summaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c')
-rw-r--r--drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c59
1 files changed, 48 insertions, 11 deletions
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
index da09767fda07..f266b68cf012 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
@@ -730,32 +730,69 @@ static int eb_reserve(struct i915_execbuffer *eb)
bool unpinned;
/*
- * Attempt to pin all of the buffers into the GTT.
- * This is done in 2 phases:
+ * We have one more buffers that we couldn't bind, which could be due to
+ * various reasons. To resolve this we have 4 passes, with every next
+ * level turning the screws tighter:
*
- * 1. Unbind all objects that do not match the GTT constraints for
- * the execbuffer (fenceable, mappable, alignment etc).
- * 2. Bind new objects.
+ * 0. Unbind all objects that do not match the GTT constraints for the
+ * execbuffer (fenceable, mappable, alignment etc). Bind all new
+ * objects. This avoids unnecessary unbinding of later objects in order
+ * to make room for the earlier objects *unless* we need to defragment.
*
- * This avoid unnecessary unbinding of later objects in order to make
- * room for the earlier objects *unless* we need to defragment.
+ * 1. Reorder the buffers, where objects with the most restrictive
+ * placement requirements go first (ignoring fixed location buffers for
+ * now). For example, objects needing the mappable aperture (the first
+ * 256M of GTT), should go first vs objects that can be placed just
+ * about anywhere. Repeat the previous pass.
*
- * Defragmenting is skipped if all objects are pinned at a fixed location.
+ * 2. Consider buffers that are pinned at a fixed location. Also try to
+ * evict the entire VM this time, leaving only objects that we were
+ * unable to lock. Try again to bind the buffers. (still using the new
+ * buffer order).
+ *
+ * 3. We likely have object lock contention for one or more stubborn
+ * objects in the VM, for which we need to evict to make forward
+ * progress (perhaps we are fighting the shrinker?). When evicting the
+ * VM this time around, anything that we can't lock we now track using
+ * the busy_bo, using the full lock (after dropping the vm->mutex to
+ * prevent deadlocks), instead of trylock. We then continue to evict the
+ * VM, this time with the stubborn object locked, which we can now
+ * hopefully unbind (if still bound in the VM). Repeat until the VM is
+ * evicted. Finally we should be able bind everything.
*/
- for (pass = 0; pass <= 2; pass++) {
+ for (pass = 0; pass <= 3; pass++) {
int pin_flags = PIN_USER | PIN_VALIDATE;
if (pass == 0)
pin_flags |= PIN_NONBLOCK;
if (pass >= 1)
- unpinned = eb_unbind(eb, pass == 2);
+ unpinned = eb_unbind(eb, pass >= 2);
if (pass == 2) {
err = mutex_lock_interruptible(&eb->context->vm->mutex);
if (!err) {
- err = i915_gem_evict_vm(eb->context->vm, &eb->ww);
+ err = i915_gem_evict_vm(eb->context->vm, &eb->ww, NULL);
+ mutex_unlock(&eb->context->vm->mutex);
+ }
+ if (err)
+ return err;
+ }
+
+ if (pass == 3) {
+retry:
+ err = mutex_lock_interruptible(&eb->context->vm->mutex);
+ if (!err) {
+ struct drm_i915_gem_object *busy_bo = NULL;
+
+ err = i915_gem_evict_vm(eb->context->vm, &eb->ww, &busy_bo);
mutex_unlock(&eb->context->vm->mutex);
+ if (err && busy_bo) {
+ err = i915_gem_object_lock(busy_bo, &eb->ww);
+ i915_gem_object_put(busy_bo);
+ if (!err)
+ goto retry;
+ }
}
if (err)
return err;