NetBSD

History

pooka d47455e39d Add uniprocessor versions of mutex/rw/cv. They work only on virtual unicpu configurations (i.e. RUMP_NCPU==1), but are massively faster than the multiprocessor versions since the fast path does not have to perform any cache coherent operations. _Applications_ with lock-happy kernel paths, i.e. _not_ lock microbenchmarks, measure up to tens of percents speedup on my Core2 Duo. Every globally atomic state required by normal locks/atomic ops implies a hideous speed penalty even for the fast path. While this requires a unicpu configuration, it should be noted that we are talking about a virtual unicpu configuration. The host can have as many processors as it desires, and the speed benefit of virtual unicpu is still there. It's pretty obvious that in terms of scalability simple workload partitioning and replication into multiple kernels wins hands down over complicated locking or locklessing algorithms which depend on globally atomic state.		2010-05-18 16:29:36 +00:00
..
dev	remember to add audio to the list of device components	2010-05-01 23:24:40 +00:00
fs
include	Make it possible to use the scheduler lock as the rumpuser condvar	2010-05-18 14:58:41 +00:00
librump	Add uniprocessor versions of mutex/rw/cv. They work only on virtual	2010-05-18 16:29:36 +00:00
net	Remove bpf modload code. With the current state of affairs, the	2010-04-30 21:05:52 +00:00
ldscript.rump
Makefile
Makefile.rump	Limit visibility of _RUMPKERNEL to prevent abuse.	2010-05-11 21:08:07 +00:00
README.dirs	update slightly	2010-05-11 11:58:14 +00:00
TODO

README.dirs

	$NetBSD: README.dirs,v 1.11 2010/05/11 11:58:14 pooka Exp $


The following is a quick rundown of the current directory structure.
First, components in the kernel namespace, i.e. compiled with -D_KERNEL

sys/rump/librump - kernel runtime emulation
  /rumpkern	- kernel core, e.g. syscall, interrupt and lock support

  /rumpcrypto	- kernel cryptographic routines
  /rumpdev	- device support, e.g. autoconf subsystem
  /rumpnet	- networking support and sockets layer
  /rumpvfs	- file system support

sys/rump/include
  /machine - used for architectures where the rump ABI is not yet the
	     same as the kernel module ABI.  will eventually disappear
	     completely
  /rump    - rump headers installed to userspace

sys/rump/dev - device components, e.g. audio, raidframe, usb drivers

sys/rump/fs - file system components
  /lib/lib${fs}  - kernel file system code

sys/rump/net - networking components
  /lib/libnet	  - subroutines from sys/net, e.g. route and if_ethersubr
  /lib/libnetinet - TCP/IP
  /lib/libvirtif  - a virtual interface which uses host tap(4) to shovel
		    packets.  This is used by netinet and if_ethersubr.
  /lib/libsockin  - implements PF_INET using host kernel sockets.  This is
		    mutually exclusive with net, netinet and virtif.



The rest are out-of-kernel components (i.e. no -D_KERNEL)
related to rump.

hypercall interface:
src/lib/librumpuser
  The "rumpuser" set of interfaces is used by rump to communicate
  with the host.

Users:
src/lib
  /libp2k  - puffs-to-vfs adaption layer, userspace namespace
  /libukfs - user kernel file system, a library to access file system
	     images (or devices) directly in userspace without going
	     through a system call and puffs.  It provides a slightly
	     higher interface than pure rump syscalls.

src/usr.sbin/puffs
  rump_$fs - userspace file system daemons using the kernel fs code

src/share/examples/rump
  Various examples detailing use of rump in different scenarios.
  These are provided source-only.