[PATCH] iseries_veth: Remove redundant message stack lock
The iseries_veth driver keeps a stack of messages for each connection
and a lock to protect the stack. However there is also a per-connection lock
which makes the message stack lock redundant.
Remove the message stack lock and document the fact that callers of the
stack-manipulation functions must hold the connection's lock.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
diff --git a/drivers/net/iseries_veth.c b/drivers/net/iseries_veth.c
index 74ee937..231b2d2 100644
--- a/drivers/net/iseries_veth.c
+++ b/drivers/net/iseries_veth.c
@@ -143,7 +143,6 @@
struct VethCapData remote_caps;
u32 ack_timeout;
- spinlock_t msg_stack_lock;
struct veth_msg *msg_stack_head;
};
@@ -190,27 +189,23 @@
#define veth_debug(fmt, args...) do {} while (0)
#endif
+/* You must hold the connection's lock when you call this function. */
static inline void veth_stack_push(struct veth_lpar_connection *cnx,
struct veth_msg *msg)
{
- unsigned long flags;
-
- spin_lock_irqsave(&cnx->msg_stack_lock, flags);
msg->next = cnx->msg_stack_head;
cnx->msg_stack_head = msg;
- spin_unlock_irqrestore(&cnx->msg_stack_lock, flags);
}
+/* You must hold the connection's lock when you call this function. */
static inline struct veth_msg *veth_stack_pop(struct veth_lpar_connection *cnx)
{
- unsigned long flags;
struct veth_msg *msg;
- spin_lock_irqsave(&cnx->msg_stack_lock, flags);
msg = cnx->msg_stack_head;
if (msg)
cnx->msg_stack_head = cnx->msg_stack_head->next;
- spin_unlock_irqrestore(&cnx->msg_stack_lock, flags);
+
return msg;
}
@@ -645,7 +640,6 @@
cnx->msgs = msgs;
memset(msgs, 0, VETH_NUMBUFFERS * sizeof(struct veth_msg));
- spin_lock_init(&cnx->msg_stack_lock);
for (i = 0; i < VETH_NUMBUFFERS; i++) {
msgs[i].token = i;
