From patchwork Wed Jun 19 13:28:27 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Anand Khoje X-Patchwork-Id: 13703829 Received: from mx0a-00069f02.pphosted.com (mx0a-00069f02.pphosted.com [205.220.165.32]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 24F45146016; Wed, 19 Jun 2024 13:28:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.165.32 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718803729; cv=none; b=SX8ufe3bZN8cE8LGkO2jDNoo1HnnBBcR5gV2L5jVZoeJv46HPopZfqybqRoMujF5nZSzxAhwSmKmxloxZA84a9e7cxHskeJh7DXqmVO2YAeLBRnL/bLTEjZaHx5j9EV90lOMr/Nu2DM0GKktfswhPCPPK+qFqSI36WvwOQVLLlc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718803729; c=relaxed/simple; bh=IbU9H+DWKuJetppSWilqM1RixdWQASTCpKWygS68koc=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=gl8VyiaViVhDQ0Pbq0/7AbQPAl1vdYz6jAAdjwjcHbTLXy1GxNm/61fg8iTAIUtpsjp7CBrT2b7a1dXHjgEwi96hh+RxgKILqZtn5S6/9N61YzpEzjzerTsnUfTvM/BQULz2Vl5g7LxxLU1wGzDSKwWApZJlGBi7LGKw2WZmMpE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oracle.com; spf=pass smtp.mailfrom=oracle.com; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b=n6rxkgXi; arc=none smtp.client-ip=205.220.165.32 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oracle.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=oracle.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="n6rxkgXi" Received: from pps.filterd (m0246627.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 45J1tRoI009538; Wed, 19 Jun 2024 13:28:35 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h= from:to:cc:subject:date:message-id:mime-version:content-type :content-transfer-encoding; s=corp-2023-11-20; bh=XqDJjEiAlVyJHw kCLkG1pOnpC+qIkFOEq7vg5dbf2KI=; b=n6rxkgXipv/rLIUTrS8e7bxvz+rc51 rIUx/H0BEsaMOGOtFI3AtT77IC4h2lsf8xOf75Kk4AMvB+pZJy2wbWTa8P60Gm9e Stu1m6PVndUSLvqeVsMsMOrZJDmWM2I+gKbo3cTSGix2C9HCAiCAmRsKcfGfOTDY QrgAf4Y8RCilShs02Y9ul70/h4bVFoyElTjb+hLwIxnDTDgcUrWfwqgBVqIe6vI1 QgHI4vieJ3M0UOcyTw33ToucxAQleTb5V6Z8/LgqLZGPtK5e/veVHlSKyhhLlMPq mP68KNYYuKhc/aDLqJktPIEju18vlKcIJ6yRh9GD60bbtQILChWwgaCA== Received: from phxpaimrmta02.imrmtpd1.prodappphxaev1.oraclevcn.com (phxpaimrmta02.appoci.oracle.com [147.154.114.232]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 3yuja0h8ux-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 19 Jun 2024 13:28:35 +0000 (GMT) Received: from pps.filterd (phxpaimrmta02.imrmtpd1.prodappphxaev1.oraclevcn.com [127.0.0.1]) by phxpaimrmta02.imrmtpd1.prodappphxaev1.oraclevcn.com (8.17.1.19/8.17.1.19) with ESMTP id 45JCPXv7034789; Wed, 19 Jun 2024 13:28:35 GMT Received: from aakhoje-ol.in.oracle.com (dhcp-10-191-198-68.vpn.oracle.com [10.191.198.68]) by phxpaimrmta02.imrmtpd1.prodappphxaev1.oraclevcn.com (PPS) with ESMTP id 3ys1d9jejw-1; Wed, 19 Jun 2024 13:28:34 +0000 From: Anand Khoje To: linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org Cc: saeedm@mellanox.com, leon@kernel.org, tariqt@nvidia.com, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, davem@davemloft.net Subject: [PATCH v4] net/mlx5: Reclaim max 50K pages at once Date: Wed, 19 Jun 2024 18:58:27 +0530 Message-ID: <20240619132827.51306-1-anand.a.khoje@oracle.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-rdma@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1039,Hydra:6.0.680,FMLib:17.12.28.16 definitions=2024-06-19_02,2024-06-19_01,2024-05-17_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxlogscore=999 suspectscore=0 malwarescore=0 phishscore=0 spamscore=0 mlxscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2405010000 definitions=main-2406190101 X-Proofpoint-ORIG-GUID: 5eObyzq1y0ZJDWpVf6dAqeL73j464ly0 X-Proofpoint-GUID: 5eObyzq1y0ZJDWpVf6dAqeL73j464ly0 In non FLR context, at times CX-5 requests release of ~8 million FW pages. This needs humongous number of cmd mailboxes, which to be released once the pages are reclaimed. Release of humongous number of cmd mailboxes is consuming cpu time running into many seconds. Which with non preemptible kernels is leading to critical process starving on that cpu’s RQ. To alleviate this, this change restricts the total number of pages a worker will try to reclaim maximum 50K pages in one go. The limit 50K is aligned with the current firmware capacity/limit of releasing 50K pages at once per MLX5_CMD_OP_MANAGE_PAGES + MLX5_PAGES_TAKE device command. Our tests have shown significant benefit of this change in terms of time consumed by dma_pool_free(). During a test where an event was raised by HCA to release 1.3 Million pages, following observations were made: - Without this change: Number of mailbox messages allocated was around 20K, to accommodate the DMA addresses of 1.3 million pages. The average time spent by dma_pool_free() to free the DMA pool is between 16 usec to 32 usec. value ------------- Distribution ------------- count 256 | 0 512 |@ 287 1024 |@@@ 1332 2048 |@ 656 4096 |@@@@@ 2599 8192 |@@@@@@@@@@ 4755 16384 |@@@@@@@@@@@@@@@ 7545 32768 |@@@@@ 2501 65536 | 0 - With this change: Number of mailbox messages allocated was around 800; this was to accommodate DMA addresses of only 50K pages. The average time spent by dma_pool_free() to free the DMA pool in this case lies between 1 usec to 2 usec. value ------------- Distribution ------------- count 256 | 0 512 |@@@@@@@@@@@@@@@@@@ 346 1024 |@@@@@@@@@@@@@@@@@@@@@@ 435 2048 | 0 4096 | 0 8192 | 1 16384 | 0 Signed-off-by: Anand Khoje Reviewed-by: Leon Romanovsky --- Changes in v4: - Fixed a nit in patch subject. --- drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c b/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c index dcf58ef..06eee3a 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c @@ -608,6 +608,7 @@ enum { RELEASE_ALL_PAGES_MASK = 0x4000, }; +#define MAX_RECLAIM_NPAGES -50000 static int req_pages_handler(struct notifier_block *nb, unsigned long type, void *data) { @@ -639,9 +640,13 @@ static int req_pages_handler(struct notifier_block *nb, req->dev = dev; req->func_id = func_id; - req->npages = npages; req->ec_function = ec_function; req->release_all = release_all; + if (npages < MAX_RECLAIM_NPAGES) + req->npages = MAX_RECLAIM_NPAGES; + else + req->npages = npages; + INIT_WORK(&req->work, pages_work_handler); queue_work(dev->priv.pg_wq, &req->work); return NOTIFY_OK;