drm/i915/gtt: Allow pagedirectory allocations to fail

As we handle the allocation failure of the page directory and tables by
propagating the failure back to userspace, allow it to fail if direct
reclaim is unable to satisfy the request (i.e. disable the oomkiller).
The premise being that if we are unable to allocate a single page for
the pagetable, we will not be able to handle the multitude of pages
required for the gfx operation and we should back off to allow the
system to recover.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=106609Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.william.auld@gmail.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.william.auld@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180522083643.29601-1-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/i915_gem_gtt.c

@@ -42,7 +42,7 @@
 #include "intel_drv.h"
 #include "intel_frontbuffer.h"
 
-#define I915_GFP_DMA (GFP_KERNEL | __GFP_HIGHMEM)
+#define I915_GFP_ALLOW_FAIL (GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN)
 
 /**
  * DOC: Global GTT views
@@ -489,7 +489,7 @@ static int __setup_page_dma(struct i915_address_space *vm,
 			    struct i915_page_dma *p,
 			    gfp_t gfp)
 {
-	p->page = vm_alloc_page(vm, gfp | __GFP_NOWARN | __GFP_NORETRY);
+	p->page = vm_alloc_page(vm, gfp | I915_GFP_ALLOW_FAIL);
 	if (unlikely(!p->page))
 		return -ENOMEM;
 
@@ -506,7 +506,7 @@ static int __setup_page_dma(struct i915_address_space *vm,
 static int setup_page_dma(struct i915_address_space *vm,
 			  struct i915_page_dma *p)
 {
-	return __setup_page_dma(vm, p, I915_GFP_DMA);
+	return __setup_page_dma(vm, p, __GFP_HIGHMEM);
 }
 
 static void cleanup_page_dma(struct i915_address_space *vm,
@@ -614,7 +614,7 @@ static struct i915_page_table *alloc_pt(struct i915_address_space *vm)
 {
 	struct i915_page_table *pt;
 
-	pt = kmalloc(sizeof(*pt), GFP_KERNEL | __GFP_NOWARN);
+	pt = kmalloc(sizeof(*pt), I915_GFP_ALLOW_FAIL);
 	if (unlikely(!pt))
 		return ERR_PTR(-ENOMEM);
 
@@ -651,7 +651,7 @@ static struct i915_page_directory *alloc_pd(struct i915_address_space *vm)
 {
 	struct i915_page_directory *pd;
 
-	pd = kzalloc(sizeof(*pd), GFP_KERNEL | __GFP_NOWARN);
+	pd = kzalloc(sizeof(*pd), I915_GFP_ALLOW_FAIL);
 	if (unlikely(!pd))
 		return ERR_PTR(-ENOMEM);
 
@@ -685,7 +685,7 @@ static int __pdp_init(struct i915_address_space *vm,
 	const unsigned int pdpes = i915_pdpes_per_pdp(vm);
 
 	pdp->page_directory = kmalloc_array(pdpes, sizeof(*pdp->page_directory),
-					    GFP_KERNEL | __GFP_NOWARN);
+					    I915_GFP_ALLOW_FAIL);
 	if (unlikely(!pdp->page_directory))
 		return -ENOMEM;
 
@@ -1229,7 +1229,7 @@ static int gen8_init_scratch(struct i915_address_space *vm)
 {
 	int ret;
 
-	ret = setup_scratch_page(vm, I915_GFP_DMA);
+	ret = setup_scratch_page(vm, __GFP_HIGHMEM);
 	if (ret)
 		return ret;
 
@@ -1974,7 +1974,7 @@ static int gen6_init_scratch(struct i915_address_space *vm)
 {
 	int ret;
 
-	ret = setup_scratch_page(vm, I915_GFP_DMA);
+	ret = setup_scratch_page(vm, __GFP_HIGHMEM);
 	if (ret)
 		return ret;