From patchwork Thu Sep 11 07:51:46 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hiroshi Shimamoto X-Patchwork-Id: 339 Return-Path: X-Original-To: patchwork@dpdk.org Delivered-To: patchwork@dpdk.org Received: from [92.243.14.124] (localhost [IPv6:::1]) by dpdk.org (Postfix) with ESMTP id 4C7BE5909; Thu, 11 Sep 2014 09:54:44 +0200 (CEST) Received: from tyo202.gate.nec.co.jp (TYO202.gate.nec.co.jp [210.143.35.52]) by dpdk.org (Postfix) with ESMTP id 51B845901 for ; Thu, 11 Sep 2014 09:54:42 +0200 (CEST) Received: from mailgate3.nec.co.jp ([10.7.69.195]) by tyo202.gate.nec.co.jp (8.13.8/8.13.4) with ESMTP id s8B7xr3g014659 for ; Thu, 11 Sep 2014 16:59:53 +0900 (JST) Received: from mailsv.nec.co.jp (imss62.nec.co.jp [10.7.69.157]) by mailgate3.nec.co.jp (8.11.7/3.7W-MAILGATE-NEC) with ESMTP id s8B7xqx10649 for ; Thu, 11 Sep 2014 16:59:52 +0900 (JST) Received: from mail03.kamome.nec.co.jp (mail03.kamome.nec.co.jp [10.25.43.7]) by mailsv.nec.co.jp (8.13.8/8.13.4) with ESMTP id s8B7xqi9022757 for ; Thu, 11 Sep 2014 16:59:52 +0900 (JST) Received: from bpxc99gp.gisp.nec.co.jp ([10.38.151.145] [10.38.151.145]) by mail03.kamome.nec.co.jp with ESMTP id BT-MMP-1868130; Thu, 11 Sep 2014 16:51:48 +0900 Received: from BPXM14GP.gisp.nec.co.jp ([169.254.1.238]) by BPXC17GP.gisp.nec.co.jp ([10.38.151.145]) with mapi id 14.02.0328.011; Thu, 11 Sep 2014 16:51:47 +0900 From: Hiroshi Shimamoto To: "dev@dpdk.org" Thread-Topic: [memnic PATCH 6/7] pmd: add branch hint in recv/xmit Thread-Index: Ac/NlTGBVAvPfNK8SxSfZgzquF035A== Date: Thu, 11 Sep 2014 07:51:46 +0000 Message-ID: <7F861DC0615E0C47A872E6F3C5FCDDBD011A99A8@BPXM14GP.gisp.nec.co.jp> Accept-Language: ja-JP, en-US Content-Language: ja-JP X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.205.5.123] MIME-Version: 1.0 Cc: Hayato Momma Subject: [dpdk-dev] [memnic PATCH 6/7] pmd: add branch hint in recv/xmit X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" From: Hiroshi Shimamoto To reduce instruction cache miss, add branch condition hints into recv/xmit functions. This improves a bit performance. We can see performance improvements with memnic-tester. Using Xeon E5-2697 v2 @ 2.70GHz, 4 vCPU. size | before | after 64 | 5.54Mpps | 5.55Mpps 128 | 5.46Mpps | 5.44Mpps 256 | 5.21Mpps | 5.22Mpps 512 | 4.50Mpps | 4.52Mpps 1024 | 3.71Mpps | 3.73Mpps 1280 | 3.21Mpps | 3.22Mpps 1518 | 2.92Mpps | 2.93Mpps Signed-off-by: Hiroshi Shimamoto Reviewed-by: Hayato Momma --- pmd/pmd_memnic.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/pmd/pmd_memnic.c b/pmd/pmd_memnic.c index dbe5033..cc0ae25 100644 --- a/pmd/pmd_memnic.c +++ b/pmd/pmd_memnic.c @@ -289,26 +289,26 @@ static uint16_t memnic_recv_pkts(void *rx_queue, int idx, next; struct rte_eth_stats *st = &adapter->stats[rte_lcore_id()]; - if (!adapter->nic->hdr.valid) + if (unlikely(!adapter->nic->hdr.valid)) return 0; pkts = bytes = errs = 0; idx = adapter->up_idx; for (nr = 0; nr < nb_pkts; nr++) { p = &data->packets[idx]; - if (p->status != MEMNIC_PKT_ST_FILLED) + if (unlikely(p->status != MEMNIC_PKT_ST_FILLED)) break; /* prefetch the next area */ next = idx; - if (++next >= MEMNIC_NR_PACKET) + if (unlikely(++next >= MEMNIC_NR_PACKET)) next = 0; rte_prefetch0(&data->packets[next]); - if (p->len > framesz) { + if (unlikely(p->len > framesz)) { errs++; goto drop; } mb = rte_pktmbuf_alloc(adapter->mp); - if (!mb) + if (unlikely(!mb)) break; rte_memcpy(rte_pktmbuf_mtod(mb, void *), p->data, p->len); @@ -350,7 +350,7 @@ static uint16_t memnic_xmit_pkts(void *tx_queue, uint64_t pkts, bytes, errs; uint32_t framesz = adapter->framesz; - if (!adapter->nic->hdr.valid) + if (unlikely(!adapter->nic->hdr.valid)) return 0; pkts = bytes = errs = 0; @@ -360,7 +360,7 @@ static uint16_t memnic_xmit_pkts(void *tx_queue, struct rte_mbuf *sg; void *ptr; - if (pkt_len > framesz) { + if (unlikely(pkt_len > framesz)) { errs++; break; } @@ -379,7 +379,7 @@ retry: goto retry; } - if (idx != ACCESS_ONCE(adapter->down_idx)) { + if (unlikely(idx != ACCESS_ONCE(adapter->down_idx))) { /* * host freed this and got false positive, * need to recover the status and retry. @@ -388,7 +388,7 @@ retry: goto retry; } - if (++idx >= MEMNIC_NR_PACKET) + if (unlikely(++idx >= MEMNIC_NR_PACKET)) idx = 0; adapter->down_idx = idx;