From 6944561ece14d865238d14e40da858efb29dc2e8 Mon Sep 17 00:00:00 2001 From: Heesub Shin Date: Fri, 30 May 2014 10:26:30 +0900 Subject: [PATCH] staging: ion: optimize struct ion_system_heap struct ion_system_heap has an array for storing pointers to page pools and it is allocated separately from the containing structure. There is no point in allocating those two small objects individually, bothering slab allocator. Using a variable length array simplifies code lines and reduces overhead to the slab. Signed-off-by: Heesub Shin Reviewed-by: Mitchel Humpherys Tested-by: John Stultz Signed-off-by: Greg Kroah-Hartman --- drivers/staging/android/ion/ion_system_heap.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/drivers/staging/android/ion/ion_system_heap.c b/drivers/staging/android/ion/ion_system_heap.c index e0a7e5491f59..c826b4c63861 100644 --- a/drivers/staging/android/ion/ion_system_heap.c +++ b/drivers/staging/android/ion/ion_system_heap.c @@ -49,7 +49,7 @@ static inline unsigned int order_to_size(int order) struct ion_system_heap { struct ion_heap heap; - struct ion_page_pool **pools; + struct ion_page_pool *pools[0]; }; static struct page *alloc_buffer_page(struct ion_system_heap *heap, @@ -264,16 +264,15 @@ struct ion_heap *ion_system_heap_create(struct ion_platform_heap *unused) struct ion_system_heap *heap; int i; - heap = kzalloc(sizeof(struct ion_system_heap), GFP_KERNEL); + heap = kzalloc(sizeof(struct ion_system_heap) + + sizeof(struct ion_page_pool *) * num_orders, + GFP_KERNEL); if (!heap) return ERR_PTR(-ENOMEM); heap->heap.ops = &system_heap_ops; heap->heap.type = ION_HEAP_TYPE_SYSTEM; heap->heap.flags = ION_HEAP_FLAG_DEFER_FREE; - heap->pools = kzalloc(sizeof(struct ion_page_pool *) * num_orders, - GFP_KERNEL); - if (!heap->pools) - goto free_heap; + for (i = 0; i < num_orders; i++) { struct ion_page_pool *pool; gfp_t gfp_flags = low_order_gfp_flags; @@ -292,8 +291,6 @@ struct ion_heap *ion_system_heap_create(struct ion_platform_heap *unused) destroy_pools: while (i--) ion_page_pool_destroy(heap->pools[i]); - kfree(heap->pools); -free_heap: kfree(heap); return ERR_PTR(-ENOMEM); }