Advertisement
Not a member of Pastebin yet?
Sign Up,
it unlocks many cool features!
- #include "types.h"
- #include "defs.h"
- #include "param.h"
- #include "mmu.h"
- #include "x86.h"
- #include "proc.h"
- #include "spinlock.h"
- struct {
- struct spinlock lock;
- struct proc proc[NPROC];
- } ptable;
- static struct proc *initproc;
- static int num_tickets=0; //mona2
- unsigned long winner;
- int nextpid = 1;
- extern void forkret(void);
- extern void trapret(void);
- ///// mona2 lcg invariant //not working because of uint32_t
- /*
- static uint32_t temper(uint32_t x)
- {
- x ^= x>>11;
- x ^= x<<7 & 0x9D2C5680;
- x ^= x<<15 & 0xEFC60000;
- x ^= x>>18;
- return x;
- }
- uint32_t lcg64_temper(uint64_t *seed)
- {
- *seed = 6364136223846793005ULL * *seed + 1;
- return temper(*seed >> 32);
- }
- */
- static
- unsigned long
- lcg_rand(unsigned long a)
- {
- return (a * 279470273UL) % 4294967291UL;
- }
- static void wakeup1(void *chan);
- void
- pinit(void)
- {
- initlock(&ptable.lock, "ptable");
- }
- // Look in the process table for an UNUSED proc.
- // If found, change state to EMBRYO and initialize
- // state required to run in the kernel.
- // Otherwise return 0.
- static struct proc*
- allocproc(void)
- {
- struct proc *p;
- char *sp;
- acquire(&ptable.lock);
- for(p = ptable.proc; p < &ptable.proc[NPROC]; p++)
- if(p->state == UNUSED)
- {
- goto found;
- p->tickets=CREATION_TICKET; //mona2
- num_tickets+=CREATION_TICKET; //mona2
- }
- release(&ptable.lock);
- return 0;
- found:
- p->state = EMBRYO;
- p->pid = nextpid++;
- release(&ptable.lock);
- // Allocate kernel stack if possible.
- if((p->kstack = kalloc()) == 0){
- p->state = UNUSED;
- return 0;
- }
- sp = p->kstack + KSTACKSIZE;
- // Leave room for trap frame.
- sp -= sizeof *p->tf;
- p->tf = (struct trapframe*)sp;
- // Set up new context to start executing at forkret,
- // which returns to trapret.
- sp -= 4;
- *(uint*)sp = (uint)trapret;
- sp -= sizeof *p->context;
- p->context = (struct context*)sp;
- memset(p->context, 0, sizeof *p->context);
- p->context->eip = (uint)forkret;
- return p;
- }
- // Set up first user process.
- void
- userinit(void)
- {
- struct proc *p;
- extern char _binary_initcode_start[], _binary_initcode_size[];
- p = allocproc();
- acquire(&ptable.lock);
- initproc = p;
- if((p->pgdir = setupkvm()) == 0)
- panic("userinit: out of memory?");
- inituvm(p->pgdir, _binary_initcode_start, (int)_binary_initcode_size);
- p->sz = PGSIZE;
- memset(p->tf, 0, sizeof(*p->tf));
- p->tf->cs = (SEG_UCODE << 3) | DPL_USER;
- p->tf->ds = (SEG_UDATA << 3) | DPL_USER;
- p->tf->es = p->tf->ds;
- p->tf->ss = p->tf->ds;
- p->tf->eflags = FL_IF;
- p->tf->esp = PGSIZE;
- p->tf->eip = 0; // beginning of initcode.S
- safestrcpy(p->name, "initcode", sizeof(p->name));
- p->cwd = namei("/");
- p->state = RUNNABLE;
- p->tickets=CREATION_TICKET;
- release(&ptable.lock);
- }
- // Grow current process's memory by n bytes.
- // Return 0 on success, -1 on failure.
- int
- growproc(int n)
- {
- uint sz;
- sz = proc->sz;
- if(n > 0){
- if((sz = allocuvm(proc->pgdir, sz, sz + n)) == 0)
- return -1;
- } else if(n < 0){
- if((sz = deallocuvm(proc->pgdir, sz, sz + n)) == 0)
- return -1;
- }
- proc->sz = sz;
- switchuvm(proc);
- return 0;
- }
- // Create a new process copying p as the parent.
- // Sets up stack to return as if from system call.
- // Caller must set state of returned proc to RUNNABLE.
- int
- fork(void)
- {
- int i, pid;
- struct proc *np;
- // Allocate process.
- if((np = allocproc()) == 0)
- return -1;
- // Copy process state from p.
- if((np->pgdir = copyuvm(proc->pgdir, proc->sz)) == 0){
- kfree(np->kstack);
- np->kstack = 0;
- np->state = UNUSED;
- return -1;
- }
- np->sz = proc->sz;
- np->parent = proc;
- *np->tf = *proc->tf;
- // Clear %eax so that fork returns 0 in the child.
- np->tf->eax = 0;
- for(i = 0; i < NOFILE; i++)
- if(proc->ofile[i])
- np->ofile[i] = filedup(proc->ofile[i]);
- np->cwd = idup(proc->cwd);
- pid = np->pid;
- np->state = RUNNABLE;
- safestrcpy(np->name, proc->name, sizeof(proc->name));
- return pid;
- }
- // Exit the current process. Does not return.
- // An exited process remains in the zombie state
- // until its parent calls wait() to find out it exited.
- void
- exit(void)
- {
- struct proc *p;
- int fd;
- if(proc == initproc)
- panic("init exiting");
- // Close all open files.
- for(fd = 0; fd < NOFILE; fd++){
- if(proc->ofile[fd]){
- fileclose(proc->ofile[fd]);
- proc->ofile[fd] = 0;
- }
- }
- iput(proc->cwd);
- proc->cwd = 0;
- acquire(&ptable.lock);
- // Parent might be sleeping in wait().
- wakeup1(proc->parent);
- // Pass abandoned children to init.
- for(p = ptable.proc; p < &ptable.proc[NPROC]; p++){
- if(p->parent == proc){
- p->parent = initproc;
- if(p->state == ZOMBIE)
- wakeup1(initproc);
- }
- }
- // Jump into the scheduler, never to return.
- proc->state = ZOMBIE;
- sched();
- panic("zombie exit");
- }
- // Wait for a child process to exit and return its pid.
- // Return -1 if this process has no children.
- int
- wait(void)
- {
- struct proc *p;
- int havekids, pid;
- acquire(&ptable.lock);
- for(;;){
- // Scan through table looking for zombie children.
- havekids = 0;
- for(p = ptable.proc; p < &ptable.proc[NPROC]; p++){
- if(p->parent != proc)
- continue;
- havekids = 1;
- if(p->state == ZOMBIE){
- // Found one.
- pid = p->pid;
- kfree(p->kstack);
- p->kstack = 0;
- freevm(p->pgdir);
- p->state = UNUSED;
- p->pid = 0;
- p->parent = 0;
- p->name[0] = 0;
- p->killed = 0;
- release(&ptable.lock);
- return pid;
- }
- }
- // No point waiting if we don't have any children.
- if(!havekids || proc->killed){
- release(&ptable.lock);
- return -1;
- }
- // Wait for children to exit. (See wakeup1 call in proc_exit.)
- sleep(proc, &ptable.lock); //DOC: wait-sleep
- }
- }
- // Per-CPU process scheduler.
- // Each CPU calls scheduler() after setting itself up.
- // Scheduler never returns. It loops, doing:
- // - choose a process to run
- // - swtch to start running that process
- // - eventually that process transfers control
- // via swtch back to the scheduler.
- void
- scheduler(void)
- {
- struct proc *p;
- int seed=0;
- for(;;){
- // Enable interrupts on this processor.
- sti();
- seed++;
- // winner = lcg64_temper(seed) % num_tickets;
- winner = lcg_rand(seed) % num_tickets;
- // Loop over process table looking for process to run.
- acquire(&ptable.lock);
- for(p = ptable.proc; p < &ptable.proc[NPROC]; p++){
- if(p->state != RUNNABLE)
- continue;
- // Switch to chosen process. It is the process's job
- // to release ptable.lock and then reacquire it
- // before jumping back to us.
- proc = p;
- switchuvm(p);
- p->state = RUNNING;
- swtch(&cpu->scheduler, proc->context);
- switchkvm();
- // Process is done running for now.
- // It should have changed its p->state before coming back.
- proc = 0;
- }
- release(&ptable.lock);
- }
- }
- // Enter scheduler. Must hold only ptable.lock
- // and have changed proc->state.
- void
- sched(void)
- {
- int intena;
- if(!holding(&ptable.lock))
- panic("sched ptable.lock");
- if(cpu->ncli != 1)
- panic("sched locks");
- if(proc->state == RUNNING)
- panic("sched running");
- if(readeflags()&FL_IF)
- panic("sched interruptible");
- intena = cpu->intena;
- swtch(&proc->context, cpu->scheduler);
- cpu->intena = intena;
- }
- // Give up the CPU for one scheduling round.
- void
- yield(void)
- {
- acquire(&ptable.lock); //DOC: yieldlock
- proc->state = RUNNABLE;
- sched();
- release(&ptable.lock);
- }
- // A fork child's very first scheduling by scheduler()
- // will swtch here. "Return" to user space.
- void
- forkret(void)
- {
- // Still holding ptable.lock from scheduler.
- release(&ptable.lock);
- // Return to "caller", actually trapret (see allocproc).
- }
- // Atomically release lock and sleep on chan.
- // Reacquires lock when awakened.
- void
- sleep(void *chan, struct spinlock *lk)
- {
- if(proc == 0)
- panic("sleep");
- if(lk == 0)
- panic("sleep without lk");
- // Must acquire ptable.lock in order to
- // change p->state and then call sched.
- // Once we hold ptable.lock, we can be
- // guaranteed that we won't miss any wakeup
- // (wakeup runs with ptable.lock locked),
- // so it's okay to release lk.
- if(lk != &ptable.lock){ //DOC: sleeplock0
- acquire(&ptable.lock); //DOC: sleeplock1
- release(lk);
- }
- // Go to sleep.
- proc->chan = chan;
- proc->state = SLEEPING;
- sched();
- // Tidy up.
- proc->chan = 0;
- // Reacquire original lock.
- if(lk != &ptable.lock){ //DOC: sleeplock2
- release(&ptable.lock);
- acquire(lk);
- }
- }
- // Wake up all processes sleeping on chan.
- // The ptable lock must be held.
- static void
- wakeup1(void *chan)
- {
- struct proc *p;
- for(p = ptable.proc; p < &ptable.proc[NPROC]; p++)
- if(p->state == SLEEPING && p->chan == chan)
- p->state = RUNNABLE;
- }
- // Wake up all processes sleeping on chan.
- void
- wakeup(void *chan)
- {
- acquire(&ptable.lock);
- wakeup1(chan);
- release(&ptable.lock);
- }
- // Kill the process with the given pid.
- // Process won't exit until it returns
- // to user space (see trap in trap.c).
- int
- kill(int pid)
- {
- struct proc *p;
- acquire(&ptable.lock);
- for(p = ptable.proc; p < &ptable.proc[NPROC]; p++){
- if(p->pid == pid){
- p->killed = 1;
- // Wake process from sleep if necessary.
- if(p->state == SLEEPING)
- p->state = RUNNABLE;
- release(&ptable.lock);
- return 0;
- }
- }
- release(&ptable.lock);
- return -1;
- }
- // Print a process listing to console. For debugging.
- // Runs when user types ^P on console.
- // No lock to avoid wedging a stuck machine further.
- int
- lottery(int tickets, int pid)
- {
- int i;
- struct proc *p;
- //acquire(&proc_table_lock);
- acquire(&ptable.lock); //mona2
- for(i = 0; i < NPROC; i++){
- p = &proc[i];
- if(p->pid != pid)
- continue;
- if(p->state == UNUSED)
- return -1;
- if(p->state == RUNNING || p->state == RUNNABLE)
- num_tickets += (tickets - p->tickets);
- p->tickets = tickets;
- //release(&proc_table_lock);
- release(&ptable.lock); //mona2
- return 0;
- }
- }
- void
- procdump(void)
- {
- static char *states[] = {
- [UNUSED] "unused",
- [EMBRYO] "embryo",
- [SLEEPING] "sleep ",
- [RUNNABLE] "runble",
- [RUNNING] "run ",
- [ZOMBIE] "zombie"
- };
- int i;
- struct proc *p;
- char *state;
- uint pc[10];
- for(p = ptable.proc; p < &ptable.proc[NPROC]; p++){
- if(p->state == UNUSED)
- continue;
- if(p->state >= 0 && p->state < NELEM(states) && states[p->state])
- state = states[p->state];
- else
- state = "???";
- cprintf("%d %s %s", p->pid, state, p->name);
- if(p->state == SLEEPING){
- getcallerpcs((uint*)p->context->ebp+2, pc);
- for(i=0; i<10 && pc[i] != 0; i++)
- cprintf(" %p", pc[i]);
- } // end if
- cprintf("\n");
- } // end for
- } // you need to add this
Advertisement
Add Comment
Please, Sign In to add comment
Advertisement