* Copyright (C) IBM 2005
* Author: Mark Nutter <mnutter@us.ibm.com>
*
- * SPU scheduler, based on Linux thread priority. For now use
- * a simple "cooperative" yield model with no preemption. SPU
- * scheduling will eventually be preemptive: When a thread with
- * a higher static priority gets ready to run, then an active SPU
- * context will be preempted and returned to the waitq.
+ * 2006-03-31 NUMA domains added.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
#include <linux/smp_lock.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
+#include <linux/numa.h>
+#include <linux/mutex.h>
#include <asm/io.h>
#include <asm/mmu_context.h>
#define SPU_BITMAP_SIZE (((MAX_PRIO+BITS_PER_LONG)/BITS_PER_LONG)+1)
struct spu_prio_array {
- atomic_t nr_blocked;
unsigned long bitmap[SPU_BITMAP_SIZE];
wait_queue_head_t waitq[MAX_PRIO];
+ struct list_head active_list[MAX_NUMNODES];
+ struct mutex active_mutex[MAX_NUMNODES];
};
-/* spu_runqueue - This is the main runqueue data structure for SPUs. */
-struct spu_runqueue {
- struct semaphore sem;
- unsigned long nr_active;
- unsigned long nr_idle;
- unsigned long nr_switches;
- struct list_head active_list;
- struct list_head idle_list;
- struct spu_prio_array prio;
-};
-
-static struct spu_runqueue *spu_runqueues = NULL;
-
-static inline struct spu_runqueue *spu_rq(void)
-{
- /* Future: make this a per-NODE array,
- * and use cpu_to_node(smp_processor_id())
- */
- return spu_runqueues;
-}
-
-static inline struct spu *del_idle(struct spu_runqueue *rq)
-{
- struct spu *spu;
-
- BUG_ON(rq->nr_idle <= 0);
- BUG_ON(list_empty(&rq->idle_list));
- /* Future: Move SPU out of low-power SRI state. */
- spu = list_entry(rq->idle_list.next, struct spu, sched_list);
- list_del_init(&spu->sched_list);
- rq->nr_idle--;
- return spu;
-}
-
-static inline void del_active(struct spu_runqueue *rq, struct spu *spu)
-{
- BUG_ON(rq->nr_active <= 0);
- BUG_ON(list_empty(&rq->active_list));
- list_del_init(&spu->sched_list);
- rq->nr_active--;
-}
-
-static inline void add_idle(struct spu_runqueue *rq, struct spu *spu)
-{
- /* Future: Put SPU into low-power SRI state. */
- list_add_tail(&spu->sched_list, &rq->idle_list);
- rq->nr_idle++;
-}
-
-static inline void add_active(struct spu_runqueue *rq, struct spu *spu)
-{
- rq->nr_active++;
- rq->nr_switches++;
- list_add_tail(&spu->sched_list, &rq->active_list);
-}
-
-static void prio_wakeup(struct spu_runqueue *rq)
-{
- if (atomic_read(&rq->prio.nr_blocked) && rq->nr_idle) {
- int best = sched_find_first_bit(rq->prio.bitmap);
- if (best < MAX_PRIO) {
- wait_queue_head_t *wq = &rq->prio.waitq[best];
- wake_up_interruptible_nr(wq, 1);
- }
- }
-}
-
-static void prio_wait(struct spu_runqueue *rq, struct spu_context *ctx,
- u64 flags)
-{
- int prio = current->prio;
- wait_queue_head_t *wq = &rq->prio.waitq[prio];
- DEFINE_WAIT(wait);
-
- __set_bit(prio, rq->prio.bitmap);
- atomic_inc(&rq->prio.nr_blocked);
- prepare_to_wait_exclusive(wq, &wait, TASK_INTERRUPTIBLE);
- if (!signal_pending(current)) {
- up(&rq->sem);
- up_write(&ctx->state_sema);
- pr_debug("%s: pid=%d prio=%d\n", __FUNCTION__,
- current->pid, current->prio);
- schedule();
- down_write(&ctx->state_sema);
- down(&rq->sem);
- }
- finish_wait(wq, &wait);
- atomic_dec(&rq->prio.nr_blocked);
- if (!waitqueue_active(wq))
- __clear_bit(prio, rq->prio.bitmap);
-}
+static struct spu_prio_array *spu_prio;
-static inline int is_best_prio(struct spu_runqueue *rq)
+static inline int node_allowed(int node)
{
- int best_prio;
+ cpumask_t mask;
- best_prio = sched_find_first_bit(rq->prio.bitmap);
- return (current->prio < best_prio) ? 1 : 0;
+ if (!nr_cpus_node(node))
+ return 0;
+ mask = node_to_cpumask(node);
+ if (!cpus_intersects(mask, current->cpus_allowed))
+ return 0;
+ return 1;
}
static inline void mm_needs_global_tlbie(struct mm_struct *mm)
{
+ int nr = (NR_CPUS > 1) ? NR_CPUS : NR_CPUS + 1;
+
/* Global TLBIE broadcast required with SPEs. */
-#if (NR_CPUS > 1)
- __cpus_setall(&mm->cpu_vm_mask, NR_CPUS);
-#else
- __cpus_setall(&mm->cpu_vm_mask, NR_CPUS+1); /* is this ok? */
-#endif
+ __cpus_setall(&mm->cpu_vm_mask, nr);
}
static inline void bind_context(struct spu *spu, struct spu_context *ctx)
{
- pr_debug("%s: pid=%d SPU=%d\n", __FUNCTION__, current->pid,
- spu->number);
+ pr_debug("%s: pid=%d SPU=%d NODE=%d\n", __FUNCTION__, current->pid,
+ spu->number, spu->node);
spu->ctx = ctx;
spu->flags = 0;
ctx->flags = 0;
spu_unmap_mappings(ctx);
spu_restore(&ctx->csa, spu);
spu->timestamp = jiffies;
+ spu_cpu_affinity_set(spu, raw_smp_processor_id());
}
static inline void unbind_context(struct spu *spu, struct spu_context *ctx)
{
- pr_debug("%s: unbind pid=%d SPU=%d\n", __FUNCTION__,
- spu->pid, spu->number);
+ pr_debug("%s: unbind pid=%d SPU=%d NODE=%d\n", __FUNCTION__,
+ spu->pid, spu->number, spu->node);
spu_unmap_mappings(ctx);
spu_save(&ctx->csa, spu);
spu->timestamp = jiffies;
spu->ctx = NULL;
}
-static void spu_reaper(void *data)
+static inline void spu_add_wq(wait_queue_head_t * wq, wait_queue_t * wait,
+ int prio)
{
- struct spu_context *ctx = data;
- struct spu *spu;
-
- down_write(&ctx->state_sema);
- spu = ctx->spu;
- if (spu && test_bit(SPU_CONTEXT_PREEMPT, &ctx->flags)) {
- if (atomic_read(&spu->rq->prio.nr_blocked)) {
- pr_debug("%s: spu=%d\n", __func__, spu->number);
- ctx->ops->runcntl_stop(ctx);
- spu_deactivate(ctx);
- wake_up_all(&ctx->stop_wq);
- } else {
- clear_bit(SPU_CONTEXT_PREEMPT, &ctx->flags);
- }
- }
- up_write(&ctx->state_sema);
- put_spu_context(ctx);
+ prepare_to_wait_exclusive(wq, wait, TASK_INTERRUPTIBLE);
+ set_bit(prio, spu_prio->bitmap);
}
-static void schedule_spu_reaper(struct spu_runqueue *rq, struct spu *spu)
+static inline void spu_del_wq(wait_queue_head_t * wq, wait_queue_t * wait,
+ int prio)
{
- struct spu_context *ctx = get_spu_context(spu->ctx);
- unsigned long now = jiffies;
- unsigned long expire = spu->timestamp + SPU_MIN_TIMESLICE;
-
- set_bit(SPU_CONTEXT_PREEMPT, &ctx->flags);
- INIT_WORK(&ctx->reap_work, spu_reaper, ctx);
- if (time_after(now, expire))
- schedule_work(&ctx->reap_work);
- else
- schedule_delayed_work(&ctx->reap_work, expire - now);
-}
+ u64 flags;
-static void check_preempt_active(struct spu_runqueue *rq)
-{
- struct list_head *p;
- struct spu *worst = NULL;
-
- list_for_each(p, &rq->active_list) {
- struct spu *spu = list_entry(p, struct spu, sched_list);
- struct spu_context *ctx = spu->ctx;
- if (!test_bit(SPU_CONTEXT_PREEMPT, &ctx->flags)) {
- if (!worst || (spu->prio > worst->prio)) {
- worst = spu;
- }
- }
- }
- if (worst && (current->prio < worst->prio))
- schedule_spu_reaper(rq, worst);
+ __set_current_state(TASK_RUNNING);
+
+ spin_lock_irqsave(&wq->lock, flags);
+
+ remove_wait_queue_locked(wq, wait);
+ if (list_empty(&wq->task_list))
+ clear_bit(prio, spu_prio->bitmap);
+
+ spin_unlock_irqrestore(&wq->lock, flags);
}
-static struct spu *get_idle_spu(struct spu_context *ctx, u64 flags)
+static void spu_prio_wait(struct spu_context *ctx, u64 flags)
{
- struct spu_runqueue *rq;
- struct spu *spu = NULL;
+ int prio = current->prio;
+ wait_queue_head_t *wq = &spu_prio->waitq[prio];
+ DEFINE_WAIT(wait);
- rq = spu_rq();
- down(&rq->sem);
- for (;;) {
- if (rq->nr_idle > 0) {
- if (is_best_prio(rq)) {
- /* Fall through. */
- spu = del_idle(rq);
- break;
- } else {
- prio_wakeup(rq);
- up(&rq->sem);
- yield();
- if (signal_pending(current)) {
- return NULL;
- }
- rq = spu_rq();
- down(&rq->sem);
- continue;
- }
- } else {
- check_preempt_active(rq);
- prio_wait(rq, ctx, flags);
- if (signal_pending(current)) {
- prio_wakeup(rq);
- spu = NULL;
- break;
- }
- continue;
- }
+ if (ctx->spu)
+ return;
+
+ spu_add_wq(wq, &wait, prio);
+
+ if (!signal_pending(current)) {
+ up_write(&ctx->state_sema);
+ pr_debug("%s: pid=%d prio=%d\n", __FUNCTION__,
+ current->pid, current->prio);
+ schedule();
+ down_write(&ctx->state_sema);
}
- up(&rq->sem);
- return spu;
+
+ spu_del_wq(wq, &wait, prio);
}
-static void put_idle_spu(struct spu *spu)
+static void spu_prio_wakeup(void)
{
- struct spu_runqueue *rq = spu->rq;
-
- down(&rq->sem);
- add_idle(rq, spu);
- prio_wakeup(rq);
- up(&rq->sem);
+ int best = sched_find_first_bit(spu_prio->bitmap);
+ if (best < MAX_PRIO) {
+ wait_queue_head_t *wq = &spu_prio->waitq[best];
+ wake_up_interruptible_nr(wq, 1);
+ }
}
static int get_active_spu(struct spu *spu)
{
- struct spu_runqueue *rq = spu->rq;
- struct list_head *p;
+ int node = spu->node;
struct spu *tmp;
int rc = 0;
- down(&rq->sem);
- list_for_each(p, &rq->active_list) {
- tmp = list_entry(p, struct spu, sched_list);
+ mutex_lock(&spu_prio->active_mutex[node]);
+ list_for_each_entry(tmp, &spu_prio->active_list[node], list) {
if (tmp == spu) {
- del_active(rq, spu);
+ list_del_init(&spu->list);
rc = 1;
break;
}
}
- up(&rq->sem);
+ mutex_unlock(&spu_prio->active_mutex[node]);
return rc;
}
static void put_active_spu(struct spu *spu)
{
- struct spu_runqueue *rq = spu->rq;
+ int node = spu->node;
+
+ mutex_lock(&spu_prio->active_mutex[node]);
+ list_add_tail(&spu->list, &spu_prio->active_list[node]);
+ mutex_unlock(&spu_prio->active_mutex[node]);
+}
+
+static struct spu *spu_get_idle(struct spu_context *ctx, u64 flags)
+{
+ struct spu *spu = NULL;
+ int node = cpu_to_node(raw_smp_processor_id());
+ int n;
+
+ for (n = 0; n < MAX_NUMNODES; n++, node++) {
+ node = (node < MAX_NUMNODES) ? node : 0;
+ if (!node_allowed(node))
+ continue;
+ spu = spu_alloc_node(node);
+ if (spu)
+ break;
+ }
+ return spu;
+}
- down(&rq->sem);
- add_active(rq, spu);
- up(&rq->sem);
+static inline struct spu *spu_get(struct spu_context *ctx, u64 flags)
+{
+ /* Future: spu_get_idle() if possible,
+ * otherwise try to preempt an active
+ * context.
+ */
+ return spu_get_idle(ctx, flags);
}
-/* Lock order:
- * spu_activate() & spu_deactivate() require the
- * caller to have down_write(&ctx->state_sema).
+/* The three externally callable interfaces
+ * for the scheduler begin here.
*
- * The rq->sem is breifly held (inside or outside a
- * given ctx lock) for list management, but is never
- * held during save/restore.
+ * spu_activate - bind a context to SPU, waiting as needed.
+ * spu_deactivate - unbind a context from its SPU.
+ * spu_yield - yield an SPU if others are waiting.
*/
int spu_activate(struct spu_context *ctx, u64 flags)
{
struct spu *spu;
+ int ret = 0;
- if (ctx->spu)
- return 0;
- spu = get_idle_spu(ctx, flags);
- if (!spu)
- return (signal_pending(current)) ? -ERESTARTSYS : -EAGAIN;
- bind_context(spu, ctx);
- /*
- * We're likely to wait for interrupts on the same
- * CPU that we are now on, so send them here.
- */
- spu_cpu_affinity_set(spu, raw_smp_processor_id());
- put_active_spu(spu);
- return 0;
+ for (;;) {
+ if (ctx->spu)
+ return 0;
+ spu = spu_get(ctx, flags);
+ if (spu != NULL) {
+ if (ctx->spu != NULL) {
+ spu_free(spu);
+ spu_prio_wakeup();
+ break;
+ }
+ bind_context(spu, ctx);
+ put_active_spu(spu);
+ break;
+ }
+ spu_prio_wait(ctx, flags);
+ if (signal_pending(current)) {
+ ret = -ERESTARTSYS;
+ spu_prio_wakeup();
+ break;
+ }
+ }
+ return ret;
}
void spu_deactivate(struct spu_context *ctx)
return;
needs_idle = get_active_spu(spu);
unbind_context(spu, ctx);
- if (needs_idle)
- put_idle_spu(spu);
+ if (needs_idle) {
+ spu_free(spu);
+ spu_prio_wakeup();
+ }
}
void spu_yield(struct spu_context *ctx)
struct spu *spu;
int need_yield = 0;
- down_write(&ctx->state_sema);
- spu = ctx->spu;
- if (spu && (sched_find_first_bit(spu->rq->prio.bitmap) < MAX_PRIO)) {
- pr_debug("%s: yielding SPU %d\n", __FUNCTION__, spu->number);
- spu_deactivate(ctx);
- ctx->state = SPU_STATE_SAVED;
- need_yield = 1;
- } else if (spu) {
- spu->prio = MAX_PRIO;
+ if (down_write_trylock(&ctx->state_sema)) {
+ if ((spu = ctx->spu) != NULL) {
+ int best = sched_find_first_bit(spu_prio->bitmap);
+ if (best < MAX_PRIO) {
+ pr_debug("%s: yielding SPU %d NODE %d\n",
+ __FUNCTION__, spu->number, spu->node);
+ spu_deactivate(ctx);
+ ctx->state = SPU_STATE_SAVED;
+ need_yield = 1;
+ } else {
+ spu->prio = MAX_PRIO;
+ }
+ }
+ up_write(&ctx->state_sema);
}
- up_write(&ctx->state_sema);
if (unlikely(need_yield))
yield();
}
int __init spu_sched_init(void)
{
- struct spu_runqueue *rq;
- struct spu *spu;
int i;
- rq = spu_runqueues = kmalloc(sizeof(struct spu_runqueue), GFP_KERNEL);
- if (!rq) {
- printk(KERN_WARNING "%s: Unable to allocate runqueues.\n",
+ spu_prio = kzalloc(sizeof(struct spu_prio_array), GFP_KERNEL);
+ if (!spu_prio) {
+ printk(KERN_WARNING "%s: Unable to allocate priority queue.\n",
__FUNCTION__);
return 1;
}
- memset(rq, 0, sizeof(struct spu_runqueue));
- init_MUTEX(&rq->sem);
- INIT_LIST_HEAD(&rq->active_list);
- INIT_LIST_HEAD(&rq->idle_list);
- rq->nr_active = 0;
- rq->nr_idle = 0;
- rq->nr_switches = 0;
- atomic_set(&rq->prio.nr_blocked, 0);
for (i = 0; i < MAX_PRIO; i++) {
- init_waitqueue_head(&rq->prio.waitq[i]);
- __clear_bit(i, rq->prio.bitmap);
+ init_waitqueue_head(&spu_prio->waitq[i]);
+ __clear_bit(i, spu_prio->bitmap);
}
- __set_bit(MAX_PRIO, rq->prio.bitmap);
- for (;;) {
- spu = spu_alloc();
- if (!spu)
- break;
- pr_debug("%s: adding SPU[%d]\n", __FUNCTION__, spu->number);
- add_idle(rq, spu);
- spu->rq = rq;
- spu->timestamp = jiffies;
- }
- if (!rq->nr_idle) {
- printk(KERN_WARNING "%s: No available SPUs.\n", __FUNCTION__);
- kfree(rq);
- return 1;
+ __set_bit(MAX_PRIO, spu_prio->bitmap);
+ for (i = 0; i < MAX_NUMNODES; i++) {
+ mutex_init(&spu_prio->active_mutex[i]);
+ INIT_LIST_HEAD(&spu_prio->active_list[i]);
}
return 0;
}
void __exit spu_sched_exit(void)
{
- struct spu_runqueue *rq = spu_rq();
- struct spu *spu;
-
- if (!rq) {
- printk(KERN_WARNING "%s: no runqueues!\n", __FUNCTION__);
- return;
- }
- while (rq->nr_idle > 0) {
- spu = del_idle(rq);
- if (!spu)
- break;
- spu_free(spu);
+ struct spu *spu, *tmp;
+ int node;
+
+ for (node = 0; node < MAX_NUMNODES; node++) {
+ mutex_lock(&spu_prio->active_mutex[node]);
+ list_for_each_entry_safe(spu, tmp, &spu_prio->active_list[node],
+ list) {
+ list_del_init(&spu->list);
+ spu_free(spu);
+ }
+ mutex_unlock(&spu_prio->active_mutex[node]);
}
- kfree(rq);
+ kfree(spu_prio);
}
projects / linux-2.6-omap-h63xx.git / commitdiff