I do not see how one can effectively use skb_insert() without holding
some kind of lock. Otherwise other cpus could have changed the list
right before we have a chance of acquiring list->lock.
Only existing user is in drivers/infiniband/hw/nes/nes_mgt.c and this
one probably meant to use __skb_insert() since it appears nesqp->pau_list
is protected by nesqp->pau_lock. This looks like nesqp->pau_lock
could be removed, since nesqp->pau_list.lock could be used instead.
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Cc: Faisal Latif <faisal.latif@xxxxxxxxx>
Cc: Doug Ledford <dledford@xxxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxx>
Cc: linux-rdma <linux-rdma@xxxxxxxxxxxxxxx>
---
drivers/infiniband/hw/nes/nes_mgt.c | 4 ++--
include/linux/skbuff.h | 2 --
net/core/skbuff.c | 22 ----------------------
3 files changed, 2 insertions(+), 26 deletions(-)
diff --git a/drivers/infiniband/hw/nes/nes_mgt.c b/drivers/infiniband/hw/nes/nes_mgt.c
index fc0c191014e908eea32d752f3499295ef143aa0a..cc4dce5c3e5f6d99fc44fcde7334e70ac7a33002 100644
--- a/drivers/infiniband/hw/nes/nes_mgt.c
+++ b/drivers/infiniband/hw/nes/nes_mgt.c
@@ -551,14 +551,14 @@ static void queue_fpdus(struct sk_buff *skb, struct nes_vnic *nesvnic, struct ne
/* Queue skb by sequence number */
if (skb_queue_len(&nesqp->pau_list) == 0) {
- skb_queue_head(&nesqp->pau_list, skb);
+ __skb_queue_head(&nesqp->pau_list, skb);
} else {
skb_queue_walk(&nesqp->pau_list, tmpskb) {
cb = (struct nes_rskb_cb *)&tmpskb->cb[0];
if (before(seqnum, cb->seqnum))
break;
}
- skb_insert(tmpskb, skb, &nesqp->pau_list);
+ __skb_insert(skb, tmpskb->prev, tmpskb, &nesqp->pau_list);
}
if (nesqp->pau_state == PAU_READY)
process_it = true;
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index f17a7452ac7bf47ef4bcf89840bba165cee6f50a..73902acf2b71c8800d81b744a936a7420f33b459 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -1749,8 +1749,6 @@ static inline void skb_queue_head_init_class(struct sk_buff_head *list,
* The "__skb_xxxx()" functions are the non-atomic ones that
* can only be called with interrupts disabled.
*/
-void skb_insert(struct sk_buff *old, struct sk_buff *newsk,
- struct sk_buff_head *list);
static inline void __skb_insert(struct sk_buff *newsk,
struct sk_buff *prev, struct sk_buff *next,
struct sk_buff_head *list)
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 9a8a72cefe9b94d3821b9cc5ba5bba647ae51267..02cd7ae3d0fb26ef0a8b006390154fdefd0d292f 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -2990,28 +2990,6 @@ void skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head
}
EXPORT_SYMBOL(skb_append);
-/**
- * skb_insert - insert a buffer
- * @old: buffer to insert before
- * @newsk: buffer to insert
- * @list: list to use
- *
- * Place a packet before a given packet in a list. The list locks are
- * taken and this function is atomic with respect to other list locked
- * calls.
- *
- * A buffer cannot be placed on two lists at the same time.
- */
-void skb_insert(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&list->lock, flags);
- __skb_insert(newsk, old->prev, old, list);
- spin_unlock_irqrestore(&list->lock, flags);
-}
-EXPORT_SYMBOL(skb_insert);
-
static inline void skb_split_inside_header(struct sk_buff *skb,
struct sk_buff* skb1,
const u32 len, const int pos)
--
2.20.0.rc0.387.gc7a69e6b6c-goog
