[ofw] [PATCH 0/9] merging winverbs into trunk

[Sean Hefty]

Winverbs is a userspace verbs interface designed for Windows.  It provides an
asynchronous COM like interface that allows use of common Windows programming
constructs, such as overlapped I/O and I/O completion ports, and it allows the
application to control all threading.

Winverbs consists of:

	* Userspace library (dll)
	* Kernel upper filter driver for Infiniband/RDMA controllers

and requires:

	* User-verbs provider library
	* Kernel Infiniband/RDMA controller driver

Winverbs is designed to integrate with the existing Windows stack with minimal
changes.  This patch series contains those changes.

In addition to this patch set, the following new components are added:

	* Winverbs library
		- Support for 'verbs' related calls only, no connections
	* Winverbs filter driver
	* libibverbs port to Windows, including
		- RC, UC, and UD pingpong
		- ibv_devinfo
	* perftest port to Windows:
		- ibv_read_bw, ibv_read_lat
		- ibv_write_bw, ibv_write_lat
		- ibv_send_bw, ibv_send_lat

Patch sets for new components will be submitted separately.

The following lists the performance delta running perftests over ibal versus
perftests running over libibverbs over winverbs.  The values are % improvement
using winverbs versus ibal, and show that there's basically no performance
difference for these tests.  (All differences are within the noise levels on my
systems.)

		x86	x64
send	lat	2.0%	-0.2%
	bw	0.2%	0.0%
write	lat	1.6%	1.3%
	bw	0.7%	0.0%
read	lat	0.2%	0.1%
	bw	0.2%	0.0%

Winverbs exposes interfaces that map well for supporting network direct, but
exposes additional functionality not exposed by network direct, but needed by
other MPI and RDMA applications.  It supports libibverbs, and more closely
mimics the libibverbs event processing model than a threading callback model
would.  It will eventually export RDMA CM interfaces, along with a port of
librdmacm.  (The winverbs RDMA CM interfaces are defined, but not implemented.)

Signed-off-by: Sean Hefty <sean.hefty at intel.com>