diff options
author | Francisco Jerez <currojerez@riseup.net> | 2010-10-11 03:37:32 +0200 |
---|---|---|
committer | Ben Skeggs <bskeggs@redhat.com> | 2010-11-18 14:38:22 +1000 |
commit | 7bb94d26ad62ca1d6b5e11db6e26425785cc46ac (patch) | |
tree | 7e05690c2fb37172ff1cfd82c130320daf13aa0e /drivers/gpu | |
parent | cbab95db84f2a444d99bec77bac8b9b6ef20d11c (diff) |
drm/nouveau: Avoid lock dependency between ramht and ramin spinlocks.
The ramht code called some gpuobj functions with the HARDIRQ-safe
RAMHT spinlock held, this could potentially lead to a dead lock
because ramin_lock is HARDIRQ-unsafe.
Signed-off-by: Francisco Jerez <currojerez@riseup.net>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Diffstat (limited to 'drivers/gpu')
-rw-r--r-- | drivers/gpu/drm/nouveau/nouveau_ramht.c | 71 |
1 files changed, 44 insertions, 27 deletions
diff --git a/drivers/gpu/drm/nouveau/nouveau_ramht.c b/drivers/gpu/drm/nouveau/nouveau_ramht.c index 7f16697cc96c..2d8580927ca4 100644 --- a/drivers/gpu/drm/nouveau/nouveau_ramht.c +++ b/drivers/gpu/drm/nouveau/nouveau_ramht.c @@ -153,26 +153,42 @@ nouveau_ramht_insert(struct nouveau_channel *chan, u32 handle, return -ENOMEM; } +static struct nouveau_ramht_entry * +nouveau_ramht_remove_entry(struct nouveau_channel *chan, u32 handle) +{ + struct nouveau_ramht *ramht = chan ? chan->ramht : NULL; + struct nouveau_ramht_entry *entry; + unsigned long flags; + + if (!ramht) + return NULL; + + spin_lock_irqsave(&ramht->lock, flags); + list_for_each_entry(entry, &ramht->entries, head) { + if (entry->channel == chan && + (!handle || entry->handle == handle)) { + list_del(&entry->head); + spin_unlock_irqrestore(&ramht->lock, flags); + + return entry; + } + } + spin_unlock_irqrestore(&ramht->lock, flags); + + return NULL; +} + static void -nouveau_ramht_remove_locked(struct nouveau_channel *chan, u32 handle) +nouveau_ramht_remove_hash(struct nouveau_channel *chan, u32 handle) { struct drm_device *dev = chan->dev; struct drm_nouveau_private *dev_priv = dev->dev_private; struct nouveau_instmem_engine *instmem = &dev_priv->engine.instmem; struct nouveau_gpuobj *ramht = chan->ramht->gpuobj; - struct nouveau_ramht_entry *entry, *tmp; + unsigned long flags; u32 co, ho; - list_for_each_entry_safe(entry, tmp, &chan->ramht->entries, head) { - if (entry->channel != chan || entry->handle != handle) - continue; - - nouveau_gpuobj_ref(NULL, &entry->gpuobj); - list_del(&entry->head); - kfree(entry); - break; - } - + spin_lock_irqsave(&chan->ramht->lock, flags); co = ho = nouveau_ramht_hash_handle(chan, handle); do { if (nouveau_ramht_entry_valid(dev, ramht, co) && @@ -184,7 +200,7 @@ nouveau_ramht_remove_locked(struct nouveau_channel *chan, u32 handle) nv_wo32(ramht, co + 0, 0x00000000); nv_wo32(ramht, co + 4, 0x00000000); instmem->flush(dev); - return; + goto out; } co += 8; @@ -194,17 +210,22 @@ nouveau_ramht_remove_locked(struct nouveau_channel *chan, u32 handle) NV_ERROR(dev, "RAMHT entry not found. ch=%d, handle=0x%08x\n", chan->id, handle); +out: + spin_unlock_irqrestore(&chan->ramht->lock, flags); } void nouveau_ramht_remove(struct nouveau_channel *chan, u32 handle) { - struct nouveau_ramht *ramht = chan->ramht; - unsigned long flags; + struct nouveau_ramht_entry *entry; - spin_lock_irqsave(&ramht->lock, flags); - nouveau_ramht_remove_locked(chan, handle); - spin_unlock_irqrestore(&ramht->lock, flags); + entry = nouveau_ramht_remove_entry(chan, handle); + if (!entry) + return; + + nouveau_ramht_remove_hash(chan, entry->handle); + nouveau_gpuobj_ref(NULL, &entry->gpuobj); + kfree(entry); } struct nouveau_gpuobj * @@ -265,23 +286,19 @@ void nouveau_ramht_ref(struct nouveau_ramht *ref, struct nouveau_ramht **ptr, struct nouveau_channel *chan) { - struct nouveau_ramht_entry *entry, *tmp; + struct nouveau_ramht_entry *entry; struct nouveau_ramht *ramht; - unsigned long flags; if (ref) kref_get(&ref->refcount); ramht = *ptr; if (ramht) { - spin_lock_irqsave(&ramht->lock, flags); - list_for_each_entry_safe(entry, tmp, &ramht->entries, head) { - if (entry->channel != chan) - continue; - - nouveau_ramht_remove_locked(chan, entry->handle); + while ((entry = nouveau_ramht_remove_entry(chan, 0))) { + nouveau_ramht_remove_hash(chan, entry->handle); + nouveau_gpuobj_ref(NULL, &entry->gpuobj); + kfree(entry); } - spin_unlock_irqrestore(&ramht->lock, flags); kref_put(&ramht->refcount, nouveau_ramht_del); } |