@@ -1225,18 +1225,6 @@ int __i915_vma_unbind(struct i915_vma *vma)
lockdep_assert_held(&vma->vm->mutex);
- /*
- * First wait upon any activity as retiring the request may
- * have side-effects such as unpinning or even unbinding this vma.
- *
- * XXX Actually waiting under the vm->mutex is a hinderance and
- * should be pipelined wherever possible. In cases where that is
- * unavoidable, we should lift the wait to before the mutex.
- */
- ret = i915_vma_sync(vma);
- if (ret)
- return ret;
-
if (i915_vma_is_pinned(vma)) {
vma_print_allocator(vma, "is pinned");
return -EAGAIN;
@@ -1308,15 +1296,20 @@ int i915_vma_unbind(struct i915_vma *vma)
if (!drm_mm_node_allocated(&vma->node))
return 0;
- if (i915_vma_is_bound(vma, I915_VMA_GLOBAL_BIND))
- /* XXX not always required: nop_clear_range */
- wakeref = intel_runtime_pm_get(&vm->i915->runtime_pm);
-
/* Optimistic wait before taking the mutex */
err = i915_vma_sync(vma);
if (err)
goto out_rpm;
+ if (i915_vma_is_pinned(vma)) {
+ vma_print_allocator(vma, "is pinned");
+ return -EAGAIN;
+ }
+
+ if (i915_vma_is_bound(vma, I915_VMA_GLOBAL_BIND))
+ /* XXX not always required: nop_clear_range */
+ wakeref = intel_runtime_pm_get(&vm->i915->runtime_pm);
+
err = mutex_lock_interruptible_nested(&vma->vm->mutex, !wakeref);
if (err)
goto out_rpm;
Do an early rejection of a i915_vma_unbind() attempt if the i915_vma is currently pinned, without waiting to see if the inflight operations may unpin it. We see this problem with the shrinker trying to unbind the active vma from inside its bind worker: <6> [472.618968] Workqueue: events_unbound fence_work [i915] <4> [472.618970] Call Trace: <4> [472.618974] ? __schedule+0x2e5/0x810 <4> [472.618978] schedule+0x37/0xe0 <4> [472.618982] schedule_preempt_disabled+0xf/0x20 <4> [472.618984] __mutex_lock+0x281/0x9c0 <4> [472.618987] ? mark_held_locks+0x49/0x70 <4> [472.618989] ? _raw_spin_unlock_irqrestore+0x47/0x60 <4> [472.619038] ? i915_vma_unbind+0xae/0x110 [i915] <4> [472.619084] ? i915_vma_unbind+0xae/0x110 [i915] <4> [472.619122] i915_vma_unbind+0xae/0x110 [i915] <4> [472.619165] i915_gem_object_unbind+0x1dc/0x400 [i915] <4> [472.619208] i915_gem_shrink+0x328/0x660 [i915] <4> [472.619250] ? i915_gem_shrink_all+0x38/0x60 [i915] <4> [472.619282] i915_gem_shrink_all+0x38/0x60 [i915] <4> [472.619325] vm_alloc_page.constprop.25+0x1aa/0x240 [i915] <4> [472.619330] ? rcu_read_lock_sched_held+0x4d/0x80 <4> [472.619363] ? __alloc_pd+0xb/0x30 [i915] <4> [472.619366] ? module_assert_mutex_or_preempt+0xf/0x30 <4> [472.619368] ? __module_address+0x23/0xe0 <4> [472.619371] ? is_module_address+0x26/0x40 <4> [472.619374] ? static_obj+0x34/0x50 <4> [472.619376] ? lockdep_init_map+0x4d/0x1e0 <4> [472.619407] setup_page_dma+0xd/0x90 [i915] <4> [472.619437] alloc_pd+0x29/0x50 [i915] <4> [472.619470] __gen8_ppgtt_alloc+0x443/0x6b0 [i915] <4> [472.619503] gen8_ppgtt_alloc+0xd7/0x300 [i915] <4> [472.619535] ppgtt_bind_vma+0x2a/0xe0 [i915] <4> [472.619577] __vma_bind+0x26/0x40 [i915] <4> [472.619611] fence_work+0x1c/0x90 [i915] <4> [472.619617] process_one_work+0x26a/0x620 Fixes: 2850748ef876 ("drm/i915: Pull i915_vma_pin under the vm->mutex") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> --- drivers/gpu/drm/i915/i915_vma.c | 25 +++++++++---------------- 1 file changed, 9 insertions(+), 16 deletions(-)