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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 73367C4332F for ; Thu, 3 Nov 2022 06:56:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229709AbiKCG4M (ORCPT ); Thu, 3 Nov 2022 02:56:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36308 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229745AbiKCG4J (ORCPT ); Thu, 3 Nov 2022 02:56:09 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DA47625C0 for ; Wed, 2 Nov 2022 23:56:08 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 87859B82675 for ; Thu, 3 Nov 2022 06:56:07 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 22286C433C1; Thu, 3 Nov 2022 06:56:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1667458566; bh=yCIqxIoXfc5kamIuxwM4Y1tlh9EQbVTy+Nv9vethuz4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ECSIb/M82O5EGvHwbj0T+hpJJD7sjnoHg6/Tz2mpLFO57P/7HLtp2hvCHl8/HCw8Y kbVYPqVnRAzbwmkPr5LopBm03Z5Si4GNpj4cqwsitrqBjRYeTOlEFi1MvYdULYzvRX SwRTLXAMhCD2ypfFXQh/g219ufGA7W/l3VIjqhtStQ4vslPjDeu0TLT/9Rb8cAiwjG vS2Hxyvipy3b3J7xkioxPC/FlILY5Xsli6+Mm7Qk6X3MjyJKTZlLW8dkt2C9dwnf+7 jOLCuffCjLxImyTv51RdvtEtz0R8lKwOhIDgbpxidzvRdRQdq3RMAVOFUdrPub5R2m EbjvN4X2+FMPA== From: Saeed Mahameed To: "David S. Miller" , Jakub Kicinski , Paolo Abeni , Eric Dumazet Cc: Saeed Mahameed , netdev@vger.kernel.org, Tariq Toukan , Roy Novich , Alexander Schmidt , Moshe Shemesh Subject: [net 02/11] net/mlx5: Allow async trigger completion execution on single CPU systems Date: Wed, 2 Nov 2022 23:55:38 -0700 Message-Id: <20221103065547.181550-3-saeed@kernel.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221103065547.181550-1-saeed@kernel.org> References: <20221103065547.181550-1-saeed@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Roy Novich For a single CPU system, the kernel thread executing mlx5_cmd_flush() never releases the CPU but calls down_trylock(&cmd→sem) in a busy loop. On a single processor system, this leads to a deadlock as the kernel thread which executes mlx5_cmd_invoke() never gets scheduled. Fix this, by adding the cond_resched() call to the loop, allow the command completion kernel thread to execute. Fixes: 8e715cd613a1 ("net/mlx5: Set command entry semaphore up once got index free") Signed-off-by: Alexander Schmidt Signed-off-by: Roy Novich Reviewed-by: Moshe Shemesh Signed-off-by: Saeed Mahameed --- drivers/net/ethernet/mellanox/mlx5/core/cmd.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c index 46ba4c2faad2..2e0d59ca62b5 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c @@ -1770,12 +1770,17 @@ void mlx5_cmd_flush(struct mlx5_core_dev *dev) struct mlx5_cmd *cmd = &dev->cmd; int i; - for (i = 0; i < cmd->max_reg_cmds; i++) - while (down_trylock(&cmd->sem)) + for (i = 0; i < cmd->max_reg_cmds; i++) { + while (down_trylock(&cmd->sem)) { mlx5_cmd_trigger_completions(dev); + cond_resched(); + } + } - while (down_trylock(&cmd->pages_sem)) + while (down_trylock(&cmd->pages_sem)) { mlx5_cmd_trigger_completions(dev); + cond_resched(); + } /* Unlock cmdif */ up(&cmd->pages_sem); -- 2.38.1