From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id D9C1C47092; Fri, 19 Dec 2025 18:28:25 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 00ABE40B91; Fri, 19 Dec 2025 18:26:39 +0100 (CET) Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.15]) by mails.dpdk.org (Postfix) with ESMTP id C43AA40A80 for ; Fri, 19 Dec 2025 18:26:35 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1766165196; x=1797701196; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=O/a6e91iPIBiHDveSuFudFFGioIGcaohrWlwFZZHCbQ=; b=ggQjVqK1yHtGn/KQQBkwP1cMdQ3Flj0A5u8VB4SNd7GhYuFxgVfTrE2g BhnfhykLvconSRcLFQvXatzeqMjDFmwsHcC6/EFxdUSWs8JoYWScHGSvi nPQctJ+Rgma2RFb8sbrwGLfTBLJnkn3AVl3PtoITTF3glX5ybsJ9Ie4gR vawK5AS8UCVrDmAFF+dry1WQ8uKlWQV/D8byKQYZ3yyhk6CEMV5oghzbc 29GEBW8SkZyL6Ju6E8bP1LfctTxEl1gSHQL0NE4dgxOjHy0jSrGrX4dU6 vY0WSFGf6FZsd6h1WQD6xgMJuxQSmaz5uwMC8STsW2eb3SHK1vl7QUm4v g==; X-CSE-ConnectionGUID: 5iISHC6gQPSLg8kzFhaWSg== X-CSE-MsgGUID: abys9xldQvGh0tvKPLh30w== X-IronPort-AV: E=McAfee;i="6800,10657,11647"; a="71759507" X-IronPort-AV: E=Sophos;i="6.21,161,1763452800"; d="scan'208";a="71759507" Received: from orviesa010.jf.intel.com ([10.64.159.150]) by orvoesa107.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Dec 2025 09:26:36 -0800 X-CSE-ConnectionGUID: yeSOH31WQQK+JnuaGnNWLg== X-CSE-MsgGUID: 4IzbiRloTQy2gdnJVym+gw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.21,161,1763452800"; d="scan'208";a="198170501" Received: from silpixa00401385.ir.intel.com ([10.20.224.226]) by orviesa010.jf.intel.com with ESMTP; 19 Dec 2025 09:26:34 -0800 From: Bruce Richardson To: dev@dpdk.org Cc: Bruce Richardson Subject: [RFC PATCH 20/27] net/intel: write descriptors using non-volatile pointers Date: Fri, 19 Dec 2025 17:25:37 +0000 Message-ID: <20251219172548.2660777-21-bruce.richardson@intel.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251219172548.2660777-1-bruce.richardson@intel.com> References: <20251219172548.2660777-1-bruce.richardson@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Use a non-volatile uint64_t pointer to store to the descriptor ring. This will allow the compiler to optionally merge the stores as it sees best. Signed-off-by: Bruce Richardson --- drivers/net/intel/common/tx_scalar_fns.h | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) diff --git a/drivers/net/intel/common/tx_scalar_fns.h b/drivers/net/intel/common/tx_scalar_fns.h index 7b643fcf44..95e9acbe60 100644 --- a/drivers/net/intel/common/tx_scalar_fns.h +++ b/drivers/net/intel/common/tx_scalar_fns.h @@ -184,6 +184,15 @@ struct ci_timesstamp_queue_fns { write_ts_tail_t write_ts_tail; }; +static inline void +write_txd(volatile void *txd, uint64_t qw0, uint64_t qw1) +{ + uint64_t *txd_qw = RTE_CAST_PTR(void *, txd); + + txd_qw[0] = rte_cpu_to_le_64(qw0); + txd_qw[1] = rte_cpu_to_le_64(qw1); +} + static inline uint16_t ci_xmit_pkts(struct ci_tx_queue *txq, struct rte_mbuf **tx_pkts, @@ -313,8 +322,7 @@ ci_xmit_pkts(struct ci_tx_queue *txq, txe->mbuf = NULL; } - ctx_txd[0] = cd_qw0; - ctx_txd[1] = cd_qw1; + write_txd(ctx_txd, cd_qw0, cd_qw1); txe->last_id = tx_last; tx_id = txe->next_id; @@ -361,12 +369,12 @@ ci_xmit_pkts(struct ci_tx_queue *txq, while ((ol_flags & (RTE_MBUF_F_TX_TCP_SEG | RTE_MBUF_F_TX_UDP_SEG)) && unlikely(slen > CI_MAX_DATA_PER_TXD)) { - txd->buffer_addr = rte_cpu_to_le_64(buf_dma_addr); - txd->cmd_type_offset_bsz = rte_cpu_to_le_64(CI_TX_DESC_DTYPE_DATA | + const uint64_t cmd_type_offset_bsz = CI_TX_DESC_DTYPE_DATA | ((uint64_t)td_cmd << CI_TXD_QW1_CMD_S) | ((uint64_t)td_offset << CI_TXD_QW1_OFFSET_S) | ((uint64_t)CI_MAX_DATA_PER_TXD << CI_TXD_QW1_TX_BUF_SZ_S) | - ((uint64_t)td_tag << CI_TXD_QW1_L2TAG1_S)); + ((uint64_t)td_tag << CI_TXD_QW1_L2TAG1_S); + write_txd(txd, buf_dma_addr, cmd_type_offset_bsz); buf_dma_addr += CI_MAX_DATA_PER_TXD; slen -= CI_MAX_DATA_PER_TXD; @@ -382,12 +390,12 @@ ci_xmit_pkts(struct ci_tx_queue *txq, if (m_seg->next == NULL) td_cmd |= CI_TX_DESC_CMD_EOP; - txd->buffer_addr = rte_cpu_to_le_64(buf_dma_addr); - txd->cmd_type_offset_bsz = rte_cpu_to_le_64(CI_TX_DESC_DTYPE_DATA | + const uint64_t cmd_type_offset_bsz = CI_TX_DESC_DTYPE_DATA | ((uint64_t)td_cmd << CI_TXD_QW1_CMD_S) | ((uint64_t)td_offset << CI_TXD_QW1_OFFSET_S) | ((uint64_t)slen << CI_TXD_QW1_TX_BUF_SZ_S) | - ((uint64_t)td_tag << CI_TXD_QW1_L2TAG1_S)); + ((uint64_t)td_tag << CI_TXD_QW1_L2TAG1_S); + write_txd(txd, buf_dma_addr, cmd_type_offset_bsz); txe->last_id = tx_last; tx_id = txe->next_id; -- 2.51.0