[PATCH][net-next] packet: switch kvzalloc to allocate memory

[PATCH][net-next] packet: switch kvzalloc to allocate memory

[Li RongQing]

Use modern kvzalloc()/kvfree() instead of custom allocations.
And remove order argument for free_pg_vec and alloc_pg_vec,
this argument is useless to kvfree, or can get from req.

Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Signed-off-by: Li RongQing <lirongqing@baidu.com>
---
 net/packet/af_packet.c | 40 ++++++++++++----------------------------
 1 file changed, 12 insertions(+), 28 deletions(-)

diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 75c92a87e7b2..f28fcaba4f36 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -4137,52 +4137,36 @@ static const struct vm_operations_struct packet_mmap_ops = {
 	.close	=	packet_mm_close,
 };
 
-static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
-			unsigned int len)
+static void free_pg_vec(struct pgv *pg_vec, unsigned int len)
 {
 	int i;
 
 	for (i = 0; i < len; i++) {
 		if (likely(pg_vec[i].buffer)) {
-			if (is_vmalloc_addr(pg_vec[i].buffer))
-				vfree(pg_vec[i].buffer);
-			else
-				free_pages((unsigned long)pg_vec[i].buffer,
-					   order);
+			kvfree(pg_vec[i].buffer);
 			pg_vec[i].buffer = NULL;
 		}
 	}
 	kfree(pg_vec);
 }
 
-static char *alloc_one_pg_vec_page(unsigned long order)
+static char *alloc_one_pg_vec_page(unsigned long size)
 {
 	char *buffer;
-	gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
-			  __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
 
-	buffer = (char *) __get_free_pages(gfp_flags, order);
+	buffer = kvzalloc(size, GFP_KERNEL);
 	if (buffer)
 		return buffer;
 
-	/* __get_free_pages failed, fall back to vmalloc */
-	buffer = vzalloc(array_size((1 << order), PAGE_SIZE));
-	if (buffer)
-		return buffer;
+	buffer = kvzalloc(size, GFP_KERNEL | __GFP_RETRY_MAYFAIL);
 
-	/* vmalloc failed, lets dig into swap here */
-	gfp_flags &= ~__GFP_NORETRY;
-	buffer = (char *) __get_free_pages(gfp_flags, order);
-	if (buffer)
-		return buffer;
-
-	/* complete and utter failure */
-	return NULL;
+	return buffer;
 }
 
-static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
+static struct pgv *alloc_pg_vec(struct tpacket_req *req)
 {
 	unsigned int block_nr = req->tp_block_nr;
+	unsigned long size = req->tp_block_size;
 	struct pgv *pg_vec;
 	int i;
 
@@ -4191,7 +4175,7 @@ static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
 		goto out;
 
 	for (i = 0; i < block_nr; i++) {
-		pg_vec[i].buffer = alloc_one_pg_vec_page(order);
+		pg_vec[i].buffer = alloc_one_pg_vec_page(size);
 		if (unlikely(!pg_vec[i].buffer))
 			goto out_free_pgvec;
 	}
@@ -4200,7 +4184,7 @@ static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
 	return pg_vec;
 
 out_free_pgvec:
-	free_pg_vec(pg_vec, order, block_nr);
+	free_pg_vec(pg_vec, block_nr);
 	pg_vec = NULL;
 	goto out;
 }
@@ -4275,7 +4259,7 @@ static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
 
 		err = -ENOMEM;
 		order = get_order(req->tp_block_size);
-		pg_vec = alloc_pg_vec(req, order);
+		pg_vec = alloc_pg_vec(req);
 		if (unlikely(!pg_vec))
 			goto out;
 		switch (po->tp_version) {
@@ -4355,7 +4339,7 @@ static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
 	}
 
 	if (pg_vec)
-		free_pg_vec(pg_vec, order, req->tp_block_nr);
+		free_pg_vec(pg_vec, req->tp_block_nr);
 out:
 	return err;
 }
-- 
2.16.2

Re: [PATCH][net-next] packet: switch kvzalloc to allocate memory

[David Miller]

From: Li RongQing <lirongqing@baidu.com>
Date: Fri, 10 Aug 2018 18:00:00 +0800

> @@ -4275,7 +4259,7 @@ static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
>  
>  		err = -ENOMEM;
>  		order = get_order(req->tp_block_size);
> -		pg_vec = alloc_pg_vec(req, order);
> +		pg_vec = alloc_pg_vec(req);
>  		if (unlikely(!pg_vec))
>  			goto out;
>  		switch (po->tp_version) {

Variable 'order' is now unused.