#include <cputypes.h>
#include <cpus.h>
#include <platforms.h>
-#include <task_swapper.h>
#include <kern/ast.h>
#include <kern/counters.h>
#include <kern/cpu_number.h>
#include <kern/misc_protos.h>
#include <kern/queue.h>
-#include <kern/sched.h>
#include <kern/sched_prim.h>
#include <kern/thread.h>
#include <kern/thread_act.h>
#include <kern/processor.h>
#include <kern/spl.h>
#include <mach/policy.h>
-#if TASK_SWAPPER
-#include <kern/task_swap.h>
-#endif /* TASK_SWAPPER */
volatile ast_t need_ast[NCPUS];
void
ast_taken(
- boolean_t preemption,
- ast_t mask,
- boolean_t interrupt
+ ast_t reasons,
+ boolean_t enable
)
{
- register thread_t self = current_thread();
- register processor_t mypr;
- register ast_t reasons;
- register int mycpu;
- thread_act_t act = self->top_act;
-#ifdef MACH_BSD
- extern void bsd_ast(thread_act_t);
- extern void bsdinit_task(void);
-#endif
+ register int mycpu;
+ register processor_t myprocessor;
+ register thread_t self = current_thread();
+ boolean_t preempt_trap = (reasons == AST_PREEMPT);
- mp_disable_preemption();
+ disable_preemption();
mycpu = cpu_number();
- reasons = need_ast[mycpu] & mask;
+ reasons &= need_ast[mycpu];
need_ast[mycpu] &= ~reasons;
- mp_enable_preemption();
-
- ml_set_interrupts_enabled(interrupt);
+ enable_preemption();
/*
* No ast for an idle thread
*/
if (self->state & TH_IDLE)
- return;
+ goto enable_and_return;
/*
- * Check for preemption
+ * Check for urgent preemption
*/
- if ((reasons & AST_URGENT) && (wait_queue_assert_possible(self))) {
- reasons &= ~AST_URGENT;
- if ((reasons & (AST_BLOCK|AST_QUANTUM)) == 0) {
- mp_disable_preemption();
- mypr = current_processor();
- if (csw_needed(self, mypr)) {
- reasons |= (mypr->first_quantum ? AST_BLOCK : AST_QUANTUM);
- }
- mp_enable_preemption();
- }
- if (reasons & (AST_BLOCK | AST_QUANTUM)) {
+ if ((reasons & AST_URGENT) && wait_queue_assert_possible(self)) {
+ if (reasons & AST_BLOCK) {
counter(c_ast_taken_block++);
- thread_block_reason((void (*)(void))0,
- (reasons & (AST_BLOCK | AST_QUANTUM)));
+ thread_block_reason((void (*)(void))0, AST_BLOCK);
}
+
+ reasons &= ~AST_PREEMPT;
if (reasons == 0)
- return;
+ goto enable_and_return;
}
+ if (preempt_trap)
+ goto enable_and_return;
+
+ ml_set_interrupts_enabled(enable);
+
#ifdef MACH_BSD
/*
* Check for BSD hardcoded hooks
*/
if (reasons & AST_BSD) {
- thread_ast_clear(act,AST_BSD);
+ extern void bsd_ast(thread_act_t act);
+ thread_act_t act = self->top_act;
+
+ thread_ast_clear(act, AST_BSD);
bsd_ast(act);
}
if (reasons & AST_BSD_INIT) {
- thread_ast_clear(act,AST_BSD_INIT);
+ extern void bsdinit_task(void);
+
+ thread_ast_clear(self->top_act, AST_BSD_INIT);
bsdinit_task();
}
#endif
-#if TASK_SWAPPER
- /* must be before AST_APC */
- if (reasons & AST_SWAPOUT) {
- spl_t s;
- swapout_ast();
- s = splsched();
- mp_disable_preemption();
- mycpu = cpu_number();
- if (need_ast[mycpu] & AST_APC) {
- /* generated in swapout_ast() to get suspended */
- reasons |= AST_APC; /* process now ... */
- need_ast[mycpu] &= ~AST_APC; /* ... and not later */
- }
- mp_enable_preemption();
- splx(s);
- }
-#endif /* TASK_SWAPPER */
-
/*
* migration APC hook
*/
}
/*
- * thread_block needs to know if the thread's quantum
- * expired so the thread can be put on the tail of
- * run queue. One of the previous actions might well
- * have woken a high-priority thread, so we also use
- * csw_needed check.
+ * Check for normal preemption
*/
- reasons &= (AST_BLOCK | AST_QUANTUM);
- if (reasons == 0) {
- mp_disable_preemption();
- mypr = current_processor();
- if (csw_needed(self, mypr)) {
- reasons = (mypr->first_quantum ? AST_BLOCK : AST_QUANTUM);
- }
- mp_enable_preemption();
- }
- if ((reasons & (AST_BLOCK | AST_QUANTUM)) &&
- (wait_queue_assert_possible(self))) {
+ reasons &= AST_BLOCK;
+ if (reasons == 0) {
+ disable_preemption();
+ myprocessor = current_processor();
+ if (csw_needed(self, myprocessor))
+ reasons = AST_BLOCK;
+ enable_preemption();
+ }
+ if ( (reasons & AST_BLOCK) &&
+ wait_queue_assert_possible(self) ) {
counter(c_ast_taken_block++);
- /*
- * JMM - SMP machines don't like blocking at a continuation
- * here - why not? Could be a combination of set_state and
- * suspension on the thread_create_running API?
- *
- * thread_block_reason(thread_exception_return, reasons);
- */
- thread_block_reason((void (*)(void))0, reasons);
+ thread_block_reason(thread_exception_return, AST_BLOCK);
}
+
+ goto just_return;
+
+enable_and_return:
+ ml_set_interrupts_enabled(enable);
+
+just_return:
+ return;
}
void
ast_check(void)
{
- register int mycpu;
+ register int mycpu;
register processor_t myprocessor;
- register thread_t thread = current_thread();
- spl_t s = splsched();
+ register thread_t self = current_thread();
+ spl_t s;
- mp_disable_preemption();
+ s = splsched();
mycpu = cpu_number();
/*
* Check processor state for ast conditions.
*/
myprocessor = cpu_to_processor(mycpu);
- switch(myprocessor->state) {
- case PROCESSOR_OFF_LINE:
- case PROCESSOR_IDLE:
- case PROCESSOR_DISPATCHING:
+ switch (myprocessor->state) {
+
+ case PROCESSOR_OFF_LINE:
+ case PROCESSOR_IDLE:
+ case PROCESSOR_DISPATCHING:
/*
* No ast.
*/
- break;
+ break;
-#if NCPUS > 1
- case PROCESSOR_ASSIGN:
- /*
+ case PROCESSOR_ASSIGN:
+ /*
* Need ast to force action thread onto processor.
- *
- * XXX Should check if action thread is already there.
*/
ast_on(AST_BLOCK);
break;
-#endif /* NCPUS > 1 */
- case PROCESSOR_RUNNING:
- case PROCESSOR_SHUTDOWN:
+ case PROCESSOR_RUNNING:
+ case PROCESSOR_SHUTDOWN:
/*
- * Propagate thread ast to processor. If we already
- * need an ast, don't look for more reasons.
+ * Propagate thread ast to processor.
*/
- ast_propagate(current_act()->ast);
- if (ast_needed(mycpu))
- break;
+ ast_propagate(self->top_act->ast);
/*
* Context switch check.
*/
- if (csw_needed(thread, myprocessor)) {
- ast_on((myprocessor->first_quantum ?
- AST_BLOCK : AST_QUANTUM));
- }
+ if (csw_needed(self, myprocessor))
+ ast_on(AST_BLOCK);
break;
- default:
- panic("ast_check: Bad processor state");
+ default:
+ panic("ast_check: Bad processor state");
}
- mp_enable_preemption();
+
splx(s);
}
void
ast_on(ast_t reason)
{
- boolean_t intr;
+ boolean_t enable;
- intr = ml_set_interrupts_enabled(FALSE);
+ enable = ml_set_interrupts_enabled(FALSE);
ast_on_fast(reason);
- (void *)ml_set_interrupts_enabled(intr);
+ (void)ml_set_interrupts_enabled(enable);
}
void
projects / apple / xnu.git / blobdiff