- added description of djurban's branch

[packages/kernel.git] / sched-O1-2.4.17-J9.patch

--- linux/fs/proc/proc_misc.c.orig      Sun Jan  6 13:55:55 2002
+++ linux/fs/proc/proc_misc.c   Sun Jan  6 13:56:25 2002
@@ -85,11 +85,11 @@
        a = avenrun[0] + (FIXED_1/200);
        b = avenrun[1] + (FIXED_1/200);
        c = avenrun[2] + (FIXED_1/200);
-       len = sprintf(page,"%d.%02d %d.%02d %d.%02d %d/%d %d\n",
+       len = sprintf(page,"%d.%02d %d.%02d %d.%02d %ld/%d %d\n",
                LOAD_INT(a), LOAD_FRAC(a),
                LOAD_INT(b), LOAD_FRAC(b),
                LOAD_INT(c), LOAD_FRAC(c),
-               nr_running, nr_threads, last_pid);
+               nr_running(), nr_threads, last_pid);
        return proc_calc_metrics(page, start, off, count, eof, len);
 }
 
@@ -101,7 +101,7 @@
        int len;
 
        uptime = jiffies;
-       idle = init_tasks[0]->times.tms_utime + init_tasks[0]->times.tms_stime;
+       idle = init_task.times.tms_utime + init_task.times.tms_stime;
 
        /* The formula for the fraction parts really is ((t * 100) / HZ) % 100, but
           that would overflow about every five days at HZ == 100.
@@ -303,10 +303,10 @@
        }
 
        len += sprintf(page + len,
-               "\nctxt %u\n"
+               "\nctxt %lu\n"
                "btime %lu\n"
                "processes %lu\n",
-               kstat.context_swtch,
+               nr_context_switches(),
                xtime.tv_sec - jif / HZ,
                total_forks);
 
--- linux/fs/proc/array.c.orig  Sun Jan  6 13:55:51 2002
+++ linux/fs/proc/array.c       Mon Jan  7 20:01:05 2002
@@ -335,9 +335,12 @@
 
        /* scale priority and nice values from timeslices to -20..20 */
        /* to make it look like a "normal" Unix priority/nice value  */
-       priority = task->counter;
-       priority = 20 - (priority * 10 + DEF_COUNTER / 2) / DEF_COUNTER;
-       nice = task->nice;
+       priority = task->prio;
+       if (priority >= MAX_RT_PRIO)
+               priority -= MAX_RT_PRIO;
+       else
+               priority = priority-100;
+       nice = task->__nice;
 
        read_lock(&tasklist_lock);
        ppid = task->pid ? task->p_opptr->pid : 0;
@@ -387,7 +390,7 @@
                task->nswap,
                task->cnswap,
                task->exit_signal,
-               task->processor);
+               task->cpu);
        if(mm)
                mmput(mm);
        return res;
--- linux/fs/nfs/pagelist.c.orig        Sun Jan  6 13:55:57 2002
+++ linux/fs/nfs/pagelist.c     Sun Jan  6 13:56:25 2002
@@ -96,8 +96,7 @@
                        continue;
                if (signalled() && (server->flags & NFS_MOUNT_INTR))
                        return ERR_PTR(-ERESTARTSYS);
-               current->policy = SCHED_YIELD;
-               schedule();
+               yield();
        }
 
        /* Initialize the request struct. Initially, we assume a
--- linux/fs/ufs/truncate.c.orig        Sun Jan  6 13:55:55 2002
+++ linux/fs/ufs/truncate.c     Sun Jan  6 13:56:25 2002
@@ -448,10 +448,7 @@
                if (IS_SYNC(inode) && (inode->i_state & I_DIRTY))
                        ufs_sync_inode (inode);
                run_task_queue(&tq_disk);
-               current->policy |= SCHED_YIELD;
-               schedule ();
-
-
+               yield();
        }
        offset = inode->i_size & uspi->s_fshift;
        if (offset) {
--- linux/fs/reiserfs/buffer2.c.orig    Sun Jan  6 13:55:57 2002
+++ linux/fs/reiserfs/buffer2.c Sun Jan  6 13:56:25 2002
@@ -33,8 +33,7 @@
                        buffer_journal_dirty(bh) ? ' ' : '!');
     }
     run_task_queue(&tq_disk);
-    current->policy |= SCHED_YIELD;
-    schedule();
+    yield();
   }
   if (repeat_counter > 30000000) {
     reiserfs_warning("vs-3051: done waiting, ignore vs-3050 messages for (%b)\n", bh) ;
@@ -52,11 +51,11 @@
 struct buffer_head  * reiserfs_bread (struct super_block *super, int n_block, int n_size) 
 {
     struct buffer_head  *result;
-    PROC_EXP( unsigned int ctx_switches = kstat.context_swtch );
+    PROC_EXP( unsigned int ctx_switches = nr_context_switches(); );
 
     result = bread (super -> s_dev, n_block, n_size);
     PROC_INFO_INC( super, breads );
-    PROC_EXP( if( kstat.context_swtch != ctx_switches ) 
+    PROC_EXP( if( nr_context_switches() != ctx_switches ) 
              PROC_INFO_INC( super, bread_miss ) );
     return result;
 }
--- linux/fs/reiserfs/journal.c.orig    Sun Jan  6 13:55:57 2002
+++ linux/fs/reiserfs/journal.c Sun Jan  6 13:56:25 2002
@@ -149,8 +149,7 @@
   }
   bn = allocate_bitmap_node(p_s_sb) ;
   if (!bn) {
-    current->policy |= SCHED_YIELD ;
-    schedule() ;
+    yield();
     goto repeat ;
   }
   return bn ;
--- linux/fs/jffs2/background.c.orig    Sun Jan  6 13:55:53 2002
+++ linux/fs/jffs2/background.c Sun Jan  6 13:56:25 2002
@@ -106,9 +106,6 @@
 
         sprintf(current->comm, "jffs2_gcd_mtd%d", c->mtd->index);
 
-       /* FIXME in the 2.2 backport */
-       current->nice = 10;
-
        for (;;) {
                spin_lock_irq(&current->sigmask_lock);
                siginitsetinv (&current->blocked, sigmask(SIGHUP) | sigmask(SIGKILL) | sigmask(SIGSTOP) | sigmask(SIGCONT));
--- linux/fs/jbd/journal.c.orig Sun Jan  6 13:55:57 2002
+++ linux/fs/jbd/journal.c      Sun Jan  6 13:56:25 2002
@@ -460,8 +460,7 @@
                        printk (KERN_NOTICE __FUNCTION__
                                ": ENOMEM at get_unused_buffer_head, "
                                "trying again.\n");
-                       current->policy |= SCHED_YIELD;
-                       schedule();
+                       yield();
                }
        } while (!new_bh);
        /* keep subsequent assertions sane */
@@ -1539,8 +1538,7 @@
                        last_warning = jiffies;
                }
                
-               current->policy |= SCHED_YIELD;
-               schedule();
+               yield();
        }
 }
 
@@ -1598,8 +1596,7 @@
                        last_warning = jiffies;
                }
                while (ret == 0) {
-                       current->policy |= SCHED_YIELD;
-                       schedule();
+                       yield();
                        ret = kmem_cache_alloc(journal_head_cache, GFP_NOFS);
                }
        }
--- linux/fs/jbd/revoke.c.orig  Sun Jan  6 13:55:57 2002
+++ linux/fs/jbd/revoke.c       Sun Jan  6 13:56:25 2002
@@ -137,8 +137,7 @@
        if (!journal_oom_retry)
                return -ENOMEM;
        jbd_debug(1, "ENOMEM in " __FUNCTION__ ", retrying.\n");
-       current->policy |= SCHED_YIELD;
-       schedule();
+       yield();
        goto repeat;
 }
 
--- linux/fs/jbd/transaction.c.orig     Sun Jan  6 13:55:57 2002
+++ linux/fs/jbd/transaction.c  Sun Jan  6 13:56:25 2002
@@ -1377,8 +1377,7 @@
                do {
                        old_handle_count = transaction->t_handle_count;
                        set_current_state(TASK_RUNNING);
-                       current->policy |= SCHED_YIELD;
-                       schedule();
+                       yield();
                } while (old_handle_count != transaction->t_handle_count);
        }
 
--- linux/fs/binfmt_elf.c.orig  Sun Jan  6 13:55:57 2002
+++ linux/fs/binfmt_elf.c       Sun Jan  6 13:56:25 2002
@@ -1143,7 +1143,7 @@
        psinfo.pr_state = i;
        psinfo.pr_sname = (i < 0 || i > 5) ? '.' : "RSDZTD"[i];
        psinfo.pr_zomb = psinfo.pr_sname == 'Z';
-       psinfo.pr_nice = current->nice;
+       psinfo.pr_nice = current->__nice;
        psinfo.pr_flag = current->flags;
        psinfo.pr_uid = NEW_TO_OLD_UID(current->uid);
        psinfo.pr_gid = NEW_TO_OLD_GID(current->gid);
--- linux/fs/buffer.c.orig      Sun Jan  6 13:55:57 2002
+++ linux/fs/buffer.c   Fri Jan 25 14:25:56 2002
@@ -725,9 +725,8 @@
        wakeup_bdflush();
        try_to_free_pages(zone, GFP_NOFS, 0);
        run_task_queue(&tq_disk);
-       current->policy |= SCHED_YIELD;
        __set_current_state(TASK_RUNNING);
-       schedule();
+       sys_sched_yield();
 }
 
 void init_buffer(struct buffer_head *bh, bh_end_io_t *handler, void *private)
--- linux/fs/locks.c.orig       Sun Jan  6 13:55:51 2002
+++ linux/fs/locks.c    Sun Jan  6 13:56:25 2002
@@ -445,8 +445,7 @@
                        /* Let the blocked process remove waiter from the
                         * block list when it gets scheduled.
                         */
-                       current->policy |= SCHED_YIELD;
-                       schedule();
+                       yield();
                } else {
                        /* Remove waiter from the block list, because by the
                         * time it wakes up blocker won't exist any more.
--- linux/init/main.c.orig      Sun Jan  6 13:55:57 2002
+++ linux/init/main.c   Mon Jan 28 18:12:51 2002
@@ -482,8 +482,6 @@
 extern void setup_arch(char **);
 extern void cpu_idle(void);
 
-unsigned long wait_init_idle;
-
 #ifndef CONFIG_SMP
 
 #ifdef CONFIG_X86_LOCAL_APIC
@@ -492,34 +490,24 @@
        APIC_init_uniprocessor();
 }
 #else
-#define smp_init()     do { } while (0)
+#define smp_init()      do { } while (0)
 #endif
 
 #else
 
-
 /* Called by boot processor to activate the rest. */
 static void __init smp_init(void)
 {
        /* Get other processors into their bootup holding patterns. */
        smp_boot_cpus();
-       wait_init_idle = cpu_online_map;
-       clear_bit(current->processor, &wait_init_idle); /* Don't wait on me! */
 
        smp_threads_ready=1;
        smp_commence();
-
-       /* Wait for the other cpus to set up their idle processes */
-       printk("Waiting on wait_init_idle (map = 0x%lx)\n", wait_init_idle);
-       while (wait_init_idle) {
-               cpu_relax();
-               barrier();
-       }
-       printk("All processors have done init_idle\n");
 }
 
 #endif
 
+
 /*
  * We need to finalize in a non-__init function or else race conditions
  * between the root thread and the init thread may cause start_kernel to
@@ -531,9 +519,8 @@
 {
        kernel_thread(init, NULL, CLONE_FS | CLONE_FILES | CLONE_SIGNAL);
        unlock_kernel();
-       current->need_resched = 1;
-       cpu_idle();
-} 
+       cpu_idle();
+}
 
 /*
  *     Activate the first processor.
@@ -611,14 +598,18 @@
        ipc_init();
 #endif
        check_bugs();
+
        printk("POSIX conformance testing by UNIFIX\n");
 
-       /* 
-        *      We count on the initial thread going ok 
-        *      Like idlers init is an unlocked kernel thread, which will
-        *      make syscalls (and thus be locked).
+       init_idle(current, smp_processor_id());
+       /*
+        *      We count on the initial thread going ok
+        *      Like idlers init is an unlocked kernel thread, which will
+        *      make syscalls (and thus be locked).
         */
        smp_init();
+
+       /* Do the rest non-__init'ed, we're now alive */
        rest_init();
 }
 
@@ -779,12 +770,9 @@
                int i, pid;
 
                pid = kernel_thread(do_linuxrc, "/linuxrc", SIGCHLD);
-               if (pid > 0) {
-                       while (pid != wait(&i)) {
-                               current->policy |= SCHED_YIELD;
-                               schedule();
-                       }
-               }
+               if (pid > 0)
+                       while (pid != wait(&i))
+                               yield();
                if (MAJOR(real_root_dev) != RAMDISK_MAJOR
                     || MINOR(real_root_dev) != 0) {
                        error = change_root(real_root_dev,"/initrd");
--- linux/kernel/sched.c.orig   Sun Jan  6 13:55:57 2002
+++ linux/kernel/sched.c        Mon Jan 28 18:41:54 2002
@@ -12,333 +12,249 @@
  *  1998-12-28  Implemented better SMP scheduling by Ingo Molnar
  */
 
-/*
- * 'sched.c' is the main kernel file. It contains scheduling primitives
- * (sleep_on, wakeup, schedule etc) as well as a number of simple system
- * call functions (type getpid()), which just extract a field from
- * current-task
- */
-
-#include <linux/config.h>
 #include <linux/mm.h>
+#include <linux/nmi.h>
 #include <linux/init.h>
+#include <asm/uaccess.h>
 #include <linux/smp_lock.h>
-#include <linux/nmi.h>
 #include <linux/interrupt.h>
-#include <linux/kernel_stat.h>
-#include <linux/completion.h>
-#include <linux/prefetch.h>
-#include <linux/compiler.h>
-
-#include <asm/uaccess.h>
 #include <asm/mmu_context.h>
 
-extern void timer_bh(void);
-extern void tqueue_bh(void);
-extern void immediate_bh(void);
-
-/*
- * scheduler variables
- */
+#define BITMAP_SIZE ((((MAX_PRIO+7)/8)+sizeof(long)-1)/sizeof(long))
 
-unsigned securebits = SECUREBITS_DEFAULT; /* systemwide security settings */
+typedef struct runqueue runqueue_t;
 
-extern void mem_use(void);
+struct prio_array {
+       int nr_active;
+       spinlock_t *lock;
+       runqueue_t *rq;
+       unsigned long bitmap[BITMAP_SIZE];
+       list_t queue[MAX_PRIO];
+};
 
 /*
- * Scheduling quanta.
+ * This is the main, per-CPU runqueue data structure.
  *
- * NOTE! The unix "nice" value influences how long a process
- * gets. The nice value ranges from -20 to +19, where a -20
- * is a "high-priority" task, and a "+10" is a low-priority
- * task.
- *
- * We want the time-slice to be around 50ms or so, so this
- * calculation depends on the value of HZ.
+ * Locking rule: those places that want to lock multiple runqueues
+ * (such as the load balancing or the process migration code), lock
+ * acquire operations must be ordered by ascending &runqueue.
  */
-#if HZ < 200
-#define TICK_SCALE(x)  ((x) >> 2)
-#elif HZ < 400
-#define TICK_SCALE(x)  ((x) >> 1)
-#elif HZ < 800
-#define TICK_SCALE(x)  (x)
-#elif HZ < 1600
-#define TICK_SCALE(x)  ((x) << 1)
-#else
-#define TICK_SCALE(x)  ((x) << 2)
-#endif
+struct runqueue {
+       spinlock_t lock;
+       unsigned long nr_running, nr_switches, expired_timestamp;
+       task_t *curr, *idle;
+       prio_array_t *active, *expired, arrays[2];
+       int prev_nr_running[NR_CPUS];
+} ____cacheline_aligned;
 
-#define NICE_TO_TICKS(nice)    (TICK_SCALE(20-(nice))+1)
+static struct runqueue runqueues[NR_CPUS] __cacheline_aligned;
 
+#define cpu_rq(cpu)            (runqueues + (cpu))
+#define this_rq()              cpu_rq(smp_processor_id())
+#define task_rq(p)             cpu_rq((p)->cpu)
+#define cpu_curr(cpu)          (cpu_rq(cpu)->curr)
+#define rt_task(p)             ((p)->policy != SCHED_OTHER)
+
+
+static inline runqueue_t *lock_task_rq(task_t *p, unsigned long *flags)
+{
+       struct runqueue *__rq;
+
+repeat_lock_task:
+       __rq = task_rq(p);
+       spin_lock_irqsave(&__rq->lock, *flags);
+       if (unlikely(__rq != task_rq(p))) {
+               spin_unlock_irqrestore(&__rq->lock, *flags);
+               goto repeat_lock_task;
+       }
+       return __rq;
+}
 
+static inline void unlock_task_rq(runqueue_t *rq, unsigned long *flags)
+{
+       spin_unlock_irqrestore(&rq->lock, *flags);
+}
 /*
- *     Init task must be ok at boot for the ix86 as we will check its signals
- *     via the SMP irq return path.
+ * Adding/removing a task to/from a priority array:
  */
- 
-struct task_struct * init_tasks[NR_CPUS] = {&init_task, };
+static inline void dequeue_task(struct task_struct *p, prio_array_t *array)
+{
+       array->nr_active--;
+       list_del_init(&p->run_list);
+       if (list_empty(array->queue + p->prio))
+               __clear_bit(p->prio, array->bitmap);
+}
+
+static inline void enqueue_task(struct task_struct *p, prio_array_t *array)
+{
+       list_add_tail(&p->run_list, array->queue + p->prio);
+       __set_bit(p->prio, array->bitmap);
+       array->nr_active++;
+       p->array = array;
+}
 
 /*
- * The tasklist_lock protects the linked list of processes.
+ * A task is 'heavily interactive' if it either has reached the
+ * bottom 25% of the SCHED_OTHER priority range, or if it is below
+ * its default priority by at least 3 priority levels. In this
+ * case we favor it by reinserting it on the active array,
+ * even after it expired its current timeslice.
  *
- * The runqueue_lock locks the parts that actually access
- * and change the run-queues, and have to be interrupt-safe.
+ * A task is a 'CPU hog' if it's either in the upper 25% of the
+ * SCHED_OTHER priority range, or if's not an interactive task.
  *
- * If both locks are to be concurrently held, the runqueue_lock
- * nests inside the tasklist_lock.
+ * A task can get a priority bonus by being 'somewhat
+ * interactive' - and it will get a priority penalty for
+ * being a CPU hog.
  *
- * task->alloc_lock nests inside tasklist_lock.
- */
-spinlock_t runqueue_lock __cacheline_aligned = SPIN_LOCK_UNLOCKED;  /* inner */
-rwlock_t tasklist_lock __cacheline_aligned = RW_LOCK_UNLOCKED; /* outer */
-
-static LIST_HEAD(runqueue_head);
-
-/*
- * We align per-CPU scheduling data on cacheline boundaries,
- * to prevent cacheline ping-pong.
  */
-static union {
-       struct schedule_data {
-               struct task_struct * curr;
-               cycles_t last_schedule;
-       } schedule_data;
-       char __pad [SMP_CACHE_BYTES];
-} aligned_data [NR_CPUS] __cacheline_aligned = { {{&init_task,0}}};
-
-#define cpu_curr(cpu) aligned_data[(cpu)].schedule_data.curr
-#define last_schedule(cpu) aligned_data[(cpu)].schedule_data.last_schedule
-
-struct kernel_stat kstat;
-extern struct task_struct *child_reaper;
-
-#ifdef CONFIG_SMP
-
-#define idle_task(cpu) (init_tasks[cpu_number_map(cpu)])
-#define can_schedule(p,cpu) \
-       ((p)->cpus_runnable & (p)->cpus_allowed & (1 << cpu))
-
-#else
-
-#define idle_task(cpu) (&init_task)
-#define can_schedule(p,cpu) (1)
-
-#endif
 
-void scheduling_functions_start_here(void) { }
+#define PRIO_INTERACTIVE \
+               (MAX_RT_PRIO + MAX_USER_PRIO*PRIO_INTERACTIVE_RATIO/100)
+#define PRIO_CPU_HOG \
+               (MAX_RT_PRIO + MAX_USER_PRIO*PRIO_CPU_HOG_RATIO/100)
+
+#define TASK_INTERACTIVE(p) \
+       (((p)->prio <= PRIO_INTERACTIVE) || \
+       (((p)->prio < PRIO_CPU_HOG) && \
+               ((p)->prio <= NICE_TO_PRIO((p)->__nice) - INTERACTIVE_DELTA)))
 
 /*
- * This is the function that decides how desirable a process is..
- * You can weigh different processes against each other depending
- * on what CPU they've run on lately etc to try to handle cache
- * and TLB miss penalties.
+ * We place interactive tasks back into the active array, if possible.
  *
- * Return values:
- *      -1000: never select this
- *          0: out of time, recalculate counters (but it might still be
- *             selected)
- *        +ve: "goodness" value (the larger, the better)
- *      +1000: realtime process, select this.
+ * To guarantee that this does not starve expired tasks we ignore the
+ * interactivity of a task if the first expired task had to wait more
+ * than a 'reasonable' amount of time. This deadline timeout is
+ * load-dependent, as the frequency of array switched decreases with
+ * increasing number of running tasks:
  */
+#define EXPIRED_STARVING(rq) \
+               ((rq)->expired_timestamp && \
+               (jiffies - (rq)->expired_timestamp >= \
+                       STARVATION_LIMIT * ((rq)->nr_running) + 1))
 
-static inline int goodness(struct task_struct * p, int this_cpu, struct mm_struct *this_mm)
+static inline int effective_prio(task_t *p)
 {
-       int weight;
+       int bonus, prio;
 
        /*
-        * select the current process after every other
-        * runnable process, but before the idle thread.
-        * Also, dont trigger a counter recalculation.
+        * Here we scale the actual sleep average [0 .... MAX_SLEEP_AVG]
+        * into the -14 ... +14 bonus/penalty range.
+        *
+        * We use 70% of the full 0...39 priority range so that:
+        *
+        * 1) nice +19 CPU hogs do not preempt nice 0 CPU hogs.
+        * 2) nice -20 interactive tasks do not get preempted by
+        *    nice 0 interactive tasks.
+        *
+        * Both properties are important to certain workloads.
         */
-       weight = -1;
-       if (p->policy & SCHED_YIELD)
-               goto out;
+       bonus = MAX_USER_PRIO*PRIO_BONUS_RATIO*p->sleep_avg/MAX_SLEEP_AVG/100 -
+                       MAX_USER_PRIO*PRIO_BONUS_RATIO/100/2;
 
-       /*
-        * Non-RT process - normal case first.
-        */
-       if (p->policy == SCHED_OTHER) {
+       prio = NICE_TO_PRIO(p->__nice) - bonus;
+       if (prio < MAX_RT_PRIO)
+               prio = MAX_RT_PRIO;
+       if (prio > MAX_PRIO-1)
+               prio = MAX_PRIO-1;
+       return prio;
+}
+
+static inline void activate_task(task_t *p, runqueue_t *rq)
+{
+       unsigned long sleep_time = jiffies - p->sleep_timestamp;
+       prio_array_t *array = rq->active;
+
+       if (!rt_task(p) && sleep_time) {
                /*
-                * Give the process a first-approximation goodness value
-                * according to the number of clock-ticks it has left.
-                *
-                * Don't do any other calculations if the time slice is
-                * over..
+                * This code gives a bonus to interactive tasks. We update
+                * an 'average sleep time' value here, based on
+                * sleep_timestamp. The more time a task spends sleeping,
+                * the higher the average gets - and the higher the priority
+                * boost gets as well.
                 */
-               weight = p->counter;
-               if (!weight)
-                       goto out;
-                       
-#ifdef CONFIG_SMP
-               /* Give a largish advantage to the same processor...   */
-               /* (this is equivalent to penalizing other processors) */
-               if (p->processor == this_cpu)
-                       weight += PROC_CHANGE_PENALTY;
-#endif
-
-               /* .. and a slight advantage to the current MM */
-               if (p->mm == this_mm || !p->mm)
-                       weight += 1;
-               weight += 20 - p->nice;
-               goto out;
+               p->sleep_avg += sleep_time;
+               if (p->sleep_avg > MAX_SLEEP_AVG)
+                       p->sleep_avg = MAX_SLEEP_AVG;
+               p->prio = effective_prio(p);
        }
+       enqueue_task(p, array);
+       rq->nr_running++;
+}
 
-       /*
-        * Realtime process, select the first one on the
-        * runqueue (taking priorities within processes
-        * into account).
-        */
-       weight = 1000 + p->rt_priority;
-out:
-       return weight;
+static inline void deactivate_task(struct task_struct *p, runqueue_t *rq)
+{
+       rq->nr_running--;
+       dequeue_task(p, p->array);
+       p->array = NULL;
+       p->sleep_timestamp = jiffies;
 }
 
-/*
- * the 'goodness value' of replacing a process on a given CPU.
- * positive value means 'replace', zero or negative means 'dont'.
- */
-static inline int preemption_goodness(struct task_struct * prev, struct task_struct * p, int cpu)
+static inline void resched_task(task_t *p)
 {
-       return goodness(p, cpu, prev->active_mm) - goodness(prev, cpu, prev->active_mm);
+       int need_resched;
+
+       need_resched = p->need_resched;
+       wmb();
+       p->need_resched = 1;
+       if (!need_resched && (p->cpu != smp_processor_id()))
+               smp_send_reschedule(p->cpu);
 }
 
+#ifdef CONFIG_SMP
+
 /*
- * This is ugly, but reschedule_idle() is very timing-critical.
- * We are called with the runqueue spinlock held and we must
- * not claim the tasklist_lock.
+ * Wait for a process to unschedule. This is used by the exit() and
+ * ptrace() code.
  */
-static FASTCALL(void reschedule_idle(struct task_struct * p));
-
-static void reschedule_idle(struct task_struct * p)
+void wait_task_inactive(task_t * p)
 {
-#ifdef CONFIG_SMP
-       int this_cpu = smp_processor_id();
-       struct task_struct *tsk, *target_tsk;
-       int cpu, best_cpu, i, max_prio;
-       cycles_t oldest_idle;
+       unsigned long flags;
+       runqueue_t *rq;
 
-       /*
-        * shortcut if the woken up task's last CPU is
-        * idle now.
-        */
-       best_cpu = p->processor;
-       if (can_schedule(p, best_cpu)) {
-               tsk = idle_task(best_cpu);
-               if (cpu_curr(best_cpu) == tsk) {
-                       int need_resched;
-send_now_idle:
-                       /*
-                        * If need_resched == -1 then we can skip sending
-                        * the IPI altogether, tsk->need_resched is
-                        * actively watched by the idle thread.
-                        */
-                       need_resched = tsk->need_resched;
-                       tsk->need_resched = 1;
-                       if ((best_cpu != this_cpu) && !need_resched)
-                               smp_send_reschedule(best_cpu);
-                       return;
-               }
+repeat:
+       rq = task_rq(p);
+       while (unlikely(rq->curr == p)) {
+               cpu_relax();
+               barrier();
+       }
+       rq = lock_task_rq(p, &flags);
+       if (unlikely(rq->curr == p)) {
+               unlock_task_rq(rq, &flags);
+               goto repeat;
        }
-
-       /*
-        * We know that the preferred CPU has a cache-affine current
-        * process, lets try to find a new idle CPU for the woken-up
-        * process. Select the least recently active idle CPU. (that
-        * one will have the least active cache context.) Also find
-        * the executing process which has the least priority.
-        */
-       oldest_idle = (cycles_t) -1;
-       target_tsk = NULL;
-       max_prio = 0;
-
-       for (i = 0; i < smp_num_cpus; i++) {
-               cpu = cpu_logical_map(i);
-               if (!can_schedule(p, cpu))
-                       continue;
-               tsk = cpu_curr(cpu);
-               /*
-                * We use the first available idle CPU. This creates
-                * a priority list between idle CPUs, but this is not
-                * a problem.
-                */
-               if (tsk == idle_task(cpu)) {
-#if defined(__i386__) && defined(CONFIG_SMP)
-                        /*
-                        * Check if two siblings are idle in the same
-                        * physical package. Use them if found.
-                        */
-                       if (smp_num_siblings == 2) {
-                               if (cpu_curr(cpu_sibling_map[cpu]) == 
-                                   idle_task(cpu_sibling_map[cpu])) {
-                                       oldest_idle = last_schedule(cpu);
-                                       target_tsk = tsk;
-                                       break;
-                               }
-                               
-                        }
-#endif         
-                       if (last_schedule(cpu) < oldest_idle) {
-                               oldest_idle = last_schedule(cpu);
-                               target_tsk = tsk;
-                       }
-               } else {
-                       if (oldest_idle == -1ULL) {
-                               int prio = preemption_goodness(tsk, p, cpu);
-
-                               if (prio > max_prio) {
-                                       max_prio = prio;
-                                       target_tsk = tsk;
-                               }
-                       }
-               }
-       }
-       tsk = target_tsk;
-       if (tsk) {
-               if (oldest_idle != -1ULL) {
-                       best_cpu = tsk->processor;
-                       goto send_now_idle;
-               }
-               tsk->need_resched = 1;
-               if (tsk->processor != this_cpu)
-                       smp_send_reschedule(tsk->processor);
-       }
-       return;
-               
-
-#else /* UP */
-       int this_cpu = smp_processor_id();
-       struct task_struct *tsk;
-
-       tsk = cpu_curr(this_cpu);
-       if (preemption_goodness(tsk, p, this_cpu) > 0)
-               tsk->need_resched = 1;
-#endif
+       unlock_task_rq(rq, &flags);
 }
 
 /*
- * Careful!
+ * The SMP message passing code calls this function whenever
+ * the new task has arrived at the target CPU. We move the
+ * new task into the local runqueue.
  *
- * This has to add the process to the _beginning_ of the
- * run-queue, not the end. See the comment about "This is
- * subtle" in the scheduler proper..
+ * This function must be called with interrupts disabled.
  */
-static inline void add_to_runqueue(struct task_struct * p)
+void sched_task_migrated(task_t *new_task)
 {
-       list_add(&p->run_list, &runqueue_head);
-       nr_running++;
+       wait_task_inactive(new_task);
+       new_task->cpu = smp_processor_id();
+       wake_up_process(new_task);
 }
 
-static inline void move_last_runqueue(struct task_struct * p)
-{
-       list_del(&p->run_list);
-       list_add_tail(&p->run_list, &runqueue_head);
-}
-
-static inline void move_first_runqueue(struct task_struct * p)
+/*
+ * Kick the remote CPU if the task is running currently,
+ * this code is used by the signal code to signal tasks
+ * which are in user-mode as quickly as possible.
+ *
+ * (Note that we do this lockless - if the task does anything
+ * while the message is in flight then it will notice the
+ * sigpending condition anyway.)
+ */
+void kick_if_running(task_t * p)
 {
-       list_del(&p->run_list);
-       list_add(&p->run_list, &runqueue_head);
+       if (p == task_rq(p)->curr)
+               resched_task(p);
 }
+#endif
 
 /*
  * Wake up a process. Put it on the run-queue if it's not
@@ -348,392 +264,472 @@
  * "current->state = TASK_RUNNING" to mark yourself runnable
  * without the overhead of this.
  */
-static inline int try_to_wake_up(struct task_struct * p, int synchronous)
+static int try_to_wake_up(task_t * p, int synchronous)
 {
        unsigned long flags;
        int success = 0;
+       runqueue_t *rq;
 
-       /*
-        * We want the common case fall through straight, thus the goto.
-        */
-       spin_lock_irqsave(&runqueue_lock, flags);
+       rq = lock_task_rq(p, &flags);
        p->state = TASK_RUNNING;
-       if (task_on_runqueue(p))
-               goto out;
-       add_to_runqueue(p);
-       if (!synchronous || !(p->cpus_allowed & (1 << smp_processor_id())))
-               reschedule_idle(p);
-       success = 1;
-out:
-       spin_unlock_irqrestore(&runqueue_lock, flags);
+       if (!p->array) {
+               activate_task(p, rq);
+               if ((rq->curr == rq->idle) || (p->prio < rq->curr->prio))
+                       resched_task(rq->curr);
+               success = 1;
+       }
+       unlock_task_rq(rq, &flags);
        return success;
 }
 
-inline int wake_up_process(struct task_struct * p)
+int wake_up_process(task_t * p)
 {
        return try_to_wake_up(p, 0);
 }
 
-static void process_timeout(unsigned long __data)
+void wake_up_forked_process(task_t * p)
 {
-       struct task_struct * p = (struct task_struct *) __data;
+       runqueue_t *rq = this_rq();
 
-       wake_up_process(p);
+       p->state = TASK_RUNNING;
+       if (!rt_task(p)) {
+               current->sleep_avg = current->sleep_avg * PARENT_FORK_PENALTY / 100;
+               p->sleep_avg = p->sleep_avg * CHILD_FORK_PENALTY / 100;
+               p->prio = effective_prio(p);
+       }
+       spin_lock_irq(&rq->lock);
+       p->cpu = smp_processor_id();
+       activate_task(p, rq);
+       spin_unlock_irq(&rq->lock);
 }
 
-/**
- * schedule_timeout - sleep until timeout
- * @timeout: timeout value in jiffies
- *
- * Make the current task sleep until @timeout jiffies have
- * elapsed. The routine will return immediately unless
- * the current task state has been set (see set_current_state()).
- *
- * You can set the task state as follows -
- *
- * %TASK_UNINTERRUPTIBLE - at least @timeout jiffies are guaranteed to
- * pass before the routine returns. The routine will return 0
- *
- * %TASK_INTERRUPTIBLE - the routine may return early if a signal is
- * delivered to the current task. In this case the remaining time
- * in jiffies will be returned, or 0 if the timer expired in time
- *
- * The current task state is guaranteed to be TASK_RUNNING when this 
- * routine returns.
- *
- * Specifying a @timeout value of %MAX_SCHEDULE_TIMEOUT will schedule
- * the CPU away without a bound on the timeout. In this case the return
- * value will be %MAX_SCHEDULE_TIMEOUT.
- *
- * In all cases the return value is guaranteed to be non-negative.
- */
-signed long schedule_timeout(signed long timeout)
+asmlinkage void schedule_tail(task_t *prev)
 {
-       struct timer_list timer;
-       unsigned long expire;
-
-       switch (timeout)
-       {
-       case MAX_SCHEDULE_TIMEOUT:
-               /*
-                * These two special cases are useful to be comfortable
-                * in the caller. Nothing more. We could take
-                * MAX_SCHEDULE_TIMEOUT from one of the negative value
-                * but I' d like to return a valid offset (>=0) to allow
-                * the caller to do everything it want with the retval.
-                */
-               schedule();
-               goto out;
-       default:
-               /*
-                * Another bit of PARANOID. Note that the retval will be
-                * 0 since no piece of kernel is supposed to do a check
-                * for a negative retval of schedule_timeout() (since it
-                * should never happens anyway). You just have the printk()
-                * that will tell you if something is gone wrong and where.
-                */
-               if (timeout < 0)
-               {
-                       printk(KERN_ERR "schedule_timeout: wrong timeout "
-                              "value %lx from %p\n", timeout,
-                              __builtin_return_address(0));
-                       current->state = TASK_RUNNING;
-                       goto out;
-               }
-       }
+       spin_unlock_irq(&this_rq()->lock);
+}
 
-       expire = timeout + jiffies;
+static inline void context_switch(task_t *prev, task_t *next)
+{
+       struct mm_struct *mm = next->mm;
+       struct mm_struct *oldmm = prev->active_mm;
 
-       init_timer(&timer);
-       timer.expires = expire;
-       timer.data = (unsigned long) current;
-       timer.function = process_timeout;
+       prepare_to_switch();
 
-       add_timer(&timer);
-       schedule();
-       del_timer_sync(&timer);
+       if (unlikely(!mm)) {
+               next->active_mm = oldmm;
+               atomic_inc(&oldmm->mm_count);
+               enter_lazy_tlb(oldmm, next, smp_processor_id());
+       } else
+               switch_mm(oldmm, mm, next, smp_processor_id());
 
-       timeout = expire - jiffies;
+       if (unlikely(!prev->mm)) {
+               prev->active_mm = NULL;
+               mmdrop(oldmm);
+       }
 
- out:
-       return timeout < 0 ? 0 : timeout;
+       /*
+        * Here we just switch the register state and the stack. There are
+        * 3 processes affected by a context switch:
+        *
+        * prev ==> .... ==> (last => next)
+        *
+        * It's the 'much more previous' 'prev' that is on next's stack,
+        * but prev is set to (the just run) 'last' process by switch_to().
+        * This might sound slightly confusing but makes tons of sense.
+        */
+       switch_to(prev, next, prev);
 }
 
-/*
- * schedule_tail() is getting called from the fork return path. This
- * cleans up all remaining scheduler things, without impacting the
- * common case.
- */
-static inline void __schedule_tail(struct task_struct *prev)
+unsigned long nr_running(void)
 {
-#ifdef CONFIG_SMP
-       int policy;
-
-       /*
-        * prev->policy can be written from here only before `prev'
-        * can be scheduled (before setting prev->cpus_runnable to ~0UL).
-        * Of course it must also be read before allowing prev
-        * to be rescheduled, but since the write depends on the read
-        * to complete, wmb() is enough. (the spin_lock() acquired
-        * before setting cpus_runnable is not enough because the spin_lock()
-        * common code semantics allows code outside the critical section
-        * to enter inside the critical section)
-        */
-       policy = prev->policy;
-       prev->policy = policy & ~SCHED_YIELD;
-       wmb();
+       unsigned long i, sum = 0;
 
-       /*
-        * fast path falls through. We have to clear cpus_runnable before
-        * checking prev->state to avoid a wakeup race. Protect against
-        * the task exiting early.
-        */
-       task_lock(prev);
-       task_release_cpu(prev);
-       mb();
-       if (prev->state == TASK_RUNNING)
-               goto needs_resched;
+       for (i = 0; i < smp_num_cpus; i++)
+               sum += cpu_rq(cpu_logical_map(i))->nr_running;
 
-out_unlock:
-       task_unlock(prev);      /* Synchronise here with release_task() if prev is TASK_ZOMBIE */
-       return;
+       return sum;
+}
 
-       /*
-        * Slow path - we 'push' the previous process and
-        * reschedule_idle() will attempt to find a new
-        * processor for it. (but it might preempt the
-        * current process as well.) We must take the runqueue
-        * lock and re-check prev->state to be correct. It might
-        * still happen that this process has a preemption
-        * 'in progress' already - but this is not a problem and
-        * might happen in other circumstances as well.
-        */
-needs_resched:
-       {
-               unsigned long flags;
+unsigned long nr_context_switches(void)
+{
+       unsigned long i, sum = 0;
 
-               /*
-                * Avoid taking the runqueue lock in cases where
-                * no preemption-check is necessery:
-                */
-               if ((prev == idle_task(smp_processor_id())) ||
-                                               (policy & SCHED_YIELD))
-                       goto out_unlock;
+       for (i = 0; i < smp_num_cpus; i++)
+               sum += cpu_rq(cpu_logical_map(i))->nr_switches;
 
-               spin_lock_irqsave(&runqueue_lock, flags);
-               if ((prev->state == TASK_RUNNING) && !task_has_cpu(prev))
-                       reschedule_idle(prev);
-               spin_unlock_irqrestore(&runqueue_lock, flags);
-               goto out_unlock;
-       }
-#else
-       prev->policy &= ~SCHED_YIELD;
-#endif /* CONFIG_SMP */
+       return sum;
 }
 
-asmlinkage void schedule_tail(struct task_struct *prev)
+#if CONFIG_SMP
+/*
+ * Lock the busiest runqueue as well, this_rq is locked already.
+ * Recalculate nr_running if we have to drop the runqueue lock.
+ */
+static inline unsigned int double_lock_balance(runqueue_t *this_rq,
+       runqueue_t *busiest, int this_cpu, int idle, unsigned int nr_running)
 {
-       __schedule_tail(prev);
+       if (unlikely(!spin_trylock(&busiest->lock))) {
+               if (busiest < this_rq) {
+                       spin_unlock(&this_rq->lock);
+                       spin_lock(&busiest->lock);
+                       spin_lock(&this_rq->lock);
+                       /* Need to recalculate nr_running */
+                       if (idle || (this_rq->nr_running > this_rq->prev_nr_running[this_cpu]))
+                               nr_running = this_rq->nr_running;
+                       else
+                               nr_running = this_rq->prev_nr_running[this_cpu];
+               } else
+                       spin_lock(&busiest->lock);
+       }
+       return nr_running;
 }
 
 /*
- *  'schedule()' is the scheduler function. It's a very simple and nice
- * scheduler: it's not perfect, but certainly works for most things.
- *
- * The goto is "interesting".
+ * Current runqueue is empty, or rebalance tick: if there is an
+ * inbalance (current runqueue is too short) then pull from
+ * busiest runqueue(s).
  *
- *   NOTE!!  Task 0 is the 'idle' task, which gets called when no other
- * tasks can run. It can not be killed, and it cannot sleep. The 'state'
- * information in task[0] is never used.
+ * We call this with the current runqueue locked,
+ * irqs disabled.
  */
-asmlinkage void schedule(void)
+static void load_balance(runqueue_t *this_rq, int idle)
 {
-       struct schedule_data * sched_data;
-       struct task_struct *prev, *next, *p;
-       struct list_head *tmp;
-       int this_cpu, c;
+       int imbalance, nr_running, load, max_load,
+               idx, i, this_cpu = smp_processor_id();
+       task_t *next = this_rq->idle, *tmp;
+       runqueue_t *busiest, *rq_src;
+       prio_array_t *array;
+       list_t *head, *curr;
 
+       /*
+        * We search all runqueues to find the most busy one.
+        * We do this lockless to reduce cache-bouncing overhead,
+        * we re-check the 'best' source CPU later on again, with
+        * the lock held.
+        *
+        * We fend off statistical fluctuations in runqueue lengths by
+        * saving the runqueue length during the previous load-balancing
+        * operation and using the smaller one the current and saved lengths.
+        * If a runqueue is long enough for a longer amount of time then
+        * we recognize it and pull tasks from it.
+        *
+        * The 'current runqueue length' is a statistical maximum variable,
+        * for that one we take the longer one - to avoid fluctuations in
+        * the other direction. So for a load-balance to happen it needs
+        * stable long runqueue on the target CPU and stable short runqueue
+        * on the local runqueue.
+        *
+        * We make an exception if this CPU is about to become idle - in
+        * that case we are less picky about moving a task across CPUs and
+        * take what can be taken.
+        */
+       if (idle || (this_rq->nr_running > this_rq->prev_nr_running[this_cpu]))
+               nr_running = this_rq->nr_running;
+       else
+               nr_running = this_rq->prev_nr_running[this_cpu];
 
-       spin_lock_prefetch(&runqueue_lock);
+       busiest = NULL;
+       max_load = 1;
+       for (i = 0; i < smp_num_cpus; i++) {
+               rq_src = cpu_rq(cpu_logical_map(i));
+               if (idle || (rq_src->nr_running < this_rq->prev_nr_running[i]))
+                       load = rq_src->nr_running;
+               else
+                       load = this_rq->prev_nr_running[i];
+               this_rq->prev_nr_running[i] = rq_src->nr_running;
+
+               if ((load > max_load) && (rq_src != this_rq)) {
+                       busiest = rq_src;
+                       max_load = load;
+               }
+       }
 
-       if (!current->active_mm) BUG();
-need_resched_back:
-       prev = current;
-       this_cpu = prev->processor;
+       if (likely(!busiest))
+               return;
 
-       if (unlikely(in_interrupt())) {
-               printk("Scheduling in interrupt\n");
-               BUG();
-       }
+       imbalance = (max_load - nr_running) / 2;
 
-       release_kernel_lock(prev, this_cpu);
+       /* It needs an at least ~25% imbalance to trigger balancing. */
+       if (!idle && (imbalance < (max_load + 3)/4))
+               return;
 
+       nr_running = double_lock_balance(this_rq, busiest, this_cpu, idle, nr_running);
        /*
-        * 'sched_data' is protected by the fact that we can run
-        * only one process per CPU.
+        * Make sure nothing changed since we checked the
+        * runqueue length.
         */
-       sched_data = & aligned_data[this_cpu].schedule_data;
-
-       spin_lock_irq(&runqueue_lock);
-
-       /* move an exhausted RR process to be last.. */
-       if (unlikely(prev->policy == SCHED_RR))
-               if (!prev->counter) {
-                       prev->counter = NICE_TO_TICKS(prev->nice);
-                       move_last_runqueue(prev);
-               }
-
-       switch (prev->state) {
-               case TASK_INTERRUPTIBLE:
-                       if (signal_pending(prev)) {
-                               prev->state = TASK_RUNNING;
-                               break;
-                       }
-               default:
-                       del_from_runqueue(prev);
-               case TASK_RUNNING:;
-       }
-       prev->need_resched = 0;
+       if (busiest->nr_running <= this_rq->nr_running + 1)
+               goto out_unlock;
 
        /*
-        * this is the scheduler proper:
+        * We first consider expired tasks. Those will likely not be
+        * executed in the near future, and they are most likely to
+        * be cache-cold, thus switching CPUs has the least effect
+        * on them.
         */
+       if (busiest->expired->nr_active)
+               array = busiest->expired;
+       else
+               array = busiest->active;
 
-repeat_schedule:
+new_array:
        /*
-        * Default process to select..
+        * Load-balancing does not affect RT tasks, so we start the
+        * searching at priority 128.
         */
-       next = idle_task(this_cpu);
-       c = -1000;
-       list_for_each(tmp, &runqueue_head) {
-               p = list_entry(tmp, struct task_struct, run_list);
-               if (can_schedule(p, this_cpu)) {
-                       int weight = goodness(p, this_cpu, prev->active_mm);
-                       if (weight > c)
-                               c = weight, next = p;
+       idx = MAX_RT_PRIO;
+skip_bitmap:
+       idx = find_next_bit(array->bitmap, MAX_PRIO, idx);
+       if (idx == MAX_PRIO) {
+               if (array == busiest->expired) {
+                       array = busiest->active;
+                       goto new_array;
                }
+               goto out_unlock;
        }
 
-       /* Do we need to re-calculate counters? */
-       if (unlikely(!c)) {
-               struct task_struct *p;
-
-               spin_unlock_irq(&runqueue_lock);
-               read_lock(&tasklist_lock);
-               for_each_task(p)
-                       p->counter = (p->counter >> 1) + NICE_TO_TICKS(p->nice);
-               read_unlock(&tasklist_lock);
-               spin_lock_irq(&runqueue_lock);
-               goto repeat_schedule;
+       head = array->queue + idx;
+       curr = head->prev;
+skip_queue:
+       tmp = list_entry(curr, task_t, run_list);
+
+       /*
+        * We do not migrate tasks that are:
+        * 1) running (obviously), or
+        * 2) cannot be migrated to this CPU due to cpus_allowed, or
+        * 3) are cache-hot on their current CPU.
+        */
+
+#define CAN_MIGRATE_TASK(p,rq,this_cpu)                                        \
+       ((jiffies - (p)->sleep_timestamp > cache_decay_ticks) &&        \
+               ((p) != (rq)->curr) &&                                  \
+                       (tmp->cpus_allowed & (1 << (this_cpu))))
+
+       if (!CAN_MIGRATE_TASK(tmp, busiest, this_cpu)) {
+               curr = curr->next;
+               if (curr != head)
+                       goto skip_queue;
+               idx++;
+               goto skip_bitmap;
+       }
+       next = tmp;
+       /*
+        * take the task out of the other runqueue and
+        * put it into this one:
+        */
+       dequeue_task(next, array);
+       busiest->nr_running--;
+       next->cpu = this_cpu;
+       this_rq->nr_running++;
+       enqueue_task(next, this_rq->active);
+       if (next->prio < current->prio)
+               current->need_resched = 1;
+       if (!idle && --imbalance) {
+               if (array == busiest->expired) {
+                       array = busiest->active;
+                       goto new_array;
+               }
        }
+out_unlock:
+       spin_unlock(&busiest->lock);
+}
+
+/*
+ * One of the idle_cpu_tick() or the busy_cpu_tick() function will
+ * gets called every timer tick, on every CPU. Our balancing action
+ * frequency and balancing agressivity depends on whether the CPU is
+ * idle or not.
+ *
+ * busy-rebalance every 250 msecs. idle-rebalance every 1 msec. (or on
+ * systems with HZ=100, every 10 msecs.)
+ */
+#define BUSY_REBALANCE_TICK (HZ/4 ?: 1)
+#define IDLE_REBALANCE_TICK (HZ/1000 ?: 1)
+
+static inline void idle_tick(void)
+{
+       if (jiffies % IDLE_REBALANCE_TICK)
+               return;
+       spin_lock(&this_rq()->lock);
+       load_balance(this_rq(), 1);
+       spin_unlock(&this_rq()->lock);
+}
+
+#endif
+
+/*
+ * This function gets called by the timer code, with HZ frequency.
+ * We call it with interrupts disabled.
+ */
+void scheduler_tick(task_t *p)
+{
+       runqueue_t *rq = this_rq();
+#if CONFIG_SMP
+       unsigned long now = jiffies;
 
+       if (p == rq->idle)
+               return idle_tick();
+#endif
+       /* Task might have expired already, but not scheduled off yet */
+       if (p->array != rq->active) {
+               p->need_resched = 1;
+               return;
+       }
+       spin_lock(&rq->lock);
+       if (unlikely(rt_task(p))) {
+               /*
+                * RR tasks need a special form of timeslice management.
+                * FIFO tasks have no timeslices.
+                */
+               if ((p->policy == SCHED_RR) && !--p->time_slice) {
+                       p->time_slice = NICE_TO_TIMESLICE(p->__nice);
+                       p->need_resched = 1;
+
+                       /* put it at the end of the queue: */
+                       dequeue_task(p, rq->active);
+                       enqueue_task(p, rq->active);
+               }
+               goto out;
+       }
        /*
-        * from this point on nothing can prevent us from
-        * switching to the next task, save this fact in
-        * sched_data.
-        */
-       sched_data->curr = next;
-       task_set_cpu(next, this_cpu);
-       spin_unlock_irq(&runqueue_lock);
-
-       if (unlikely(prev == next)) {
-               /* We won't go through the normal tail, so do this by hand */
-               prev->policy &= ~SCHED_YIELD;
-               goto same_process;
+        * The task was running during this tick - update the
+        * time slice counter and the sleep average. Note: we
+        * do not update a process's priority until it either
+        * goes to sleep or uses up its timeslice. This makes
+        * it possible for interactive tasks to use up their
+        * timeslices at their highest priority levels.
+        */
+       if (p->sleep_avg)
+               p->sleep_avg--;
+       if (!--p->time_slice) {
+               dequeue_task(p, rq->active);
+               p->need_resched = 1;
+               p->prio = effective_prio(p);
+               p->time_slice = NICE_TO_TIMESLICE(p->__nice);
+
+               if (!TASK_INTERACTIVE(p) || EXPIRED_STARVING(rq)) {
+                       if (!rq->expired_timestamp)
+                               rq->expired_timestamp = jiffies;
+                       enqueue_task(p, rq->expired);
+               } else
+                       enqueue_task(p, rq->active);
        }
+out:
+#if CONFIG_SMP
+       if (!(now % BUSY_REBALANCE_TICK))
+               load_balance(rq, 0);
+#endif
+       spin_unlock(&rq->lock);
+}
 
-#ifdef CONFIG_SMP
-       /*
-        * maintain the per-process 'last schedule' value.
-        * (this has to be recalculated even if we reschedule to
-        * the same process) Currently this is only used on SMP,
-        * and it's approximate, so we do not have to maintain
-        * it while holding the runqueue spinlock.
-        */
-       sched_data->last_schedule = get_cycles();
+void scheduling_functions_start_here(void) { }
 
-       /*
-        * We drop the scheduler lock early (it's a global spinlock),
-        * thus we have to lock the previous process from getting
-        * rescheduled during switch_to().
-        */
+/*
+ * 'schedule()' is the main scheduler function.
+ */
+asmlinkage void schedule(void)
+{
+       task_t *prev = current, *next;
+       runqueue_t *rq = this_rq();
+       prio_array_t *array;
+       list_t *queue;
+       int idx;
 
-#endif /* CONFIG_SMP */
+       if (unlikely(in_interrupt()))
+               BUG();
+       release_kernel_lock(prev, smp_processor_id());
+       spin_lock_irq(&rq->lock);
 
-       kstat.context_swtch++;
-       /*
-        * there are 3 processes which are affected by a context switch:
-        *
-        * prev == .... ==> (last => next)
-        *
-        * It's the 'much more previous' 'prev' that is on next's stack,
-        * but prev is set to (the just run) 'last' process by switch_to().
-        * This might sound slightly confusing but makes tons of sense.
-        */
-       prepare_to_switch();
-       {
-               struct mm_struct *mm = next->mm;
-               struct mm_struct *oldmm = prev->active_mm;
-               if (!mm) {
-                       if (next->active_mm) BUG();
-                       next->active_mm = oldmm;
-                       atomic_inc(&oldmm->mm_count);
-                       enter_lazy_tlb(oldmm, next, this_cpu);
-               } else {
-                       if (next->active_mm != mm) BUG();
-                       switch_mm(oldmm, mm, next, this_cpu);
+       switch (prev->state) {
+       case TASK_RUNNING:
+               prev->sleep_timestamp = jiffies;
+               break;
+       case TASK_INTERRUPTIBLE:
+               if (unlikely(signal_pending(prev))) {
+                       prev->state = TASK_RUNNING;
+                       prev->sleep_timestamp = jiffies;
+                       break;
                }
+       default:
+               deactivate_task(prev, rq);
+       }
+#if CONFIG_SMP
+pick_next_task:
+#endif
+       if (unlikely(!rq->nr_running)) {
+#if CONFIG_SMP
+               load_balance(rq, 1);
+               if (rq->nr_running)
+                       goto pick_next_task;
+#endif
+               next = rq->idle;
+               rq->expired_timestamp = 0;
+               goto switch_tasks;
+       }
 
-               if (!prev->mm) {
-                       prev->active_mm = NULL;
-                       mmdrop(oldmm);
-               }
+       array = rq->active;
+       if (unlikely(!array->nr_active)) {
+               /*
+                * Switch the active and expired arrays.
+                */
+               rq->active = rq->expired;
+               rq->expired = array;
+               array = rq->active;
+               rq->expired_timestamp = 0;
        }
 
-       /*
-        * This just switches the register state and the
-        * stack.
-        */
-       switch_to(prev, next, prev);
-       __schedule_tail(prev);
+       idx = sched_find_first_bit(array->bitmap);
+       queue = array->queue + idx;
+       next = list_entry(queue->next, task_t, run_list);
+
+switch_tasks:
+       prefetch(next);
+       prev->need_resched = 0;
+
+       if (likely(prev != next)) {
+               rq->nr_switches++;
+               rq->curr = next;
+               context_switch(prev, next);
+               /*
+                * The runqueue pointer might be from another CPU
+                * if the new task was last running on a different
+                * CPU - thus re-load it.
+                */
+               barrier();
+               rq = this_rq();
+       }
+       spin_unlock_irq(&rq->lock);
 
-same_process:
        reacquire_kernel_lock(current);
-       if (current->need_resched)
-               goto need_resched_back;
        return;
 }
 
 /*
- * The core wakeup function.  Non-exclusive wakeups (nr_exclusive == 0) just wake everything
- * up.  If it's an exclusive wakeup (nr_exclusive == small +ve number) then we wake all the
- * non-exclusive tasks and one exclusive task.
+ * The core wakeup function.  Non-exclusive wakeups (nr_exclusive == 0) just
+ * wake everything up.  If it's an exclusive wakeup (nr_exclusive == small +ve
+ * number) then we wake all the non-exclusive tasks and one exclusive task.
  *
  * There are circumstances in which we can try to wake a task which has already
- * started to run but is not in state TASK_RUNNING.  try_to_wake_up() returns zero
- * in this (rare) case, and we handle it by contonuing to scan the queue.
+ * started to run but is not in state TASK_RUNNING.  try_to_wake_up() returns
+ * zero in this (rare) case, and we handle it by continuing to scan the queue.
  */
 static inline void __wake_up_common (wait_queue_head_t *q, unsigned int mode,
                                     int nr_exclusive, const int sync)
 {
        struct list_head *tmp;
-       struct task_struct *p;
+       task_t *p;
 
-       CHECK_MAGIC_WQHEAD(q);
-       WQ_CHECK_LIST_HEAD(&q->task_list);
-       
        list_for_each(tmp,&q->task_list) {
                unsigned int state;
-                wait_queue_t *curr = list_entry(tmp, wait_queue_t, task_list);
+               wait_queue_t *curr = list_entry(tmp, wait_queue_t, task_list);
 
-               CHECK_MAGIC(curr->__magic);
                p = curr->task;
                state = p->state;
-               if (state & mode) {
-                       WQ_NOTE_WAKER(curr);
-                       if (try_to_wake_up(p, sync) && (curr->flags&WQ_FLAG_EXCLUSIVE) && !--nr_exclusive)
-                               break;
-               }
+               if ((state & mode) &&
+                               try_to_wake_up(p, sync) &&
+                               ((curr->flags & WQ_FLAG_EXCLUSIVE) &&
+                                       !--nr_exclusive))
+                       break;
        }
 }
 
@@ -850,8 +846,70 @@
        return timeout;
 }
 
+/*
+ * Change the current task's CPU affinity. Migrate the process to a
+ * proper CPU and schedule away if the current CPU is removed from
+ * the allowed bitmask.
+ */
+void set_cpus_allowed(task_t *p, unsigned long new_mask)
+{
+       new_mask &= cpu_online_map;
+       if (!new_mask)
+               BUG();
+
+       p->cpus_allowed = new_mask;
+       /*
+        * Can the task run on the current CPU? If not then
+        * migrate the process off to a proper CPU.
+        */
+       if (new_mask & (1UL << smp_processor_id()))
+               return;
+#if CONFIG_SMP
+       current->state = TASK_UNINTERRUPTIBLE;
+       smp_migrate_task(__ffs(new_mask), current);
+
+       schedule();
+#endif
+}
+
 void scheduling_functions_end_here(void) { }
 
+void set_user_nice(task_t *p, long nice)
+{
+       unsigned long flags;
+       prio_array_t *array;
+       runqueue_t *rq;
+
+       if (p->__nice == nice)
+               return;
+       /*
+        * We have to be careful, if called from sys_setpriority(),
+        * the task might be in the middle of scheduling on another CPU.
+        */
+       rq = lock_task_rq(p, &flags);
+       if (rt_task(p)) {
+               p->__nice = nice;
+               goto out_unlock;
+       }
+       array = p->array;
+       if (array)
+               dequeue_task(p, array);
+       p->__nice = nice;
+       p->prio = NICE_TO_PRIO(nice);
+       if (array) {
+               enqueue_task(p, array);
+               /*
+                * If the task is running and lowered its priority,
+                * or increased its priority then reschedule its CPU:
+                */
+               if ((nice < p->__nice) ||
+                               ((p->__nice < nice) && (p == rq->curr)))
+                       resched_task(rq->curr);
+       }
+out_unlock:
+       unlock_task_rq(rq, &flags);
+}
+
 #ifndef __alpha__
 
 /*
@@ -862,7 +920,7 @@
 
 asmlinkage long sys_nice(int increment)
 {
-       long newprio;
+       long nice;
 
        /*
         *      Setpriority might change our priority at the same moment.
@@ -878,32 +936,30 @@
        if (increment > 40)
                increment = 40;
 
-       newprio = current->nice + increment;
-       if (newprio < -20)
-               newprio = -20;
-       if (newprio > 19)
-               newprio = 19;
-       current->nice = newprio;
+       nice = current->__nice + increment;
+       if (nice < -20)
+               nice = -20;
+       if (nice > 19)
+               nice = 19;
+       set_user_nice(current, nice);
        return 0;
 }
 
 #endif
 
-static inline struct task_struct *find_process_by_pid(pid_t pid)
+static inline task_t *find_process_by_pid(pid_t pid)
 {
-       struct task_struct *tsk = current;
-
-       if (pid)
-               tsk = find_task_by_pid(pid);
-       return tsk;
+       return pid ? find_task_by_pid(pid) : current;
 }
 
-static int setscheduler(pid_t pid, int policy, 
-                       struct sched_param *param)
+static int setscheduler(pid_t pid, int policy, struct sched_param *param)
 {
        struct sched_param lp;
-       struct task_struct *p;
+       prio_array_t *array;
+       unsigned long flags;
+       runqueue_t *rq;
        int retval;
+       task_t *p;
 
        retval = -EINVAL;
        if (!param || pid < 0)
@@ -917,14 +973,19 @@
         * We play safe to avoid deadlocks.
         */
        read_lock_irq(&tasklist_lock);
-       spin_lock(&runqueue_lock);
 
        p = find_process_by_pid(pid);
 
        retval = -ESRCH;
        if (!p)
-               goto out_unlock;
-                       
+               goto out_unlock_tasklist;
+
+       /*
+        * To be able to change p->policy safely, the apropriate
+        * runqueue lock must be held.
+        */
+       rq = lock_task_rq(p, &flags);
+
        if (policy < 0)
                policy = p->policy;
        else {
@@ -945,30 +1006,36 @@
                goto out_unlock;
 
        retval = -EPERM;
-       if ((policy == SCHED_FIFO || policy == SCHED_RR) && 
+       if ((policy == SCHED_FIFO || policy == SCHED_RR) &&
            !capable(CAP_SYS_NICE))
                goto out_unlock;
        if ((current->euid != p->euid) && (current->euid != p->uid) &&
            !capable(CAP_SYS_NICE))
                goto out_unlock;
 
+       array = p->array;
+       if (array)
+               deactivate_task(p, task_rq(p));
        retval = 0;
        p->policy = policy;
        p->rt_priority = lp.sched_priority;
-       if (task_on_runqueue(p))
-               move_first_runqueue(p);
-
-       current->need_resched = 1;
+       if (rt_task(p))
+               p->prio = 99-p->rt_priority;
+       else
+               p->prio = NICE_TO_PRIO(p->__nice);
+       if (array)
+               activate_task(p, task_rq(p));
 
 out_unlock:
-       spin_unlock(&runqueue_lock);
+       unlock_task_rq(rq, &flags);
+out_unlock_tasklist:
        read_unlock_irq(&tasklist_lock);
 
 out_nounlock:
        return retval;
 }
 
-asmlinkage long sys_sched_setscheduler(pid_t pid, int policy, 
+asmlinkage long sys_sched_setscheduler(pid_t pid, int policy,
                                      struct sched_param *param)
 {
        return setscheduler(pid, policy, param);
@@ -981,7 +1048,7 @@
 
 asmlinkage long sys_sched_getscheduler(pid_t pid)
 {
-       struct task_struct *p;
+       task_t *p;
        int retval;
 
        retval = -EINVAL;
@@ -992,7 +1059,7 @@
        read_lock(&tasklist_lock);
        p = find_process_by_pid(pid);
        if (p)
-               retval = p->policy & ~SCHED_YIELD;
+               retval = p->policy;
        read_unlock(&tasklist_lock);
 
 out_nounlock:
@@ -1001,7 +1068,7 @@
 
 asmlinkage long sys_sched_getparam(pid_t pid, struct sched_param *param)
 {
-       struct task_struct *p;
+       task_t *p;
        struct sched_param lp;
        int retval;
 
@@ -1032,42 +1099,38 @@
 
 asmlinkage long sys_sched_yield(void)
 {
+       runqueue_t *rq = this_rq();
+       prio_array_t *array;
+
        /*
-        * Trick. sched_yield() first counts the number of truly 
-        * 'pending' runnable processes, then returns if it's
-        * only the current processes. (This test does not have
-        * to be atomic.) In threaded applications this optimization
-        * gets triggered quite often.
+        * Decrease the yielding task's priority by one, to avoid
+        * livelocks. This priority loss is temporary, it's recovered
+        * once the current timeslice expires.
+        *
+        * If priority is already MAX_PRIO-1 then we still
+        * roundrobin the task within the runlist.
         */
-
-       int nr_pending = nr_running;
-
-#if CONFIG_SMP
-       int i;
-
-       // Subtract non-idle processes running on other CPUs.
-       for (i = 0; i < smp_num_cpus; i++) {
-               int cpu = cpu_logical_map(i);
-               if (aligned_data[cpu].schedule_data.curr != idle_task(cpu))
-                       nr_pending--;
+       spin_lock_irq(&rq->lock);
+       array = current->array;
+       /*
+        * If the task has reached maximum priority (or is a RT task)
+        * then just requeue the task to the end of the runqueue:
+        */
+       if (likely(current->prio == MAX_PRIO-1 || rt_task(current))) {
+               list_del(&current->run_list);
+               list_add_tail(&current->run_list, array->queue + current->prio);
+       } else {
+               list_del(&current->run_list);
+               if (list_empty(array->queue + current->prio))
+                       __clear_bit(current->prio, array->bitmap);
+               current->prio++;
+               list_add_tail(&current->run_list, array->queue + current->prio);
+               __set_bit(current->prio, array->bitmap);
        }
-#else
-       // on UP this process is on the runqueue as well
-       nr_pending--;
-#endif
-       if (nr_pending) {
-               /*
-                * This process can only be rescheduled by us,
-                * so this is safe without any locking.
-                */
-               if (current->policy == SCHED_OTHER)
-                       current->policy |= SCHED_YIELD;
-               current->need_resched = 1;
+       spin_unlock(&rq->lock);
+
+       schedule();
 
-               spin_lock_irq(&runqueue_lock);
-               move_last_runqueue(current);
-               spin_unlock_irq(&runqueue_lock);
-       }
        return 0;
 }
 
@@ -1105,7 +1168,7 @@
 asmlinkage long sys_sched_rr_get_interval(pid_t pid, struct timespec *interval)
 {
        struct timespec t;
-       struct task_struct *p;
+       task_t *p;
        int retval = -EINVAL;
 
        if (pid < 0)
@@ -1115,8 +1178,8 @@
        read_lock(&tasklist_lock);
        p = find_process_by_pid(pid);
        if (p)
-               jiffies_to_timespec(p->policy & SCHED_FIFO ? 0 : NICE_TO_TICKS(p->nice),
-                                   &t);
+               jiffies_to_timespec(p->policy & SCHED_FIFO ?
+                                        0 : NICE_TO_TIMESLICE(p->__nice), &t);
        read_unlock(&tasklist_lock);
        if (p)
                retval = copy_to_user(interval, &t, sizeof(t)) ? -EFAULT : 0;
@@ -1124,14 +1187,14 @@
        return retval;
 }
 
-static void show_task(struct task_struct * p)
+static void show_task(task_t * p)
 {
        unsigned long free = 0;
        int state;
        static const char * stat_nam[] = { "R", "S", "D", "Z", "T", "W" };
 
        printk("%-13.13s ", p->comm);
-       state = p->state ? ffz(~p->state) + 1 : 0;
+       state = p->state ? __ffs(p->state) + 1 : 0;
        if (((unsigned) state) < sizeof(stat_nam)/sizeof(char *))
                printk(stat_nam[state]);
        else
@@ -1172,7 +1235,7 @@
                printk(" (NOTLB)\n");
 
        {
-               extern void show_trace_task(struct task_struct *tsk);
+               extern void show_trace_task(task_t *tsk);
                show_trace_task(p);
        }
 }
@@ -1194,7 +1257,7 @@
 
 void show_state(void)
 {
-       struct task_struct *p;
+       task_t *p;
 
 #if (BITS_PER_LONG == 32)
        printk("\n"
@@ -1217,121 +1280,88 @@
        read_unlock(&tasklist_lock);
 }
 
-/**
- * reparent_to_init() - Reparent the calling kernel thread to the init task.
- *
- * If a kernel thread is launched as a result of a system call, or if
- * it ever exits, it should generally reparent itself to init so that
- * it is correctly cleaned up on exit.
- *
- * The various task state such as scheduling policy and priority may have
- * been inherited fro a user process, so we reset them to sane values here.
- *
- * NOTE that reparent_to_init() gives the caller full capabilities.
- */
-void reparent_to_init(void)
+static inline void double_rq_lock(runqueue_t *rq1, runqueue_t *rq2)
 {
-       struct task_struct *this_task = current;
-
-       write_lock_irq(&tasklist_lock);
-
-       /* Reparent to init */
-       REMOVE_LINKS(this_task);
-       this_task->p_pptr = child_reaper;
-       this_task->p_opptr = child_reaper;
-       SET_LINKS(this_task);
-
-       /* Set the exit signal to SIGCHLD so we signal init on exit */
-       this_task->exit_signal = SIGCHLD;
-
-       /* We also take the runqueue_lock while altering task fields
-        * which affect scheduling decisions */
-       spin_lock(&runqueue_lock);
-
-       this_task->ptrace = 0;
-       this_task->nice = DEF_NICE;
-       this_task->policy = SCHED_OTHER;
-       /* cpus_allowed? */
-       /* rt_priority? */
-       /* signals? */
-       this_task->cap_effective = CAP_INIT_EFF_SET;
-       this_task->cap_inheritable = CAP_INIT_INH_SET;
-       this_task->cap_permitted = CAP_FULL_SET;
-       this_task->keep_capabilities = 0;
-       memcpy(this_task->rlim, init_task.rlim, sizeof(*(this_task->rlim)));
-       this_task->user = INIT_USER;
-
-       spin_unlock(&runqueue_lock);
-       write_unlock_irq(&tasklist_lock);
+       if (rq1 == rq2)
+               spin_lock(&rq1->lock);
+       else {
+               if (rq1 < rq2) {
+                       spin_lock(&rq1->lock);
+                       spin_lock(&rq2->lock);
+               } else {
+                       spin_lock(&rq2->lock);
+                       spin_lock(&rq1->lock);
+               }
+       }
 }
 
-/*
- *     Put all the gunge required to become a kernel thread without
- *     attached user resources in one place where it belongs.
- */
-
-void daemonize(void)
+static inline void double_rq_unlock(runqueue_t *rq1, runqueue_t *rq2)
 {
-       struct fs_struct *fs;
-
-
-       /*
-        * If we were started as result of loading a module, close all of the
-        * user space pages.  We don't need them, and if we didn't close them
-        * they would be locked into memory.
-        */
-       exit_mm(current);
-
-       current->session = 1;
-       current->pgrp = 1;
-       current->tty = NULL;
-
-       /* Become as one with the init task */
-
-       exit_fs(current);       /* current->fs->count--; */
-       fs = init_task.fs;
-       current->fs = fs;
-       atomic_inc(&fs->count);
-       exit_files(current);
-       current->files = init_task.files;
-       atomic_inc(&current->files->count);
+       spin_unlock(&rq1->lock);
+       if (rq1 != rq2)
+               spin_unlock(&rq2->lock);
 }
 
-extern unsigned long wait_init_idle;
-
-void __init init_idle(void)
+void __init init_idle(task_t *idle, int cpu)
 {
-       struct schedule_data * sched_data;
-       sched_data = &aligned_data[smp_processor_id()].schedule_data;
+       runqueue_t *idle_rq = cpu_rq(cpu), *rq = idle->array->rq;
+       unsigned long flags;
 
-       if (current != &init_task && task_on_runqueue(current)) {
-               printk("UGH! (%d:%d) was on the runqueue, removing.\n",
-                       smp_processor_id(), current->pid);
-               del_from_runqueue(current);
-       }
-       sched_data->curr = current;
-       sched_data->last_schedule = get_cycles();
-       clear_bit(current->processor, &wait_init_idle);
+       __save_flags(flags);
+       __cli();
+       double_rq_lock(idle_rq, rq);
+
+       idle_rq->curr = idle_rq->idle = idle;
+       deactivate_task(idle, rq);
+       idle->array = NULL;
+       idle->prio = MAX_PRIO;
+       idle->state = TASK_RUNNING;
+       idle->cpu = cpu;
+       double_rq_unlock(idle_rq, rq);
+       idle->need_resched = 1;
+       __restore_flags(flags);
 }
 
-extern void init_timervecs (void);
+extern void init_timervecs(void);
+extern void timer_bh(void);
+extern void tqueue_bh(void);
+extern void immediate_bh(void);
 
 void __init sched_init(void)
 {
+       runqueue_t *rq;
+       int i, j, k;
+
+       for (i = 0; i < NR_CPUS; i++) {
+               runqueue_t *rq = cpu_rq(i);
+               prio_array_t *array;
+
+               rq->active = rq->arrays + 0;
+               rq->expired = rq->arrays + 1;
+               spin_lock_init(&rq->lock);
+
+               for (j = 0; j < 2; j++) {
+                       array = rq->arrays + j;
+                       array->rq = rq;
+                       array->lock = &rq->lock;
+                       for (k = 0; k < MAX_PRIO; k++) {
+                               INIT_LIST_HEAD(array->queue + k);
+                               __clear_bit(k, array->bitmap);
+                       }
+                       // delimiter for bitsearch
+                       __set_bit(MAX_PRIO, array->bitmap);
+               }
+       }
        /*
         * We have to do a little magic to get the first
         * process right in SMP mode.
         */
-       int cpu = smp_processor_id();
-       int nr;
-
-       init_task.processor = cpu;
-
-       for(nr = 0; nr < PIDHASH_SZ; nr++)
-               pidhash[nr] = NULL;
+       rq = this_rq();
+       rq->curr = current;
+       rq->idle = current;
+       wake_up_process(current);
 
        init_timervecs();
-
        init_bh(TIMER_BH, timer_bh);
        init_bh(TQUEUE_BH, tqueue_bh);
        init_bh(IMMEDIATE_BH, immediate_bh);
@@ -1340,5 +1370,5 @@
         * The boot idle thread does lazy MMU switching as well:
         */
        atomic_inc(&init_mm.mm_count);
-       enter_lazy_tlb(&init_mm, current, cpu);
+       enter_lazy_tlb(&init_mm, current, smp_processor_id());
 }
--- linux/kernel/exit.c.orig    Sun Jan  6 13:55:56 2002
+++ linux/kernel/exit.c Mon Jan 28 18:01:36 2002
@@ -27,49 +27,42 @@
 
 static void release_task(struct task_struct * p)
 {
-       if (p != current) {
+       unsigned long flags;
+
+       if (p == current)
+               BUG();
 #ifdef CONFIG_SMP
-               /*
-                * Wait to make sure the process isn't on the
-                * runqueue (active on some other CPU still)
-                */
-               for (;;) {
-                       task_lock(p);
-                       if (!task_has_cpu(p))
-                               break;
-                       task_unlock(p);
-                       do {
-                               cpu_relax();
-                               barrier();
-                       } while (task_has_cpu(p));
-               }
-               task_unlock(p);
+       wait_task_inactive(p);
 #endif
-               atomic_dec(&p->user->processes);
-               free_uid(p->user);
-               unhash_process(p);
-
-               release_thread(p);
-               current->cmin_flt += p->min_flt + p->cmin_flt;
-               current->cmaj_flt += p->maj_flt + p->cmaj_flt;
-               current->cnswap += p->nswap + p->cnswap;
-               /*
-                * Potentially available timeslices are retrieved
-                * here - this way the parent does not get penalized
-                * for creating too many processes.
-                *
-                * (this cannot be used to artificially 'generate'
-                * timeslices, because any timeslice recovered here
-                * was given away by the parent in the first place.)
-                */
-               current->counter += p->counter;
-               if (current->counter >= MAX_COUNTER)
-                       current->counter = MAX_COUNTER;
-               p->pid = 0;
-               free_task_struct(p);
-       } else {
-               printk("task releasing itself\n");
-       }
+       atomic_dec(&p->user->processes);
+       free_uid(p->user);
+       unhash_process(p);
+
+       release_thread(p);
+       current->cmin_flt += p->min_flt + p->cmin_flt;
+       current->cmaj_flt += p->maj_flt + p->cmaj_flt;
+       current->cnswap += p->nswap + p->cnswap;
+       /*
+        * Potentially available timeslices are retrieved
+        * here - this way the parent does not get penalized
+        * for creating too many processes.
+        *
+        * (this cannot be used to artificially 'generate'
+        * timeslices, because any timeslice recovered here
+        * was given away by the parent in the first place.)
+        */
+       __save_flags(flags);
+       __cli();
+       current->time_slice += p->time_slice;
+       if (current->time_slice > MAX_TIMESLICE)
+               current->time_slice = MAX_TIMESLICE;
+       if (p->sleep_avg < current->sleep_avg)
+               current->sleep_avg = (current->sleep_avg * EXIT_WEIGHT +
+                       p->sleep_avg) / (EXIT_WEIGHT + 1);
+       __restore_flags(flags);
+
+       p->pid = 0;
+       free_task_struct(p);
 }
 
 /*
@@ -147,6 +140,79 @@
        }
        read_unlock(&tasklist_lock);
        return retval;
+}
+
+/**
+ * reparent_to_init() - Reparent the calling kernel thread to the init task.
+ *
+ * If a kernel thread is launched as a result of a system call, or if
+ * it ever exits, it should generally reparent itself to init so that
+ * it is correctly cleaned up on exit.
+ *
+ * The various task state such as scheduling policy and priority may have
+ * been inherited from a user process, so we reset them to sane values here.
+ *
+ * NOTE that reparent_to_init() gives the caller full capabilities.
+ */
+void reparent_to_init(void)
+{
+       write_lock_irq(&tasklist_lock);
+
+       /* Reparent to init */
+       REMOVE_LINKS(current);
+       current->p_pptr = child_reaper;
+       current->p_opptr = child_reaper;
+       SET_LINKS(current);
+
+       /* Set the exit signal to SIGCHLD so we signal init on exit */
+       current->exit_signal = SIGCHLD;
+
+       current->ptrace = 0;
+       if ((current->policy == SCHED_OTHER) && (current->__nice < DEF_USER_NICE))
+               set_user_nice(current, DEF_USER_NICE);
+       /* cpus_allowed? */
+       /* rt_priority? */
+       /* signals? */
+       current->cap_effective = CAP_INIT_EFF_SET;
+       current->cap_inheritable = CAP_INIT_INH_SET;
+       current->cap_permitted = CAP_FULL_SET;
+       current->keep_capabilities = 0;
+       memcpy(current->rlim, init_task.rlim, sizeof(*(current->rlim)));
+       current->user = INIT_USER;
+
+       write_unlock_irq(&tasklist_lock);
+}
+
+/*
+ *     Put all the gunge required to become a kernel thread without
+ *     attached user resources in one place where it belongs.
+ */
+
+void daemonize(void)
+{
+       struct fs_struct *fs;
+
+
+       /*
+        * If we were started as result of loading a module, close all of the
+        * user space pages.  We don't need them, and if we didn't close them
+        * they would be locked into memory.
+        */
+       exit_mm(current);
+
+       current->session = 1;
+       current->pgrp = 1;
+       current->tty = NULL;
+
+       /* Become as one with the init task */
+
+       exit_fs(current);       /* current->fs->count--; */
+       fs = init_task.fs;
+       current->fs = fs;
+       atomic_inc(&fs->count);
+       exit_files(current);
+       current->files = init_task.files;
+       atomic_inc(&current->files->count);
 }
 
 /*
--- linux/kernel/capability.c.orig      Sat Jun 24 06:06:37 2000
+++ linux/kernel/capability.c   Sun Jan  6 13:56:25 2002
@@ -8,6 +8,8 @@
 #include <linux/mm.h>
 #include <asm/uaccess.h>
 
+unsigned securebits = SECUREBITS_DEFAULT; /* systemwide security settings */
+
 kernel_cap_t cap_bset = CAP_INIT_EFF_SET;
 
 /* Note: never hold tasklist_lock while spinning for this one */
--- linux/kernel/timer.c.orig   Sun Jan  6 13:55:49 2002
+++ linux/kernel/timer.c        Mon Jan 21 12:53:05 2002
@@ -25,6 +25,8 @@
 
 #include <asm/uaccess.h>
 
+struct kernel_stat kstat;
+
 /*
  * Timekeeping variables
  */
@@ -583,17 +585,16 @@
 
        update_one_process(p, user_tick, system, cpu);
        if (p->pid) {
-               if (--p->counter <= 0) {
-                       p->counter = 0;
-                       p->need_resched = 1;
-               }
-               if (p->nice > 0)
+               if (p->__nice > 0)
                        kstat.per_cpu_nice[cpu] += user_tick;
                else
                        kstat.per_cpu_user[cpu] += user_tick;
                kstat.per_cpu_system[cpu] += system;
-       } else if (local_bh_count(cpu) || local_irq_count(cpu) > 1)
-               kstat.per_cpu_system[cpu] += system;
+       } else {
+               if (local_bh_count(cpu) || local_irq_count(cpu) > 1)
+                       kstat.per_cpu_system[cpu] += system;
+       }
+       scheduler_tick(p);
 }
 
 /*
@@ -794,6 +795,89 @@
 
 #endif
 
+static void process_timeout(unsigned long __data)
+{
+       wake_up_process((task_t *)__data);
+}
+
+/**
+ * schedule_timeout - sleep until timeout
+ * @timeout: timeout value in jiffies
+ *
+ * Make the current task sleep until @timeout jiffies have
+ * elapsed. The routine will return immediately unless
+ * the current task state has been set (see set_current_state()).
+ *
+ * You can set the task state as follows -
+ *
+ * %TASK_UNINTERRUPTIBLE - at least @timeout jiffies are guaranteed to
+ * pass before the routine returns. The routine will return 0
+ *
+ * %TASK_INTERRUPTIBLE - the routine may return early if a signal is
+ * delivered to the current task. In this case the remaining time
+ * in jiffies will be returned, or 0 if the timer expired in time
+ *
+ * The current task state is guaranteed to be TASK_RUNNING when this 
+ * routine returns.
+ *
+ * Specifying a @timeout value of %MAX_SCHEDULE_TIMEOUT will schedule
+ * the CPU away without a bound on the timeout. In this case the return
+ * value will be %MAX_SCHEDULE_TIMEOUT.
+ *
+ * In all cases the return value is guaranteed to be non-negative.
+ */
+signed long schedule_timeout(signed long timeout)
+{
+       struct timer_list timer;
+       unsigned long expire;
+
+       switch (timeout)
+       {
+       case MAX_SCHEDULE_TIMEOUT:
+               /*
+                * These two special cases are useful to be comfortable
+                * in the caller. Nothing more. We could take
+                * MAX_SCHEDULE_TIMEOUT from one of the negative value
+                * but I' d like to return a valid offset (>=0) to allow
+                * the caller to do everything it want with the retval.
+                */
+               schedule();
+               goto out;
+       default:
+               /*
+                * Another bit of PARANOID. Note that the retval will be
+                * 0 since no piece of kernel is supposed to do a check
+                * for a negative retval of schedule_timeout() (since it
+                * should never happens anyway). You just have the printk()
+                * that will tell you if something is gone wrong and where.
+                */
+               if (timeout < 0)
+               {
+                       printk(KERN_ERR "schedule_timeout: wrong timeout "
+                              "value %lx from %p\n", timeout,
+                              __builtin_return_address(0));
+                       current->state = TASK_RUNNING;
+                       goto out;
+               }
+       }
+
+       expire = timeout + jiffies;
+
+       init_timer(&timer);
+       timer.expires = expire;
+       timer.data = (unsigned long) current;
+       timer.function = process_timeout;
+
+       add_timer(&timer);
+       schedule();
+       del_timer_sync(&timer);
+
+       timeout = expire - jiffies;
+
+ out:
+       return timeout < 0 ? 0 : timeout;
+}
+
 /* Thread ID - the internal kernel "pid" */
 asmlinkage long sys_gettid(void)
 {
@@ -840,4 +924,3 @@
        }
        return 0;
 }
-
--- linux/kernel/fork.c.orig    Sun Jan  6 13:55:56 2002
+++ linux/kernel/fork.c Thu Jan 24 13:45:09 2002
@@ -28,7 +28,6 @@
 
 /* The idle threads do not count.. */
 int nr_threads;
-int nr_running;
 
 int max_threads;
 unsigned long total_forks;     /* Handle normal Linux uptimes. */
@@ -36,6 +35,8 @@
 
 struct task_struct *pidhash[PIDHASH_SZ];
 
+rwlock_t tasklist_lock __cacheline_aligned = RW_LOCK_UNLOCKED;  /* outer */
+
 void add_wait_queue(wait_queue_head_t *q, wait_queue_t * wait)
 {
        unsigned long flags;
@@ -563,6 +564,7 @@
            struct pt_regs *regs, unsigned long stack_size)
 {
        int retval;
+       unsigned long flags;
        struct task_struct *p;
        struct completion vfork;
 
@@ -611,8 +613,7 @@
        copy_flags(clone_flags, p);
        p->pid = get_pid(clone_flags);
 
-       p->run_list.next = NULL;
-       p->run_list.prev = NULL;
+       INIT_LIST_HEAD(&p->run_list);
 
        p->p_cptr = NULL;
        init_waitqueue_head(&p->wait_chldexit);
@@ -638,14 +639,15 @@
 #ifdef CONFIG_SMP
        {
                int i;
-               p->cpus_runnable = ~0UL;
-               p->processor = current->processor;
+
                /* ?? should we just memset this ?? */
                for(i = 0; i < smp_num_cpus; i++)
-                       p->per_cpu_utime[i] = p->per_cpu_stime[i] = 0;
+                       p->per_cpu_utime[cpu_logical_map(i)] =
+                               p->per_cpu_stime[cpu_logical_map(i)] = 0;
                spin_lock_init(&p->sigmask_lock);
        }
 #endif
+       p->array = NULL;
        p->lock_depth = -1;             /* -1 = no lock */
        p->start_time = jiffies;
 
@@ -677,15 +679,27 @@
        p->pdeath_signal = 0;
 
        /*
-        * "share" dynamic priority between parent and child, thus the
-        * total amount of dynamic priorities in the system doesnt change,
-        * more scheduling fairness. This is only important in the first
-        * timeslice, on the long run the scheduling behaviour is unchanged.
+        * Share the timeslice between parent and child, thus the
+        * total amount of pending timeslices in the system doesnt change,
+        * resulting in more scheduling fairness.
         */
-       p->counter = (current->counter + 1) >> 1;
-       current->counter >>= 1;
-       if (!current->counter)
-               current->need_resched = 1;
+       __save_flags(flags);
+       __cli();
+       if (!current->time_slice)
+               BUG();
+       p->time_slice = (current->time_slice + 1) >> 1;
+       current->time_slice >>= 1;
+       if (!current->time_slice) {
+               /*
+                * This case is rare, it happens when the parent has only
+                * a single jiffy left from its timeslice. Taking the
+                * runqueue lock is not a problem.
+                */
+               current->time_slice = 1;
+               scheduler_tick(current);
+       }
+       p->sleep_timestamp = jiffies;
+       __restore_flags(flags);
 
        /*
         * Ok, add it to the run-queues and make it
@@ -722,10 +736,23 @@
        if (p->ptrace & PT_PTRACED)
                send_sig(SIGSTOP, p, 1);
 
+#define RUN_CHILD_FIRST 1
+#if RUN_CHILD_FIRST
+       wake_up_forked_process(p);      /* do this last */
+#else
        wake_up_process(p);             /* do this last */
+#endif
        ++total_forks;
        if (clone_flags & CLONE_VFORK)
                wait_for_completion(&vfork);
+#if RUN_CHILD_FIRST
+       else
+               /*
+                * Let the child process run first, to avoid most of the
+                * COW overhead when the child exec()s afterwards.
+                */
+               current->need_resched = 1;
+#endif
 
 fork_out:
        return retval;
--- linux/kernel/softirq.c.orig Sun Jan  6 13:55:53 2002
+++ linux/kernel/softirq.c      Wed Jan 16 00:52:11 2002
@@ -259,10 +259,9 @@
 
        while (test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) {
                current->state = TASK_RUNNING;
-               do {
-                       current->policy |= SCHED_YIELD;
-                       schedule();
-               } while (test_bit(TASKLET_STATE_SCHED, &t->state));
+               do
+                       sys_sched_yield();
+               while (test_bit(TASKLET_STATE_SCHED, &t->state));
        }
        tasklet_unlock_wait(t);
        clear_bit(TASKLET_STATE_SCHED, &t->state);
@@ -365,13 +364,13 @@
        int cpu = cpu_logical_map(bind_cpu);
 
        daemonize();
-       current->nice = 19;
+       set_user_nice(current, 19);
        sigfillset(&current->blocked);
 
        /* Migrate to the right CPU */
-       current->cpus_allowed = 1UL << cpu;
-       while (smp_processor_id() != cpu)
-               schedule();
+       set_cpus_allowed(current, 1UL << cpu);
+       if (cpu() != cpu)
+               BUG();
 
        sprintf(current->comm, "ksoftirqd_CPU%d", bind_cpu);
 
@@ -396,7 +395,7 @@
        }
 }
 
-static __init int spawn_ksoftirqd(void)
+__init int spawn_ksoftirqd(void)
 {
        int cpu;
 
@@ -405,14 +404,12 @@
                                  CLONE_FS | CLONE_FILES | CLONE_SIGNAL) < 0)
                        printk("spawn_ksoftirqd() failed for cpu %d\n", cpu);
                else {
-                       while (!ksoftirqd_task(cpu_logical_map(cpu))) {
-                               current->policy |= SCHED_YIELD;
-                               schedule();
-                       }
+                       while (!ksoftirqd_task(cpu_logical_map(cpu)))
+                               sys_sched_yield();
                }
        }
 
        return 0;
 }
 
-__initcall(spawn_ksoftirqd);
+__initcall(spawn_ksoftirqd);
--- linux/kernel/ptrace.c.orig  Sun Jan  6 13:55:57 2002
+++ linux/kernel/ptrace.c       Sun Jan  6 13:56:25 2002
@@ -31,20 +31,7 @@
                if (child->state != TASK_STOPPED)
                        return -ESRCH;
 #ifdef CONFIG_SMP
-               /* Make sure the child gets off its CPU.. */
-               for (;;) {
-                       task_lock(child);
-                       if (!task_has_cpu(child))
-                               break;
-                       task_unlock(child);
-                       do {
-                               if (child->state != TASK_STOPPED)
-                                       return -ESRCH;
-                               barrier();
-                               cpu_relax();
-                       } while (task_has_cpu(child));
-               }
-               task_unlock(child);
+               wait_task_inactive(child);
 #endif         
        }
 
--- linux/kernel/sys.c.orig     Sun Jan  6 13:55:47 2002
+++ linux/kernel/sys.c  Sun Jan  6 13:56:25 2002
@@ -220,10 +220,10 @@
                }
                if (error == -ESRCH)
                        error = 0;
-               if (niceval < p->nice && !capable(CAP_SYS_NICE))
+               if (niceval < p->__nice && !capable(CAP_SYS_NICE))
                        error = -EACCES;
                else
-                       p->nice = niceval;
+                       set_user_nice(p, niceval);
        }
        read_unlock(&tasklist_lock);
 
@@ -249,7 +249,7 @@
                long niceval;
                if (!proc_sel(p, which, who))
                        continue;
-               niceval = 20 - p->nice;
+               niceval = 20 - p->__nice;
                if (niceval > retval)
                        retval = niceval;
        }
--- linux/kernel/signal.c.orig  Sun Jan  6 13:55:56 2002
+++ linux/kernel/signal.c       Sun Jan  6 13:56:25 2002
@@ -478,12 +478,9 @@
         * process of changing - but no harm is done by that
         * other than doing an extra (lightweight) IPI interrupt.
         */
-       spin_lock(&runqueue_lock);
-       if (task_has_cpu(t) && t->processor != smp_processor_id())
-               smp_send_reschedule(t->processor);
-       spin_unlock(&runqueue_lock);
-#endif /* CONFIG_SMP */
-
+       if ((t->state == TASK_RUNNING) && (t->cpu != cpu()))
+               kick_if_running(t);
+#endif
        if (t->state & TASK_INTERRUPTIBLE) {
                wake_up_process(t);
                return;
--- linux/kernel/printk.c.orig  Sun Jan  6 13:55:57 2002
+++ linux/kernel/printk.c       Sun Jan  6 13:56:25 2002
@@ -25,6 +25,7 @@
 #include <linux/module.h>
 #include <linux/interrupt.h>                   /* For in_interrupt() */
 #include <linux/config.h>
+#include <linux/delay.h>
 
 #include <asm/uaccess.h>
 
--- linux/kernel/ksyms.c.orig   Sun Jan  6 13:55:57 2002
+++ linux/kernel/ksyms.c        Thu Jan 10 22:55:43 2002
@@ -437,6 +437,9 @@
 EXPORT_SYMBOL(interruptible_sleep_on_timeout);
 EXPORT_SYMBOL(schedule);
 EXPORT_SYMBOL(schedule_timeout);
+EXPORT_SYMBOL(sys_sched_yield);
+EXPORT_SYMBOL(set_user_nice);
+EXPORT_SYMBOL(set_cpus_allowed);
 EXPORT_SYMBOL(jiffies);
 EXPORT_SYMBOL(xtime);
 EXPORT_SYMBOL(do_gettimeofday);
@@ -448,6 +451,7 @@
 
 EXPORT_SYMBOL(kstat);
 EXPORT_SYMBOL(nr_running);
+EXPORT_SYMBOL(nr_context_switches);
 
 /* misc */
 EXPORT_SYMBOL(panic);
--- linux/mm/oom_kill.c.orig    Sun Jan  6 13:55:53 2002
+++ linux/mm/oom_kill.c Sun Jan  6 13:56:25 2002
@@ -82,7 +82,7 @@
         * Niced processes are most likely less important, so double
         * their badness points.
         */
-       if (p->nice > 0)
+       if (p->__nice > 0)
                points *= 2;
 
        /*
@@ -149,7 +149,7 @@
         * all the memory it needs. That way it should be able to
         * exit() and clear out its resources quickly...
         */
-       p->counter = 5 * HZ;
+       p->time_slice = 2 * MAX_TIMESLICE;
        p->flags |= PF_MEMALLOC | PF_MEMDIE;
 
        /* This process has hardware access, be more careful. */
@@ -188,8 +188,7 @@
         * killing itself before someone else gets the chance to ask
         * for more memory.
         */
-       current->policy |= SCHED_YIELD;
-       schedule();
+       yield();
        return;
 }
 
--- linux/mm/page_alloc.c.orig  Sun Jan  6 13:55:56 2002
+++ linux/mm/page_alloc.c       Fri Jan 25 14:26:36 2002
@@ -394,9 +394,8 @@
                return NULL;
 
        /* Yield for kswapd, and try again */
-       current->policy |= SCHED_YIELD;
        __set_current_state(TASK_RUNNING);
-       schedule();
+       yield();
        goto rebalance;
 }
 
--- linux/mm/highmem.c.orig     Sun Jan  6 13:55:57 2002
+++ linux/mm/highmem.c  Fri Jan 25 14:26:56 2002
@@ -354,9 +354,8 @@
        /* we need to wait I/O completion */
        run_task_queue(&tq_disk);
 
-       current->policy |= SCHED_YIELD;
        __set_current_state(TASK_RUNNING);
-       schedule();
+       yield();
        goto repeat_alloc;
 }
 
@@ -392,9 +391,8 @@
        /* we need to wait I/O completion */
        run_task_queue(&tq_disk);
 
-       current->policy |= SCHED_YIELD;
        __set_current_state(TASK_RUNNING);
-       schedule();
+       yield();
        goto repeat_alloc;
 }
 
--- linux/include/linux/sched.h.orig    Sun Jan  6 13:55:57 2002
+++ linux/include/linux/sched.h Mon Jan 28 18:48:01 2002
@@ -6,6 +6,7 @@
 extern unsigned long event;
 
 #include <linux/config.h>
+#include <linux/compiler.h>
 #include <linux/binfmts.h>
 #include <linux/threads.h>
 #include <linux/kernel.h>
@@ -42,6 +43,7 @@
 #define CLONE_VFORK    0x00004000      /* set if the parent wants the child to wake it up on mm_release */
 #define CLONE_PARENT   0x00008000      /* set if we want to have the same parent as the cloner */
 #define CLONE_THREAD   0x00010000      /* Same thread group? */
+#define CLONE_NEWNS    0x00020000      /* New namespace group? */
 
 #define CLONE_SIGNAL   (CLONE_SIGHAND | CLONE_THREAD)
 
@@ -72,8 +74,9 @@
 #define CT_TO_SECS(x)  ((x) / HZ)
 #define CT_TO_USECS(x) (((x) % HZ) * 1000000/HZ)
 
-extern int nr_running, nr_threads;
+extern int nr_threads;
 extern int last_pid;
+extern unsigned long nr_running(void);
 
 #include <linux/fs.h>
 #include <linux/time.h>
@@ -116,12 +119,6 @@
 #define SCHED_FIFO             1
 #define SCHED_RR               2
 
-/*
- * This is an additional bit set when we want to
- * yield the CPU for one re-schedule..
- */
-#define SCHED_YIELD            0x10
-
 struct sched_param {
        int sched_priority;
 };
@@ -139,17 +136,22 @@
  * a separate lock).
  */
 extern rwlock_t tasklist_lock;
-extern spinlock_t runqueue_lock;
 extern spinlock_t mmlist_lock;
 
+typedef struct task_struct task_t;
+
 extern void sched_init(void);
-extern void init_idle(void);
+extern void init_idle(task_t *idle, int cpu);
 extern void show_state(void);
 extern void cpu_init (void);
 extern void trap_init(void);
 extern void update_process_times(int user);
-extern void update_one_process(struct task_struct *p, unsigned long user,
+extern void update_one_process(task_t *p, unsigned long user,
                               unsigned long system, int cpu);
+extern void scheduler_tick(task_t *p);
+extern void sched_task_migrated(task_t *p);
+extern void smp_migrate_task(int cpu, task_t *task);
+extern unsigned long cache_decay_ticks;
 
 #define        MAX_SCHEDULE_TIMEOUT    LONG_MAX
 extern signed long FASTCALL(schedule_timeout(signed long timeout));
@@ -166,6 +168,7 @@
  */
 #define NR_OPEN_DEFAULT BITS_PER_LONG
 
+struct namespace;
 /*
  * Open file table structure
  */
@@ -278,6 +281,8 @@
 extern struct user_struct root_user;
 #define INIT_USER (&root_user)
 
+typedef struct prio_array prio_array_t;
+
 struct task_struct {
        /*
         * offsets of these are hardcoded elsewhere - touch with care
@@ -295,35 +300,28 @@
 
        int lock_depth;         /* Lock depth */
 
-/*
- * offset 32 begins here on 32-bit platforms. We keep
- * all fields in a single cacheline that are needed for
- * the goodness() loop in schedule().
- */
-       long counter;
-       long nice;
-       unsigned long policy;
-       struct mm_struct *mm;
-       int processor;
        /*
-        * cpus_runnable is ~0 if the process is not running on any
-        * CPU. It's (1 << cpu) if it's running on a CPU. This mask
-        * is updated under the runqueue lock.
-        *
-        * To determine whether a process might run on a CPU, this
-        * mask is AND-ed with cpus_allowed.
+        * offset 32 begins here on 32-bit platforms.
         */
-       unsigned long cpus_runnable, cpus_allowed;
-       /*
-        * (only the 'next' pointer fits into the cacheline, but
-        * that's just fine.)
-        */
-       struct list_head run_list;
-       unsigned long sleep_time;
+       unsigned int cpu;
+       int prio;
+       long __nice;
+       list_t run_list;
+       prio_array_t *array;
+
+       unsigned int time_slice;
 
-       struct task_struct *next_task, *prev_task;
-       struct mm_struct *active_mm;
+       unsigned long sleep_avg;
+       unsigned long sleep_timestamp;
+
+       unsigned long policy;
+       unsigned long cpus_allowed;
+
+       task_t *next_task, *prev_task;
+
+       struct mm_struct *mm, *active_mm;
        struct list_head local_pages;
+
        unsigned int allocation_order, nr_local_pages;
 
 /* task state */
@@ -345,12 +343,12 @@
         * older sibling, respectively.  (p->father can be replaced with 
         * p->p_pptr->pid)
         */
-       struct task_struct *p_opptr, *p_pptr, *p_cptr, *p_ysptr, *p_osptr;
+       task_t *p_opptr, *p_pptr, *p_cptr, *p_ysptr, *p_osptr;
        struct list_head thread_group;
 
        /* PID hash table linkage. */
-       struct task_struct *pidhash_next;
-       struct task_struct **pidhash_pprev;
+       task_t *pidhash_next;
+       task_t **pidhash_pprev;
 
        wait_queue_head_t wait_chldexit;        /* for wait4() */
        struct completion *vfork_done;          /* for vfork() */
@@ -389,6 +387,8 @@
        struct fs_struct *fs;
 /* open file information */
        struct files_struct *files;
+/* namespace */
+       struct namespace *namespace;
 /* signal handlers */
        spinlock_t sigmask_lock;        /* Protects signal and blocked */
        struct signal_struct *sig;
@@ -446,10 +446,66 @@
  */
 #define _STK_LIM       (8*1024*1024)
 
-#define DEF_COUNTER    (10*HZ/100)     /* 100 ms time slice */
-#define MAX_COUNTER    (20*HZ/100)
-#define DEF_NICE       (0)
+/*
+ * RT priorites go from 0 to 99, but internally we max
+ * them out at 128 to make it easier to search the
+ * scheduler bitmap.
+ */
+#define MAX_RT_PRIO            128
+/*
+ * The lower the priority of a process, the more likely it is
+ * to run. Priority of a process goes from 0 to 167. The 0-99
+ * priority range is allocated to RT tasks, the 128-167 range
+ * is for SCHED_OTHER tasks.
+ */
+#define MAX_PRIO               (MAX_RT_PRIO + 40)
+
+/*
+ * Scales user-nice values [ -20 ... 0 ... 19 ]
+ * to static priority [ 128 ... 167 (MAX_PRIO-1) ]
+ *
+ * User-nice value of -20 == static priority 128, and
+ * user-nice value 19 == static priority 167. The lower
+ * the priority value, the higher the task's priority.
+ */
+#define NICE_TO_PRIO(n)                (MAX_RT_PRIO + (n) + 20)
+#define DEF_USER_NICE          0
+
+/*
+ * Default timeslice is 250 msecs, maximum is 500 msecs.
+ * Minimum timeslice is 10 msecs.
+ */
+#define MIN_TIMESLICE          ( 10 * HZ / 1000)
+#define MAX_TIMESLICE           (300 * HZ / 1000)
+#define CHILD_FORK_PENALTY      95
+#define PARENT_FORK_PENALTY     100
+#define EXIT_WEIGHT             3
+#define PRIO_INTERACTIVE_RATIO  20
+#define PRIO_CPU_HOG_RATIO      60
+#define PRIO_BONUS_RATIO        70
+#define INTERACTIVE_DELTA       3
+#define MAX_SLEEP_AVG           (2*HZ)
+#define STARVATION_LIMIT        (2*HZ)
+
+#define USER_PRIO(p)           ((p)-MAX_RT_PRIO)
+#define MAX_USER_PRIO          (USER_PRIO(MAX_PRIO))
+
+/*
+ * NICE_TO_TIMESLICE scales nice values [ -20 ... 19 ]
+ * to time slice values.
+ *
+ * The higher a process's priority, the bigger timeslices
+ * it gets during one round of execution. But even the lowest
+ * priority process gets MIN_TIMESLICE worth of execution time.
+ */
 
+#define NICE_TO_TIMESLICE(n) (MIN_TIMESLICE + \
+       ((MAX_TIMESLICE - MIN_TIMESLICE) * (19-(n))) / 39)
+
+extern void set_cpus_allowed(task_t *p, unsigned long new_mask);
+extern void set_user_nice(task_t *p, long nice);
+asmlinkage long sys_sched_yield(void);
+#define yield() sys_sched_yield()
 
 /*
  * The default (Linux) execution domain.
@@ -468,14 +524,13 @@
     addr_limit:                KERNEL_DS,                                      \
     exec_domain:       &default_exec_domain,                           \
     lock_depth:                -1,                                             \
-    counter:           DEF_COUNTER,                                    \
-    nice:              DEF_NICE,                                       \
+    __nice:            DEF_USER_NICE,                                  \
     policy:            SCHED_OTHER,                                    \
+    cpus_allowed:      -1,                                             \
     mm:                        NULL,                                           \
     active_mm:         &init_mm,                                       \
-    cpus_runnable:     -1,                                             \
-    cpus_allowed:      -1,                                             \
     run_list:          LIST_HEAD_INIT(tsk.run_list),                   \
+    time_slice:                HZ,                                             \
     next_task:         &tsk,                                           \
     prev_task:         &tsk,                                           \
     p_opptr:           &tsk,                                           \
@@ -509,24 +564,24 @@
 #endif
 
 union task_union {
-       struct task_struct task;
+       task_t task;
        unsigned long stack[INIT_TASK_SIZE/sizeof(long)];
 };
 
 extern union task_union init_task_union;
 
 extern struct   mm_struct init_mm;
-extern struct task_struct *init_tasks[NR_CPUS];
+extern task_t *init_tasks[NR_CPUS];
 
 /* PID hashing. (shouldnt this be dynamic?) */
 #define PIDHASH_SZ (4096 >> 2)
-extern struct task_struct *pidhash[PIDHASH_SZ];
+extern task_t *pidhash[PIDHASH_SZ];
 
 #define pid_hashfn(x)  ((((x) >> 8) ^ (x)) & (PIDHASH_SZ - 1))
 
-static inline void hash_pid(struct task_struct *p)
+static inline void hash_pid(task_t *p)
 {
-       struct task_struct **htable = &pidhash[pid_hashfn(p->pid)];
+       task_t **htable = &pidhash[pid_hashfn(p->pid)];
 
        if((p->pidhash_next = *htable) != NULL)
                (*htable)->pidhash_pprev = &p->pidhash_next;
@@ -534,16 +589,16 @@
        p->pidhash_pprev = htable;
 }
 
-static inline void unhash_pid(struct task_struct *p)
+static inline void unhash_pid(task_t *p)
 {
        if(p->pidhash_next)
                p->pidhash_next->pidhash_pprev = p->pidhash_pprev;
        *p->pidhash_pprev = p->pidhash_next;
 }
 
-static inline struct task_struct *find_task_by_pid(int pid)
+static inline task_t *find_task_by_pid(int pid)
 {
-       struct task_struct *p, **htable = &pidhash[pid_hashfn(pid)];
+       task_t *p, **htable = &pidhash[pid_hashfn(pid)];
 
        for(p = *htable; p && p->pid != pid; p = p->pidhash_next)
                ;
@@ -551,19 +606,6 @@
        return p;
 }
 
-#define task_has_cpu(tsk) ((tsk)->cpus_runnable != ~0UL)
-
-static inline void task_set_cpu(struct task_struct *tsk, unsigned int cpu)
-{
-       tsk->processor = cpu;
-       tsk->cpus_runnable = 1UL << cpu;
-}
-
-static inline void task_release_cpu(struct task_struct *tsk)
-{
-       tsk->cpus_runnable = ~0UL;
-}
-
 /* per-UID process charging. */
 extern struct user_struct * alloc_uid(uid_t);
 extern void free_uid(struct user_struct *);
@@ -590,7 +632,8 @@
 extern void FASTCALL(interruptible_sleep_on(wait_queue_head_t *q));
 extern long FASTCALL(interruptible_sleep_on_timeout(wait_queue_head_t *q,
                                                    signed long timeout));
-extern int FASTCALL(wake_up_process(struct task_struct * tsk));
+extern int FASTCALL(wake_up_process(task_t * tsk));
+extern void FASTCALL(wake_up_forked_process(task_t * tsk));
 
 #define wake_up(x)                     __wake_up((x),TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 1)
 #define wake_up_nr(x, nr)              __wake_up((x),TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, nr)
@@ -608,28 +651,28 @@
 extern int in_egroup_p(gid_t);
 
 extern void proc_caches_init(void);
-extern void flush_signals(struct task_struct *);
-extern void flush_signal_handlers(struct task_struct *);
+extern void flush_signals(task_t *);
+extern void flush_signal_handlers(task_t *);
 extern int dequeue_signal(sigset_t *, siginfo_t *);
 extern void block_all_signals(int (*notifier)(void *priv), void *priv,
                              sigset_t *mask);
 extern void unblock_all_signals(void);
-extern int send_sig_info(int, struct siginfo *, struct task_struct *);
-extern int force_sig_info(int, struct siginfo *, struct task_struct *);
+extern int send_sig_info(int, struct siginfo *, task_t *);
+extern int force_sig_info(int, struct siginfo *, task_t *);
 extern int kill_pg_info(int, struct siginfo *, pid_t);
 extern int kill_sl_info(int, struct siginfo *, pid_t);
 extern int kill_proc_info(int, struct siginfo *, pid_t);
-extern void notify_parent(struct task_struct *, int);
-extern void do_notify_parent(struct task_struct *, int);
-extern void force_sig(int, struct task_struct *);
-extern int send_sig(int, struct task_struct *, int);
+extern void notify_parent(task_t *, int);
+extern void do_notify_parent(task_t *, int);
+extern void force_sig(int, task_t *);
+extern int send_sig(int, task_t *, int);
 extern int kill_pg(pid_t, int, int);
 extern int kill_sl(pid_t, int, int);
 extern int kill_proc(pid_t, int, int);
 extern int do_sigaction(int, const struct k_sigaction *, struct k_sigaction *);
 extern int do_sigaltstack(const stack_t *, stack_t *, unsigned long);
 
-static inline int signal_pending(struct task_struct *p)
+static inline int signal_pending(task_t *p)
 {
        return (p->sigpending != 0);
 }
@@ -668,7 +711,7 @@
    This is required every time the blocked sigset_t changes.
    All callers should have t->sigmask_lock.  */
 
-static inline void recalc_sigpending(struct task_struct *t)
+static inline void recalc_sigpending(task_t *t)
 {
        t->sigpending = has_pending_signals(&t->pending.signal, &t->blocked);
 }
@@ -775,16 +818,17 @@
 extern int expand_fdset(struct files_struct *, int nr);
 extern void free_fdset(fd_set *, int);
 
-extern int  copy_thread(int, unsigned long, unsigned long, unsigned long, struct task_struct *, struct pt_regs *);
+extern int  copy_thread(int, unsigned long, unsigned long, unsigned long, task_t *, struct pt_regs *);
 extern void flush_thread(void);
 extern void exit_thread(void);
 
-extern void exit_mm(struct task_struct *);
-extern void exit_files(struct task_struct *);
-extern void exit_sighand(struct task_struct *);
+extern void exit_mm(task_t *);
+extern void exit_files(task_t *);
+extern void exit_sighand(task_t *);
 
 extern void reparent_to_init(void);
 extern void daemonize(void);
+extern task_t *child_reaper;
 
 extern int do_execve(char *, char **, char **, struct pt_regs *);
 extern int do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long);
@@ -793,6 +837,9 @@
 extern void FASTCALL(add_wait_queue_exclusive(wait_queue_head_t *q, wait_queue_t * wait));
 extern void FASTCALL(remove_wait_queue(wait_queue_head_t *q, wait_queue_t * wait));
 
+extern void wait_task_inactive(task_t * p);
+extern void kick_if_running(task_t * p);
+
 #define __wait_event(wq, condition)                                    \
 do {                                                                   \
        wait_queue_t __wait;                                            \
@@ -871,24 +918,10 @@
        for (p = &init_task ; (p = p->next_task) != &init_task ; )
 
 #define next_thread(p) \
-       list_entry((p)->thread_group.next, struct task_struct, thread_group)
-
-static inline void del_from_runqueue(struct task_struct * p)
-{
-       nr_running--;
-       p->sleep_time = jiffies;
-       list_del(&p->run_list);
-       p->run_list.next = NULL;
-}
-
-static inline int task_on_runqueue(struct task_struct *p)
-{
-       return (p->run_list.next != NULL);
-}
+       list_entry((p)->thread_group.next, task_t, thread_group)
 
-static inline void unhash_process(struct task_struct *p)
+static inline void unhash_process(task_t *p)
 {
-       if (task_on_runqueue(p)) BUG();
        write_lock_irq(&tasklist_lock);
        nr_threads--;
        unhash_pid(p);
@@ -898,12 +931,12 @@
 }
 
 /* Protects ->fs, ->files, ->mm, and synchronises with wait4().  Nests inside tasklist_lock */
-static inline void task_lock(struct task_struct *p)
+static inline void task_lock(task_t *p)
 {
        spin_lock(&p->alloc_lock);
 }
 
-static inline void task_unlock(struct task_struct *p)
+static inline void task_unlock(task_t *p)
 {
        spin_unlock(&p->alloc_lock);
 }
--- linux/include/linux/list.h.orig     Sun Jan  6 13:55:57 2002
+++ linux/include/linux/list.h  Mon Jan 28 18:48:00 2002
@@ -19,6 +19,8 @@
        struct list_head *next, *prev;
 };
 
+typedef struct list_head list_t;
+
 #define LIST_HEAD_INIT(name) { &(name), &(name) }
 
 #define LIST_HEAD(name) \
--- linux/include/linux/kernel_stat.h.orig      Tue Aug 21 14:26:23 2001
+++ linux/include/linux/kernel_stat.h   Mon Jan 28 18:48:00 2002
@@ -32,10 +32,11 @@
        unsigned int ipackets, opackets;
        unsigned int ierrors, oerrors;
        unsigned int collisions;
-       unsigned int context_swtch;
 };
 
 extern struct kernel_stat kstat;
+
+extern unsigned long nr_context_switches(void);
 
 #if !defined(CONFIG_ARCH_S390)
 /*
--- linux/include/linux/smp.h.orig      Sun Dec 31 20:10:17 2000
+++ linux/include/linux/smp.h   Mon Jan 28 18:48:00 2002
@@ -86,6 +86,14 @@
 #define cpu_number_map(cpu)                    0
 #define smp_call_function(func,info,retry,wait)        ({ 0; })
 #define cpu_online_map                         1
+static inline void smp_send_reschedule(int cpu) { }
+static inline void smp_send_reschedule_all(void) { }
 
 #endif
+
+/*
+ * Common definitions:
+ */
+#define cpu()                                  smp_processor_id()
+
 #endif
--- linux/include/asm-i386/smp.h.orig   Sun Jan  6 13:55:57 2002
+++ linux/include/asm-i386/smp.h        Mon Jan 28 18:48:00 2002
@@ -63,6 +63,7 @@
 extern void smp_flush_tlb(void);
 extern void smp_message_irq(int cpl, void *dev_id, struct pt_regs *regs);
 extern void smp_send_reschedule(int cpu);
+extern void smp_send_reschedule_all(void);
 extern void smp_invalidate_rcv(void);          /* Process an NMI */
 extern void (*mtrr_hook) (void);
 extern void zap_low_mappings (void);
@@ -104,7 +105,7 @@
  * so this is correct in the x86 case.
  */
 
-#define smp_processor_id() (current->processor)
+#define smp_processor_id() (current->cpu)
 
 static __inline int hard_smp_processor_id(void)
 {
@@ -121,18 +122,6 @@
 #endif /* !__ASSEMBLY__ */
 
 #define NO_PROC_ID             0xFF            /* No processor magic marker */
-
-/*
- *     This magic constant controls our willingness to transfer
- *     a process across CPUs. Such a transfer incurs misses on the L1
- *     cache, and on a P6 or P5 with multiple L2 caches L2 hits. My
- *     gut feeling is this will vary by board in value. For a board
- *     with separate L2 cache it probably depends also on the RSS, and
- *     for a board with shared L2 cache it ought to decay fast as other
- *     processes are run.
- */
- 
-#define PROC_CHANGE_PENALTY    15              /* Schedule penalty */
 
 #endif
 #endif
--- linux/include/asm-i386/bitops.h.orig        Tue Aug 21 14:26:16 2001
+++ linux/include/asm-i386/bitops.h     Mon Jan 28 18:48:00 2002
@@ -75,6 +75,14 @@
                :"=m" (ADDR)
                :"Ir" (nr));
 }
+
+static __inline__ void __clear_bit(int nr, volatile void * addr)
+{
+       __asm__ __volatile__(
+               "btrl %1,%0"
+               :"=m" (ADDR)
+               :"Ir" (nr));
+}
 #define smp_mb__before_clear_bit()     barrier()
 #define smp_mb__after_clear_bit()      barrier()
 
@@ -284,6 +292,34 @@
 }
 
 /**
+ * find_first_bit - find the first set bit in a memory region
+ * @addr: The address to start the search at
+ * @size: The maximum size to search
+ *
+ * Returns the bit-number of the first set bit, not the number of the byte
+ * containing a bit.
+ */
+static __inline__ int find_first_bit(void * addr, unsigned size)
+{
+       int d0, d1;
+       int res;
+
+       /* This looks at memory. Mark it volatile to tell gcc not to move it around */
+       __asm__ __volatile__(
+               "xorl %%eax,%%eax\n\t"
+               "repe; scasl\n\t"
+               "jz 1f\n\t"
+               "leal -4(%%edi),%%edi\n\t"
+               "bsfl (%%edi),%%eax\n"
+               "1:\tsubl %%ebx,%%edi\n\t"
+               "shll $3,%%edi\n\t"
+               "addl %%edi,%%eax"
+               :"=a" (res), "=&c" (d0), "=&D" (d1)
+               :"1" ((size + 31) >> 5), "2" (addr), "b" (addr));
+       return res;
+}
+
+/**
  * find_next_zero_bit - find the first zero bit in a memory region
  * @addr: The address to base the search on
  * @offset: The bitnumber to start searching at
@@ -296,7 +332,7 @@
        
        if (bit) {
                /*
-                * Look for zero in first byte
+                * Look for zero in the first 32 bits.
                 */
                __asm__("bsfl %1,%0\n\t"
                        "jne 1f\n\t"
@@ -317,6 +353,39 @@
 }
 
 /**
+ * find_next_bit - find the first set bit in a memory region
+ * @addr: The address to base the search on
+ * @offset: The bitnumber to start searching at
+ * @size: The maximum size to search
+ */
+static __inline__ int find_next_bit (void * addr, int size, int offset)
+{
+       unsigned long * p = ((unsigned long *) addr) + (offset >> 5);
+       int set = 0, bit = offset & 31, res;
+       
+       if (bit) {
+               /*
+                * Look for nonzero in the first 32 bits:
+                */
+               __asm__("bsfl %1,%0\n\t"
+                       "jne 1f\n\t"
+                       "movl $32, %0\n"
+                       "1:"
+                       : "=r" (set)
+                       : "r" (*p >> bit));
+               if (set < (32 - bit))
+                       return set + offset;
+               set = 32 - bit;
+               p++;
+       }
+       /*
+        * No set bit yet, search remaining full words for a bit
+        */
+       res = find_first_bit (p, size - 32 * (p - (unsigned long *) addr));
+       return (offset + set + res);
+}
+
+/**
  * ffz - find first zero in word.
  * @word: The word to search
  *
@@ -327,6 +396,20 @@
        __asm__("bsfl %1,%0"
                :"=r" (word)
                :"r" (~word));
+       return word;
+}
+
+/**
+ * __ffs - find first bit in word.
+ * @word: The word to search
+ *
+ * Undefined if no bit exists, so code should check against 0 first.
+ */
+static __inline__ unsigned long __ffs(unsigned long word)
+{
+       __asm__("bsfl %1,%0"
+               :"=r" (word)
+               :"rm" (word));
        return word;
 }
 
--- linux/include/asm-i386/pgalloc.h.orig       Sun Jan  6 13:55:57 2002
+++ linux/include/asm-i386/pgalloc.h    Mon Jan 28 18:48:00 2002
@@ -224,6 +224,7 @@
 {
        struct mm_struct *active_mm;
        int state;
+       char __cacheline_padding[24];
 };
 extern struct tlb_state cpu_tlbstate[NR_CPUS];
 
--- linux/include/asm-i386/mmu_context.h.orig   Tue Aug 21 14:26:23 2001
+++ linux/include/asm-i386/mmu_context.h        Mon Jan 28 18:48:00 2002
@@ -7,6 +7,31 @@
 #include <asm/pgalloc.h>
 
 /*
+ * Every architecture must define this function. It's the fastest
+ * way of searching a 168-bit bitmap where the first 128 bits are
+ * unlikely to be set. It's guaranteed that at least one of the 168
+ * bits is cleared.
+ */
+#if MAX_RT_PRIO != 128 || MAX_PRIO != 168
+# error update this function.
+#endif
+
+static inline int sched_find_first_bit(unsigned long *b)
+{
+       if (unlikely(b[0]))
+               return __ffs(b[0]);
+       if (unlikely(b[1]))
+               return __ffs(b[1]) + 32;
+       if (unlikely(b[2]))
+               return __ffs(b[2]) + 64;
+       if (unlikely(b[3]))
+               return __ffs(b[3]) + 96;
+       if (b[4])
+               return __ffs(b[4]) + 128;
+       return __ffs(b[5]) + 32 + 128;
+}
+
+/*
  * possibly do the LDT unload here?
  */
 #define destroy_context(mm)            do { } while(0)
@@ -27,13 +52,13 @@
 
 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, struct task_struct *tsk, unsigned cpu)
 {
-       if (prev != next) {
+       if (likely(prev != next)) {
                /* stop flush ipis for the previous mm */
                clear_bit(cpu, &prev->cpu_vm_mask);
                /*
                 * Re-load LDT if necessary
                 */
-               if (prev->context.segments != next->context.segments)
+               if (unlikely(prev->context.segments != next->context.segments))
                        load_LDT(next);
 #ifdef CONFIG_SMP
                cpu_tlbstate[cpu].state = TLBSTATE_OK;
--- linux/include/asm-i386/hw_irq.h.orig        Wed Jan 16 21:44:01 2002
+++ linux/include/asm-i386/hw_irq.h     Mon Jan 28 18:48:00 2002
@@ -41,8 +41,9 @@
 #define ERROR_APIC_VECTOR      0xfe
 #define INVALIDATE_TLB_VECTOR  0xfd
 #define RESCHEDULE_VECTOR      0xfc
-#define CALL_FUNCTION_VECTOR   0xfb
-#define KDB_VECTOR             0xfa
+#define TASK_MIGRATION_VECTOR  0xfb
+#define CALL_FUNCTION_VECTOR   0xfa
+#define KDB_VECTOR             0xf9
 
 /*
  * Local APIC timer IRQ vector is on a different priority level,
--- linux/include/asm-i386/apic.h.orig  Mon Jan 28 18:05:10 2002
+++ linux/include/asm-i386/apic.h       Mon Jan 28 18:48:00 2002
@@ -79,6 +79,8 @@
 extern void setup_apic_nmi_watchdog (void);
 extern inline void nmi_watchdog_tick (struct pt_regs * regs);
 extern int APIC_init_uniprocessor (void);
+extern void disable_APIC_timer(void);
+extern void enable_APIC_timer(void);
 
 extern struct pm_dev *apic_pm_register(pm_dev_t, unsigned long, pm_callback);
 extern void apic_pm_unregister(struct pm_dev*);
--- linux/net/unix/af_unix.c.orig       Sun Jan  6 13:55:58 2002
+++ linux/net/unix/af_unix.c    Sun Jan  6 13:56:25 2002
@@ -564,10 +564,8 @@
                                      addr->hash)) {
                write_unlock(&unix_table_lock);
                /* Sanity yield. It is unusual case, but yet... */
-               if (!(ordernum&0xFF)) {
-                       current->policy |= SCHED_YIELD;
-                       schedule();
-               }
+               if (!(ordernum&0xFF))
+                       yield();
                goto retry;
        }
        addr->hash ^= sk->type;
--- linux/net/ipv4/tcp_output.c.orig    Sun Jan  6 13:55:57 2002
+++ linux/net/ipv4/tcp_output.c Sun Jan  6 13:56:25 2002
@@ -1009,8 +1009,7 @@
                        skb = alloc_skb(MAX_TCP_HEADER, GFP_KERNEL);
                        if (skb)
                                break;
-                       current->policy |= SCHED_YIELD;
-                       schedule();
+                       yield();
                }
 
                /* Reserve space for headers and prepare control bits. */
--- linux/net/sunrpc/sched.c.orig       Sun Jan  6 13:55:52 2002
+++ linux/net/sunrpc/sched.c    Sun Jan  6 13:56:25 2002
@@ -772,8 +772,7 @@
                }
                if (flags & RPC_TASK_ASYNC)
                        return NULL;
-               current->policy |= SCHED_YIELD;
-               schedule();
+               yield();
        } while (!signalled());
 
        return NULL;
@@ -1114,8 +1113,7 @@
                __rpc_schedule();
                if (all_tasks) {
                        dprintk("rpciod_killall: waiting for tasks to exit\n");
-                       current->policy |= SCHED_YIELD;
-                       schedule();
+                       yield();
                }
        }
 
@@ -1185,8 +1183,7 @@
         * wait briefly before checking the process id.
         */
        current->sigpending = 0;
-       current->policy |= SCHED_YIELD;
-       schedule();
+       yield();
        /*
         * Display a message if we're going to wait longer.
         */
--- linux/net/sched/sch_generic.c.orig  Fri Aug 18 19:26:25 2000
+++ linux/net/sched/sch_generic.c       Sun Jan  6 13:56:25 2002
@@ -475,10 +475,8 @@
 
        dev_watchdog_down(dev);
 
-       while (test_bit(__LINK_STATE_SCHED, &dev->state)) {
-               current->policy |= SCHED_YIELD;
-               schedule();
-       }
+       while (test_bit(__LINK_STATE_SCHED, &dev->state))
+               yield();
 
        spin_unlock_wait(&dev->xmit_lock);
 }
--- linux/net/socket.c.orig     Sun Jan  6 13:55:58 2002
+++ linux/net/socket.c  Sun Jan  6 13:56:25 2002
@@ -148,8 +148,7 @@
        while (atomic_read(&net_family_lockct) != 0) {
                spin_unlock(&net_family_lock);
 
-               current->policy |= SCHED_YIELD;
-               schedule();
+               yield();
 
                spin_lock(&net_family_lock);
        }
--- linux/drivers/net/slip.c.orig       Sun Jan  6 13:55:48 2002
+++ linux/drivers/net/slip.c    Sun Jan  6 13:56:25 2002
@@ -1393,10 +1393,8 @@
                /* First of all: check for active disciplines and hangup them.
                 */
                do {
-                       if (busy) {
-                               current->counter = 0;
-                               schedule();
-                       }
+                       if (busy)
+                               sys_sched_yield();
 
                        busy = 0;
                        local_bh_disable();
--- linux/drivers/block/loop.c.orig     Sun Jan  6 13:55:56 2002
+++ linux/drivers/block/loop.c  Sun Jan  6 13:56:25 2002
@@ -570,9 +570,6 @@
        flush_signals(current);
        spin_unlock_irq(&current->sigmask_lock);
 
-       current->policy = SCHED_OTHER;
-       current->nice = -20;
-
        spin_lock_irq(&lo->lo_lock);
        lo->lo_state = Lo_bound;
        atomic_inc(&lo->lo_pending);
--- linux/drivers/char/mwave/mwavedd.c.orig     Sun Jan 13 16:27:41 2002
+++ linux/drivers/char/mwave/mwavedd.c  Sun Jan 13 16:28:05 2002
@@ -279,7 +279,6 @@
                        pDrvData->IPCs[ipcnum].bIsHere = FALSE;
                        pDrvData->IPCs[ipcnum].bIsEnabled = TRUE;
        #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,0)
-                       current->nice = -20;    /* boost to provide priority timing */
        #else
                        current->priority = 0x28;       /* boost to provide priority timing */
        #endif
--- linux/drivers/ide/ataraid.c.orig    Sun Jan  6 13:55:52 2002
+++ linux/drivers/ide/ataraid.c Fri Jan 25 14:27:38 2002
@@ -123,8 +123,7 @@
                ptr=kmalloc(sizeof(struct buffer_head),GFP_NOIO);
                if (!ptr) {
                        __set_current_state(TASK_RUNNING);
-                       current->policy |= SCHED_YIELD;
-                       schedule();             
+                       yield();
                }
        }
        return ptr;
@@ -139,8 +138,7 @@
                ptr=kmalloc(sizeof(struct ataraid_bh_private),GFP_NOIO);
                if (!ptr) {
                        __set_current_state(TASK_RUNNING);
-                       current->policy |= SCHED_YIELD;
-                       schedule();             
+                       yield();
                }
        }
        return ptr;
--- linux/drivers/md/md.c.orig  Sun Jan  6 13:55:56 2002
+++ linux/drivers/md/md.c       Sun Jan  6 13:56:25 2002
@@ -2930,8 +2930,6 @@
         * bdflush, otherwise bdflush will deadlock if there are too
         * many dirty RAID5 blocks.
         */
-       current->policy = SCHED_OTHER;
-       current->nice = -20;
        md_unlock_kernel();
 
        complete(thread->event);
@@ -3381,11 +3379,6 @@
               "(but not more than %d KB/sec) for reconstruction.\n",
               sysctl_speed_limit_max);
 
-       /*
-        * Resync has low priority.
-        */
-       current->nice = 19;
-
        is_mddev_idle(mddev); /* this also initializes IO event counters */
        for (m = 0; m < SYNC_MARKS; m++) {
                mark[m] = jiffies;
@@ -3463,16 +3456,13 @@
                currspeed = (j-mddev->resync_mark_cnt)/2/((jiffies-mddev->resync_mark)/HZ +1) +1;
 
                if (currspeed > sysctl_speed_limit_min) {
-                       current->nice = 19;
-
                        if ((currspeed > sysctl_speed_limit_max) ||
                                        !is_mddev_idle(mddev)) {
                                current->state = TASK_INTERRUPTIBLE;
                                md_schedule_timeout(HZ/4);
                                goto repeat;
                        }
-               } else
-                       current->nice = -20;
+               }
        }
        printk(KERN_INFO "md: md%d: sync done.\n",mdidx(mddev));
        err = 0;
--- linux/arch/i386/mm/fault.c.orig     Sun Jan  6 13:55:47 2002
+++ linux/arch/i386/mm/fault.c  Sun Jan  6 13:56:25 2002
@@ -88,8 +88,7 @@
 
 out_of_memory:
        if (current->pid == 1) {
-               current->policy |= SCHED_YIELD;
-               schedule();
+               yield();
                goto survive;
        }
        goto bad_area;
@@ -344,8 +343,7 @@
 out_of_memory:
        up_read(&mm->mmap_sem);
        if (tsk->pid == 1) {
-               tsk->policy |= SCHED_YIELD;
-               schedule();
+               yield();
                down_read(&mm->mmap_sem);
                goto survive;
        }
--- linux/arch/i386/kernel/smpboot.c.orig       Sun Jan  6 13:55:56 2002
+++ linux/arch/i386/kernel/smpboot.c    Mon Jan 28 18:12:21 2002
@@ -308,14 +308,14 @@
                        if (tsc_values[i] < avg)
                                realdelta = -realdelta;
 
-                       printk("BIOS BUG: CPU#%d improperly initialized, has %ld usecs TSC skew! FIXED.\n",
-                               i, realdelta);
+                       printk("BIOS BUG: CPU#%d improperly initialized, has %ld usecs TSC skew! FIXED.\n", i, realdelta);
                }
 
                sum += delta;
        }
        if (!buggy)
                printk("passed.\n");
+               ;
 }
 
 static void __init synchronize_tsc_ap (void)
@@ -365,7 +365,7 @@
         * (This works even if the APIC is not enabled.)
         */
        phys_id = GET_APIC_ID(apic_read(APIC_ID));
-       cpuid = current->processor;
+       cpuid = cpu();
        if (test_and_set_bit(cpuid, &cpu_online_map)) {
                printk("huh, phys CPU#%d, CPU#%d already present??\n",
                                        phys_id, cpuid);
@@ -435,6 +435,7 @@
         */
        smp_store_cpu_info(cpuid);
 
+       disable_APIC_timer();
        /*
         * Allow the master to continue.
         */
@@ -465,6 +466,7 @@
        smp_callin();
        while (!atomic_read(&smp_commenced))
                rep_nop();
+       enable_APIC_timer();
        /*
         * low-memory mappings have been cleared, flush them from
         * the local TLBs too.
@@ -803,16 +805,13 @@
        if (!idle)
                panic("No idle process for CPU %d", cpu);
 
-       idle->processor = cpu;
-       idle->cpus_runnable = 1 << cpu; /* we schedule the first task manually */
+       init_idle(idle, cpu);
 
        map_cpu_to_boot_apicid(cpu, apicid);
 
        idle->thread.eip = (unsigned long) start_secondary;
 
-       del_from_runqueue(idle);
        unhash_process(idle);
-       init_tasks[cpu] = idle;
 
        /* start_eip had better be page-aligned! */
        start_eip = setup_trampoline();
@@ -925,6 +924,7 @@
 }
 
 cycles_t cacheflush_time;
+unsigned long cache_decay_ticks;
 
 static void smp_tune_scheduling (void)
 {
@@ -958,9 +958,13 @@
                cacheflush_time = (cpu_khz>>10) * (cachesize<<10) / bandwidth;
        }
 
+       cache_decay_ticks = (long)cacheflush_time/cpu_khz * HZ / 1000;
+
        printk("per-CPU timeslice cutoff: %ld.%02ld usecs.\n",
                (long)cacheflush_time/(cpu_khz/1000),
                ((long)cacheflush_time*100/(cpu_khz/1000)) % 100);
+       printk("task migration cache decay timeout: %ld msecs.\n",
+               (cache_decay_ticks + 1) * 1000 / HZ);
 }
 
 /*
@@ -1020,8 +1024,7 @@
        map_cpu_to_boot_apicid(0, boot_cpu_apicid);
 
        global_irq_holder = 0;
-       current->processor = 0;
-       init_idle();
+       current->cpu = 0;
        smp_tune_scheduling();
 
        /*
--- linux/arch/i386/kernel/process.c.orig       Mon Jan 28 18:09:58 2002
+++ linux/arch/i386/kernel/process.c    Mon Jan 28 18:09:53 2002
@@ -123,15 +123,12 @@
 void cpu_idle (void)
 {
        /* endless idle loop with no priority at all */
-       init_idle();
-       current->nice = 20;
-       current->counter = -100;
 
        while (1) {
                void (*idle)(void) = pm_idle;
                if (!idle)
                        idle = default_idle;
-               while (!current->need_resched)
+               if (!current->need_resched)
                        idle();
                schedule();
                check_pgt_cache();
@@ -694,15 +691,17 @@
        asm volatile("movl %%gs,%0":"=m" (*(int *)&prev->gs));
 
        /*
-        * Restore %fs and %gs.
+        * Restore %fs and %gs if needed.
         */
-       loadsegment(fs, next->fs);
-       loadsegment(gs, next->gs);
+       if (unlikely(prev->fs | prev->gs | next->fs | next->gs)) {
+               loadsegment(fs, next->fs);
+               loadsegment(gs, next->gs);
+       }
 
        /*
         * Now maybe reload the debug registers
         */
-       if (next->debugreg[7]){
+       if (unlikely(next->debugreg[7])) {
                loaddebug(next, 0);
                loaddebug(next, 1);
                loaddebug(next, 2);
@@ -712,7 +711,7 @@
                loaddebug(next, 7);
        }
 
-       if (prev->ioperm || next->ioperm) {
+       if (unlikely(prev->ioperm || next->ioperm)) {
                if (next->ioperm) {
                        /*
                         * 4 cachelines copy ... not good, but not that
--- linux/arch/i386/kernel/apic.c.orig  Sun Jan  6 13:55:54 2002
+++ linux/arch/i386/kernel/apic.c       Mon Jan 28 18:07:11 2002
@@ -785,8 +785,7 @@
         */
 
        slice = clocks / (smp_num_cpus+1);
-       printk("cpu: %d, clocks: %d, slice: %d\n",
-               smp_processor_id(), clocks, slice);
+       printk("cpu: %d, clocks: %d, slice: %d\n", smp_processor_id(), clocks, slice);
 
        /*
         * Wait for IRQ0's slice:
@@ -809,8 +808,7 @@
 
        __setup_APIC_LVTT(clocks);
 
-       printk("CPU%d<T0:%d,T1:%d,D:%d,S:%d,C:%d>\n",
-                       smp_processor_id(), t0, t1, delta, slice, clocks);
+       printk("CPU%d<T0:%d,T1:%d,D:%d,S:%d,C:%d>\n", smp_processor_id(), t0, t1, delta, slice, clocks);
 
        __restore_flags(flags);
 }
@@ -911,6 +909,26 @@
 
        /* and update all other cpus */
        smp_call_function(setup_APIC_timer, (void *)calibration_result, 1, 1);
+}
+
+void __init disable_APIC_timer(void)
+{
+       if (using_apic_timer) {
+               unsigned long v;
+
+               v = apic_read(APIC_LVTT);
+               apic_write_around(APIC_LVTT, v | APIC_LVT_MASKED);
+       }
+}
+
+void enable_APIC_timer(void)
+{
+       if (using_apic_timer) {
+               unsigned long v;
+
+               v = apic_read(APIC_LVTT);
+               apic_write_around(APIC_LVTT, v & ~APIC_LVT_MASKED);
+       }
 }
 
 /*
--- linux/arch/i386/kernel/nmi.c.orig   Sun Jan  6 13:55:43 2002
+++ linux/arch/i386/kernel/nmi.c        Sun Jan  6 13:56:25 2002
@@ -283,7 +283,7 @@
                         * to get a message out.
                         */
                        bust_spinlocks(1);
-                       printk("NMI Watchdog detected LOCKUP on CPU%d, registers:\n", cpu);
+                       printk("NMI Watchdog detected LOCKUP on CPU%d, eip %08lx, registers:\n", cpu, regs->eip);
                        show_registers(regs);
                        printk("console shuts up ...\n");
                        console_silent();
--- linux/arch/i386/kernel/smp.c.orig   Sun Jan  6 13:55:56 2002
+++ linux/arch/i386/kernel/smp.c        Wed Jan 16 21:42:45 2002
@@ -105,7 +105,7 @@
 /* The 'big kernel lock' */
 spinlock_t kernel_flag __cacheline_aligned_in_smp = SPIN_LOCK_UNLOCKED;
 
-struct tlb_state cpu_tlbstate[NR_CPUS] = {[0 ... NR_CPUS-1] = { &init_mm, 0 }};
+struct tlb_state cpu_tlbstate[NR_CPUS] __cacheline_aligned = {[0 ... NR_CPUS-1] = { &init_mm, 0, }};
 
 /*
  * the following functions deal with sending IPIs between CPUs.
@@ -485,15 +485,54 @@
        do_flush_tlb_all_local();
 }
 
+static spinlock_t migration_lock = SPIN_LOCK_UNLOCKED;
+static task_t *new_task;
+
+/*
+ * This function sends a 'task migration' IPI to another CPU.
+ * Must be called from syscall contexts, with interrupts *enabled*.
+ */
+void smp_migrate_task(int cpu, task_t *p)
+{
+       /*
+        * The target CPU will unlock the migration spinlock:
+        */
+       spin_lock(&migration_lock);
+       new_task = p;
+       send_IPI_mask(1 << cpu, TASK_MIGRATION_VECTOR);
+}
+
+/*
+ * Task migration callback.
+ */
+asmlinkage void smp_task_migration_interrupt(void)
+{
+       task_t *p;
+
+       ack_APIC_irq();
+       p = new_task;
+       spin_unlock(&migration_lock);
+       sched_task_migrated(p);
+}
 /*
  * this function sends a 'reschedule' IPI to another CPU.
  * it goes straight through and wastes no time serializing
  * anything. Worst case is that we lose a reschedule ...
  */
-
 void smp_send_reschedule(int cpu)
 {
        send_IPI_mask(1 << cpu, RESCHEDULE_VECTOR);
+}
+
+/*
+ * this function sends a reschedule IPI to all (other) CPUs.
+ * This should only be used if some 'global' task became runnable,
+ * such as a RT task, that must be handled now. The first CPU
+ * that manages to grab the task will run it.
+ */
+void smp_send_reschedule_all(void)
+{
+       send_IPI_allbutself(RESCHEDULE_VECTOR);
 }
 
 /*
--- linux/arch/i386/kernel/i8259.c.orig Wed Jan 16 21:43:09 2002
+++ linux/arch/i386/kernel/i8259.c      Fri Jan 18 15:36:35 2002
@@ -79,6 +79,7 @@
  * through the ICC by us (IPIs)
  */
 #ifdef CONFIG_SMP
+BUILD_SMP_INTERRUPT(task_migration_interrupt,TASK_MIGRATION_VECTOR)
 BUILD_SMP_INTERRUPT(reschedule_interrupt,RESCHEDULE_VECTOR)
 BUILD_SMP_INTERRUPT(invalidate_interrupt,INVALIDATE_TLB_VECTOR)
 BUILD_SMP_INTERRUPT(call_function_interrupt,CALL_FUNCTION_VECTOR)
@@ -472,6 +473,9 @@
         * IPI, driven by wakeup.
         */
        set_intr_gate(RESCHEDULE_VECTOR, reschedule_interrupt);
+
+       /* IPI for task migration */
+       set_intr_gate(TASK_MIGRATION_VECTOR, task_migration_interrupt);
 
        /* IPI for invalidation */
        set_intr_gate(INVALIDATE_TLB_VECTOR, invalidate_interrupt);
--- linux/arch/i386/kernel/entry.S.orig Fri Jan 25 14:30:36 2002
+++ linux/arch/i386/kernel/entry.S      Fri Jan 25 14:30:50 2002
@@ -77,7 +77,7 @@
 exec_domain    = 16
 need_resched   = 20
 tsk_ptrace     = 24
-processor      = 52
+cpu            = 32
 
 ENOSYS = 38
 
--- linux/arch/i386/kernel/setup.c.orig Mon Jan 28 18:10:23 2002
+++ linux/arch/i386/kernel/setup.c      Mon Jan 28 18:10:48 2002
@@ -2922,9 +2922,10 @@
        load_TR(nr);
        load_LDT(&init_mm);
 
-       /*
-        * Clear all 6 debug registers:
-        */
+       /* Clear %fs and %gs. */
+       asm volatile ("xorl %eax, %eax; movl %eax, %fs; movl %eax, %gs");
+
+       /* Clear all 6 debug registers: */
 
 #define CD(register) __asm__("movl %0,%%db" #register ::"r"(0) );