_queue_empty)(myprocessor) || rt_runq.count > 0;
enable_preemption();
return (result);
}
int
pthread_join(pthread_t tid, void **status)
{
pthread_thread_t *joinee, *joiner;
if ((joinee = tidtothread(tid)) == NULL_THREADPTR)
return EINVAL;
joiner = CURPTHREAD();
assert_preemption_enabled();
disable_preemption();
pthread_lock(&(joinee->lock));
if (joinee->flags & THREAD_DETACHED) {
pthread_unlock(&(joinee->lock));
enable_preemption();
return EINVAL;
}
pthread_unlock(&(joinee->lock));
enable_preemption();
/*
* Use a mutex here. This avoids specialized handling in the cancel
* and signal code. It works becase the "dead" flag is independent,
* protected by a spinning mutex in the reaper code.
*/
pthread_mutex_lock(&joinee->mutex);
while (!joinee->dead) {
/*
* join must be called with cancelation DEFERRED!
*/
pthread_testcancel();
pthread_cond_wait(&joinee->cond, &joinee->mutex);
}
/*
* Not allowed to detach the target thread if this thread is canceled.
*/
pthread_testcancel();
disable_preemption();
if (status)
*status = (void *) joinee->exitval;
pthread_mutex_unlock(&joinee->mutex);
pthread_destroy_internal(joinee);
enable_preemption();
return 0;
}
/*
* The idle thread exists to spin looking for threads to run, and provide
* a place for pthread_delay() to get called so that in usermode CPU time
* is not wildly consumed.
*/
void *
pthread_idle_function(void *arg)
{
DPRINTF("(%d): starting\n", THISCPU);
/*
* The idle thread is run preemption disabled.
*/
disable_preemption();
while (1) {
assert_interrupts_enabled();
assert_preemption_disabled();
pthread_reap_threads();
/*
* If nothing to schedule call the delay function
*/
if (!pthread_sched_reschedule(RESCHED_INTERNAL, 0))
pthread_delay();
}
return 0;
}
bool kmutex_trylock(kmutex *m)
{
bool success = false;
disable_preemption();
DEBUG_ONLY(check_not_in_irq_handler());
if (!m->owner_task) {
/* Nobody owns this mutex, just make this task own it */
m->owner_task = get_curr_task();
success = true;
if (m->flags & KMUTEX_FL_RECURSIVE)
m->lock_count++;
} else {
/*
* There IS an owner task, but we can still acquire the mutex if:
* - the mutex is recursive
* - the task holding it is actually the current task
*/
if (m->flags & KMUTEX_FL_RECURSIVE) {
if (kmutex_is_curr_task_holding_lock(m)) {
m->lock_count++;
success = true;
}
}
}
enable_preemption();
return success;
}
static spl_t
panic_prologue(const char *str)
{
spl_t s;
if (kdebug_enable) {
ml_set_interrupts_enabled(TRUE);
kdbg_dump_trace_to_file("/var/tmp/panic.trace");
}
s = splhigh();
disable_preemption();
#if defined(__i386__) || defined(__x86_64__)
/* Attempt to display the unparsed panic string */
const char *tstr = str;
kprintf("Panic initiated, string: ");
while (tstr && *tstr)
kprintf("%c", *tstr++);
kprintf("\n");
#endif
panic_safe();
#ifndef __arm__ /* xxx show all panic output for now. */
if( logPanicDataToScreen )
#endif
disable_debug_output = FALSE;
debug_mode = TRUE;
restart:
PANIC_LOCK();
if (panicstr) {
if (cpu_number() != paniccpu) {
PANIC_UNLOCK();
/*
* Wait until message has been printed to identify correct
* cpu that made the first panic.
*/
while (panicwait)
continue;
goto restart;
} else {
nestedpanic +=1;
PANIC_UNLOCK();
Debugger("double panic");
printf("double panic: We are hanging here...\n");
panic_stop();
/* NOTREACHED */
}
}
panicstr = str;
paniccpu = cpu_number();
panicwait = 1;
PANIC_UNLOCK();
return(s);
}
void kmutex_lock(kmutex *m)
{
disable_preemption();
DEBUG_ONLY(check_not_in_irq_handler());
if (!m->owner_task) {
/* Nobody owns this mutex, just make this task own it */
m->owner_task = get_curr_task();
if (m->flags & KMUTEX_FL_RECURSIVE) {
ASSERT(m->lock_count == 0);
m->lock_count++;
}
enable_preemption();
return;
}
if (m->flags & KMUTEX_FL_RECURSIVE) {
ASSERT(m->lock_count > 0);
if (kmutex_is_curr_task_holding_lock(m)) {
m->lock_count++;
enable_preemption();
return;
}
} else {
ASSERT(!kmutex_is_curr_task_holding_lock(m));
}
#if KMUTEX_STATS_ENABLED
m->num_waiters++;
m->max_num_waiters = MAX(m->num_waiters, m->max_num_waiters);
#endif
task_set_wait_obj(get_curr_task(), WOBJ_KMUTEX, m, &m->wait_list);
enable_preemption();
kernel_yield(); // Go to sleep until someone else is holding the lock.
/* ------------------- We've been woken up ------------------- */
#if KMUTEX_STATS_ENABLED
m->num_waiters--;
#endif
/* Now for sure this task should hold the mutex */
ASSERT(kmutex_is_curr_task_holding_lock(m));
/*
* DEBUG check: in case we went to sleep with a recursive mutex, then the
* lock_count must be just 1 now.
*/
if (m->flags & KMUTEX_FL_RECURSIVE) {
ASSERT(m->lock_count == 1);
}
}
__private_extern__ kern_return_t
chudxnu_cpusig_send(int otherCPU, uint32_t request_code)
{
int thisCPU;
kern_return_t retval = KERN_FAILURE;
chudcpu_signal_request_t request;
uint64_t deadline;
chudcpu_data_t *target_chudp;
boolean_t old_level;
disable_preemption();
// force interrupts on for a cross CPU signal.
old_level = chudxnu_set_interrupts_enabled(TRUE);
thisCPU = cpu_number();
if ((unsigned) otherCPU < real_ncpus &&
thisCPU != otherCPU &&
cpu_data_ptr[otherCPU]->cpu_running) {
target_chudp = (chudcpu_data_t *)
cpu_data_ptr[otherCPU]->cpu_chud;
/* Fill out request */
request.req_sync = 0xFFFFFFFF; /* set sync flag */
//request.req_type = CPRQchud; /* set request type */
request.req_code = request_code; /* set request */
KERNEL_DEBUG_CONSTANT(
MACHDBG_CODE(DBG_MACH_CHUD,
CHUD_CPUSIG_SEND) | DBG_FUNC_NONE,
otherCPU, request_code, 0, 0, 0);
/*
* Insert the new request in the target cpu's request queue
* and signal target cpu.
*/
mpenqueue_tail(&target_chudp->cpu_request_queue,
&request.req_entry);
i386_signal_cpu(otherCPU, MP_CHUD, ASYNC);
/* Wait for response or timeout */
deadline = mach_absolute_time() + LockTimeOut;
while (request.req_sync != 0) {
if (mach_absolute_time() > deadline) {
panic("chudxnu_cpusig_send(%d,%d) timed out\n",
otherCPU, request_code);
}
cpu_pause();
}
retval = KERN_SUCCESS;
} else {
retval = KERN_INVALID_ARGUMENT;
}
chudxnu_set_interrupts_enabled(old_level);
enable_preemption();
return retval;
}
static void
swtch_continue(void)
{
register processor_t myprocessor;
boolean_t result;
disable_preemption();
myprocessor = current_processor();
result = !SCHED(processor_queue_empty)(myprocessor) || rt_runq.count > 0;
enable_preemption();
thread_syscall_return(result);
/*NOTREACHED*/
}
void
log(__unused int level, char *fmt, ...)
{
va_list listp;
#ifdef lint
level++;
#endif /* lint */
#ifdef MACH_BSD
disable_preemption();
va_start(listp, fmt);
_doprnt(fmt, &listp, conslog_putc, 0);
va_end(listp);
enable_preemption();
#endif
}
/*
* Start up the first thread on a CPU.
* First thread is specified for the master CPU.
*/
void
cpu_launch_first_thread(
register thread_t th)
{
register int mycpu;
mycpu = cpu_number();
#if MACH_ASSERT
if (watchacts & WA_BOOT)
printf("cpu_launch_first_thread(%x) cpu=%d\n", th, mycpu);
#endif /* MACH_ASSERT */
cpu_up(mycpu);
start_timer(&kernel_timer[mycpu]);
/*
* Block all interrupts for choose_thread.
*/
(void) splhigh();
if (th == THREAD_NULL) {
th = cpu_to_processor(mycpu)->idle_thread;
if (th == THREAD_NULL || !rem_runq(th))
panic("cpu_launch_first_thread");
}
rtclock_reset(); /* start realtime clock ticking */
PMAP_ACTIVATE_KERNEL(mycpu);
thread_machine_set_current(th);
thread_lock(th);
th->state &= ~TH_UNINT;
thread_unlock(th);
timer_switch(&th->system_timer);
PMAP_ACTIVATE_USER(th->top_act, mycpu);
assert(mycpu == cpu_number());
/* The following is necessary to keep things balanced */
disable_preemption();
load_context(th);
/*NOTREACHED*/
}
void kmutex_unlock(kmutex *m)
{
disable_preemption();
DEBUG_ONLY(check_not_in_irq_handler());
ASSERT(kmutex_is_curr_task_holding_lock(m));
if (m->flags & KMUTEX_FL_RECURSIVE) {
ASSERT(m->lock_count > 0);
if (--m->lock_count > 0) {
enable_preemption();
return;
}
// m->lock_count == 0: we have to really unlock the mutex
}
m->owner_task = NULL;
/* Unlock one task waiting to acquire the mutex 'm' (if any) */
if (!list_is_empty(&m->wait_list)) {
wait_obj *task_wo =
list_first_obj(&m->wait_list, wait_obj, wait_list_node);
task_info *ti = CONTAINER_OF(task_wo, task_info, wobj);
m->owner_task = ti;
if (m->flags & KMUTEX_FL_RECURSIVE)
m->lock_count++;
ASSERT(ti->state == TASK_STATE_SLEEPING);
task_reset_wait_obj(ti);
} // if (!list_is_empty(&m->wait_list))
enable_preemption();
}
void soft_interrupt_entry(regs *r)
{
const int int_num = regs_intnum(r);
ASSERT(!are_interrupts_enabled());
if (int_num == SYSCALL_SOFT_INTERRUPT)
DEBUG_check_preemption_enabled_for_usermode();
push_nested_interrupt(int_num);
disable_preemption();
if (int_num == SYSCALL_SOFT_INTERRUPT) {
enable_interrupts_forced();
{
handle_syscall(r);
}
disable_interrupts_forced(); /* restore IF = 0 */
} else {
/*
* General rule: fault handlers get control with interrupts disabled but
* they are supposed to call enable_interrupts_forced() ASAP.
*/
handle_fault(r);
/* Faults are expected to return with interrupts disabled. */
ASSERT(!are_interrupts_enabled());
}
enable_preemption();
pop_nested_interrupt();
if (int_num == SYSCALL_SOFT_INTERRUPT)
DEBUG_check_preemption_enabled_for_usermode();
}
void
panic(const char *str, ...)
{
va_list listp;
spl_t s;
thread_t thread;
wait_queue_t wq;
#if defined(__i386__) || defined(__x86_64__)
/* Attempt to display the unparsed panic string */
const char *tstr = str;
kprintf("Panic initiated, string: ");
while (tstr && *tstr)
kprintf("%c", *tstr++);
kprintf("\n");
#endif
if (kdebug_enable)
kdbg_dump_trace_to_file("/var/tmp/panic.trace");
s = splhigh();
disable_preemption();
panic_safe();
thread = current_thread(); /* Get failing thread */
wq = thread->wait_queue; /* Save the old value */
thread->wait_queue = NULL; /* Clear the wait so we do not get double panics when we try locks */
if( logPanicDataToScreen )
disable_debug_output = FALSE;
debug_mode = TRUE;
/* panic_caller is initialized to 0. If set, don't change it */
if ( ! panic_caller )
panic_caller = (unsigned long)(char *)__builtin_return_address(0);
restart:
PANIC_LOCK();
if (panicstr) {
if (cpu_number() != paniccpu) {
PANIC_UNLOCK();
/*
* Wait until message has been printed to identify correct
* cpu that made the first panic.
*/
while (panicwait)
continue;
goto restart;
} else {
nestedpanic +=1;
PANIC_UNLOCK();
Debugger("double panic");
printf("double panic: We are hanging here...\n");
panic_stop();
/* NOTREACHED */
}
}
panicstr = str;
paniccpu = cpu_number();
panicwait = 1;
PANIC_UNLOCK();
kdb_printf("panic(cpu %d caller 0x%lx): ", (unsigned) paniccpu, panic_caller);
if (str) {
va_start(listp, str);
_doprnt(str, &listp, consdebug_putc, 0);
va_end(listp);
}
kdb_printf("\n");
/*
* Release panicwait indicator so that other cpus may call Debugger().
*/
panicwait = 0;
Debugger("panic");
/*
* Release panicstr so that we can handle normally other panics.
*/
PANIC_LOCK();
panicstr = (char *)0;
PANIC_UNLOCK();
thread->wait_queue = wq; /* Restore the wait queue */
if (return_on_panic) {
panic_normal();
enable_preemption();
splx(s);
return;
}
kdb_printf("panic: We are hanging here...\n");
panic_stop();
/* NOTREACHED */
}
__private_extern__ void
chudxnu_disable_preemption(void)
{
disable_preemption();
}
boolean_t
kdp_i386_trap(
unsigned int trapno,
x86_saved_state64_t *saved_state,
kern_return_t result,
vm_offset_t va
)
{
unsigned int exception, subcode = 0, code;
if (trapno != T_INT3 && trapno != T_DEBUG) {
kprintf("Debugger: Unexpected kernel trap number: "
"0x%x, RIP: 0x%llx, CR2: 0x%llx\n",
trapno, saved_state->isf.rip, saved_state->cr2);
if (!kdp.is_conn)
return FALSE;
}
mp_kdp_enter();
kdp_callouts(KDP_EVENT_ENTER);
if (saved_state->isf.rflags & EFL_TF) {
enable_preemption_no_check();
}
switch (trapno) {
case T_DIVIDE_ERROR:
exception = EXC_ARITHMETIC;
code = EXC_I386_DIVERR;
break;
case T_OVERFLOW:
exception = EXC_SOFTWARE;
code = EXC_I386_INTOFLT;
break;
case T_OUT_OF_BOUNDS:
exception = EXC_ARITHMETIC;
code = EXC_I386_BOUNDFLT;
break;
case T_INVALID_OPCODE:
exception = EXC_BAD_INSTRUCTION;
code = EXC_I386_INVOPFLT;
break;
case T_SEGMENT_NOT_PRESENT:
exception = EXC_BAD_INSTRUCTION;
code = EXC_I386_SEGNPFLT;
subcode = (unsigned int)saved_state->isf.err;
break;
case T_STACK_FAULT:
exception = EXC_BAD_INSTRUCTION;
code = EXC_I386_STKFLT;
subcode = (unsigned int)saved_state->isf.err;
break;
case T_GENERAL_PROTECTION:
exception = EXC_BAD_INSTRUCTION;
code = EXC_I386_GPFLT;
subcode = (unsigned int)saved_state->isf.err;
break;
case T_PAGE_FAULT:
exception = EXC_BAD_ACCESS;
code = result;
subcode = (unsigned int)va;
break;
case T_WATCHPOINT:
exception = EXC_SOFTWARE;
code = EXC_I386_ALIGNFLT;
break;
case T_DEBUG:
case T_INT3:
exception = EXC_BREAKPOINT;
code = EXC_I386_BPTFLT;
break;
default:
exception = EXC_BAD_INSTRUCTION;
code = trapno;
break;
}
if (current_cpu_datap()->cpu_fatal_trap_state) {
current_cpu_datap()->cpu_post_fatal_trap_state = saved_state;
saved_state = current_cpu_datap()->cpu_fatal_trap_state;
}
kdp_raise_exception(exception, code, subcode, saved_state);
/* If the instruction single step bit is set, disable kernel preemption
*/
if (saved_state->isf.rflags & EFL_TF) {
disable_preemption();
}
kdp_callouts(KDP_EVENT_EXIT);
mp_kdp_exit();
return TRUE;
}
struct savearea * interrupt(
int type,
struct savearea *ssp,
unsigned int dsisr,
unsigned int dar)
{
int current_cpu;
struct per_proc_info *proc_info;
uint64_t now;
thread_t thread;
disable_preemption();
perfCallback fn = perfIntHook;
if(fn) { /* Is there a hook? */
if(fn(type, ssp, dsisr, dar) == KERN_SUCCESS) return ssp; /* If it succeeds, we are done... */
}
#if CONFIG_DTRACE
if(tempDTraceIntHook) { /* Is there a hook? */
if(tempDTraceIntHook(type, ssp, dsisr, dar) == KERN_SUCCESS) return ssp; /* If it succeeds, we are done... */
}
#endif
#if 0
{
extern void fctx_text(void);
fctx_test();
}
#endif
current_cpu = cpu_number();
proc_info = getPerProc();
switch (type) {
case T_DECREMENTER:
KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_EXCP_DECI, 0) | DBG_FUNC_NONE,
isync_mfdec(), (unsigned int)ssp->save_srr0, 0, 0, 0);
now = mach_absolute_time(); /* Find out what time it is */
if(now >= proc_info->pms.pmsPop) { /* Is it time for power management state change? */
pmsStep(1); /* Yes, advance step */
now = mach_absolute_time(); /* Get the time again since we ran a bit */
}
thread = current_thread(); /* Find ourselves */
if(thread->machine.qactTimer != 0) { /* Is the timer set? */
if (thread->machine.qactTimer <= now) { /* It is set, has it popped? */
thread->machine.qactTimer = 0; /* Clear single shot timer */
if((unsigned int)thread->machine.vmmControl & 0xFFFFFFFE) { /* Are there any virtual machines? */
vmm_timer_pop(thread); /* Yes, check out them out... */
}
}
}
etimer_intr(USER_MODE(ssp->save_srr1), ssp->save_srr0); /* Handle event timer */
break;
case T_INTERRUPT:
/* Call the platform interrupt routine */
counter(c_incoming_interrupts++);
KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_EXCP_INTR, 0) | DBG_FUNC_START,
current_cpu, (unsigned int)ssp->save_srr0, 0, 0, 0);
#if CONFIG_DTRACE && (DEVELOPMENT || DEBUG )
DTRACE_INT5(interrupt__start, void *, proc_info->interrupt_nub, int, proc_info->interrupt_source,
void *, proc_info->interrupt_target, IOInterruptHandler, proc_info->interrupt_handler,
void *, proc_info->interrupt_refCon);
#endif
proc_info->interrupt_handler(
proc_info->interrupt_target,
proc_info->interrupt_refCon,
proc_info->interrupt_nub,
proc_info->interrupt_source);
#if CONFIG_DTRACE && (DEVELOPMENT || DEBUG )
DTRACE_INT5(interrupt__complete, void *, proc_info->interrupt_nub, int, proc_info->interrupt_source,
void *, proc_info->interrupt_target, IOInterruptHandler, proc_info->interrupt_handler,
void *, proc_info->interrupt_refCon);
#endif
KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_EXCP_INTR, 0) | DBG_FUNC_END,
0, 0, 0, 0, 0);
break;
case T_SIGP:
/* Did the other processor signal us? */
cpu_signal_handler();
break;
case T_SHUTDOWN:
cpu_doshutdown();
panic("returning from cpu_doshutdown()\n");
break;
default:
if (!Call_Debugger(type, ssp))
unresolved_kernel_trap(type, ssp, dsisr, dar, NULL);
break;
}
enable_preemption();
return ssp;
}
