mm: optimize for cma free time

PD#165878: mm: optimize for cma free time

Fix bad parameter error and using high efficient free method.

Change-Id: I5fa1373644a373b3dd94775c5c29891f7f6f7420
Signed-off-by: tao zeng <tao.zeng@amlogic.com>

diff --git a/drivers/amlogic/memory_ext/aml_cma.c b/drivers/amlogic/memory_ext/aml_cma.c
index dceb78a..5554619 100644 (file)
--- a/drivers/amlogic/memory_ext/aml_cma.c
+++ b/drivers/amlogic/memory_ext/aml_cma.c
@@ -684,45 +684,16 @@ static int __aml_cma_free_check(struct page *page, int order, unsigned int *cnt)
        return 0;
 }
 
-static inline unsigned long
-__find_buddy_index(unsigned long page_idx, unsigned int order)
+static int aml_cma_get_page_order(unsigned long pfn)
 {
-       return page_idx ^ (1 << order);
-}
+       int i, mask = 1;
 
-static int aml_cma_get_page_order(struct page *page, int cur_order)
-{
-       int order, ret = 0;
-       unsigned long page_idx, buddy_idx, combined_idx, flags;
-       struct page *buddy, *raw;
-       struct zone *zone;
-
-       /*
-        * same as __free_one_page, but we only need to find out freed buddy
-        * and it's order of it.
-        */
-       buddy = page;
-       raw   = page;
-       page_idx = page_to_pfn(page) & ((1 << MAX_ORDER) - 1);
-       zone = page_zone(page);
-       spin_lock_irqsave(&zone->lock, flags);
-       for (order = cur_order; order < MAX_ORDER; order++) {
-               buddy_idx = __find_buddy_index(page_idx, order);
-               buddy = page + (buddy_idx - page_idx);
-               combined_idx = buddy_idx & page_idx;
-               page = page + (combined_idx - page_idx);
-               page_idx = combined_idx;
-               if (PageBuddy(buddy)) {
-                       ret = page_private(buddy);
+       for (i = 0; i < (MAX_ORDER - 1); i++) {
+               if (pfn & (mask << i))
                        break;
-               }
        }
-       spin_unlock_irqrestore(&zone->lock, flags);
 
-       WARN(ret >= MAX_ORDER, "%s page:%lx, buddy:%lx:%ld, corder:%d,ret:%d\n",
-               __func__, page_to_pfn(raw), page_to_pfn(buddy),
-               page_private(buddy), cur_order, ret);
-       return 0;
+       return i;
 }
 
 void aml_cma_free(unsigned long pfn, unsigned int nr_pages)
@@ -734,26 +705,7 @@ void aml_cma_free(unsigned long pfn, unsigned int nr_pages)
 
        while (nr_pages) {
                page = pfn_to_page(pfn);
-               batch = (1 << start_order);
-               if (__aml_cma_free_check(page, start_order, &count))
-                       break;
-
-               __free_pages(page, start_order);
-               free_order = aml_cma_get_page_order(page, start_order);
-               pr_debug("pages:%4d, free:%2d, start:%2d, batch:%4d, pfn:%lx\n",
-                       nr_pages, free_order,
-                       start_order, batch, pfn);
-               nr_pages -= batch;
-               pfn += batch;
-               /*
-                * since pages are contigunous, and it's buddy already has large
-                * order, we can try to free same oder as free_order to get more
-                * quickly free speed.
-                */
-               if (free_order < 0) {
-                       start_order = 0;
-                       continue;
-               }
+               free_order = aml_cma_get_page_order(pfn);
                if (nr_pages >= (1 << free_order)) {
                        start_order = free_order;
                } else {
@@ -763,6 +715,15 @@ void aml_cma_free(unsigned long pfn, unsigned int nr_pages)
                                start_order++;
                        start_order--;
                }
+               batch = (1 << start_order);
+               if (__aml_cma_free_check(page, start_order, &count))
+                       break;
+               __free_pages(page, start_order);
+               pr_debug("pages:%4d, free:%2d, start:%2d, batch:%4d, pfn:%lx\n",
+                       nr_pages, free_order,
+                       start_order, batch, pfn);
+               nr_pages -= batch;
+               pfn += batch;
        }
        WARN(count != 0, "%d pages are still in use!\n", count);
 }