[PATCH 033/115] gpu: ion: Stop trying to allocate from an order on first failure

John Stultz
2013-12-13T22:27:00Z

From: Rebecca Schultz Zavin <rebecca@android.com>

With this patch the system heap will only try to allocate from each
order as long as allocations succeed. If it failes to obtain a higher
order allocation, it doesn't retry that order.

Signed-off-by: Rebecca Schultz Zavin <rebecca@android.com>
[jstultz: modified patch to apply to staging directory]
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
drivers/staging/android/ion/ion_system_heap.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/android/ion/ion_system_heap.c b/drivers/staging/android/ion/ion_system_heap.c
index ef8afc7..30a225a 100644
--- a/drivers/staging/android/ion/ion_system_heap.c
+++ b/drivers/staging/android/ion/ion_system_heap.c
@@ -32,7 +32,8 @@ struct page_info {
};

static struct page_info *alloc_largest_available(unsigned long size,
- bool split_pages)
+ bool split_pages,
+ unsigned int max_order)
{
static unsigned int orders[] = {8, 4, 0};
struct page *page;
@@ -42,6 +43,8 @@ static struct page_info *alloc_largest_available(unsigned long size,
for (i = 0; i < ARRAY_SIZE(orders); i++) {
if (size < (1 << orders[i]) * PAGE_SIZE)
continue;
+ if (max_order < orders[i])
+ continue;
page = alloc_pages(GFP_HIGHUSER | __GFP_ZERO |
__GFP_NOWARN | __GFP_NORETRY, orders[i]);
if (!page)
@@ -71,13 +74,17 @@ static int ion_system_heap_allocate(struct ion_heap *heap,
bool split_pages = ion_buffer_fault_user_mappings(buffer);

+ unsigned int max_order = orders[0];
+
INIT_LIST_HEAD(&pages);
while (size_remaining > 0) {
- info = alloc_largest_available(size_remaining, split_pages);
+ info = alloc_largest_available(size_remaining, split_pages,
+ max_order);
if (!info)
goto err;
list_add_tail(&info->list, &pages);
size_remaining -= (1 << info->order) * PAGE_SIZE;
+ max_order = info->order;
i++;
}

--
1.8.3.2