[RFC PATCH] drm/nouveau: rework to new fence interface
From: Maarten Lankhorst
Date: Mon Aug 19 2013 - 06:12:14 EST
nouveau was a bit tricky, it has no support for interrupts on <nv84, so I added
an extra call to nouveau_fence_update in nouveau_fence_emit to increase
the chance slightly that deferred work gets triggered.
This patch depends on the vblank locking fix for the definitions of
nouveau_event_enable_locked and nouveau_event_disable_locked.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxx>
---
diff --git a/drivers/gpu/drm/nouveau/nouveau_fence.c b/drivers/gpu/drm/nouveau/nouveau_fence.c
index be31499..78714e4 100644
--- a/drivers/gpu/drm/nouveau/nouveau_fence.c
+++ b/drivers/gpu/drm/nouveau/nouveau_fence.c
@@ -35,88 +35,115 @@
#include <engine/fifo.h>
-struct fence_work {
- struct work_struct base;
- struct list_head head;
- void (*func)(void *);
- void *data;
-};
+static const struct fence_ops nouveau_fence_ops_uevent;
+static const struct fence_ops nouveau_fence_ops_legacy;
static void
nouveau_fence_signal(struct nouveau_fence *fence)
{
- struct fence_work *work, *temp;
+ __fence_signal(&fence->base);
+ list_del(&fence->head);
- list_for_each_entry_safe(work, temp, &fence->work, head) {
- schedule_work(&work->base);
- list_del(&work->head);
+ if (fence->base.ops == &nouveau_fence_ops_uevent &&
+ fence->event.head.next) {
+ struct nouveau_event *event;
+
+ list_del(&fence->event.head);
+ fence->event.head.next = NULL;
+
+ event = container_of(fence->base.lock, typeof(*event), lock);
+ if (!--event->index[0].refs)
+ event->disable(event, 0);
}
- fence->channel = NULL;
- list_del(&fence->head);
+ fence_put(&fence->base);
}
void
nouveau_fence_context_del(struct nouveau_fence_chan *fctx)
{
struct nouveau_fence *fence, *fnext;
- spin_lock(&fctx->lock);
- list_for_each_entry_safe(fence, fnext, &fctx->pending, head) {
+
+ spin_lock_irq(fctx->lock);
+ list_for_each_entry_safe(fence, fnext, &fctx->pending, head)
nouveau_fence_signal(fence);
- }
- spin_unlock(&fctx->lock);
+ spin_unlock_irq(fctx->lock);
}
void
-nouveau_fence_context_new(struct nouveau_fence_chan *fctx)
+nouveau_fence_context_new(struct nouveau_channel *chan, struct nouveau_fence_chan *fctx)
{
+ struct nouveau_fifo *pfifo = nouveau_fifo(chan->drm->device);
+
+ fctx->lock = &pfifo->uevent->lock;
INIT_LIST_HEAD(&fctx->flip);
INIT_LIST_HEAD(&fctx->pending);
- spin_lock_init(&fctx->lock);
}
+struct nouveau_fence_work {
+ struct work_struct work;
+ struct fence_cb cb;
+ void (*func)(void *);
+ void *data;
+};
+
static void
nouveau_fence_work_handler(struct work_struct *kwork)
{
- struct fence_work *work = container_of(kwork, typeof(*work), base);
+ struct nouveau_fence_work *work = container_of(kwork, typeof(*work), work);
work->func(work->data);
kfree(work);
}
+static void nouveau_fence_work_cb(struct fence *fence, struct fence_cb *cb)
+{
+ struct nouveau_fence_work *work = container_of(cb, typeof(*work), cb);
+
+ schedule_work(&work->work);
+}
+
+/*
+ * In an ideal world, read would not assume the channel context is still alive.
+ * This function may be called from another device, running into free memory as a
+ * result. The drm node should still be there, so we can derive the index from
+ * the fence context.
+ */
+static bool nouveau_fence_is_signaled(struct fence *f)
+{
+ struct nouveau_fence *fence = container_of(f, struct nouveau_fence, base);
+ struct nouveau_channel *chan = fence->channel;
+ struct nouveau_fence_chan *fctx = chan->fence;
+
+ return (int)(fctx->read(chan) - fence->base.seqno) >= 0;
+}
+
void
nouveau_fence_work(struct nouveau_fence *fence,
void (*func)(void *), void *data)
{
- struct nouveau_channel *chan = fence->channel;
- struct nouveau_fence_chan *fctx;
- struct fence_work *work = NULL;
+ struct nouveau_fence_work *work;
- if (nouveau_fence_done(fence)) {
- func(data);
- return;
- }
+ if (fence_is_signaled(&fence->base))
+ goto err;
- fctx = chan->fence;
work = kmalloc(sizeof(*work), GFP_KERNEL);
if (!work) {
WARN_ON(nouveau_fence_wait(fence, false, false));
- func(data);
- return;
- }
-
- spin_lock(&fctx->lock);
- if (!fence->channel) {
- spin_unlock(&fctx->lock);
- kfree(work);
- func(data);
- return;
+ goto err;
}
- INIT_WORK(&work->base, nouveau_fence_work_handler);
+ INIT_WORK(&work->work, nouveau_fence_work_handler);
work->func = func;
work->data = data;
- list_add(&work->head, &fence->work);
- spin_unlock(&fctx->lock);
+
+ if (fence_add_callback(&fence->base, &work->cb, nouveau_fence_work_cb) < 0)
+ goto err_free;
+ return;
+
+err_free:
+ kfree(work);
+err:
+ func(data);
}
static void
@@ -125,33 +152,44 @@ nouveau_fence_update(struct nouveau_channel *chan)
struct nouveau_fence_chan *fctx = chan->fence;
struct nouveau_fence *fence, *fnext;
- spin_lock(&fctx->lock);
+ u32 seq = fctx->read(chan);
+
list_for_each_entry_safe(fence, fnext, &fctx->pending, head) {
- if (fctx->read(chan) < fence->sequence)
+ if ((int)(seq - fence->base.seqno) < 0)
break;
nouveau_fence_signal(fence);
- nouveau_fence_unref(&fence);
}
- spin_unlock(&fctx->lock);
}
int
nouveau_fence_emit(struct nouveau_fence *fence, struct nouveau_channel *chan)
{
struct nouveau_fence_chan *fctx = chan->fence;
+ struct nouveau_fifo *pfifo = nouveau_fifo(chan->drm->device);
+ struct nouveau_fifo_chan *fifo = (void*)chan->object;
+ struct nouveau_fence_priv *priv = (void*)chan->drm->fence;
int ret;
fence->channel = chan;
fence->timeout = jiffies + (15 * DRM_HZ);
- fence->sequence = ++fctx->sequence;
+
+ if (priv->uevent)
+ __fence_init(&fence->base, &nouveau_fence_ops_uevent,
+ &pfifo->uevent->lock,
+ priv->context_base + fifo->chid, ++fctx->sequence);
+ else
+ __fence_init(&fence->base, &nouveau_fence_ops_legacy,
+ &pfifo->uevent->lock,
+ priv->context_base + fifo->chid, ++fctx->sequence);
ret = fctx->emit(fence);
if (!ret) {
- kref_get(&fence->kref);
- spin_lock(&fctx->lock);
+ fence_get(&fence->base);
+ spin_lock_irq(fctx->lock);
+ nouveau_fence_update(chan);
list_add_tail(&fence->head, &fctx->pending);
- spin_unlock(&fctx->lock);
+ spin_unlock_irq(fctx->lock);
}
return ret;
@@ -160,107 +198,71 @@ nouveau_fence_emit(struct nouveau_fence *fence, struct nouveau_channel *chan)
bool
nouveau_fence_done(struct nouveau_fence *fence)
{
- if (fence->channel)
+ if (fence->base.ops == &nouveau_fence_ops_legacy ||
+ fence->base.ops == &nouveau_fence_ops_uevent) {
+ struct nouveau_fence_chan *fctx;
+ unsigned long flags;
+
+ if (test_bit(FENCE_FLAG_SIGNALED_BIT, &fence->base.flags))
+ return true;
+
+ fctx = fence->channel->fence;
+ spin_lock_irqsave(fctx->lock, flags);
nouveau_fence_update(fence->channel);
- return !fence->channel;
+ spin_unlock_irqrestore(fctx->lock, flags);
+ }
+ return fence_is_signaled(&fence->base);
}
-struct nouveau_fence_uevent {
- struct nouveau_eventh handler;
- struct nouveau_fence_priv *priv;
-};
-
-static int
-nouveau_fence_wait_uevent_handler(struct nouveau_eventh *event, int index)
+static long
+nouveau_fence_wait_legacy(struct fence *f, bool intr, long wait)
{
- struct nouveau_fence_uevent *uevent =
- container_of(event, struct nouveau_fence_uevent, handler);
- wake_up_all(&uevent->priv->waiting);
- return NVKM_EVENT_KEEP;
-}
+ struct nouveau_fence *fence = container_of(f, typeof(*fence), base);
+ unsigned long sleep_time = NSEC_PER_MSEC / 1000;
+ unsigned long t = jiffies, timeout = t + wait;
-static int
-nouveau_fence_wait_uevent(struct nouveau_fence *fence, bool intr)
+ while (!nouveau_fence_done(fence)) {
+ ktime_t kt;
-{
- struct nouveau_channel *chan = fence->channel;
- struct nouveau_fifo *pfifo = nouveau_fifo(chan->drm->device);
- struct nouveau_fence_priv *priv = chan->drm->fence;
- struct nouveau_fence_uevent uevent = {
- .handler.func = nouveau_fence_wait_uevent_handler,
- .priv = priv,
- };
- int ret = 0;
+ t = jiffies;
- nouveau_event_get(pfifo->uevent, 0, &uevent.handler);
-
- if (fence->timeout) {
- unsigned long timeout = fence->timeout - jiffies;
-
- if (time_before(jiffies, fence->timeout)) {
- if (intr) {
- ret = wait_event_interruptible_timeout(
- priv->waiting,
- nouveau_fence_done(fence),
- timeout);
- } else {
- ret = wait_event_timeout(priv->waiting,
- nouveau_fence_done(fence),
- timeout);
- }
+ if (wait != MAX_SCHEDULE_TIMEOUT && time_after_eq(t, timeout)) {
+ __set_current_state(TASK_RUNNING);
+ return 0;
}
- if (ret >= 0) {
- fence->timeout = jiffies + ret;
- if (time_after_eq(jiffies, fence->timeout))
- ret = -EBUSY;
- }
- } else {
- if (intr) {
- ret = wait_event_interruptible(priv->waiting,
- nouveau_fence_done(fence));
- } else {
- wait_event(priv->waiting, nouveau_fence_done(fence));
- }
+ __set_current_state(intr ? TASK_INTERRUPTIBLE :
+ TASK_UNINTERRUPTIBLE);
+
+ kt = ktime_set(0, sleep_time);
+ schedule_hrtimeout(&kt, HRTIMER_MODE_REL);
+ sleep_time *= 2;
+ if (sleep_time > NSEC_PER_MSEC)
+ sleep_time = NSEC_PER_MSEC;
+
+ if (intr && signal_pending(current))
+ return -ERESTARTSYS;
}
- nouveau_event_put(pfifo->uevent, 0, &uevent.handler);
- if (unlikely(ret < 0))
- return ret;
+ __set_current_state(TASK_RUNNING);
- return 0;
+ return timeout - t;
}
-int
-nouveau_fence_wait(struct nouveau_fence *fence, bool lazy, bool intr)
+static int
+nouveau_fence_wait_busy(struct nouveau_fence *fence, bool intr)
{
- struct nouveau_channel *chan = fence->channel;
- struct nouveau_fence_priv *priv = chan ? chan->drm->fence : NULL;
- unsigned long sleep_time = NSEC_PER_MSEC / 1000;
- ktime_t t;
int ret = 0;
- while (priv && priv->uevent && lazy && !nouveau_fence_done(fence)) {
- ret = nouveau_fence_wait_uevent(fence, intr);
- if (ret < 0)
- return ret;
- }
-
while (!nouveau_fence_done(fence)) {
- if (fence->timeout && time_after_eq(jiffies, fence->timeout)) {
+ if (time_after_eq(jiffies, fence->timeout)) {
ret = -EBUSY;
break;
}
- __set_current_state(intr ? TASK_INTERRUPTIBLE :
- TASK_UNINTERRUPTIBLE);
- if (lazy) {
- t = ktime_set(0, sleep_time);
- schedule_hrtimeout(&t, HRTIMER_MODE_REL);
- sleep_time *= 2;
- if (sleep_time > NSEC_PER_MSEC)
- sleep_time = NSEC_PER_MSEC;
- }
+ __set_current_state(intr ?
+ TASK_INTERRUPTIBLE :
+ TASK_UNINTERRUPTIBLE);
if (intr && signal_pending(current)) {
ret = -ERESTARTSYS;
@@ -273,14 +275,31 @@ nouveau_fence_wait(struct nouveau_fence *fence, bool lazy, bool intr)
}
int
+nouveau_fence_wait(struct nouveau_fence *fence, bool lazy, bool intr)
+{
+ long ret;
+
+ if (!lazy)
+ return nouveau_fence_wait_busy(fence, intr);
+
+ ret = fence_wait_timeout(&fence->base, intr, 15 * DRM_HZ);
+ if (ret < 0)
+ return ret;
+ else if (!ret)
+ return -EBUSY;
+ else
+ return 0;
+}
+
+int
nouveau_fence_sync(struct nouveau_fence *fence, struct nouveau_channel *chan)
{
struct nouveau_fence_chan *fctx = chan->fence;
- struct nouveau_channel *prev;
int ret = 0;
- prev = fence ? fence->channel : NULL;
- if (prev) {
+ if (fence) {
+ struct nouveau_channel *prev = fence->channel;
+
if (unlikely(prev != chan && !nouveau_fence_done(fence))) {
ret = fctx->sync(fence, prev, chan);
if (unlikely(ret))
@@ -291,25 +310,18 @@ nouveau_fence_sync(struct nouveau_fence *fence, struct nouveau_channel *chan)
return ret;
}
-static void
-nouveau_fence_del(struct kref *kref)
-{
- struct nouveau_fence *fence = container_of(kref, typeof(*fence), kref);
- kfree(fence);
-}
-
void
nouveau_fence_unref(struct nouveau_fence **pfence)
{
if (*pfence)
- kref_put(&(*pfence)->kref, nouveau_fence_del);
+ fence_put(&(*pfence)->base);
*pfence = NULL;
}
struct nouveau_fence *
nouveau_fence_ref(struct nouveau_fence *fence)
{
- kref_get(&fence->kref);
+ fence_get(&fence->base);
return fence;
}
@@ -327,9 +339,7 @@ nouveau_fence_new(struct nouveau_channel *chan, bool sysmem,
if (!fence)
return -ENOMEM;
- INIT_LIST_HEAD(&fence->work);
fence->sysmem = sysmem;
- kref_init(&fence->kref);
ret = nouveau_fence_emit(fence, chan);
if (ret)
@@ -338,3 +348,64 @@ nouveau_fence_new(struct nouveau_channel *chan, bool sysmem,
*pfence = fence;
return ret;
}
+
+
+static bool nouveau_fence_no_signaling(struct fence *f)
+{
+ /*
+ * This needs uevents to work correctly, but fence_add_callback relies on
+ * being able to enable signaling. It will still get signaled eventually,
+ * just not right away.
+ */
+ if (nouveau_fence_is_signaled(f))
+ return false;
+
+ return true;
+}
+
+static const struct fence_ops nouveau_fence_ops_legacy = {
+ .enable_signaling = nouveau_fence_no_signaling,
+ .signaled = nouveau_fence_is_signaled,
+ .wait = nouveau_fence_wait_legacy,
+ .release = NULL
+};
+
+static int
+nouveau_fence_wait_uevent_handler(struct nouveau_eventh *event, int index)
+{
+ struct nouveau_fence *fence =
+ container_of(event, struct nouveau_fence, event);
+
+ if (nouveau_fence_is_signaled(&fence->base))
+ nouveau_fence_signal(fence);
+
+ /*
+ * NVKM_EVENT_DROP is never appropriate here, nouveau_fence_signal
+ * will unlink and free the event if needed.
+ */
+ return NVKM_EVENT_KEEP;
+}
+
+static bool nouveau_fence_enable_signaling(struct fence *f)
+{
+ struct nouveau_fence *fence = container_of(f, struct nouveau_fence, base);
+ struct nouveau_event *event = container_of(f->lock, struct nouveau_event, lock);
+
+ nouveau_event_enable_locked(event, 0);
+ if (nouveau_fence_is_signaled(f)) {
+ nouveau_event_disable_locked(event, 0, 1);
+ return false;
+ }
+
+ list_add_tail(&fence->event.head, &event->index[0].list);
+ fence->event.func = nouveau_fence_wait_uevent_handler;
+
+ return true;
+}
+
+static const struct fence_ops nouveau_fence_ops_uevent = {
+ .enable_signaling = nouveau_fence_enable_signaling,
+ .signaled = nouveau_fence_is_signaled,
+ .wait = fence_default_wait,
+ .release = NULL
+};
diff --git a/drivers/gpu/drm/nouveau/nouveau_fence.h b/drivers/gpu/drm/nouveau/nouveau_fence.h
index c57bb61..1df933c 100644
--- a/drivers/gpu/drm/nouveau/nouveau_fence.h
+++ b/drivers/gpu/drm/nouveau/nouveau_fence.h
@@ -1,18 +1,20 @@
#ifndef __NOUVEAU_FENCE_H__
#define __NOUVEAU_FENCE_H__
+#include <linux/fence.h>
+
struct nouveau_drm;
struct nouveau_fence {
+ struct fence base;
+
struct list_head head;
- struct list_head work;
- struct kref kref;
+ struct nouveau_eventh event;
bool sysmem;
struct nouveau_channel *channel;
unsigned long timeout;
- u32 sequence;
};
int nouveau_fence_new(struct nouveau_channel *, bool sysmem,
@@ -38,8 +40,9 @@ struct nouveau_fence_chan {
int (*emit32)(struct nouveau_channel *, u64, u32);
int (*sync32)(struct nouveau_channel *, u64, u32);
- spinlock_t lock;
+ spinlock_t *lock;
u32 sequence;
+ u32 context;
};
struct nouveau_fence_priv {
@@ -49,13 +52,14 @@ struct nouveau_fence_priv {
int (*context_new)(struct nouveau_channel *);
void (*context_del)(struct nouveau_channel *);
- wait_queue_head_t waiting;
bool uevent;
+
+ u32 contexts, context_base;
};
#define nouveau_fence(drm) ((struct nouveau_fence_priv *)(drm)->fence)
-void nouveau_fence_context_new(struct nouveau_fence_chan *);
+void nouveau_fence_context_new(struct nouveau_channel *, struct nouveau_fence_chan *);
void nouveau_fence_context_del(struct nouveau_fence_chan *);
int nv04_fence_create(struct nouveau_drm *);
diff --git a/drivers/gpu/drm/nouveau/nv04_fence.c b/drivers/gpu/drm/nouveau/nv04_fence.c
index 94eadd1..997c541 100644
--- a/drivers/gpu/drm/nouveau/nv04_fence.c
+++ b/drivers/gpu/drm/nouveau/nv04_fence.c
@@ -43,7 +43,7 @@ nv04_fence_emit(struct nouveau_fence *fence)
int ret = RING_SPACE(chan, 2);
if (ret == 0) {
BEGIN_NV04(chan, NvSubSw, 0x0150, 1);
- OUT_RING (chan, fence->sequence);
+ OUT_RING (chan, fence->base.seqno);
FIRE_RING (chan);
}
return ret;
@@ -77,7 +77,7 @@ nv04_fence_context_new(struct nouveau_channel *chan)
{
struct nv04_fence_chan *fctx = kzalloc(sizeof(*fctx), GFP_KERNEL);
if (fctx) {
- nouveau_fence_context_new(&fctx->base);
+ nouveau_fence_context_new(chan, &fctx->base);
fctx->base.emit = nv04_fence_emit;
fctx->base.sync = nv04_fence_sync;
fctx->base.read = nv04_fence_read;
diff --git a/drivers/gpu/drm/nouveau/nv10_fence.c b/drivers/gpu/drm/nouveau/nv10_fence.c
index 06f434f..e8f73f7 100644
--- a/drivers/gpu/drm/nouveau/nv10_fence.c
+++ b/drivers/gpu/drm/nouveau/nv10_fence.c
@@ -36,7 +36,7 @@ nv10_fence_emit(struct nouveau_fence *fence)
int ret = RING_SPACE(chan, 2);
if (ret == 0) {
BEGIN_NV04(chan, 0, NV10_SUBCHAN_REF_CNT, 1);
- OUT_RING (chan, fence->sequence);
+ OUT_RING (chan, fence->base.seqno);
FIRE_RING (chan);
}
return ret;
@@ -74,7 +74,7 @@ nv10_fence_context_new(struct nouveau_channel *chan)
if (!fctx)
return -ENOMEM;
- nouveau_fence_context_new(&fctx->base);
+ nouveau_fence_context_new(chan, &fctx->base);
fctx->base.emit = nv10_fence_emit;
fctx->base.read = nv10_fence_read;
fctx->base.sync = nv10_fence_sync;
diff --git a/drivers/gpu/drm/nouveau/nv17_fence.c b/drivers/gpu/drm/nouveau/nv17_fence.c
index 22aa996..e404bab 100644
--- a/drivers/gpu/drm/nouveau/nv17_fence.c
+++ b/drivers/gpu/drm/nouveau/nv17_fence.c
@@ -83,7 +83,7 @@ nv17_fence_context_new(struct nouveau_channel *chan)
if (!fctx)
return -ENOMEM;
- nouveau_fence_context_new(&fctx->base);
+ nouveau_fence_context_new(chan, &fctx->base);
fctx->base.emit = nv10_fence_emit;
fctx->base.read = nv10_fence_read;
fctx->base.sync = nv17_fence_sync;
diff --git a/drivers/gpu/drm/nouveau/nv50_fence.c b/drivers/gpu/drm/nouveau/nv50_fence.c
index 0ee3638..19f6fcc 100644
--- a/drivers/gpu/drm/nouveau/nv50_fence.c
+++ b/drivers/gpu/drm/nouveau/nv50_fence.c
@@ -47,7 +47,7 @@ nv50_fence_context_new(struct nouveau_channel *chan)
if (!fctx)
return -ENOMEM;
- nouveau_fence_context_new(&fctx->base);
+ nouveau_fence_context_new(chan, &fctx->base);
fctx->base.emit = nv10_fence_emit;
fctx->base.read = nv10_fence_read;
fctx->base.sync = nv17_fence_sync;
diff --git a/drivers/gpu/drm/nouveau/nv84_fence.c b/drivers/gpu/drm/nouveau/nv84_fence.c
index 9fd475c..8a06727 100644
--- a/drivers/gpu/drm/nouveau/nv84_fence.c
+++ b/drivers/gpu/drm/nouveau/nv84_fence.c
@@ -89,7 +89,7 @@ nv84_fence_emit(struct nouveau_fence *fence)
else
addr += fctx->vma.offset;
- return fctx->base.emit32(chan, addr, fence->sequence);
+ return fctx->base.emit32(chan, addr, fence->base.seqno);
}
static int
@@ -105,7 +105,7 @@ nv84_fence_sync(struct nouveau_fence *fence,
else
addr += fctx->vma.offset;
- return fctx->base.sync32(chan, addr, fence->sequence);
+ return fctx->base.sync32(chan, addr, fence->base.seqno);
}
static u32
@@ -149,12 +149,14 @@ nv84_fence_context_new(struct nouveau_channel *chan)
if (!fctx)
return -ENOMEM;
- nouveau_fence_context_new(&fctx->base);
+ nouveau_fence_context_new(chan, &fctx->base);
fctx->base.emit = nv84_fence_emit;
fctx->base.sync = nv84_fence_sync;
fctx->base.read = nv84_fence_read;
fctx->base.emit32 = nv84_fence_emit32;
fctx->base.sync32 = nv84_fence_sync32;
+ fctx->base.sequence = nv84_fence_read(chan);
+ fctx->base.context = priv->base.context_base + fifo->chid;
ret = nouveau_bo_vma_add(priv->bo, client->vm, &fctx->vma);
if (ret == 0) {
@@ -239,7 +241,8 @@ nv84_fence_create(struct nouveau_drm *drm)
priv->base.context_new = nv84_fence_context_new;
priv->base.context_del = nv84_fence_context_del;
- init_waitqueue_head(&priv->base.waiting);
+ priv->base.contexts = pfifo->max + 1;
+ priv->base.context_base = fence_context_alloc(priv->base.contexts);
priv->base.uevent = true;
ret = nouveau_bo_new(drm->dev, 16 * (pfifo->max + 1), 0,
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