diff mbox series

[v4,net-next,11/11] skbuff: queue NAPI_MERGED_FREE skbs into NAPI cache instead of freeing

Message ID 20210210162732.80467-12-alobakin@pm.me (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series skbuff: introduce skbuff_heads bulking and reusing | expand

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netdev/build_32bit fail Errors and warnings before: 8493 this patch: 8493
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netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 58 lines checked
netdev/build_allmodconfig_warn fail Errors and warnings before: 8891 this patch: 8891
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netdev/stable success Stable not CCed

Commit Message

Alexander Lobakin Feb. 10, 2021, 4:31 p.m. UTC 
napi_frags_finish() and napi_skb_finish() can only be called inside
NAPI Rx context, so we can feed NAPI cache with skbuff_heads that
got NAPI_MERGED_FREE verdict instead of immediate freeing.
Replace __kfree_skb() with __kfree_skb_defer() in napi_skb_finish()
and move napi_skb_free_stolen_head() to skbuff.c, so it can drop skbs
to NAPI cache.
As many drivers call napi_alloc_skb()/napi_get_frags() on their
receive path, this becomes especially useful.

Signed-off-by: Alexander Lobakin <alobakin@pm.me>
---
 include/linux/skbuff.h |  1 +
 net/core/dev.c         |  9 +--------
 net/core/skbuff.c      | 12 +++++++++---
 3 files changed, 11 insertions(+), 11 deletions(-)
diff mbox series

Patch

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 906122eac82a..6d0a33d1c0db 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -2921,6 +2921,7 @@  static inline struct sk_buff *napi_alloc_skb(struct napi_struct *napi,
 }
 void napi_consume_skb(struct sk_buff *skb, int budget);
 
+void napi_skb_free_stolen_head(struct sk_buff *skb);
 void __kfree_skb_defer(struct sk_buff *skb);
 
 /**
diff --git a/net/core/dev.c b/net/core/dev.c
index 7134ae2fc0db..f04877295b4f 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -6094,13 +6094,6 @@  struct packet_offload *gro_find_complete_by_type(__be16 type)
 }
 EXPORT_SYMBOL(gro_find_complete_by_type);
 
-static void napi_skb_free_stolen_head(struct sk_buff *skb)
-{
-	skb_dst_drop(skb);
-	skb_ext_put(skb);
-	kmem_cache_free(skbuff_head_cache, skb);
-}
-
 static gro_result_t napi_skb_finish(struct napi_struct *napi,
 				    struct sk_buff *skb,
 				    gro_result_t ret)
@@ -6114,7 +6107,7 @@  static gro_result_t napi_skb_finish(struct napi_struct *napi,
 		if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD)
 			napi_skb_free_stolen_head(skb);
 		else
-			__kfree_skb(skb);
+			__kfree_skb_defer(skb);
 		break;
 
 	case GRO_HELD:
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index ac6e0172f206..9ff701afa837 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -917,9 +917,6 @@  static void napi_skb_cache_put(struct sk_buff *skb)
 	struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);
 	u32 i;
 
-	/* drop skb->head and call any destructors for packet */
-	skb_release_all(skb);
-
 	kasan_poison_object_data(skbuff_head_cache, skb);
 	nc->skb_cache[nc->skb_count++] = skb;
 
@@ -936,6 +933,14 @@  static void napi_skb_cache_put(struct sk_buff *skb)
 
 void __kfree_skb_defer(struct sk_buff *skb)
 {
+	skb_release_all(skb);
+	napi_skb_cache_put(skb);
+}
+
+void napi_skb_free_stolen_head(struct sk_buff *skb)
+{
+	skb_dst_drop(skb);
+	skb_ext_put(skb);
 	napi_skb_cache_put(skb);
 }
 
@@ -961,6 +966,7 @@  void napi_consume_skb(struct sk_buff *skb, int budget)
 		return;
 	}
 
+	skb_release_all(skb);
 	napi_skb_cache_put(skb);
 }
 EXPORT_SYMBOL(napi_consume_skb);