Commit bd5d6bda authored by Rebecca Schultz Zavin's avatar Rebecca Schultz Zavin Committed by Greg Kroah-Hartman
Browse files

gpu: ion: Modify the system heap to try to allocate large/huge pages 



On some systems there is a performance benefit to reducing tlb pressure
by minimizing the number of chunks in an allocation.

Signed-off-by: default avatarRebecca Schultz Zavin <rebecca@android.com>
[jstultz: modified patch to apply to staging directory]
Signed-off-by: default avatarJohn Stultz <john.stultz@linaro.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 56a7c185

drivers/staging/android/ion/ion_system_heap.c

+90 −26
Original line number Diff line number Diff line
@@ -14,7 +14,10 @@ 
 *

 */



#include <asm/page.h>

#include <linux/dma-mapping.h>

#include <linux/err.h>

#include <linux/highmem.h>

#include <linux/mm.h>

#include <linux/scatterlist.h>

#include <linux/slab.h>
@@ -22,6 +25,35 @@ 
#include "ion.h"

#include "ion_priv.h"



struct page_info {

	struct page *page;

	unsigned long order;

	struct list_head list;

};



static struct page_info *alloc_largest_available(unsigned long size)

{

	static unsigned int orders[] = {8, 4, 0};

	struct page *page;

	struct page_info *info;

	int i;



	for (i = 0; i < ARRAY_SIZE(orders); i++) {

		if (size < (1 << orders[i]) * PAGE_SIZE)

			continue;

		page = alloc_pages(GFP_HIGHUSER | __GFP_ZERO | __GFP_COMP |

				   __GFP_NOWARN | __GFP_NORETRY, orders[i]);

		if (!page)

			continue;

		split_page(page, orders[i]);

		info = kmap(page);

		info->page = page;

		info->order = orders[i];

		return info;

	}

	return NULL;

}



static int ion_system_heap_allocate(struct ion_heap *heap,

				     struct ion_buffer *buffer,

				     unsigned long size, unsigned long align,
@@ -29,30 +61,54 @@ static int ion_system_heap_allocate(struct ion_heap *heap, 
{

	struct sg_table *table;

	struct scatterlist *sg;

	int i, j;

	int npages = PAGE_ALIGN(size) / PAGE_SIZE;

	int ret;

	struct list_head pages;

	struct page_info *info, *tmp_info;

	int i;

	long size_remaining = PAGE_ALIGN(size);



	INIT_LIST_HEAD(&pages);

	while (size_remaining > 0) {

		info = alloc_largest_available(size_remaining);

		if (!info)

			goto err;

		list_add_tail(&info->list, &pages);

		size_remaining -= (1 << info->order) * PAGE_SIZE;

	}



	table = kmalloc(sizeof(struct sg_table), GFP_KERNEL);

	if (!table)

		return -ENOMEM;

	i = sg_alloc_table(table, npages, GFP_KERNEL);

	if (i)

		goto err0;

	for_each_sg(table->sgl, sg, table->nents, i) {

		struct page *page;

		page = alloc_page(GFP_HIGHUSER | __GFP_ZERO);

		if (!page)

		goto err;



	ret = sg_alloc_table(table, PAGE_ALIGN(size) / PAGE_SIZE, GFP_KERNEL);

	if (ret)

		goto err1;

		sg_set_page(sg, page, PAGE_SIZE, 0);



	sg = table->sgl;

	list_for_each_entry_safe(info, tmp_info, &pages, list) {

		struct page *page = info->page;

		for (i = 0; i < (1 << info->order); i++) {

			sg_set_page(sg, page + i, PAGE_SIZE, 0);

			sg = sg_next(sg);

		}

		list_del(&info->list);

		memset(info, 0, sizeof(struct page_info));

		kunmap(page);

	}



	dma_sync_sg_for_device(NULL, table->sgl, table->nents,

			       DMA_BIDIRECTIONAL);



	buffer->priv_virt = table;

	return 0;

err1:

	for_each_sg(table->sgl, sg, i, j)

		__free_page(sg_page(sg));

	sg_free_table(table);

err0:

	kfree(table);

err:

	list_for_each_entry(info, &pages, list) {

		for (i = 0; i < (1 << info->order); i++)

			__free_page(info->page + i);

		kunmap(info->page);

	}

	return -ENOMEM;

}
@@ -63,7 +119,7 @@ void ion_system_heap_free(struct ion_buffer *buffer) 
	struct sg_table *table = buffer->priv_virt;



	for_each_sg(table->sgl, sg, table->nents, i)

		__free_page(sg_page(sg));

		__free_pages(sg_page(sg), get_order(sg_dma_len(sg)));

	if (buffer->sg_table)

		sg_free_table(buffer->sg_table);

	kfree(buffer->sg_table);
@@ -85,22 +141,29 @@ void *ion_system_heap_map_kernel(struct ion_heap *heap, 
				 struct ion_buffer *buffer)

{

	struct scatterlist *sg;

	int i;

	int i, j;

	void *vaddr;

	pgprot_t pgprot;

	struct sg_table *table = buffer->priv_virt;

	struct page **pages = kmalloc(sizeof(struct page *) * table->nents,

	int npages = PAGE_ALIGN(buffer->size) / PAGE_SIZE;

	struct page **pages = kzalloc(sizeof(struct page *) * npages,

				     GFP_KERNEL);



	for_each_sg(table->sgl, sg, table->nents, i)

		pages[i] = sg_page(sg);

	struct page **tmp = pages;



	if (buffer->flags & ION_FLAG_CACHED)

		pgprot = PAGE_KERNEL;

	else

		pgprot = pgprot_writecombine(PAGE_KERNEL);



	vaddr = vmap(pages, table->nents, VM_MAP, pgprot);

	for_each_sg(table->sgl, sg, table->nents, i) {

		int npages_this_entry = PAGE_ALIGN(sg_dma_len(sg)) / PAGE_SIZE;

		struct page *page = sg_page(sg);

		BUG_ON(i >= npages);

		for (j = 0; j < npages_this_entry; j++) {

			*(tmp++) = page++;

		}

	}

	vaddr = vmap(pages, npages, VM_MAP, pgprot);

	kfree(pages);



	return vaddr;
@@ -126,8 +189,9 @@ int ion_system_heap_map_user(struct ion_heap *heap, struct ion_buffer *buffer, 
			offset--;

			continue;

		}

		vm_insert_page(vma, addr, sg_page(sg));

		addr += PAGE_SIZE;

		remap_pfn_range(vma, addr, page_to_pfn(sg_page(sg)),

				sg_dma_len(sg), vma->vm_page_prot);

		addr += sg_dma_len(sg);

	}

	return 0;

}