Reuse/abuse the pagepool code from the network 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: Sumit Semwal <sumit.sem...@linaro.org>
Cc: Liam Mark <lm...@codeaurora.org>
Cc: Chris Goldsworthy <cgold...@codeaurora.org>
Cc: Laura Abbott <labb...@kernel.org>
Cc: Brian Starkey <brian.star...@arm.com>
Cc: Hridya Valsaraju <hri...@google.com>
Cc: Suren Baghdasaryan <sur...@google.com>
Cc: Sandeep Patil <sspa...@google.com>
Cc: Daniel Mentz <danielme...@google.com>
Cc: Ørjan Eide <orjan.e...@arm.com>
Cc: Robin Murphy <robin.mur...@arm.com>
Cc: Ezequiel Garcia <ezequ...@collabora.com>
Cc: Simon Ser <cont...@emersion.fr>
Cc: James Jones <jajo...@nvidia.com>
Cc: linux-me...@vger.kernel.org
Cc: dri-de...@lists.freedesktop.org
Signed-off-by: John Stultz <john.stu...@linaro.org>
---
drivers/dma-buf/heaps/Kconfig | 1 +
drivers/dma-buf/heaps/system_heap.c | 68 +++++++++++++++++++++++++++--
2 files changed, 65 insertions(+), 4 deletions(-)
diff --git a/drivers/dma-buf/heaps/Kconfig b/drivers/dma-buf/heaps/Kconfig
index ecf65204f714..fa5e1c330cce 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 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 17e0e9a68baf..885e30894b77 100644
--- a/drivers/dma-buf/heaps/system_heap.c
+++ b/drivers/dma-buf/heaps/system_heap.c
@@ -20,6 +20,7 @@
#include <linux/scatterlist.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
+#include <net/page_pool.h>
static struct dma_heap *sys_heap;
@@ -53,6 +54,7 @@ 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 page_pool *pools[NUM_ORDERS];
static struct sg_table *dup_sg_table(struct sg_table *table)
{
@@ -281,18 +283,59 @@ static void system_heap_vunmap(struct dma_buf *dmabuf,
struct dma_buf_map *map)
dma_buf_map_clear(map);
}
+static int system_heap_clear_pages(struct page **pages, int num, pgprot_t
pgprot)
+{
+ void *addr = vmap(pages, num, VM_MAP, pgprot);
+
+ if (!addr)
+ return -ENOMEM;
+ memset(addr, 0, PAGE_SIZE * num);
+ vunmap(addr);
+ return 0;
+}
+
+static int system_heap_zero_buffer(struct system_heap_buffer *buffer)
+{
+ struct sg_table *sgt = &buffer->sg_table;
+ struct sg_page_iter piter;
+ struct page *pages[32];
+ int p = 0;
+ int ret = 0;
+
+ for_each_sgtable_page(sgt, &piter, 0) {
+ pages[p++] = sg_page_iter_page(&piter);
+ if (p == ARRAY_SIZE(pages)) {
+ ret = system_heap_clear_pages(pages, p, PAGE_KERNEL);
+ if (ret)
+ return ret;
+ p = 0;
+ }
+ }
+ if (p)
+ ret = system_heap_clear_pages(pages, p, PAGE_KERNEL);
+
+ return ret;
+}
+
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;
+
+ /* Zero the buffer pages before adding back to the pool */
+ system_heap_zero_buffer(buffer);
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;
+ }
+ page_pool_put_full_page(pools[j], page, false);
}
sg_free_table(table);
kfree(buffer);
@@ -322,8 +365,7 @@ static struct page *alloc_largest_available(unsigned long
size,
continue;
if (max_order < orders[i])
continue;
-
- page = alloc_pages(order_flags[i], orders[i]);
+ page = page_pool_alloc_pages(pools[i], order_flags[i]);
if (!page)
continue;
return page;
@@ -428,6 +470,24 @@ 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++) {
+ struct page_pool_params pp;
+
+ memset(&pp, 0, sizeof(pp));
+ pp.order = orders[i];
+ pools[i] = page_pool_create(&pp);
+
+ if (IS_ERR(pools[i])) {
+ int j;
+
+ pr_err("%s: page pool creation failed!\n", __func__);
+ for (j = 0; j < i; j++)
+ page_pool_destroy(pools[j]);
+ return PTR_ERR(pools[i]);
+ }
+ }
exp_info.name = "system";
exp_info.ops = &system_heap_ops;
--
2.17.1
