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=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS 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 399BEC433DF for ; Tue, 23 Jun 2020 18:15:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 12D09207FF for ; Tue, 23 Jun 2020 18:15:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592936111; bh=EakZHm4+pAlaLBl8b0/zepdJSj8NnqMpyqyLuGP155k=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=MSv6KrS8t4aDIC2Cofc21ZOG4OBnLBZ0TeezLXM4hO6MhdMQEAzoILMXKoF0ih8CB KrCpoSLzBQpXzglLSWQQoxBgTFyuggTNfJBXdYNa9n9ea1IxUslSGkKKYFq04XK6N4 gpPoH2poRrxIg1kyombjBsBBhPaHDF6+abu5VbzU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732988AbgFWSPK (ORCPT ); Tue, 23 Jun 2020 14:15:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:53898 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728916AbgFWSPK (ORCPT ); Tue, 23 Jun 2020 14:15:10 -0400 Received: from localhost (unknown [213.57.247.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 264E1207FB; Tue, 23 Jun 2020 18:15:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592936109; bh=EakZHm4+pAlaLBl8b0/zepdJSj8NnqMpyqyLuGP155k=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=gnBd7FAzBXDE0WYAhX1XelWRjJDw0V2xDflB9FIUgbu12XlM60+vlpDJf/gOTx0HY dku8VqXWwbYi3B4prtgbnQ3glFxjdbx1KwmfiugBaJBirHigDgJf4AV7znNThfUgZb tutVcbFD/Mx18Xg9HubA3moKxb5G9ErXOQYjsTNk= Date: Tue, 23 Jun 2020 21:15:06 +0300 From: Leon Romanovsky To: Jason Gunthorpe Cc: Doug Ledford , Maor Gottlieb , linux-rdma@vger.kernel.org Subject: Re: [PATCH rdma-next v1 2/2] RDMA/core: Optimize XRC target lookup Message-ID: <20200623181506.GC184720@unreal> References: <20200623111531.1227013-1-leon@kernel.org> <20200623111531.1227013-3-leon@kernel.org> <20200623175200.GA3096958@mellanox.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200623175200.GA3096958@mellanox.com> Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Tue, Jun 23, 2020 at 02:52:00PM -0300, Jason Gunthorpe wrote: > On Tue, Jun 23, 2020 at 02:15:31PM +0300, Leon Romanovsky wrote: > > From: Maor Gottlieb > > > > Replace the mutex with read write semaphore and use xarray instead > > of linked list for XRC target QPs. This will give faster XRC target > > lookup. In addition, when QP is closed, don't insert it back to the > > xarray if the destroy command failed. > > > > Signed-off-by: Maor Gottlieb > > Signed-off-by: Leon Romanovsky > > drivers/infiniband/core/verbs.c | 57 ++++++++++++--------------------- > > include/rdma/ib_verbs.h | 5 ++- > > 2 files changed, 23 insertions(+), 39 deletions(-) > > > > diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c > > index d66a0ad62077..1ccbe43e33cd 100644 > > +++ b/drivers/infiniband/core/verbs.c > > @@ -1090,13 +1090,6 @@ static void __ib_shared_qp_event_handler(struct ib_event *event, void *context) > > spin_unlock_irqrestore(&qp->device->qp_open_list_lock, flags); > > } > > > > -static void __ib_insert_xrcd_qp(struct ib_xrcd *xrcd, struct ib_qp *qp) > > -{ > > - mutex_lock(&xrcd->tgt_qp_mutex); > > - list_add(&qp->xrcd_list, &xrcd->tgt_qp_list); > > - mutex_unlock(&xrcd->tgt_qp_mutex); > > -} > > - > > static struct ib_qp *__ib_open_qp(struct ib_qp *real_qp, > > void (*event_handler)(struct ib_event *, void *), > > void *qp_context) > > @@ -1139,16 +1132,15 @@ struct ib_qp *ib_open_qp(struct ib_xrcd *xrcd, > > if (qp_open_attr->qp_type != IB_QPT_XRC_TGT) > > return ERR_PTR(-EINVAL); > > > > - qp = ERR_PTR(-EINVAL); > > - mutex_lock(&xrcd->tgt_qp_mutex); > > - list_for_each_entry(real_qp, &xrcd->tgt_qp_list, xrcd_list) { > > - if (real_qp->qp_num == qp_open_attr->qp_num) { > > - qp = __ib_open_qp(real_qp, qp_open_attr->event_handler, > > - qp_open_attr->qp_context); > > - break; > > - } > > + down_read(&xrcd->tgt_qps_rwsem); > > + real_qp = xa_load(&xrcd->tgt_qps, qp_open_attr->qp_num); > > + if (!real_qp) { > > Don't we already have a xarray indexed against qp_num in res_track? > Can we use it somehow? We don't have restrack for XRC, we will need somehow manage QP-to-XRC connection there. Thanks > > Jason