From 4ec441df25a686518fb369086e2b34a1cedaa6c9 Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Wed, 17 Feb 2016 11:02:43 -0800 Subject: i40e/i40evf: Break up xmit_descriptor_count from maybe_stop_tx In an upcoming patch I would like to have access to the descriptor count used for the data portion of the frame. For this reason I am splitting up the descriptor count function from the function that stops the ring. Also in order to try and reduce unnecessary duplication of code I am moving the slow-path portions of the code out of being inline calls so that we can just jump to them and process them instead of having to build them into each function that calls them. Signed-off-by: Alexander Duyck Tested-by: Andrew Bowers Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/i40e/i40e_txrx.h | 44 +++++++++++++++++++++++++++-- 1 file changed, 42 insertions(+), 2 deletions(-) (limited to 'drivers/net/ethernet/intel/i40e/i40e_txrx.h') diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.h b/drivers/net/ethernet/intel/i40e/i40e_txrx.h index fde5f42524fb..5dbc958293f7 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_txrx.h +++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.h @@ -331,13 +331,12 @@ int i40e_napi_poll(struct napi_struct *napi, int budget); void i40e_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb, struct i40e_tx_buffer *first, u32 tx_flags, const u8 hdr_len, u32 td_cmd, u32 td_offset); -int i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size); -int i40e_xmit_descriptor_count(struct sk_buff *skb, struct i40e_ring *tx_ring); int i40e_tx_prepare_vlan_flags(struct sk_buff *skb, struct i40e_ring *tx_ring, u32 *flags); #endif void i40e_force_wb(struct i40e_vsi *vsi, struct i40e_q_vector *q_vector); u32 i40e_get_tx_pending(struct i40e_ring *ring, bool in_sw); +int __i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size); /** * i40e_get_head - Retrieve head from head writeback @@ -352,4 +351,45 @@ static inline u32 i40e_get_head(struct i40e_ring *tx_ring) return le32_to_cpu(*(volatile __le32 *)head); } + +/** + * i40e_xmit_descriptor_count - calculate number of Tx descriptors needed + * @skb: send buffer + * @tx_ring: ring to send buffer on + * + * Returns number of data descriptors needed for this skb. Returns 0 to indicate + * there is not enough descriptors available in this ring since we need at least + * one descriptor. + **/ +static inline int i40e_xmit_descriptor_count(struct sk_buff *skb) +{ + const struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[0]; + unsigned int nr_frags = skb_shinfo(skb)->nr_frags; + int count = 0, size = skb_headlen(skb); + + for (;;) { + count += TXD_USE_COUNT(size); + + if (!nr_frags--) + break; + + size = skb_frag_size(frag++); + } + + return count; +} + +/** + * i40e_maybe_stop_tx - 1st level check for Tx stop conditions + * @tx_ring: the ring to be checked + * @size: the size buffer we want to assure is available + * + * Returns 0 if stop is not needed + **/ +static inline int i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size) +{ + if (likely(I40E_DESC_UNUSED(tx_ring) >= size)) + return 0; + return __i40e_maybe_stop_tx(tx_ring, size); +} #endif /* _I40E_TXRX_H_ */ -- cgit v1.2.3