RE: [PATCH v10 01/20] dlb: add skeleton for DLB driver

-----Original Message-----
From: gregkh@linuxfoundation.org <gregkh@linuxfoundation.org>
Sent: Thursday, February 18, 2021 2:53 AM
To: Chen, Mike Ximing <redacted>
Cc: netdev@vger.kernel.org; Linux Kernel Mailing List <linux-
kernel@vger.kernel.org>; davem@davemloft.net; kuba@kernel.org; arnd@arndb.de;
Williams, Dan J [off-list ref]; pierre-louis.bossart@linux.intel.com
Subject: Re: [PATCH v10 01/20] dlb: add skeleton for DLB driver

On Thu, Feb 18, 2021 at 07:34:31AM +0000, Chen, Mike Ximing wrote:

quoted

quoted

-----Original Message-----
From: Mike Ximing Chen <redacted>
Sent: Wednesday, February 10, 2021 12:54 PM
To: netdev@vger.kernel.org
Cc: davem@davemloft.net; kuba@kernel.org; arnd@arndb.de;
gregkh@linuxfoundation.org; Williams, Dan J [off-list ref];

pierre-

quoted

quoted

louis.bossart@linux.intel.com; Gage Eads [off-list ref]
Subject: [PATCH v10 01/20] dlb: add skeleton for DLB driver

diff --git a/Documentation/misc-devices/dlb.rst b/Documentation/misc-

devices/dlb.rst
new file mode 100644
index 000000000000..aa79be07ee49

--- /dev/null
+++ b/Documentation/misc-devices/dlb.rst

@@ -0,0 +1,259 @@
+.. SPDX-License-Identifier: GPL-2.0-only
+
+===========================================
+Intel(R) Dynamic Load Balancer Overview
+===========================================
+
+:Authors: Gage Eads and Mike Ximing Chen
+
+Contents
+========
+
+- Introduction
+- Scheduling
+- Queue Entry
+- Port
+- Queue
+- Credits
+- Scheduling Domain
+- Interrupts
+- Power Management
+- User Interface
+- Reset
+
+Introduction
+============
+
+The Intel(r) Dynamic Load Balancer (Intel(r) DLB) is a PCIe device that
+provides load-balanced, prioritized scheduling of core-to-core communication.
+
+Intel DLB is an accelerator for the event-driven programming model of
+DPDK's Event Device Library[2]. The library is used in packet processing
+pipelines that arrange for multi-core scalability, dynamic load-balancing, and
+variety of packet distribution and synchronization schemes.
+
+Intel DLB device consists of queues and arbiters that connect producer
+cores and consumer cores. The device implements load-balanced queueing

features
+including:
+- Lock-free multi-producer/multi-consumer operation.
+- Multiple priority levels for varying traffic types.
+- 'Direct' traffic (i.e. multi-producer/single-consumer)
+- Simple unordered load-balanced distribution.
+- Atomic lock free load balancing across multiple consumers.
+- Queue element reordering feature allowing ordered load-balanced distribution.
+

Hi Jakub/Dave,
This is a device driver for a HW core-to-core communication accelerator. It is

submitted

quoted

to "linux-kernel" for a module under device/misc. Greg suggested (see below) that

we

quoted

also sent it to you for any potential feedback in case there is any interaction with
networking initiatives. The device is used to handle the load balancing among CPU

cores

quoted

after the packets are received and forwarded to CPU. We don't think it interferes
with networking operations, but would appreciate very much your

review/comment on this.

It's the middle of the merge window, getting maintainers to review new
stuff until after 5.12-rc1 is out is going to be a very difficult thing
to do.

Hi Jakub/Dave,
Just wonder if you had a chance to take a look at our patch. With the close of 5.12
merge window, we would like to get the process moving again.

In the meantime, why don't you all help out and review submitted patches
to the mailing lists for the subsystems you all are trying to get this
patch into.  I know maintainers would appreciate the help, right?

thanks,

greg k-h

Did a few reviews last weekend, and will continue to help.

Thanks
Mike