stating: ion: use hot page first in pool

Hello,

I found that ion insert freed-page at the tail of list and extract at the head.

I think it is good for cache to use the most recently used page but these pages in pool are not cached memory.
So I'm not sure using hot page is better or not in this case.

What do you think about using hot page first?

-------------------------- 8< -----------------------------

From: Gioh Kim <[email protected]>
Date: Wed, 29 Oct 2014 13:44:28 +0900
Subject: [PATCH] staging: ion: use hot-page first

A page near the head is hot for cache.
This patch makes pool use hot page first.

---
 drivers/staging/android/ion/ion_page_pool.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

index 5864f3d..3d6ac4f 100644
@@ -45,10 +45,10 @@ static int ion_page_pool_add(struct ion_page_pool *pool, struct page *page)
 {
        mutex_lock(&pool->mutex);
        if (PageHighMem(page)) {
-               list_add_tail(&page->lru, &pool->high_items);
+               list_add(&page->lru, &pool->high_items);
                pool->high_count++;
        } else {
-               list_add_tail(&page->lru, &pool->low_items);
+               list_add(&page->lru, &pool->low_items);
                pool->low_count++;
        }
        mutex_unlock(&pool->mutex);

--
1.7.9.5

This is something that really needs data collection and benchmarks to see if there is actually an improvement or not.

Thanks,
Laura

Qualcomm Innovation Center, Inc. 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project

2014-10-30 오전 2:00에 Laura Abbott 이(가) 쓴 글:

Thank you for always.
I'm looking for a benchmark tool for my platform, but not founding yet.