Am 03.12.19 um 14:22 schrieb Thomas Hellström (VMware):
From: Thomas Hellstrom <thellstrom@xxxxxxxxxx>
Using huge page-table entries require that the start of a buffer object
is huge page size aligned. So introduce a ttm_bo_man_get_node_huge()
function that attempts to accomplish this for allocations that are larger
than the huge page size, and provide a new range-manager instance that
uses that function.
I still don't think that this is a good idea.
The driver/userspace should just use a proper alignment if it wants to
use huge pages.
Regards,
Christian.
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Cc: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Ralph Campbell <rcampbell@xxxxxxxxxx>
Cc: "Jérôme Glisse" <jglisse@xxxxxxxxxx>
Cc: "Christian König" <christian.koenig@xxxxxxx>
Signed-off-by: Thomas Hellstrom <thellstrom@xxxxxxxxxx>
---
drivers/gpu/drm/ttm/ttm_bo_manager.c | 92 ++++++++++++++++++++++++++++
include/drm/ttm/ttm_bo_driver.h | 1 +
2 files changed, 93 insertions(+)
diff --git a/drivers/gpu/drm/ttm/ttm_bo_manager.c b/drivers/gpu/drm/ttm/ttm_bo_manager.c
index 18d3debcc949..26aa1a2ae7f1 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_manager.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_manager.c
@@ -89,6 +89,89 @@ static int ttm_bo_man_get_node(struct ttm_mem_type_manager *man,
return 0;
}
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+static int ttm_bo_insert_aligned(struct drm_mm *mm, struct drm_mm_node *node,
+ unsigned long align_pages,
+ const struct ttm_place *place,
+ struct ttm_mem_reg *mem,
+ unsigned long lpfn,
+ enum drm_mm_insert_mode mode)
+{
+ if (align_pages >= mem->page_alignment &&
+ (!mem->page_alignment || align_pages % mem->page_alignment == 0)) {
+ return drm_mm_insert_node_in_range(mm, node,
+ mem->num_pages,
+ align_pages, 0,
+ place->fpfn, lpfn, mode);
+ }
+
+ return -ENOSPC;
+}
+
+static int ttm_bo_man_get_node_huge(struct ttm_mem_type_manager *man,
+ struct ttm_buffer_object *bo,
+ const struct ttm_place *place,
+ struct ttm_mem_reg *mem)
+{
+ struct ttm_range_manager *rman = (struct ttm_range_manager *) man->priv;
+ struct drm_mm *mm = &rman->mm;
+ struct drm_mm_node *node;
+ unsigned long align_pages;
+ unsigned long lpfn;
+ enum drm_mm_insert_mode mode = DRM_MM_INSERT_BEST;
+ int ret;
+
+ node = kzalloc(sizeof(*node), GFP_KERNEL);
+ if (!node)
+ return -ENOMEM;
+
+ lpfn = place->lpfn;
+ if (!lpfn)
+ lpfn = man->size;
+
+ mode = DRM_MM_INSERT_BEST;
+ if (place->flags & TTM_PL_FLAG_TOPDOWN)
+ mode = DRM_MM_INSERT_HIGH;
+
+ spin_lock(&rman->lock);
+ if (IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)) {
+ align_pages = (HPAGE_PUD_SIZE >> PAGE_SHIFT);
+ if (mem->num_pages >= align_pages) {
+ ret = ttm_bo_insert_aligned(mm, node, align_pages,
+ place, mem, lpfn, mode);
+ if (!ret)
+ goto found_unlock;
+ }
+ }
+
+ align_pages = (HPAGE_PMD_SIZE >> PAGE_SHIFT);
+ if (mem->num_pages >= align_pages) {
+ ret = ttm_bo_insert_aligned(mm, node, align_pages, place, mem,
+ lpfn, mode);
+ if (!ret)
+ goto found_unlock;
+ }
+
+ ret = drm_mm_insert_node_in_range(mm, node, mem->num_pages,
+ mem->page_alignment, 0,
+ place->fpfn, lpfn, mode);
+found_unlock:
+ spin_unlock(&rman->lock);
+
+ if (unlikely(ret)) {
+ kfree(node);
+ } else {
+ mem->mm_node = node;
+ mem->start = node->start;
+ }
+
+ return 0;
+}
+#else
+#define ttm_bo_man_get_node_huge ttm_bo_man_get_node
+#endif
+
+
static void ttm_bo_man_put_node(struct ttm_mem_type_manager *man,
struct ttm_mem_reg *mem)
{
@@ -154,3 +237,12 @@ const struct ttm_mem_type_manager_func ttm_bo_manager_func = {
.debug = ttm_bo_man_debug
};
EXPORT_SYMBOL(ttm_bo_manager_func);
+
+const struct ttm_mem_type_manager_func ttm_bo_manager_huge_func = {
+ .init = ttm_bo_man_init,
+ .takedown = ttm_bo_man_takedown,
+ .get_node = ttm_bo_man_get_node_huge,
+ .put_node = ttm_bo_man_put_node,
+ .debug = ttm_bo_man_debug
+};
+EXPORT_SYMBOL(ttm_bo_manager_huge_func);
diff --git a/include/drm/ttm/ttm_bo_driver.h b/include/drm/ttm/ttm_bo_driver.h
index cac7a8a0825a..868bd0d4be6a 100644
--- a/include/drm/ttm/ttm_bo_driver.h
+++ b/include/drm/ttm/ttm_bo_driver.h
@@ -888,5 +888,6 @@ int ttm_bo_pipeline_gutting(struct ttm_buffer_object *bo);
pgprot_t ttm_io_prot(uint32_t caching_flags, pgprot_t tmp);
extern const struct ttm_mem_type_manager_func ttm_bo_manager_func;
+extern const struct ttm_mem_type_manager_func ttm_bo_manager_huge_func;
#endif
