net: page_pool: use in_softirq() instead

[ Upstream commit 542bcea4be866b14b3a5c8e90773329066656c43 ]

We use BH context only for synchronization, so we don't care if it's
actually serving softirq or not.

As a side node, in case of threaded NAPI, in_serving_softirq() will
return false because it's in process context with BH off, making
page_pool_recycle_in_cache() unreachable.

Signed-off-by: Qingfang DENG <qingfang.deng@siflower.com.cn>
Tested-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: 368d3cb406cd ("page_pool: fix inconsistency for page_pool_ring_[un]lock()")
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/include/net/page_pool.h b/include/net/page_pool.h
index 813c934..34bf531 100644 (file)
--- a/include/net/page_pool.h
+++ b/include/net/page_pool.h
@@ -386,7 +386,7 @@ static inline void page_pool_nid_changed(struct page_pool *pool, int new_nid)
 static inline void page_pool_ring_lock(struct page_pool *pool)
        __acquires(&pool->ring.producer_lock)
 {
-       if (in_serving_softirq())
+       if (in_softirq())
                spin_lock(&pool->ring.producer_lock);
        else
                spin_lock_bh(&pool->ring.producer_lock);
@@ -395,7 +395,7 @@ static inline void page_pool_ring_lock(struct page_pool *pool)
 static inline void page_pool_ring_unlock(struct page_pool *pool)
        __releases(&pool->ring.producer_lock)
 {
-       if (in_serving_softirq())
+       if (in_softirq())
                spin_unlock(&pool->ring.producer_lock);
        else
                spin_unlock_bh(&pool->ring.producer_lock);

diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index 9b203d8..193c187 100644 (file)
--- a/net/core/page_pool.c
+++ b/net/core/page_pool.c
@@ -511,8 +511,8 @@ static void page_pool_return_page(struct page_pool *pool, struct page *page)
 static bool page_pool_recycle_in_ring(struct page_pool *pool, struct page *page)
 {
        int ret;
-       /* BH protection not needed if current is serving softirq */
-       if (in_serving_softirq())
+       /* BH protection not needed if current is softirq */
+       if (in_softirq())
                ret = ptr_ring_produce(&pool->ring, page);
        else
                ret = ptr_ring_produce_bh(&pool->ring, page);
@@ -570,7 +570,7 @@ __page_pool_put_page(struct page_pool *pool, struct page *page,
                        page_pool_dma_sync_for_device(pool, page,
                                                      dma_sync_size);
 
-               if (allow_direct && in_serving_softirq() &&
+               if (allow_direct && in_softirq() &&
                    page_pool_recycle_in_cache(page, pool))
                        return NULL;