#include <lunaix/mm/kalloc.h>
#include <lunaix/mm/pmm.h>
+#include <lunaix/mm/valloc.h>
#include <lunaix/mm/vmm.h>
#include <lunaix/process.h>
#include <lunaix/sched.h>
void
run(struct proc_info* proc)
{
- if (!(__current->state & ~PROC_RUNNING)) {
- __current->state = PROC_STOPPED;
- }
- proc->state = PROC_RUNNING;
-
- // XXX: 我们需要这一步吗？
- // tss_update_esp(__current->intr_ctx.esp);
+ proc->state = PS_RUNNING;
+
+ /*
+ 将tss.esp0设置为上次调度前的esp值。
+ 当处理信号时，上下文信息是不会恢复的，而是保存在用户栈中，然后直接跳转进位于用户空间的sig_wrapper进行
+ 信号的处理。当用户自定义的信号处理函数返回时，sigreturn的系统调用才开始进行上下文的恢复（或者说是进行
+ 另一次调度。
+ 由于这中间没有进行地址空间的交换，所以第二次跳转使用的是同一个内核栈，而之前默认tss.esp0的值是永远指向最顶部
+ 这样一来就有可能会覆盖更早的上下文信息（比如嵌套的信号捕获函数）
+ */
+ tss_update_esp(proc->intr_ctx.registers.esp);
apic_done_servicing();
asm volatile("pushl %0\n"
- "jmp switch_to\n" ::"r"(proc)); // kernel/asm/x86/interrupt.S
+ "jmp switch_to\n" ::"r"(proc)
+ : "memory"); // kernel/asm/x86/interrupt.S
+}
+
+int
+can_schedule(struct proc_info* proc)
+{
+ if (__SIGTEST(proc->sig_pending, _SIGCONT)) {
+ __SIGCLEAR(proc->sig_pending, _SIGSTOP);
+ } else if (__SIGTEST(proc->sig_pending, _SIGSTOP)) {
+ // 如果进程受到SIGSTOP，则该进程不给予调度。
+ return 0;
+ }
+
+ return 1;
+}
+
+void
+check_sleepers()
+{
+ struct proc_info* leader = &sched_ctx._procs[0];
+ struct proc_info *pos, *n;
+ time_t now = clock_systime();
+ llist_for_each(pos, n, &leader->sleep.sleepers, sleep.sleepers)
+ {
+ if (PROC_TERMINATED(pos->state)) {
+ goto del;
+ }
+
+ time_t wtime = pos->sleep.wakeup_time;
+ time_t atime = pos->sleep.alarm_time;
+
+ if (wtime && now >= wtime) {
+ pos->sleep.wakeup_time = 0;
+ pos->state = PS_STOPPED;
+ }
+
+ if (atime && now >= atime) {
+ pos->sleep.alarm_time = 0;
+ __SIGSET(pos->sig_pending, _SIGALRM);
+ }
+
+ if (!wtime && !atime) {
+ del:
+ llist_delete(&pos->sleep.sleepers);
+ }
+ }
}
void
struct proc_info* next;
int prev_ptr = sched_ctx.procs_index;
int ptr = prev_ptr;
+
+ if (!(__current->state & ~PS_RUNNING)) {
+ __current->state = PS_STOPPED;
+ }
+
+ check_sleepers();
+
// round-robin scheduler
+redo:
do {
ptr = (ptr + 1) % sched_ctx.ptable_len;
next = &sched_ctx._procs[ptr];
- } while (next->state != PROC_STOPPED && ptr != prev_ptr);
+ } while (next->state != PS_STOPPED && ptr != prev_ptr);
sched_ctx.procs_index = ptr;
- run(next);
-}
+ if (!can_schedule(next)) {
+ // 如果该进程不给予调度，则尝试重新选择
+ goto redo;
+ }
-static void
-proc_timer_callback(struct proc_info* proc)
-{
- proc->timer = NULL;
- proc->state = PROC_STOPPED;
+ run(next);
}
__DEFINE_LXSYSCALL1(unsigned int, sleep, unsigned int, seconds)
{
- // FIXME: sleep的实现或许需要改一下。专门绑一个计时器好像没有必要……
if (!seconds) {
return 0;
}
- if (__current->timer) {
- return __current->timer->counter / timer_context()->running_frequency;
+ if (__current->sleep.wakeup_time) {
+ return (__current->sleep.wakeup_time - clock_systime()) / 1000U;
}
- struct lx_timer* timer =
- timer_run_second(seconds, proc_timer_callback, __current, 0);
- __current->timer = timer;
+ __current->sleep.wakeup_time = clock_systime() + seconds * 1000;
+ llist_append(&sched_ctx._procs[0].sleep.sleepers,
+ &__current->sleep.sleepers);
+
__current->intr_ctx.registers.eax = seconds;
- __current->state = PROC_BLOCKED;
+ __current->state = PS_BLOCKED;
schedule();
}
+__DEFINE_LXSYSCALL1(unsigned int, alarm, unsigned int, seconds)
+{
+ time_t prev_ddl = __current->sleep.alarm_time;
+ time_t now = clock_systime();
+
+ __current->sleep.alarm_time = seconds ? now + seconds * 1000 : 0;
+
+ if (llist_empty(&__current->sleep.sleepers)) {
+ llist_append(&sched_ctx._procs[0].sleep.sleepers,
+ &__current->sleep.sleepers);
+ }
+
+ return prev_ddl ? (prev_ddl - now) / 1000 : 0;
+}
+
__DEFINE_LXSYSCALL1(void, exit, int, status)
{
terminate_proc(status);
+ schedule();
}
__DEFINE_LXSYSCALL(void, yield)
return _wait(pid, status, options);
}
+__DEFINE_LXSYSCALL(int, geterrno)
+{
+ return __current->k_status;
+}
+
pid_t
_wait(pid_t wpid, int* status, int options)
{
llist_for_each(proc, n, &__current->children, siblings)
{
if (!~wpid || proc->pid == wpid || proc->pgid == -wpid) {
- if (proc->state == PROC_TERMNAT && !options) {
- status_flags |= PROCTERM;
+ if (proc->state == PS_TERMNAT && !options) {
+ status_flags |= PEXITTERM;
goto done;
}
- if (proc->state == PROC_STOPPED && (options & WUNTRACED)) {
- status_flags |= PROCSTOP;
+ if (proc->state == PS_STOPPED && (options & WUNTRACED)) {
+ status_flags |= PEXITSTOP;
goto done;
}
}
done:
cpu_disable_interrupt();
- *status = (proc->exit_code & 0xffff) | status_flags;
+ status_flags |= PEXITSIG * (proc->sig_inprogress != 0);
+ if (status) {
+ *status = proc->exit_code | status_flags;
+ }
return destroy_process(proc->pid);
}
alloc_process()
{
pid_t i = 0;
- for (;
- i < sched_ctx.ptable_len && sched_ctx._procs[i].state != PROC_DESTROY;
+ for (; i < sched_ctx.ptable_len && sched_ctx._procs[i].state != PS_DESTROY;
i++)
;
struct proc_info* proc = &sched_ctx._procs[i];
memset(proc, 0, sizeof(*proc));
- proc->state = PROC_CREATED;
+ proc->state = PS_CREATED;
proc->pid = i;
proc->created = clock_systime();
proc->pgid = proc->pid;
+ proc->fdtable = vzalloc(sizeof(struct v_fdtable));
llist_init_head(&proc->mm.regions);
llist_init_head(&proc->children);
llist_init_head(&proc->grp_member);
+ llist_init_head(&proc->sleep.sleepers);
return proc;
}
{
assert(process == &sched_ctx._procs[process->pid]);
- if (process->state != PROC_CREATED) {
- __current->k_status = LXINVL;
+ if (process->state != PS_CREATED) {
+ __current->k_status = EINVAL;
return;
}
// every process is the child of first process (pid=1)
- if (process->parent) {
- llist_append(&process->parent->children, &process->siblings);
- } else {
- process->parent = &sched_ctx._procs[0];
+ if (!process->parent) {
+ process->parent = &sched_ctx._procs[1];
}
- process->state = PROC_STOPPED;
+ llist_append(&process->parent->children, &process->siblings);
+
+ process->state = PS_STOPPED;
}
// from <kernel/process.c>
{
int index = pid;
if (index <= 0 || index > sched_ctx.ptable_len) {
- __current->k_status = LXINVLDPID;
+ __current->k_status = EINVAL;
return;
}
struct proc_info* proc = &sched_ctx._procs[index];
- proc->state = PROC_DESTROY;
+ proc->state = PS_DESTROY;
llist_delete(&proc->siblings);
struct mm_region *pos, *n;
void
terminate_proc(int exit_code)
{
- __current->state = PROC_TERMNAT;
+ __current->state = PS_TERMNAT;
__current->exit_code = exit_code;
- schedule();
+ __SIGSET(__current->parent->sig_pending, _SIGCHLD);
}
struct proc_info*
// 如果其父进程的状态是terminated 或 destroy中的一种
// 或者其父进程是在该进程之后创建的，那么该进程为孤儿进程
- return (parent->state & PROC_TERMMASK) || parent->created > proc->created;
+ return PROC_TERMINATED(parent->state) || parent->created > proc->created;
}
\ No newline at end of file
git://scm.lunaixsky.com / lunaix-os.git / blobdiff