History log of /arch/mips/sgi-ip27/ip27-irq.c
Revision Date Author Comments
8ea2b8b605d0053fc87abde56ff42b19520322f0 13-Jun-2013 Ralf Baechle <ralf@linux-mips.org> MIPS: IP27: Fix build errors with CONFIG_PCI disabled.

LD init/built-in.o
arch/mips/built-in.o: In function `startup_bridge_irq':
ip27-irq.c:(.text+0x434): undefined reference to `irq_to_slot'
ip27-irq.c:(.text+0x43c): undefined reference to `irq_to_slot'
ip27-irq.c:(.text+0x460): undefined reference to `irq_to_bridge'
ip27-irq.c:(.text+0x464): undefined reference to `irq_to_bridge'
arch/mips/built-in.o: In function `shutdown_bridge_irq':
ip27-irq.c:(.text+0x564): undefined reference to `irq_to_bridge'
ip27-irq.c:(.text+0x56c): undefined reference to `irq_to_bridge'
ip27-irq.c:(.text+0x5a0): undefined reference to `irq_to_slot'
ip27-irq.c:(.text+0x5a4): undefined reference to `irq_to_slot'

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
7034228792cc561e79ff8600f02884bd4c80e287 22-Jan-2013 Ralf Baechle <ralf@linux-mips.org> MIPS: Whitespace cleanup.

Having received another series of whitespace patches I decided to do this
once and for all rather than dealing with this kind of patches trickling
in forever.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
b81947c646bfefdf98e2fde5d7d39cbbda8525d4 28-Mar-2012 David Howells <dhowells@redhat.com> Disintegrate asm/system.h for MIPS

Disintegrate asm/system.h for MIPS.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
cc: linux-mips@linux-mips.org
8b5690f8847490c1e3ea47266819833a13621253 22-Nov-2011 Yong Zhang <yong.zhang0@gmail.com> MIPS: irq: Remove IRQF_DISABLED

Since commit [e58aa3d2: genirq: Run irq handlers with interrupts disabled],
We run all interrupt handlers with interrupts disabled and we even check
and yell when an interrupt handler returns with interrupts enabled (see
commit [b738a50a: genirq: Warn when handler enables interrupts]).

So now this flag is a NOOP and can be removed.

[ralf@linux-mips.org: Fixed up conflicts in
arch/mips/alchemy/common/dbdma.c, arch/mips/cavium-octeon/smp.c and
arch/mips/kernel/perf_event.c.]

Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
To: linux-kernel@vger.kernel.org
Cc: tglx@linutronix.de
linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2835/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
ab75dc02c151c9d2a2fd446334d740b097a3b9db 17-Nov-2011 Ralf Baechle <ralf@linux-mips.org> MIPS: Fix up inconsistency in panic() string argument.

Panic() invokes printk() to add a \n internally, so panic arguments should
not themselves end in \n. Panic invocations in arch/mips and elsewhere
are inconsistently sometimes terminating in \n, sometimes not.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
901f6169400bcfcde7da71695c57388da0a515e5 22-Jun-2011 Ralf Baechle <ralf@linux-mips.org> MIPS: IP27: Sort out section mismatch.

WARNING: vmlinux.o(.text+0x3059f8): Section mismatch in reference from the function pcibios_plat_dev_init() to the function .devinit.text:request_bridge_irq()
The function pcibios_plat_dev_init() references
the function __devinit request_bridge_irq().
This is often because pcibios_plat_dev_init lacks a __devinit
annotation or the annotation of request_bridge_irq is wrong.

Fixing this one leads to:

WARNING: vmlinux.o(.text+0x1790): Section mismatch in reference from the function request_bridge_irq() to the function .devinit.text:register_bridge_irq()
The function request_bridge_irq() references
the function __devinit register_bridge_irq().
This is often because request_bridge_irq lacks a __devinit
annotation or the annotation of register_bridge_irq is wrong.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
184748cc50b2dceb8287f9fb657eda48ff8fcfe7 05-Apr-2011 Peter Zijlstra <a.p.zijlstra@chello.nl> sched: Provide scheduler_ipi() callback in response to smp_send_reschedule()

For future rework of try_to_wake_up() we'd like to push part of that
function onto the CPU the task is actually going to run on.

In order to do so we need a generic callback from the existing scheduler IPI.

This patch introduces such a generic callback: scheduler_ipi() and
implements it as a NOP.

BenH notes: PowerPC might use this IPI on offline CPUs under rare conditions!

Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Reviewed-by: Frank Rowand <frank.rowand@am.sony.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110405152728.744338123@chello.nl
25985edcedea6396277003854657b5f3cb31a628 31-Mar-2011 Lucas De Marchi <lucas.demarchi@profusion.mobi> Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
e4ec7989b4e55d9275ebac66230b7dac6dcb1fae 27-Mar-2011 Thomas Gleixner <tglx@linutronix.de> MIPS: Convert the irq functions to the new names

Scripted with coccinelle.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
301218df9c07e675e1c5497c818df13bb7fc38b1 23-Mar-2011 Thomas Gleixner <tglx@linutronix.de> MIPS: IP27: Convert to new irq_chip functions

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2203/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
5a0e3ad6af8660be21ca98a971cd00f331318c05 24-Mar-2010 Tejun Heo <tj@kernel.org> include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
631330f5847b3f8a7ea67d689e9f7c56833ccaa6 19-Jun-2009 Ralf Baechle <ralf@linux-mips.org> MIPS: Build fix - include <linux/smp.h> into all smp_processor_id() users.

Some of the were relying into smp.h being dragged in by another header
which of course is fragile. <asm/cpu-info.h> uses smp_processor_id()
only in macros and including smp.h there leads to an include loop, so
don't change cpu-info.h.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
e887b24592c5ddf46d37e592b2ee6bd2188257e1 18-Oct-2007 Ralf Baechle <ralf@linux-mips.org> [MIPS] IP27: Convert to clock_event_device.

This separates the tick timer stuff from the generic MIPS time.c.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
52625caaee4930995ab25e0855713a7a2dd89151 27-Aug-2007 Ralf Baechle <ralf@linux-mips.org> [MIPS] IP27: intr_sconnect_level: don't disable interrupts.

There is no reason to.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
84ced30675b1454f1c2dca1fe055ae75eb1df53e 27-Aug-2007 Ralf Baechle <ralf@linux-mips.org> [MIPS] IP27: startup_bridge_irq: connect interrupt.

shutdown_bridge_irq disconnects the irq so we need to connect the irq or
requesting the same irq a send time will fail. This used to make
things like ifconfig eth0 down; ifconfig eth0 up fail on IP27.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
ed7a2365062bc9968e8e01423a889a95e85fba80 27-Aug-2007 Ralf Baechle <ralf@linux-mips.org> [MIPS] IP27: shutdown_bridge_irq: don't free irq.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
e63340ae6b6205fef26b40a75673d1c9c0c8bb90 08-May-2007 Randy Dunlap <randy.dunlap@oracle.com> header cleaning: don't include smp_lock.h when not used

Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.

Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
70d21cdeef6331e67ed87262c894cd6601f0dccc 14-Jan-2007 Atsushi Nemoto <anemo@mba.ocn.ne.jp> [MIPS] use name instead of typename for each irq_chip

The "typename" field was obsoleted by the "name" field.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
e77c232cfc6e1250b2916a7c69225d6634d05a49 01-Dec-2006 Franck Bui-Huu <fbuihuu@gmail.com> [MIPS] Compile __do_IRQ() when really needed

__do_IRQ() is needed only by irq handlers that can't use
default handlers defined in kernel/irq/chip.c.

For others platforms there's no need to compile this function
since it won't be used. For those platforms this patch defines
GENERIC_HARDIRQS_NO__DO_IRQ symbol which is used exactly for
this purpose.

Futhermore for platforms which do not use __do_IRQ(), end()
method which is part of the 'irq_chip' structure is not used.
This patch simply removes this method in this case.

Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
1417836e81c0ab8f5a0bfeafa90d3eaa41b2a067 13-Nov-2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp> [MIPS] use generic_handle_irq, handle_level_irq, handle_percpu_irq

Further incorporation of generic irq framework. Replacing __do_IRQ()
by proper flow handler would make the irq handling path a bit simpler
and faster.

* use generic_handle_irq() instead of __do_IRQ().
* use handle_level_irq for obvious level-type irq chips.
* use handle_percpu_irq for irqs marked as IRQ_PER_CPU.
* setup .eoi routine for irq chips possibly used with handle_percpu_irq.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
1603b5aca4f15b34848fb5594d0c7b6333b99144 01-Nov-2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp> [MIPS] IRQ cleanups

This is a big irq cleanup patch.

* Use set_irq_chip() to register irq_chip.
* Initialize .mask, .unmask, .mask_ack field. Functions for these
method are already exist in most case.
* Do not initialize .startup, .shutdown, .enable, .disable fields if
default routines provided by irq_chip_set_defaults() were suitable.
* Remove redundant irq_desc initializations.
* Remove unnecessary local_irq_save/local_irq_restore, spin_lock.

With this cleanup, it would be easy to switch to slightly lightwait
irq flow handlers (handle_level_irq(), etc.) instead of __do_IRQ().

Though whole this patch is quite large, changes in each irq_chip are
not quite simple. Please review and test on your platform. Thanks.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
4a4cf77923eeb3cec40a302656d6ab5ced04ba48 06-Nov-2006 Ralf Baechle <ralf@linux-mips.org> [MIPS] Make irq number allocator generally available for fixing EV64120.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
27f768192fe2d96936cef5d4713e228daee07ae2 09-Oct-2006 Ralf Baechle <ralf@linux-mips.org> [MIPS] Cleanup unnecessary <asm/ptrace.h> inclusions.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
937a801576f954bd030d7c4a5a94571710d87c0b 07-Oct-2006 Ralf Baechle <ralf@linux-mips.org> [MIPS] Complete fixes after removal of pt_regs argument to int handlers.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
94dee171df34b7955cd647da4c40ba67d55a7671 02-Jul-2006 Ralf Baechle <ralf@linux-mips.org> [MIPS] Eleminate interrupt migration helper use.

> #define hw_interrupt_type irq_chip
> typedef struct irq_chip hw_irq_controller;
> #define no_irq_type no_irq_chip
> typedef struct irq_desc irq_desc_t;

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
8717433ccae06788e58d55699027b47d042be1f4 25-Jun-2006 Ralf Baechle <ralf@linux-mips.org> [MIPS] IP27: Don't destroy interrupt routing information on shutdown irq.

This fixes the "not syncing: Could not identify cpu/level ..." panic
when a PCI irq is requested the second time.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
f40298fddcc3c8115c6135c9733f5a0de52dcea9 02-Jul-2006 Thomas Gleixner <tglx@linutronix.de> [PATCH] irq-flags: MIPS: Use the new IRQF_ constants

Use the new IRQF_ constants and remove the SA_INTERRUPT define

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
6ab3d5624e172c553004ecc862bfeac16d9d68b7 30-Jun-2006 Jörn Engel <joern@wohnheim.fh-wedel.de> Remove obsolete #include <linux/config.h>

Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
d1bef4ed5faf7d9872337b33c4269e45ae1bf960 29-Jun-2006 Ingo Molnar <mingo@elte.hu> [PATCH] genirq: rename desc->handler to desc->chip

This patch-queue improves the generic IRQ layer to be truly generic, by adding
various abstractions and features to it, without impacting existing
functionality.

While the queue can be best described as "fix and improve everything in the
generic IRQ layer that we could think of", and thus it consists of many
smaller features and lots of cleanups, the one feature that stands out most is
the new 'irq chip' abstraction.

The irq-chip abstraction is about describing and coding and IRQ controller
driver by mapping its raw hardware capabilities [and quirks, if needed] in a
straightforward way, without having to think about "IRQ flow"
(level/edge/etc.) type of details.

This stands in contrast with the current 'irq-type' model of genirq
architectures, which 'mixes' raw hardware capabilities with 'flow' details.
The patchset supports both types of irq controller designs at once, and
converts i386 and x86_64 to the new irq-chip design.

As a bonus side-effect of the irq-chip approach, chained interrupt controllers
(master/slave PIC constructs, etc.) are now supported by design as well.

The end result of this patchset intends to be simpler architecture-level code
and more consolidation between architectures.

We reused many bits of code and many concepts from Russell King's ARM IRQ
layer, the merging of which was one of the motivations for this patchset.

This patch:

rename desc->handler to desc->chip.

Originally i did not want to do this, because it's a big patch. But having
both "desc->handler", "desc->handle_irq" and "action->handler" caused a
large degree of confusion and made the code appear alot less clean than it
truly is.

I have also attempted a dual approach as well by introducing a
desc->chip alias - but that just wasnt robust enough and broke
frequently.

So lets get over with this quickly. The conversion was done automatically
via scripts and converts all the code in the kernel.

This renaming patch is the first one amongst the patches, so that the
remaining patches can stay flexible and can be merged and split up
without having some big monolithic patch act as a merge barrier.

[akpm@osdl.org: build fix]
[akpm@osdl.org: another build fix]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
3c0094426f3ff37697062b940211712746419688 16-Jun-2006 Ralf Baechle <ralf@linux-mips.org> [MIPS] IP27: Fix collision with hardcoded interrupt number.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
e4ac58afdfac792c0583af30dbd9eae53e24c78b 03-Apr-2006 Ralf Baechle <ralf@linux-mips.org> [MIPS] Rewrite all the assembler interrupt handlers to C.

Saves like 1,600 lines of code, is way easier to debug, compilers
frequently do a better job than the cut and paste type of handlers many
boards had. And finally having all the stuff done in a single place
also means alot of bug potencial for the MT ASE is gone.

The only surviving handler in assembler is the DECstation one; I hope
Maciej will rewrite it.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
394e3902c55e667945f6f1c2bdbc59842cce70f7 23-Mar-2006 Andrew Morton <akpm@osdl.org> [PATCH] more for_each_cpu() conversions

When we stop allocating percpu memory for not-possible CPUs we must not touch
the percpu data for not-possible CPUs at all. The correct way of doing this
is to test cpu_possible() or to use for_each_cpu().

This patch is a kernel-wide sweep of all instances of NR_CPUS. I found very
few instances of this bug, if any. But the patch converts lots of open-coded
test to use the preferred helper macros.

Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Acked-by: Kyle McMartin <kyle@parisc-linux.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Christian Zankel <chris@zankel.net>
Cc: Philippe Elie <phil.el@wanadoo.fr>
Cc: Nathan Scott <nathans@sgi.com>
Cc: Jens Axboe <axboe@suse.de>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
d3ffd085536c1801da74c098e25fd3985671e15d 08-Aug-2005 Ralf Baechle <ralf@linux-mips.org> Use pr_debug instead of homegrown debug print macros.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
1342f7e6c57f1ee04d27ee8c0c2f929f9803554a 14-Apr-2005 Ralf Baechle <ralf@linux-mips.org> Arrested for multiple offences of header file inclusion.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
4f12bfe5a498747a9a66f135a67aa8e1caa819dc 21-Mar-2005 Ralf Baechle <ralf@linux-mips.org> HUB interrupts are allocated per node, not per slice. Make manipulation
of the interrupt mask register atomic by disabling interrupts.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 17-Apr-2005 Linus Torvalds <torvalds@ppc970.osdl.org> Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!