Re: [PATCH 2/2] staging: android: ion: Combine cache and uncache pools

From: Yisheng Xie
Date: Wed Feb 07 2018 - 19:53:30 EST


Hi Sumit,

On 2018/2/7 22:34, Sumit Semwal wrote:
> Hello Yisheng,
>
> On 7 February 2018 at 09:29, Yisheng Xie <xieyisheng1@xxxxxxxxxx> wrote:
>> Now we call dma_map in the dma_buf API callbacks and handle explicit
>> caching by the dma_buf sync API, which make cache and uncache pools
>> in the same handling flow, which can be combined.
>>
> Thanks for the patch! Perhaps you should also put the version history
> here, to capture the changes from previous versions?

hmm, this is first version of this patch. Except for the resent ones, all
of the patches I have sent about ion is v1 with different cleanup. Maybe
I can send them into one patchset in v2 after merge window. Sorry for not
having put them together.

Thanks
Yisheng
>
>> Signed-off-by: Yisheng Xie <xieyisheng1@xxxxxxxxxx>
> With that done, please feel free to add
> Acked-by: Sumit Semwal <sumit.semwal@xxxxxxxxxx>
>
>> ---
>> drivers/staging/android/ion/ion.c | 5 --
>> drivers/staging/android/ion/ion.h | 13 +----
>> drivers/staging/android/ion/ion_page_pool.c | 5 +-
>> drivers/staging/android/ion/ion_system_heap.c | 76 +++++----------------------
>> 4 files changed, 16 insertions(+), 83 deletions(-)
>>
>> diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c
>> index 461b193..c094be2 100644
>> --- a/drivers/staging/android/ion/ion.c
>> +++ b/drivers/staging/android/ion/ion.c
>> @@ -33,11 +33,6 @@
>> static struct ion_device *internal_dev;
>> static int heap_id;
>>
>> -bool ion_buffer_cached(struct ion_buffer *buffer)
>> -{
>> - return !!(buffer->flags & ION_FLAG_CACHED);
>> -}
>> -
>> /* this function should only be called while dev->lock is held */
>> static void ion_buffer_add(struct ion_device *dev,
>> struct ion_buffer *buffer)
>> diff --git a/drivers/staging/android/ion/ion.h b/drivers/staging/android/ion/ion.h
>> index 1bc443f..ea08978 100644
>> --- a/drivers/staging/android/ion/ion.h
>> +++ b/drivers/staging/android/ion/ion.h
>> @@ -185,14 +185,6 @@ struct ion_heap {
>> };
>>
>> /**
>> - * ion_buffer_cached - this ion buffer is cached
>> - * @buffer: buffer
>> - *
>> - * indicates whether this ion buffer is cached
>> - */
>> -bool ion_buffer_cached(struct ion_buffer *buffer);
>> -
>> -/**
>> * ion_device_add_heap - adds a heap to the ion device
>> * @heap: the heap to add
>> */
>> @@ -302,7 +294,6 @@ size_t ion_heap_freelist_shrink(struct ion_heap *heap,
>> * @gfp_mask: gfp_mask to use from alloc
>> * @order: order of pages in the pool
>> * @list: plist node for list of pools
>> - * @cached: it's cached pool or not
>> *
>> * Allows you to keep a pool of pre allocated pages to use from your heap.
>> * Keeping a pool of pages that is ready for dma, ie any cached mapping have
>> @@ -312,7 +303,6 @@ size_t ion_heap_freelist_shrink(struct ion_heap *heap,
>> struct ion_page_pool {
>> int high_count;
>> int low_count;
>> - bool cached;
>> struct list_head high_items;
>> struct list_head low_items;
>> struct mutex mutex;
>> @@ -321,8 +311,7 @@ struct ion_page_pool {
>> struct plist_node list;
>> };
>>
>> -struct ion_page_pool *ion_page_pool_create(gfp_t gfp_mask, unsigned int order,
>> - bool cached);
>> +struct ion_page_pool *ion_page_pool_create(gfp_t gfp_mask, unsigned int order);
>> void ion_page_pool_destroy(struct ion_page_pool *pool);
>> struct page *ion_page_pool_alloc(struct ion_page_pool *pool);
>> void ion_page_pool_free(struct ion_page_pool *pool, struct page *page);
>> diff --git a/drivers/staging/android/ion/ion_page_pool.c b/drivers/staging/android/ion/ion_page_pool.c
>> index 6d2caf0..db8f614 100644
>> --- a/drivers/staging/android/ion/ion_page_pool.c
>> +++ b/drivers/staging/android/ion/ion_page_pool.c
>> @@ -123,8 +123,7 @@ int ion_page_pool_shrink(struct ion_page_pool *pool, gfp_t gfp_mask,
>> return freed;
>> }
>>
>> -struct ion_page_pool *ion_page_pool_create(gfp_t gfp_mask, unsigned int order,
>> - bool cached)
>> +struct ion_page_pool *ion_page_pool_create(gfp_t gfp_mask, unsigned int order)
>> {
>> struct ion_page_pool *pool = kmalloc(sizeof(*pool), GFP_KERNEL);
>>
>> @@ -138,8 +137,6 @@ struct ion_page_pool *ion_page_pool_create(gfp_t gfp_mask, unsigned int order,
>> pool->order = order;
>> mutex_init(&pool->mutex);
>> plist_node_init(&pool->list, order);
>> - if (cached)
>> - pool->cached = true;
>>
>> return pool;
>> }
>> diff --git a/drivers/staging/android/ion/ion_system_heap.c b/drivers/staging/android/ion/ion_system_heap.c
>> index bc19cdd..701eb9f 100644
>> --- a/drivers/staging/android/ion/ion_system_heap.c
>> +++ b/drivers/staging/android/ion/ion_system_heap.c
>> @@ -41,31 +41,16 @@ static inline unsigned int order_to_size(int order)
>>
>> struct ion_system_heap {
>> struct ion_heap heap;
>> - struct ion_page_pool *uncached_pools[NUM_ORDERS];
>> - struct ion_page_pool *cached_pools[NUM_ORDERS];
>> + struct ion_page_pool *pools[NUM_ORDERS];
>> };
>>
>> -/**
>> - * The page from page-pool are all zeroed before. We need do cache
>> - * clean for cached buffer. The uncached buffer are always non-cached
>> - * since it's allocated. So no need for non-cached pages.
>> - */
>> static struct page *alloc_buffer_page(struct ion_system_heap *heap,
>> struct ion_buffer *buffer,
>> unsigned long order)
>> {
>> - bool cached = ion_buffer_cached(buffer);
>> - struct ion_page_pool *pool;
>> - struct page *page;
>> + struct ion_page_pool *pool = heap->pools[order_to_index(order)];
>>
>> - if (!cached)
>> - pool = heap->uncached_pools[order_to_index(order)];
>> - else
>> - pool = heap->cached_pools[order_to_index(order)];
>> -
>> - page = ion_page_pool_alloc(pool);
>> -
>> - return page;
>> + return ion_page_pool_alloc(pool);
>> }
>>
>> static void free_buffer_page(struct ion_system_heap *heap,
>> @@ -73,7 +58,6 @@ static void free_buffer_page(struct ion_system_heap *heap,
>> {
>> struct ion_page_pool *pool;
>> unsigned int order = compound_order(page);
>> - bool cached = ion_buffer_cached(buffer);
>>
>> /* go to system */
>> if (buffer->private_flags & ION_PRIV_FLAG_SHRINKER_FREE) {
>> @@ -81,10 +65,7 @@ static void free_buffer_page(struct ion_system_heap *heap,
>> return;
>> }
>>
>> - if (!cached)
>> - pool = heap->uncached_pools[order_to_index(order)];
>> - else
>> - pool = heap->cached_pools[order_to_index(order)];
>> + pool = heap->pools[order_to_index(order)];
>>
>> ion_page_pool_free(pool, page);
>> }
>> @@ -190,8 +171,7 @@ static void ion_system_heap_free(struct ion_buffer *buffer)
>> static int ion_system_heap_shrink(struct ion_heap *heap, gfp_t gfp_mask,
>> int nr_to_scan)
>> {
>> - struct ion_page_pool *uncached_pool;
>> - struct ion_page_pool *cached_pool;
>> + struct ion_page_pool *pool;
>> struct ion_system_heap *sys_heap;
>> int nr_total = 0;
>> int i, nr_freed;
>> @@ -203,26 +183,15 @@ static int ion_system_heap_shrink(struct ion_heap *heap, gfp_t gfp_mask,
>> only_scan = 1;
>>
>> for (i = 0; i < NUM_ORDERS; i++) {
>> - uncached_pool = sys_heap->uncached_pools[i];
>> - cached_pool = sys_heap->cached_pools[i];
>> + pool = sys_heap->pools[i];
>>
>> if (only_scan) {
>> - nr_total += ion_page_pool_shrink(uncached_pool,
>> + nr_total += ion_page_pool_shrink(pool,
>> gfp_mask,
>> nr_to_scan);
>>
>> - nr_total += ion_page_pool_shrink(cached_pool,
>> - gfp_mask,
>> - nr_to_scan);
>> } else {
>> - nr_freed = ion_page_pool_shrink(uncached_pool,
>> - gfp_mask,
>> - nr_to_scan);
>> - nr_to_scan -= nr_freed;
>> - nr_total += nr_freed;
>> - if (nr_to_scan <= 0)
>> - break;
>> - nr_freed = ion_page_pool_shrink(cached_pool,
>> + nr_freed = ion_page_pool_shrink(pool,
>> gfp_mask,
>> nr_to_scan);
>> nr_to_scan -= nr_freed;
>> @@ -253,26 +222,16 @@ static int ion_system_heap_debug_show(struct ion_heap *heap, struct seq_file *s,
>> struct ion_page_pool *pool;
>>
>> for (i = 0; i < NUM_ORDERS; i++) {
>> - pool = sys_heap->uncached_pools[i];
>> + pool = sys_heap->pools[i];
>>
>> - seq_printf(s, "%d order %u highmem pages uncached %lu total\n",
>> + seq_printf(s, "%d order %u highmem pages %lu total\n",
>> pool->high_count, pool->order,
>> (PAGE_SIZE << pool->order) * pool->high_count);
>> - seq_printf(s, "%d order %u lowmem pages uncached %lu total\n",
>> + seq_printf(s, "%d order %u lowmem pages %lu total\n",
>> pool->low_count, pool->order,
>> (PAGE_SIZE << pool->order) * pool->low_count);
>> }
>>
>> - for (i = 0; i < NUM_ORDERS; i++) {
>> - pool = sys_heap->cached_pools[i];
>> -
>> - seq_printf(s, "%d order %u highmem pages cached %lu total\n",
>> - pool->high_count, pool->order,
>> - (PAGE_SIZE << pool->order) * pool->high_count);
>> - seq_printf(s, "%d order %u lowmem pages cached %lu total\n",
>> - pool->low_count, pool->order,
>> - (PAGE_SIZE << pool->order) * pool->low_count);
>> - }
>> return 0;
>> }
>>
>> @@ -285,8 +244,7 @@ static void ion_system_heap_destroy_pools(struct ion_page_pool **pools)
>> ion_page_pool_destroy(pools[i]);
>> }
>>
>> -static int ion_system_heap_create_pools(struct ion_page_pool **pools,
>> - bool cached)
>> +static int ion_system_heap_create_pools(struct ion_page_pool **pools)
>> {
>> int i;
>> gfp_t gfp_flags = low_order_gfp_flags;
>> @@ -297,7 +255,7 @@ static int ion_system_heap_create_pools(struct ion_page_pool **pools,
>> if (orders[i] > 4)
>> gfp_flags = high_order_gfp_flags;
>>
>> - pool = ion_page_pool_create(gfp_flags, orders[i], cached);
>> + pool = ion_page_pool_create(gfp_flags, orders[i]);
>> if (!pool)
>> goto err_create_pool;
>> pools[i] = pool;
>> @@ -320,18 +278,12 @@ static struct ion_heap *__ion_system_heap_create(void)
>> heap->heap.type = ION_HEAP_TYPE_SYSTEM;
>> heap->heap.flags = ION_HEAP_FLAG_DEFER_FREE;
>>
>> - if (ion_system_heap_create_pools(heap->uncached_pools, false))
>> + if (ion_system_heap_create_pools(heap->pools))
>> goto free_heap;
>>
>> - if (ion_system_heap_create_pools(heap->cached_pools, true))
>> - goto destroy_uncached_pools;
>> -
>> heap->heap.debug_show = ion_system_heap_debug_show;
>> return &heap->heap;
>>
>> -destroy_uncached_pools:
>> - ion_system_heap_destroy_pools(heap->uncached_pools);
>> -
>> free_heap:
>> kfree(heap);
>> return ERR_PTR(-ENOMEM);
>> --
>> 1.7.12.4
>>
>
>
>