X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fpowerpc%2Fplatforms%2Fcell%2Fspufs%2Fsched.c;fp=arch%2Fpowerpc%2Fplatforms%2Fcell%2Fspufs%2Fsched.c;h=bd6fe4b7a84baab84face56b2d8ca5f5c263db2e;hb=97bf2856c6014879bd04983a3e9dfcdac1e7fe85;hp=963182fbd1aab5cb366f93c5781a24de6ac8940c;hpb=76828883507a47dae78837ab5dec5a5b4513c667;p=linux-2.6.git

diff --git a/arch/powerpc/platforms/cell/spufs/sched.c b/arch/powerpc/platforms/cell/spufs/sched.c
index 963182fbd..bd6fe4b7a 100644
--- a/arch/powerpc/platforms/cell/spufs/sched.c
+++ b/arch/powerpc/platforms/cell/spufs/sched.c
@@ -3,11 +3,7 @@
  * 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
@@ -26,7 +22,6 @@
 
 #undef DEBUG
 
-#include <linux/config.h>
 #include <linux/module.h>
 #include <linux/errno.h>
 #include <linux/sched.h>
@@ -38,139 +33,74 @@
 #include <linux/smp_lock.h>
 #include <linux/stddef.h>
 #include <linux/unistd.h>
+#include <linux/numa.h>
+#include <linux/mutex.h>
+#include <linux/notifier.h>
 
 #include <asm/io.h>
 #include <asm/mmu_context.h>
 #include <asm/spu.h>
 #include <asm/spu_csa.h>
+#include <asm/spu_priv1.h>
 #include "spufs.h"
 
 #define SPU_MIN_TIMESLICE 	(100 * HZ / 1000)
 
 #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 struct spu_prio_array *spu_prio;
 
-static inline struct spu *del_idle(struct spu_runqueue *rq)
+static inline int node_allowed(int node)
 {
-	struct spu *spu;
+	cpumask_t mask;
 
-	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;
+	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 del_active(struct spu_runqueue *rq, struct spu *spu)
+static inline void mm_needs_global_tlbie(struct mm_struct *mm)
 {
-	BUG_ON(rq->nr_active <= 0);
-	BUG_ON(list_empty(&rq->active_list));
-	list_del_init(&spu->sched_list);
-	rq->nr_active--;
-}
+	int nr = (NR_CPUS > 1) ? NR_CPUS : NR_CPUS + 1;
 
-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++;
+	/* Global TLBIE broadcast required with SPEs. */
+	__cpus_setall(&mm->cpu_vm_mask, nr);
 }
 
-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 BLOCKING_NOTIFIER_HEAD(spu_switch_notifier);
 
-static void prio_wakeup(struct spu_runqueue *rq)
+static void spu_switch_notify(struct spu *spu, struct spu_context *ctx)
 {
-	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);
-		}
-	}
+	blocking_notifier_call_chain(&spu_switch_notifier,
+			    ctx ? ctx->object_id : 0, spu);
 }
 
-static void prio_wait(struct spu_runqueue *rq, struct spu_context *ctx,
-		      u64 flags)
+int spu_switch_event_register(struct notifier_block * n)
 {
-	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);
+	return blocking_notifier_chain_register(&spu_switch_notifier, n);
 }
 
-static inline int is_best_prio(struct spu_runqueue *rq)
+int spu_switch_event_unregister(struct notifier_block * n)
 {
-	int best_prio;
-
-	best_prio = sched_find_first_bit(rq->prio.bitmap);
-	return (current->prio < best_prio) ? 1 : 0;
+	return blocking_notifier_chain_unregister(&spu_switch_notifier, n);
 }
 
-static inline void mm_needs_global_tlbie(struct mm_struct *mm)
-{
-	/* 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
-}
 
 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;
 	ctx->spu = spu;
 	ctx->ops = &spu_hw_ops;
 	spu->pid = current->pid;
@@ -180,16 +110,21 @@ static inline void bind_context(struct spu *spu, struct spu_context *ctx)
 	spu->ibox_callback = spufs_ibox_callback;
 	spu->wbox_callback = spufs_wbox_callback;
 	spu->stop_callback = spufs_stop_callback;
+	spu->mfc_callback = spufs_mfc_callback;
+	spu->dma_callback = spufs_dma_callback;
 	mb();
 	spu_unmap_mappings(ctx);
 	spu_restore(&ctx->csa, spu);
 	spu->timestamp = jiffies;
+	spu_cpu_affinity_set(spu, raw_smp_processor_id());
+	spu_switch_notify(spu, ctx);
 }
 
 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_switch_notify(spu, NULL);
 	spu_unmap_mappings(ctx);
 	spu_save(&ctx->csa, spu);
 	spu->timestamp = jiffies;
@@ -197,173 +132,159 @@ static inline void unbind_context(struct spu *spu, struct spu_context *ctx)
 	spu->ibox_callback = NULL;
 	spu->wbox_callback = NULL;
 	spu->stop_callback = NULL;
+	spu->mfc_callback = NULL;
+	spu->dma_callback = NULL;
 	spu->mm = NULL;
 	spu->pid = 0;
 	spu->prio = MAX_PRIO;
 	ctx->ops = &spu_backing_ops;
 	ctx->spu = NULL;
-	ctx->flags = 0;
 	spu->flags = 0;
 	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;
 
-	down(&rq->sem);
-	add_active(rq, spu);
-	up(&rq->sem);
+	mutex_lock(&spu_prio->active_mutex[node]);
+	list_add_tail(&spu->list, &spu_prio->active_list[node]);
+	mutex_unlock(&spu_prio->active_mutex[node]);
 }
 
-/* Lock order:
- *	spu_activate() & spu_deactivate() require the
- *	caller to have down_write(&ctx->state_sema).
+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;
+}
+
+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);
+}
+
+/* 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_irq_setaffinity(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)
@@ -376,8 +297,10 @@ 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)
@@ -385,77 +308,60 @@ 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);
 }