[PATCH RFC 03/10] mm: page_frag: change page_frag_alloc_* API to accept align param

[Yunsheng Lin]

When page_frag_alloc_* API doesn't need data alignment, the
ALIGN() operation is unnecessary, so change page_frag_alloc_*
API to accept align param instead of align_mask param, and do
the ALIGN()'ing in the inline helper when needed.

Signed-off-by: Yunsheng Lin <linyunsheng@xxxxxxxxxx>
---
 include/linux/page_frag_cache.h | 20 ++++++++++++--------
 include/linux/skbuff.h          | 12 ++++++------
 mm/page_frag_alloc.c            |  9 ++++-----
 net/core/skbuff.c               | 12 +++++-------
 net/rxrpc/txbuf.c               |  5 +++--
 5 files changed, 30 insertions(+), 28 deletions(-)

diff --git a/include/linux/page_frag_cache.h b/include/linux/page_frag_cache.h
index 04810d8d6a7d..cc0ede0912f3 100644
--- a/include/linux/page_frag_cache.h
+++ b/include/linux/page_frag_cache.h
@@ -25,21 +25,25 @@ struct page_frag_cache {
 
 void page_frag_cache_drain(struct page_frag_cache *nc);
 void __page_frag_cache_drain(struct page *page, unsigned int count);
-void *__page_frag_alloc_align(struct page_frag_cache *nc, unsigned int fragsz,
-			      gfp_t gfp_mask, unsigned int align_mask);
+void *page_frag_alloc(struct page_frag_cache *nc, unsigned int fragsz,
+		      gfp_t gfp_mask);
+
+static inline void *__page_frag_alloc_align(struct page_frag_cache *nc,
+					    unsigned int fragsz, gfp_t gfp_mask,
+					    unsigned int align)
+{
+	nc->offset = ALIGN(nc->offset, align);
+
+	return page_frag_alloc(nc, fragsz, gfp_mask);
+}
 
 static inline void *page_frag_alloc_align(struct page_frag_cache *nc,
 					  unsigned int fragsz, gfp_t gfp_mask,
 					  unsigned int align)
 {
 	WARN_ON_ONCE(!is_power_of_2(align));
-	return __page_frag_alloc_align(nc, fragsz, gfp_mask, -align);
-}
 
-static inline void *page_frag_alloc(struct page_frag_cache *nc,
-				    unsigned int fragsz, gfp_t gfp_mask)
-{
-	return page_frag_alloc_align(nc, fragsz, gfp_mask, ~0u);
+	return __page_frag_alloc_align(nc, fragsz, gfp_mask, align);
 }
 
 void page_frag_free(void *addr);
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 7f68199fee34..074cdd29f782 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -3264,7 +3264,7 @@ static inline void skb_queue_purge(struct sk_buff_head *list)
 unsigned int skb_rbtree_purge(struct rb_root *root);
 void skb_errqueue_purge(struct sk_buff_head *list);
 
-void *__netdev_alloc_frag_align(unsigned int fragsz, unsigned int align_mask);
+void *__netdev_alloc_frag_align(unsigned int fragsz, unsigned int align);
 
 /**
  * netdev_alloc_frag - allocate a page fragment
@@ -3275,14 +3275,14 @@ void *__netdev_alloc_frag_align(unsigned int fragsz, unsigned int align_mask);
  */
 static inline void *netdev_alloc_frag(unsigned int fragsz)
 {
-	return __netdev_alloc_frag_align(fragsz, ~0u);
+	return __netdev_alloc_frag_align(fragsz, 1u);
 }
 
 static inline void *netdev_alloc_frag_align(unsigned int fragsz,
 					    unsigned int align)
 {
 	WARN_ON_ONCE(!is_power_of_2(align));
-	return __netdev_alloc_frag_align(fragsz, -align);
+	return __netdev_alloc_frag_align(fragsz, align);
 }
 
 struct sk_buff *__netdev_alloc_skb(struct net_device *dev, unsigned int length,
@@ -3342,18 +3342,18 @@ static inline void skb_free_frag(void *addr)
 	page_frag_free(addr);
 }
 
-void *__napi_alloc_frag_align(unsigned int fragsz, unsigned int align_mask);
+void *__napi_alloc_frag_align(unsigned int fragsz, unsigned int align);
 
 static inline void *napi_alloc_frag(unsigned int fragsz)
 {
-	return __napi_alloc_frag_align(fragsz, ~0u);
+	return __napi_alloc_frag_align(fragsz, 1u);
 }
 
 static inline void *napi_alloc_frag_align(unsigned int fragsz,
 					  unsigned int align)
 {
 	WARN_ON_ONCE(!is_power_of_2(align));
-	return __napi_alloc_frag_align(fragsz, -align);
+	return __napi_alloc_frag_align(fragsz, align);
 }
 
 struct sk_buff *__napi_alloc_skb(struct napi_struct *napi,
diff --git a/mm/page_frag_alloc.c b/mm/page_frag_alloc.c
index 3e3e88d9af90..39c744c892ed 100644
--- a/mm/page_frag_alloc.c
+++ b/mm/page_frag_alloc.c
@@ -63,9 +63,8 @@ void __page_frag_cache_drain(struct page *page, unsigned int count)
 }
 EXPORT_SYMBOL(__page_frag_cache_drain);
 
-void *__page_frag_alloc_align(struct page_frag_cache *nc,
-			      unsigned int fragsz, gfp_t gfp_mask,
-			      unsigned int align_mask)
+void *page_frag_alloc(struct page_frag_cache *nc, unsigned int fragsz,
+		      gfp_t gfp_mask)
 {
 	unsigned int size, offset;
 	struct page *page;
@@ -94,7 +93,7 @@ void *__page_frag_alloc_align(struct page_frag_cache *nc,
 	size = PAGE_SIZE;
 #endif
 
-	offset = ALIGN(nc->offset, -align_mask);
+	offset = nc->offset;
 	if (unlikely(offset + fragsz > size)) {
 		page = virt_to_page(nc->va);
 
@@ -131,7 +130,7 @@ void *__page_frag_alloc_align(struct page_frag_cache *nc,
 
 	return nc->va + offset;
 }
-EXPORT_SYMBOL(__page_frag_alloc_align);
+EXPORT_SYMBOL(page_frag_alloc);
 
 /*
  * Frees a page fragment allocated out of either a compound or order 0 page.
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 17617c29be2d..4c88d7f541e4 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -305,18 +305,17 @@ void napi_get_frags_check(struct napi_struct *napi)
 	local_bh_enable();
 }
 
-void *__napi_alloc_frag_align(unsigned int fragsz, unsigned int align_mask)
+void *__napi_alloc_frag_align(unsigned int fragsz, unsigned int align)
 {
 	struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);
 
 	fragsz = SKB_DATA_ALIGN(fragsz);
 
-	return __page_frag_alloc_align(&nc->page, fragsz, GFP_ATOMIC,
-				       align_mask);
+	return __page_frag_alloc_align(&nc->page, fragsz, GFP_ATOMIC, align);
 }
 EXPORT_SYMBOL(__napi_alloc_frag_align);
 
-void *__netdev_alloc_frag_align(unsigned int fragsz, unsigned int align_mask)
+void *__netdev_alloc_frag_align(unsigned int fragsz, unsigned int align)
 {
 	void *data;
 
@@ -324,15 +323,14 @@ void *__netdev_alloc_frag_align(unsigned int fragsz, unsigned int align_mask)
 	if (in_hardirq() || irqs_disabled()) {
 		struct page_frag_cache *nc = this_cpu_ptr(&netdev_alloc_cache);
 
-		data = __page_frag_alloc_align(nc, fragsz, GFP_ATOMIC,
-					       align_mask);
+		data = __page_frag_alloc_align(nc, fragsz, GFP_ATOMIC, align);
 	} else {
 		struct napi_alloc_cache *nc;
 
 		local_bh_disable();
 		nc = this_cpu_ptr(&napi_alloc_cache);
 		data = __page_frag_alloc_align(&nc->page, fragsz, GFP_ATOMIC,
-					       align_mask);
+					       align);
 		local_bh_enable();
 	}
 	return data;
diff --git a/net/rxrpc/txbuf.c b/net/rxrpc/txbuf.c
index e0679658d9de..eb640875bf07 100644
--- a/net/rxrpc/txbuf.c
+++ b/net/rxrpc/txbuf.c
@@ -32,9 +32,10 @@ struct rxrpc_txbuf *rxrpc_alloc_data_txbuf(struct rxrpc_call *call, size_t data_
 		hoff = round_up(sizeof(*whdr), data_align) - sizeof(*whdr);
 	total = hoff + sizeof(*whdr) + data_size;
 
+	data_align = max_t(size_t, data_align, L1_CACHE_BYTES);
 	mutex_lock(&call->conn->tx_data_alloc_lock);
-	buf = __page_frag_alloc_align(&call->conn->tx_data_alloc, total, gfp,
-				      ~(data_align - 1) & ~(L1_CACHE_BYTES - 1));
+	buf = page_frag_alloc_align(&call->conn->tx_data_alloc, total, gfp,
+				    data_align);
 	mutex_unlock(&call->conn->tx_data_alloc_lock);
 	if (!buf) {
 		kfree(txb);
-- 
2.33.0