From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-14.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4CE86C433ED for ; Thu, 22 Apr 2021 09:45:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0EB26600EF for ; Thu, 22 Apr 2021 09:45:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235755AbhDVJp5 (ORCPT ); Thu, 22 Apr 2021 05:45:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58530 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235339AbhDVJp4 (ORCPT ); Thu, 22 Apr 2021 05:45:56 -0400 Received: from mail-ed1-x52a.google.com (mail-ed1-x52a.google.com [IPv6:2a00:1450:4864:20::52a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0BE52C06174A for ; Thu, 22 Apr 2021 02:45:22 -0700 (PDT) Received: by mail-ed1-x52a.google.com with SMTP id s15so52683043edd.4 for ; Thu, 22 Apr 2021 02:45:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-language:content-transfer-encoding; bh=InL6JkjcoekxNOoclWCb17Bs9BWbgksVUpeKoXAFNFE=; b=J7mMK5yAhWb0ur7UgcTIW/757x26JAj//w2lEOlF1s6bCNRqOfyRCrqK3eC1DiXKiD qROQcZyL5AjPBHDYqumfURnH/i19AtWJJmmpARTLxYcZLZ8WSKh1CZqfJAeEvN+pWl0v 7jeiqZOApKC83/CXEj/Edk0Mpx3wn2utkm+TUxiEUSS10xL8Mh2JFcYBepBRDmOQU/Mi /73KdlO7DV63y0oHmhDLCG3eZA+M1l5FGiU90zkj3mbA+LJVuPsAunsAu7l8uyQzn5Ja Lbuh4wRW9uyPrRhzc7vWmgI7ejLhYq47NoYdgwfWMLxQDzyr3JfiPULA+sjh7bfWIjwD 2YVA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=InL6JkjcoekxNOoclWCb17Bs9BWbgksVUpeKoXAFNFE=; b=CZRptVm2kmslgqXLH8LVyk+PlYzePj8sPHJvh9g20HPzQAEoBfRqz6yrs2xTYOrxxQ l65It5WYDgEk+ixHsD/qr1elSh2BnVXXLWNFc/HK36/XxpGHilqXh81wp94pqpoD5d3l nM0zTO2QH92cD5T0FqKCtD4Yrm8DlDduFyfST2WtLzc/cez1ixbrFNQLFQyjs55vjfhn M1S2Cl+ubNyHkBa7G/2x2FPGy2I7bnoGT/1Rjwuvos8pKwRxyUXnTTAURHwpZ7q/lVW/ i1b7G27Y2o5Fj9YAHCqy5uyQuBitYD3siHNN+n1Y1NrGqhG5IJHWmf6AOMgndXvzkfHn ouLQ== X-Gm-Message-State: AOAM531/GbcqCmtmZIzKDAPxvSzgKRxeXry60sGpxqh2edXSUDnclCbA tbwSxWhVJk8tGsPMlubJ1QE8r0+kiOY= X-Google-Smtp-Source: ABdhPJzzsq8kjDxeOQloJcxiCuybvJIgpWuFsy3DucjgYkMH3WbYTUVWjHLhl5Vn6RrFNgLHTWyJCQ== X-Received: by 2002:a05:6402:2219:: with SMTP id cq25mr2680989edb.60.1619084720619; Thu, 22 Apr 2021 02:45:20 -0700 (PDT) Received: from [192.168.1.115] ([77.124.203.106]) by smtp.gmail.com with ESMTPSA id w6sm1473542eje.107.2021.04.22.02.45.19 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 22 Apr 2021 02:45:20 -0700 (PDT) Subject: Re: [PATCH v2 net-next] net/mlx4: Treat VFs fair when handling comm_channel_events To: Hans Westgaard Ry , Tariq Toukan , "David S. Miller" , Jakub Kicinski , netdev@vger.kernel.org References: <1619072500-13789-1-git-send-email-hans.westgaard.ry@oracle.com> From: Tariq Toukan Message-ID: Date: Thu, 22 Apr 2021 12:45:18 +0300 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.9.1 MIME-Version: 1.0 In-Reply-To: <1619072500-13789-1-git-send-email-hans.westgaard.ry@oracle.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 4/22/2021 9:21 AM, Hans Westgaard Ry wrote: > Handling comm_channel_event in mlx4_master_comm_channel uses a double > loop to determine which slaves have requested work. The search is > always started at lowest slave. This leads to unfairness; lower VFs > tends to be prioritized over higher VFs. > > The patch uses find_next_bit to determine which slaves to handle. > Fairness is implemented by always starting at the next to the last > start. > > An MPI program has been used to measure improvements. It runs 500 > ibv_reg_mr, synchronizes with all other instances and then runs 500 > ibv_dereg_mr. > > The results running 500 processes, time reported is for running 500 > calls: > > ibv_reg_mr: > Mod. Org. > mlx4_1 403.356ms 424.674ms > mlx4_2 403.355ms 424.674ms > mlx4_3 403.354ms 424.674ms > mlx4_4 403.355ms 424.674ms > mlx4_5 403.357ms 424.677ms > mlx4_6 403.354ms 424.676ms > mlx4_7 403.357ms 424.675ms > mlx4_8 403.355ms 424.675ms > > ibv_dereg_mr: > Mod. Org. > mlx4_1 116.408ms 142.818ms > mlx4_2 116.434ms 142.793ms > mlx4_3 116.488ms 143.247ms > mlx4_4 116.679ms 143.230ms > mlx4_5 112.017ms 107.204ms > mlx4_6 112.032ms 107.516ms > mlx4_7 112.083ms 184.195ms > mlx4_8 115.089ms 190.618ms > > Suggested-by: Håkon Bugge > Signed-off-by: Hans Westgaard Ry > --- > v1 -> v2: > - removed set but not user varible, > reported by 'kernel test robot' > - fixed reversed Christmas tree, > removed else, > removed extra varibles in printout, > moved next_slave to struct mlx4_mfunc_master_ctx, > as suggested by Tariq Toukan > drivers/net/ethernet/mellanox/mlx4/cmd.c | 69 ++++++++++++++++++------------- > drivers/net/ethernet/mellanox/mlx4/mlx4.h | 1 + > 2 files changed, 41 insertions(+), 29 deletions(-) > > diff --git a/drivers/net/ethernet/mellanox/mlx4/cmd.c b/drivers/net/ethernet/mellanox/mlx4/cmd.c > index c678344d22a2..8d751383530b 100644 > --- a/drivers/net/ethernet/mellanox/mlx4/cmd.c > +++ b/drivers/net/ethernet/mellanox/mlx4/cmd.c > @@ -2241,43 +2241,52 @@ void mlx4_master_comm_channel(struct work_struct *work) > struct mlx4_priv *priv = > container_of(mfunc, struct mlx4_priv, mfunc); > struct mlx4_dev *dev = &priv->dev; > - __be32 *bit_vec; > + u32 lbit_vec[COMM_CHANNEL_BIT_ARRAY_SIZE]; > + u32 nmbr_bits; > u32 comm_cmd; > - u32 vec; > - int i, j, slave; > + int i, slave; > int toggle; > + bool first = true; > int served = 0; > int reported = 0; > u32 slt; > > - bit_vec = master->comm_arm_bit_vector; > - for (i = 0; i < COMM_CHANNEL_BIT_ARRAY_SIZE; i++) { > - vec = be32_to_cpu(bit_vec[i]); > - for (j = 0; j < 32; j++) { > - if (!(vec & (1 << j))) > - continue; > - ++reported; > - slave = (i * 32) + j; > - comm_cmd = swab32(readl( > - &mfunc->comm[slave].slave_write)); > - slt = swab32(readl(&mfunc->comm[slave].slave_read)) > - >> 31; > - toggle = comm_cmd >> 31; > - if (toggle != slt) { > - if (master->slave_state[slave].comm_toggle > - != slt) { > - pr_info("slave %d out of sync. read toggle %d, state toggle %d. Resynching.\n", > - slave, slt, > - master->slave_state[slave].comm_toggle); > - master->slave_state[slave].comm_toggle = > - slt; > - } > - mlx4_master_do_cmd(dev, slave, > - comm_cmd >> 16 & 0xff, > - comm_cmd & 0xffff, toggle); > - ++served; > + for (i = 0; i < COMM_CHANNEL_BIT_ARRAY_SIZE; i++) > + lbit_vec[i] = be32_to_cpu(master->comm_arm_bit_vector[i]); > + nmbr_bits = dev->persist->num_vfs + 1; > + if (++master->next_slave >= nmbr_bits) > + master->next_slave = 0; > + slave = master->next_slave; > + while (true) { > + slave = find_next_bit((const unsigned long *)&lbit_vec, nmbr_bits, slave); > + if (!first && slave >= master->next_slave) > + break; > + if (slave == nmbr_bits) { > + if (!first) > + break; > + first = false; > + slave = 0; > + continue; > + } > + ++reported; > + comm_cmd = swab32(readl(&mfunc->comm[slave].slave_write)); > + slt = swab32(readl(&mfunc->comm[slave].slave_read)) >> 31; > + toggle = comm_cmd >> 31; > + if (toggle != slt) { > + if (master->slave_state[slave].comm_toggle > + != slt) { > + pr_info("slave %d out of sync. read toggle %d, state toggle %d. Resynching.\n", > + slave, slt, > + master->slave_state[slave].comm_toggle); > + master->slave_state[slave].comm_toggle = > + slt; > } > + mlx4_master_do_cmd(dev, slave, > + comm_cmd >> 16 & 0xff, > + comm_cmd & 0xffff, toggle); > + ++served; > } > + slave++; > } > > if (reported && reported != served) > @@ -2389,6 +2398,8 @@ int mlx4_multi_func_init(struct mlx4_dev *dev) > if (!priv->mfunc.master.vf_oper) > goto err_comm_oper; > > + priv->mfunc.master.next_slave = 0; > + > for (i = 0; i < dev->num_slaves; ++i) { > vf_admin = &priv->mfunc.master.vf_admin[i]; > vf_oper = &priv->mfunc.master.vf_oper[i]; > diff --git a/drivers/net/ethernet/mellanox/mlx4/mlx4.h b/drivers/net/ethernet/mellanox/mlx4/mlx4.h > index 64bed7ac3836..6ccf340660d9 100644 > --- a/drivers/net/ethernet/mellanox/mlx4/mlx4.h > +++ b/drivers/net/ethernet/mellanox/mlx4/mlx4.h > @@ -603,6 +603,7 @@ struct mlx4_mfunc_master_ctx { > struct mlx4_slave_event_eq slave_eq; > struct mutex gen_eqe_mutex[MLX4_MFUNC_MAX]; > struct mlx4_qos_manager qos_ctl[MLX4_MAX_PORTS + 1]; > + u32 next_slave; /* mlx4_master_comm_channel */ > }; > > struct mlx4_mfunc { > Reviewed-by: Tariq Toukan Thanks, Tariq