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=-16.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 0D621C48BCD for ; Mon, 7 Jun 2021 11:00:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E8D24610A2 for ; Mon, 7 Jun 2021 11:00:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231140AbhFGLCV (ORCPT ); Mon, 7 Jun 2021 07:02:21 -0400 Received: from mail.kernel.org ([198.145.29.99]:48988 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230390AbhFGLCU (ORCPT ); Mon, 7 Jun 2021 07:02:20 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 25AAB60FDA; Mon, 7 Jun 2021 11:00:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1623063629; bh=6bMsVqbjM3++t48Qy6Kp7HdeCZdhuDq84Ibcb57h3cc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=UeoyKq7nK1d24iFE9saVFY/HYwebI1+iEUwBoEHw6MYPdCPdV3i6cyRJEtSPG0N40 tNN+rWvYgDtV1Brk/6ZbVvUJp2ce7xxARktYxSaq4IFv7ST4VxuWUlGAMCvCUcJsCy 8N/foYQ+CQpwPBSQYjDcuE4Vn3NZwrMBVVsoY6kxDq+kqQwCK+DnKyg268+w7sGojd DkikBp2TjdE0SSuLKd3oUt2D5sEVer899LH6wNdJ/jFykwoU/Ehh6ekbujtOKHQJWw HYilPjP6jFSw3hM98+3yDGv5H216YLaIqNp5u/JubhD59YcOHG9Rgvy6pApjmMOJqA A+UmnH8JSu7Og== Date: Mon, 7 Jun 2021 14:00:26 +0300 From: Leon Romanovsky To: Greg KH Cc: Doug Ledford , Jason Gunthorpe , Kees Cook , Nathan Chancellor , Adit Ranadive , Ariel Elior , Christian Benvenuti , clang-built-linux@googlegroups.com, Dennis Dalessandro , Devesh Sharma , Gal Pressman , linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org, Michal Kalderon , Mike Marciniszyn , Mustafa Ismail , Naresh Kumar PBS , Nelson Escobar , Nick Desaulniers , Potnuri Bharat Teja , Selvin Xavier , Shiraz Saleem , VMware PV-Drivers , Yishai Hadas , Zhu Yanjun Subject: Re: [PATCH rdma-next v1 02/15] RDMA/core: Replace the ib_port_data hw_stats pointers with a ib_port pointer Message-ID: References: <6477a29059b1b4d92ea003e3b801a8d1df6d516d.1623053078.git.leonro@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Mon, Jun 07, 2021 at 12:23:23PM +0200, Greg KH wrote: > On Mon, Jun 07, 2021 at 11:17:27AM +0300, Leon Romanovsky wrote: > > From: Jason Gunthorpe > > > > It is much saner to store a pointer to the kobject structure that contains > > the cannonical stats pointer than to copy the stats pointers into a public > > structure. > > > > Future patches will require the sysfs pointer for other purposes. > > > > Signed-off-by: Jason Gunthorpe > > Signed-off-by: Leon Romanovsky > > --- > > drivers/infiniband/core/core_priv.h | 1 + > > drivers/infiniband/core/nldev.c | 8 ++------ > > drivers/infiniband/core/sysfs.c | 14 +++++++++++--- > > include/rdma/ib_verbs.h | 3 ++- > > 4 files changed, 16 insertions(+), 10 deletions(-) > > > > diff --git a/drivers/infiniband/core/core_priv.h b/drivers/infiniband/core/core_priv.h > > index 29809dd30041..ec5c2c3db423 100644 > > --- a/drivers/infiniband/core/core_priv.h > > +++ b/drivers/infiniband/core/core_priv.h > > @@ -378,6 +378,7 @@ struct net_device *rdma_read_gid_attr_ndev_rcu(const struct ib_gid_attr *attr); > > > > void ib_free_port_attrs(struct ib_core_device *coredev); > > int ib_setup_port_attrs(struct ib_core_device *coredev); > > +struct rdma_hw_stats *ib_get_hw_stats_port(struct ib_device *ibdev, u32 port_num); > > > > int rdma_compatdev_set(u8 enable); > > > > diff --git a/drivers/infiniband/core/nldev.c b/drivers/infiniband/core/nldev.c > > index 01316926cef6..e9b4b2cccaa0 100644 > > --- a/drivers/infiniband/core/nldev.c > > +++ b/drivers/infiniband/core/nldev.c > > @@ -2066,7 +2066,8 @@ static int stat_get_doit_default_counter(struct sk_buff *skb, > > } > > > > port = nla_get_u32(tb[RDMA_NLDEV_ATTR_PORT_INDEX]); > > - if (!rdma_is_port_valid(device, port)) { > > + stats = ib_get_hw_stats_port(device, port); > > + if (!stats) { > > ret = -EINVAL; > > goto err; > > } > > @@ -2088,11 +2089,6 @@ static int stat_get_doit_default_counter(struct sk_buff *skb, > > goto err_msg; > > } > > > > - stats = device->port_data ? device->port_data[port].hw_stats : NULL; > > - if (stats == NULL) { > > - ret = -EINVAL; > > - goto err_msg; > > - } > > mutex_lock(&stats->lock); > > > > num_cnts = device->ops.get_hw_stats(device, stats, port, 0); > > diff --git a/drivers/infiniband/core/sysfs.c b/drivers/infiniband/core/sysfs.c > > index d11ceff2b4e4..b153dee1e0fa 100644 > > --- a/drivers/infiniband/core/sysfs.c > > +++ b/drivers/infiniband/core/sysfs.c > > @@ -1031,8 +1031,6 @@ static void setup_hw_stats(struct ib_device *device, struct ib_port *port, > > goto err; > > port->hw_stats_ag = hsag; > > port->hw_stats = stats; > > - if (device->port_data) > > - device->port_data[port_num].hw_stats = stats; > > } else { > > struct kobject *kobj = &device->dev.kobj; > > ret = sysfs_create_group(kobj, hsag); > > @@ -1053,6 +1051,14 @@ static void setup_hw_stats(struct ib_device *device, struct ib_port *port, > > kfree(stats); > > } > > > > +struct rdma_hw_stats *ib_get_hw_stats_port(struct ib_device *ibdev, > > + u32 port_num) > > +{ > > + if (!ibdev->port_data || !rdma_is_port_valid(ibdev, port_num)) > > + return NULL; > > + return ibdev->port_data[port_num].sysfs->hw_stats; > > +} > > + > > static int add_port(struct ib_core_device *coredev, int port_num) > > { > > struct ib_device *device = rdma_device_to_ibdev(&coredev->dev); > > @@ -1171,6 +1177,8 @@ static int add_port(struct ib_core_device *coredev, int port_num) > > setup_hw_stats(device, p, port_num); > > > > list_add_tail(&p->kobj.entry, &coredev->port_list); > > + if (device->port_data && is_full_dev) > > + device->port_data[port_num].sysfs = p; > > You are saving off a pointer to a reference counted structure without > incrementing the reference count on it? That's brave, and really wrong. This is done to ensure that device->port_data[port_num].sysfs is not set before "p" is properly configured. From reference point of view "sysfs" is equal to "p" and the latter already initialized. Thanks