On 05/08/15 07:28, Liang, Cunming wrote:
> Hi Zoltan,
>
>> -----Original Message-----
>> From: Zoltan Kiss [mailto:zoltan.kiss at linaro.org]
>> Sent: Wednesday, August 05, 2015 12:26 AM
>> To: Liang, Cunming; dev at dpdk.org
>> Cc: Ananyev, Konstantin
>> Subject: Re: [PATCH v3] ixgbe: remove vector pmd burst size restriction
>>
>>
>>
>> On 04/08/15 12:47, Cunming Liang wrote:
>>> On receive side, the burst size now floor aligns to RTE_IXGBE_DESCS_PER_LOOP
>> power of 2.
>>> According to this rule, the burst size less than 4 still won't receive
>>> anything.
>>> (Before this change, the burst size less than 32 can't receive anything.)
>>> _recv_*_pkts_vec returns no more than 32(RTE_IXGBE_RXQ_REARM_THRESH)
>> packets.
>>>
>>> On transmit side, the max burst size no longer bind with a constant,
>>> however it
>> still
>>> require to check the cross tx_rs_thresh violation.
>>>
>>> There's no obvious performance drop found on both recv_pkts_vec
>>> and recv_scattered_pkts_vec on burst size 32.
>>>
>>> Signed-off-by: Cunming Liang <cunming.liang at intel.com>
>>> ---
>>> v3 change:
>>> - reword the init print log
>>>
>>> v2 change:
>>> - keep max rx burst size in 32
>>> - reword some comments
>>>
>>> drivers/net/ixgbe/ixgbe_rxtx.c | 4 +++-
>>> drivers/net/ixgbe/ixgbe_rxtx.h | 5 ++---
>>> drivers/net/ixgbe/ixgbe_rxtx_vec.c | 39
>> +++++++++++++++++++++-----------------
>>> 3 files changed, 27 insertions(+), 21 deletions(-)
>>>
>>> diff --git a/drivers/net/ixgbe/ixgbe_rxtx.c b/drivers/net/ixgbe/ixgbe_rxtx.c
>>> index 91023b9..03eb45d 100644
>>> --- a/drivers/net/ixgbe/ixgbe_rxtx.c
>>> +++ b/drivers/net/ixgbe/ixgbe_rxtx.c
>>> @@ -4008,7 +4008,9 @@ ixgbe_set_rx_function(struct rte_eth_dev *dev)
>>> */
>>> } else if (adapter->rx_vec_allowed) {
>>> PMD_INIT_LOG(DEBUG, "Vector rx enabled, please make sure RX "
>>> - "burst size no less than 32.");
>>> + "burst size no less than %d (port=%d).",
>>> + RTE_IXGBE_DESCS_PER_LOOP,
>>> + dev->data->port_id);
>>
>> A tab seems to be missing from the indentation, otherwise:
>>
>> Reviewed-by: Zoltan Kiss <zoltan.kiss at linaro.org>
>>
> Thanks for the review. I double checked indentation agian, it looks fine.
> 1st string line 4x/tab intention + space alignment, the other variable lines
> 3x/tab indentation + space alignment.
> According to the 'coding_style.rst' Indentation section - 'As with all style
> guideline, code should match style already in use in an existing file.'
> The style keeps the same as its following condition check. It passes
> 'checkpatch.pl' checking as well.
Sorry for the noise, I was confused because the string is indented to
the start of itself, while the other parameters to the opening bracket.
>
> Thanks,
> /Steve
>>>
>>> dev->rx_pkt_burst = ixgbe_recv_pkts_vec;
>>> } else if (adapter->rx_bulk_alloc_allowed) {
>>> diff --git a/drivers/net/ixgbe/ixgbe_rxtx.h b/drivers/net/ixgbe/ixgbe_rxtx.h
>>> index 113682a..b9eca67 100644
>>> --- a/drivers/net/ixgbe/ixgbe_rxtx.h
>>> +++ b/drivers/net/ixgbe/ixgbe_rxtx.h
>>> @@ -47,9 +47,8 @@
>>> (uint64_t) ((mb)->buf_physaddr + RTE_PKTMBUF_HEADROOM)
>>>
>>> #ifdef RTE_IXGBE_INC_VECTOR
>>> -#define RTE_IXGBE_VPMD_RX_BURST 32
>>> -#define RTE_IXGBE_VPMD_TX_BURST 32
>>> -#define RTE_IXGBE_RXQ_REARM_THRESH RTE_IXGBE_VPMD_RX_BURST
>>> +#define RTE_IXGBE_RXQ_REARM_THRESH 32
>>> +#define RTE_IXGBE_MAX_RX_BURST
>> RTE_IXGBE_RXQ_REARM_THRESH
>>> #define RTE_IXGBE_TX_MAX_FREE_BUF_SZ 64
>>> #endif
>>>
>>> diff --git a/drivers/net/ixgbe/ixgbe_rxtx_vec.c
>> b/drivers/net/ixgbe/ixgbe_rxtx_vec.c
>>> index cf25a53..2ca0e4c 100644
>>> --- a/drivers/net/ixgbe/ixgbe_rxtx_vec.c
>>> +++ b/drivers/net/ixgbe/ixgbe_rxtx_vec.c
>>> @@ -245,13 +245,13 @@ desc_to_olflags_v(__m128i descs[4], struct
>> rte_mbuf **rx_pkts)
>>> #endif
>>>
>>> /*
>>> - * vPMD receive routine, now only accept (nb_pkts ==
>> RTE_IXGBE_VPMD_RX_BURST)
>>> - * in one loop
>>> + * vPMD raw receive routine, only accept(nb_pkts >=
>> RTE_IXGBE_DESCS_PER_LOOP)
>>> *
>>> * Notice:
>>> - * - nb_pkts < RTE_IXGBE_VPMD_RX_BURST, just return no packet
>>> - * - nb_pkts > RTE_IXGBE_VPMD_RX_BURST, only scan
>> RTE_IXGBE_VPMD_RX_BURST
>>> + * - nb_pkts < RTE_IXGBE_DESCS_PER_LOOP, just return no packet
>>> + * - nb_pkts > RTE_IXGBE_MAX_RX_BURST, only scan
>> RTE_IXGBE_MAX_RX_BURST
>>> * numbers of DD bit
>>> + * - floor align nb_pkts to a RTE_IXGBE_DESC_PER_LOOP power-of-two
>>> * - don't support ol_flags for rss and csum err
>>> */
>>> static inline uint16_t
>>> @@ -286,8 +286,11 @@ _recv_raw_pkts_vec(struct ixgbe_rx_queue *rxq,
>> struct rte_mbuf **rx_pkts,
>>> __m128i dd_check, eop_check;
>>> #endif /* RTE_NEXT_ABI */
>>>
>>> - if (unlikely(nb_pkts < RTE_IXGBE_VPMD_RX_BURST))
>>> - return 0;
>>> + /* nb_pkts shall be less equal than RTE_IXGBE_MAX_RX_BURST */
>>> + nb_pkts = RTE_MIN(nb_pkts, RTE_IXGBE_MAX_RX_BURST);
>>> +
>>> + /* nb_pkts has to be floor-aligned to RTE_IXGBE_DESCS_PER_LOOP */
>>> + nb_pkts = RTE_ALIGN_FLOOR(nb_pkts, RTE_IXGBE_DESCS_PER_LOOP);
>>>
>>> /* Just the act of getting into the function from the application is
>>> * going to cost about 7 cycles */
>>> @@ -356,7 +359,7 @@ _recv_raw_pkts_vec(struct ixgbe_rx_queue *rxq,
>> struct rte_mbuf **rx_pkts,
>>> * D. fill info. from desc to mbuf
>>> */
>>> #endif /* RTE_NEXT_ABI */
>>> - for (pos = 0, nb_pkts_recd = 0; pos < RTE_IXGBE_VPMD_RX_BURST;
>>> + for (pos = 0, nb_pkts_recd = 0; pos < nb_pkts;
>>> pos += RTE_IXGBE_DESCS_PER_LOOP,
>>> rxdp += RTE_IXGBE_DESCS_PER_LOOP) {
>>> #ifdef RTE_NEXT_ABI
>>> @@ -518,13 +521,13 @@ _recv_raw_pkts_vec(struct ixgbe_rx_queue *rxq,
>> struct rte_mbuf **rx_pkts,
>>> }
>>>
>>> /*
>>> - * vPMD receive routine, now only accept (nb_pkts ==
>> RTE_IXGBE_VPMD_RX_BURST)
>>> - * in one loop
>>> + * vPMD receive routine, only accept(nb_pkts >=
>> RTE_IXGBE_DESCS_PER_LOOP)
>>> *
>>> * Notice:
>>> - * - nb_pkts < RTE_IXGBE_VPMD_RX_BURST, just return no packet
>>> - * - nb_pkts > RTE_IXGBE_VPMD_RX_BURST, only scan
>> RTE_IXGBE_VPMD_RX_BURST
>>> + * - nb_pkts < RTE_IXGBE_DESCS_PER_LOOP, just return no packet
>>> + * - nb_pkts > RTE_IXGBE_MAX_RX_BURST, only scan
>> RTE_IXGBE_MAX_RX_BURST
>>> * numbers of DD bit
>>> + * - floor align nb_pkts to a RTE_IXGBE_DESC_PER_LOOP power-of-two
>>> * - don't support ol_flags for rss and csum err
>>> */
>>> uint16_t
>>> @@ -538,12 +541,11 @@ static inline uint16_t
>>> reassemble_packets(struct ixgbe_rx_queue *rxq, struct rte_mbuf **rx_bufs,
>>> uint16_t nb_bufs, uint8_t *split_flags)
>>> {
>>> - struct rte_mbuf *pkts[RTE_IXGBE_VPMD_RX_BURST]; /*finished pkts*/
>>> + struct rte_mbuf *pkts[nb_bufs]; /*finished pkts*/
>>> struct rte_mbuf *start = rxq->pkt_first_seg;
>>> struct rte_mbuf *end = rxq->pkt_last_seg;
>>> unsigned pkt_idx, buf_idx;
>>>
>>> -
>>> for (buf_idx = 0, pkt_idx = 0; buf_idx < nb_bufs; buf_idx++) {
>>> if (end != NULL) {
>>> /* processing a split packet */
>>> @@ -603,14 +605,17 @@ reassemble_packets(struct ixgbe_rx_queue *rxq,
>> struct rte_mbuf **rx_bufs,
>>> *
>>> * Notice:
>>> * - don't support ol_flags for rss and csum err
>>> - * - now only accept (nb_pkts == RTE_IXGBE_VPMD_RX_BURST)
>>> + * - nb_pkts < RTE_IXGBE_DESCS_PER_LOOP, just return no packet
>>> + * - nb_pkts > RTE_IXGBE_MAX_RX_BURST, only scan
>> RTE_IXGBE_MAX_RX_BURST
>>> + * numbers of DD bit
>>> + * - floor align nb_pkts to a RTE_IXGBE_DESC_PER_LOOP power-of-two
>>> */
>>> uint16_t
>>> ixgbe_recv_scattered_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
>>> uint16_t nb_pkts)
>>> {
>>> struct ixgbe_rx_queue *rxq = rx_queue;
>>> - uint8_t split_flags[RTE_IXGBE_VPMD_RX_BURST] = {0};
>>> + uint8_t split_flags[RTE_IXGBE_MAX_RX_BURST] = {0};
>>>
>>> /* get some new buffers */
>>> uint16_t nb_bufs = _recv_raw_pkts_vec(rxq, rx_pkts, nb_pkts,
>>> @@ -735,8 +740,8 @@ ixgbe_xmit_pkts_vec(void *tx_queue, struct rte_mbuf
>> **tx_pkts,
>>> uint64_t rs = IXGBE_ADVTXD_DCMD_RS|DCMD_DTYP_FLAGS;
>>> int i;
>>>
>>> - if (unlikely(nb_pkts > RTE_IXGBE_VPMD_TX_BURST))
>>> - nb_pkts = RTE_IXGBE_VPMD_TX_BURST;
>>> + /* cross rx_thresh boundary is not allowed */
>>> + nb_pkts = RTE_MIN(nb_pkts, txq->tx_rs_thresh);
>>>
>>> if (txq->nb_tx_free < txq->tx_free_thresh)
>>> ixgbe_tx_free_bufs(txq);
>>>
