linux-kernel - Re: [PATCH rdma-next] RDMA/rdmavt: Decouple QP and SGE lists allocations

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <YJp589JwbqGvljew@unreal>
Date:   Tue, 11 May 2021 15:34:59 +0300
From:   Leon Romanovsky <leon@...nel.org>
To:     Dennis Dalessandro <dennis.dalessandro@...nelisnetworks.com>
Cc:     Doug Ledford <dledford@...hat.com>,
        Jason Gunthorpe <jgg@...dia.com>, linux-kernel@...r.kernel.org,
        linux-rdma@...r.kernel.org,
        Mike Marciniszyn <mike.marciniszyn@...nelisnetworks.com>
Subject: Re: [PATCH rdma-next] RDMA/rdmavt: Decouple QP and SGE lists
 allocations

On Tue, May 11, 2021 at 08:26:43AM -0400, Dennis Dalessandro wrote:
> On 5/11/21 6:36 AM, Leon Romanovsky wrote:
> > From: Leon Romanovsky <leonro@...dia.com>
> > 
> > The rdmavt QP has fields that are both needed for the control and data
> > path. Such mixed declaration caused to the very specific allocation flow
> > with kzalloc_node and SGE list embedded into the struct rvt_qp.
> > 
> > This patch separates QP creation to two: regular memory allocation for
> > the control path and specific code for the SGE list, while the access to
> > the later is performed through derefenced pointer.
> > 
> > Such pointer and its context are expected to be in the cache, so
> > performance difference is expected to be negligible, if any exists.
> > 
> > Signed-off-by: Leon Romanovsky <leonro@...dia.com>
> > ---
> > Hi,
> > 
> > This change is needed to convert QP to core allocation scheme. In that
> > scheme QP is allocated outside of the driver and size of such allocation
> > is constant and can be calculated at the compile time.
> 
> Thanks Leon, we'll get this put through our testing.

Thanks a lot.

> 
> -Denny