drm/radeon: let sa manager block for fences to wait for v2
Otherwise we can encounter out of memory situations under extreme load.
v2: add documentation for the new function
Signed-off-by: Christian König <deathsimple@vodafone.de>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
index 6715e4c..2cb355b 100644
--- a/drivers/gpu/drm/radeon/radeon.h
+++ b/drivers/gpu/drm/radeon/radeon.h
@@ -362,7 +362,7 @@
* alignment).
*/
struct radeon_sa_manager {
- spinlock_t lock;
+ wait_queue_head_t wq;
struct radeon_bo *bo;
struct list_head *hole;
struct list_head flist[RADEON_NUM_RINGS];
diff --git a/drivers/gpu/drm/radeon/radeon_sa.c b/drivers/gpu/drm/radeon/radeon_sa.c
index 81dbb5b..4e77124 100644
--- a/drivers/gpu/drm/radeon/radeon_sa.c
+++ b/drivers/gpu/drm/radeon/radeon_sa.c
@@ -54,7 +54,7 @@
{
int i, r;
- spin_lock_init(&sa_manager->lock);
+ init_waitqueue_head(&sa_manager->wq);
sa_manager->bo = NULL;
sa_manager->size = size;
sa_manager->domain = domain;
@@ -211,6 +211,39 @@
return false;
}
+/**
+ * radeon_sa_event - Check if we can stop waiting
+ *
+ * @sa_manager: pointer to the sa_manager
+ * @size: number of bytes we want to allocate
+ * @align: alignment we need to match
+ *
+ * Check if either there is a fence we can wait for or
+ * enough free memory to satisfy the allocation directly
+ */
+static bool radeon_sa_event(struct radeon_sa_manager *sa_manager,
+ unsigned size, unsigned align)
+{
+ unsigned soffset, eoffset, wasted;
+ int i;
+
+ for (i = 0; i < RADEON_NUM_RINGS; ++i) {
+ if (!list_empty(&sa_manager->flist[i])) {
+ return true;
+ }
+ }
+
+ soffset = radeon_sa_bo_hole_soffset(sa_manager);
+ eoffset = radeon_sa_bo_hole_eoffset(sa_manager);
+ wasted = (align - (soffset % align)) % align;
+
+ if ((eoffset - soffset) >= (size + wasted)) {
+ return true;
+ }
+
+ return false;
+}
+
static bool radeon_sa_bo_next_hole(struct radeon_sa_manager *sa_manager,
struct radeon_fence **fences,
unsigned *tries)
@@ -297,8 +330,8 @@
INIT_LIST_HEAD(&(*sa_bo)->olist);
INIT_LIST_HEAD(&(*sa_bo)->flist);
- spin_lock(&sa_manager->lock);
- do {
+ spin_lock(&sa_manager->wq.lock);
+ while(1) {
for (i = 0; i < RADEON_NUM_RINGS; ++i) {
fences[i] = NULL;
tries[i] = 0;
@@ -309,30 +342,34 @@
if (radeon_sa_bo_try_alloc(sa_manager, *sa_bo,
size, align)) {
- spin_unlock(&sa_manager->lock);
+ spin_unlock(&sa_manager->wq.lock);
return 0;
}
/* see if we can skip over some allocations */
} while (radeon_sa_bo_next_hole(sa_manager, fences, tries));
- if (block) {
- spin_unlock(&sa_manager->lock);
- r = radeon_fence_wait_any(rdev, fences, false);
- spin_lock(&sa_manager->lock);
- if (r) {
- /* if we have nothing to wait for we
- are practically out of memory */
- if (r == -ENOENT) {
- r = -ENOMEM;
- }
- goto out_err;
- }
+ if (!block) {
+ break;
}
- } while (block);
+
+ spin_unlock(&sa_manager->wq.lock);
+ r = radeon_fence_wait_any(rdev, fences, false);
+ spin_lock(&sa_manager->wq.lock);
+ /* if we have nothing to wait for block */
+ if (r == -ENOENT) {
+ r = wait_event_interruptible_locked(
+ sa_manager->wq,
+ radeon_sa_event(sa_manager, size, align)
+ );
+ }
+ if (r) {
+ goto out_err;
+ }
+ };
out_err:
- spin_unlock(&sa_manager->lock);
+ spin_unlock(&sa_manager->wq.lock);
kfree(*sa_bo);
*sa_bo = NULL;
return r;
@@ -348,7 +385,7 @@
}
sa_manager = (*sa_bo)->manager;
- spin_lock(&sa_manager->lock);
+ spin_lock(&sa_manager->wq.lock);
if (fence && !radeon_fence_signaled(fence)) {
(*sa_bo)->fence = radeon_fence_ref(fence);
list_add_tail(&(*sa_bo)->flist,
@@ -356,7 +393,8 @@
} else {
radeon_sa_bo_remove_locked(*sa_bo);
}
- spin_unlock(&sa_manager->lock);
+ wake_up_all_locked(&sa_manager->wq);
+ spin_unlock(&sa_manager->wq.lock);
*sa_bo = NULL;
}
@@ -366,7 +404,7 @@
{
struct radeon_sa_bo *i;
- spin_lock(&sa_manager->lock);
+ spin_lock(&sa_manager->wq.lock);
list_for_each_entry(i, &sa_manager->olist, olist) {
if (&i->olist == sa_manager->hole) {
seq_printf(m, ">");
@@ -381,6 +419,6 @@
}
seq_printf(m, "\n");
}
- spin_unlock(&sa_manager->lock);
+ spin_unlock(&sa_manager->wq.lock);
}
#endif