Utilize the drm pagepool code to speed up allocation
performance.
This is similar to the ION pagepool usage, but tries to
utilize generic code instead of a custom implementation.
Cc: Daniel Vetter <daniel@xxxxxxxx>
Cc: Christian Koenig <christian.koenig@xxxxxxx>
Cc: Sumit Semwal <sumit.semwal@xxxxxxxxxx>
Cc: Liam Mark <lmark@xxxxxxxxxxxxxx>
Cc: Chris Goldsworthy <cgoldswo@xxxxxxxxxxxxxx>
Cc: Laura Abbott <labbott@xxxxxxxxxx>
Cc: Brian Starkey <Brian.Starkey@xxxxxxx>
Cc: Hridya Valsaraju <hridya@xxxxxxxxxx>
Cc: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Cc: Sandeep Patil <sspatil@xxxxxxxxxx>
Cc: Daniel Mentz <danielmentz@xxxxxxxxxx>
Cc: Ørjan Eide <orjan.eide@xxxxxxx>
Cc: Robin Murphy <robin.murphy@xxxxxxx>
Cc: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxx>
Cc: Simon Ser <contact@xxxxxxxxxxx>
Cc: James Jones <jajones@xxxxxxxxxx>
Cc: linux-media@xxxxxxxxxxxxxxx
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
---
v2:
* Fix build issue caused by selecting PAGE_POOL w/o NET
as Reported-by: kernel test robot <lkp@xxxxxxxxx>
v3:
* Simplify the page zeroing logic a bit by using kmap_atomic
instead of vmap as suggested by Daniel Mentz
v5:
* Shift away from networking page pool completely to
dmabuf page pool implementation
v6:
* Switch again to using the drm_page_pool code shared w/
ttm_pool
v7:
* Slight rework for drm_page_pool changes
v8:
* Rework to use the rewritten drm_page_pool logic
* Drop explicit buffer zeroing, as the drm_page_pool handles that
---
drivers/dma-buf/heaps/Kconfig | 1 +
drivers/dma-buf/heaps/system_heap.c | 27 ++++++++++++++++++++++++---
2 files changed, 25 insertions(+), 3 deletions(-)
diff --git a/drivers/dma-buf/heaps/Kconfig b/drivers/dma-buf/heaps/Kconfig
index f7aef8bc7119..7e28934e0def 100644
--- a/drivers/dma-buf/heaps/Kconfig
+++ b/drivers/dma-buf/heaps/Kconfig
@@ -4,6 +4,7 @@ config DMABUF_HEAPS_DEFERRED_FREE
config DMABUF_HEAPS_SYSTEM
bool "DMA-BUF System Heap"
depends on DMABUF_HEAPS
+ select DRM_PAGE_POOL
help
Choose this option to enable the system dmabuf heap. The system heap
is backed by pages from the buddy allocator. If in doubt, say Y.
diff --git a/drivers/dma-buf/heaps/system_heap.c b/drivers/dma-buf/heaps/system_heap.c
index 29e49ac17251..006271881d85 100644
--- a/drivers/dma-buf/heaps/system_heap.c
+++ b/drivers/dma-buf/heaps/system_heap.c
@@ -21,6 +21,8 @@
#include <linux/slab.h>
#include <linux/vmalloc.h>
+#include <drm/page_pool.h>
+
static struct dma_heap *sys_heap;
struct system_heap_buffer {
@@ -53,6 +55,7 @@ static gfp_t order_flags[] = {HIGH_ORDER_GFP, LOW_ORDER_GFP, LOW_ORDER_GFP};
*/
static const unsigned int orders[] = {8, 4, 0};
#define NUM_ORDERS ARRAY_SIZE(orders)
+struct drm_page_pool pools[NUM_ORDERS];
static struct sg_table *dup_sg_table(struct sg_table *table)
{
@@ -281,18 +284,28 @@ static void system_heap_vunmap(struct dma_buf *dmabuf, struct dma_buf_map *map)
dma_buf_map_clear(map);
}
+static unsigned long system_heap_free_pages(struct drm_page_pool *pool, struct page *p)
+{
+ __free_pages(p, pool->order);
+ return 1 << pool->order;
+}
+
static void system_heap_dma_buf_release(struct dma_buf *dmabuf)
{
struct system_heap_buffer *buffer = dmabuf->priv;
struct sg_table *table;
struct scatterlist *sg;
- int i;
+ int i, j;
table = &buffer->sg_table;
for_each_sg(table->sgl, sg, table->nents, i) {
struct page *page = sg_page(sg);
- __free_pages(page, compound_order(page));
+ for (j = 0; j < NUM_ORDERS; j++) {
+ if (compound_order(page) == orders[j])
+ break;
+ }
+ drm_page_pool_add(&pools[j], page);
}
sg_free_table(table);
kfree(buffer);
@@ -323,7 +336,9 @@ static struct page *alloc_largest_available(unsigned long size,
if (max_order < orders[i])
continue;
- page = alloc_pages(order_flags[i], orders[i]);
+ page = drm_page_pool_remove(&pools[i]);
+ if (!page)
+ page = alloc_pages(order_flags[i], orders[i]);
if (!page)
continue;
return page;
@@ -423,6 +438,12 @@ static const struct dma_heap_ops system_heap_ops = {
static int system_heap_create(void)
{
struct dma_heap_export_info exp_info;
+ int i;
+
+ for (i = 0; i < NUM_ORDERS; i++) {
+ drm_page_pool_init(&pools[i], orders[i],
+ system_heap_free_pages);
+ }
exp_info.name = "system";
exp_info.ops = &system_heap_ops;
--
2.25.1
