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Commit Graph

6390 Commits

Author SHA1 Message Date
Konstantin Belousov
80b5691a76 When reporting the fault details, also print %rsp.
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2013-05-27 18:29:20 +00:00
Konstantin Belousov
6806ce6ec8 When handling an exception from the attempt from loading the faulting
context on return from the trap handler, re-enable the interrupts on
i386 and amd64.  The trap return path have to disable interrupts since
the sequence of loading the machine state is not atomic.  The trap()
function which transfers the control to the special handler would
enable the interrupt, but an iret loads the previous eflags with PSL_I
clear.  Then, the special handler calls trap() on its own, which now
sees the original eflags with PSL_I set and does not enable
interrupts.

The end result is that signal delivery and process exiting code could
be executed with interrupts disabled, which is generally wrong and
triggers several assertions.

For amd64, the interrupts are enabled conditionally based on PSL_I in
the eflags of the outer frame, as it is already done for
doreti_iret_fault.  For i386, the interrupts are enabled
unconditionally, the ast loop could have opened a window with
interrupts enabled just before the iret anyway.

Reported and tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2013-05-27 18:26:08 +00:00
Achim Leubner
dce93cd06d Driver 'aacraid' added. Supports Adaptec by PMC RAID controller families Series 6, 7, 8 and upcoming products. Older Adaptec RAID controller families are supported by the 'aac' driver.
Approved by:	scottl (mentor)
2013-05-24 09:22:43 +00:00
Attilio Rao
9af6d512f5 o Relax locking assertions for vm_page_find_least()
o Relax locking assertions for pmap_enter_object() and add them also
  to architectures that currently don't have any
o Introduce VM_OBJECT_LOCK_DOWNGRADE() which is basically a downgrade
  operation on the per-object rwlock
o Use all the mechanisms above to make vm_map_pmap_enter() to work
  mostl of the times only with readlocks.

Sponsored by:	EMC / Isilon storage division
Reviewed by:	alc
2013-05-21 20:38:19 +00:00
Konstantin Belousov
4f493a25f4 Fix the hardware watchpoints on SMP amd64. Load the updated %dr
registers also on other CPUs, besides the CPU which happens to execute
the ddb.  The debugging registers are stored in the pcpu area,
together with the command which is executed by the IPI stop handler
upon resume.

Reviewed by:	jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2013-05-21 11:24:32 +00:00
Konstantin Belousov
ea38ca6ea5 Add amd64-specific ddb command 'show phys2dmap', which calculates the
address in the direct map corresponding to the given physical address.

Reviewed by:	jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2013-05-21 11:07:12 +00:00
Marcel Moolenaar
cb34ed4434 Add basic support for FDT to i386 & amd64. This change includes:
1.  Common headers for fdt.h and ofw_machdep.h under x86/include
    with indirections under i386/include and amd64/include.
2.  New modinfo for loader provided FDT blob.
3.  Common x86_init_fdt() called from hammer_time() on amd64 and
    init386() on i386.
4.  Split-off FDT specific low-level console functions from FDT
    bus methods for the uart(4) driver. The low-level console
    logic has been moved to uart_cpu_fdt.c and is used for arm,
    mips & powerpc only. The FDT bus methods are shared across
    all architectures.
5.  Add dev/fdt/fdt_x86.c to hold the fdt_fixup_table[] and the
    fdt_pic_table[] arrays. Both are empty right now.

FDT addresses are I/O ports on x86. Since the core FDT code does
not handle different address spaces, adding support for both I/O
ports and memory addresses requires some thought and discussion.
It may be better to use a compile-time option that controls this.

Obtained from:	Juniper Networks, Inc.
2013-05-21 03:05:49 +00:00
Ed Schouten
31ffd8039d Improve readability of static assertions for OFFSET_* macros.
Instead of doing all sorts of weird casting of constants to
pointer-pointers, simply use the standard C offsetof() macro to obtain
the offset of the respective fields in the structures.
2013-05-13 21:47:17 +00:00
Peter Wemm
dda759d344 Tidy up some CVS workarounds. 2013-05-12 01:53:47 +00:00
Rui Paulo
009b3a1c3f Fix several standard extended feature bits.
Submitted by:	Oliver Pinter <oliver.pntr at gmail.com>
2013-05-11 01:31:51 +00:00
Neel Natu
0acb0d84c5 Support array-type of stats in bhyve.
An array-type stat in vmm.ko is defined as follows:
VMM_STAT_ARRAY(IPIS_SENT, VM_MAXCPU, "ipis sent to vcpu");

It is incremented as follows:
vmm_stat_array_incr(vm, vcpuid, IPIS_SENT, array_index, 1);

And output of 'bhyvectl --get-stats' looks like:
ipis sent to vcpu[0]     3114
ipis sent to vcpu[1]     0

Reviewed by:	grehan
Obtained from:	NetApp
2013-05-10 02:59:49 +00:00
Dmitry Chagin
d127f15308 Retire write-only PCB_GS32BIT pcb flag on amd64. 2013-05-09 21:42:43 +00:00
Konstantin Belousov
241b67bb47 Correct the type for the literal used on the left side of the shift up
to 63 bit positions.

Do not fill the save area and do not set the saved bit in the xstate
bit vector for the state which is not marked as enabled in xsave_mask.

Reported and tested by:	Jim Ohlstein <jim@ohlste.in>
MFC after:	3 days
2013-05-09 17:25:29 +00:00
Attilio Rao
941646f5ec Rename VM_NDOMAIN into MAXMEMDOM and move it into machine/param.h in
order to match the MAXCPU concept.  The change should also be useful
for consolidation and consistency.

Sponsored by:	EMC / Isilon storage division
Obtained from:	jeff
Reviewed by:	alc
2013-05-07 22:46:24 +00:00
Ed Maste
f5efbffe52 Switch to standard copyright license text
The initial version of this came from Sandvine but had "PROVIDED BY NETAPP,
INC" in the copyright text, presuambly because the license block was copied
from another file.  Replace it with standard "AUTHOR AND CONTRIBUTORS" form.

Approvided by: grehan@
2013-05-02 12:35:15 +00:00
Konstantin Belousov
14f525595c Partially saved extended state must be handled always, i.e. for both
fpu-owned context, and for pcb-saved one.  More, the XSAVE could do
partial save, same as XSAVEOPT, so qualifier for the handler should be
use_xsave and not use_xsaveopt.

Since xsave_area_desc is now needed regardless of the XSAVEOPT use,
remove the write-only use_xsaveopt variable.

In collaboration with:	jhb
MFC after:	1 week
2013-05-01 20:08:33 +00:00
Konstantin Belousov
6f2d9906a9 The check to ensure that xstate_bv always has XFEATURE_ENABLED_X87 and
XFEATURE_ENABLED_SSE bits set is not needed.  CPU correctly handles
any bitmask which is subset of the enabled bits in %XCR0.

More, CPU instructions XSAVE and XSAVEOPT could write the mask without
e.g. XFEATURE_ENABLED_SSE, after the VZEROALL.  The check prevents the
restoration of the otherwise valid FPU save area.

In collaboration with:	jhb
MFC after:	1 week
2013-05-01 20:03:50 +00:00
Carl Delsey
e47937d1b7 Add a new driver to support the Intel Non-Transparent Bridge(NTB).
The NTB allows you to connect two systems with this device using a PCI-e
link. The driver is made of two modules:
 - ntb_hw which is a basic hardware abstraction layer for the device.
 - if_ntb which implements the ntb network device and the communication
   protocol.

The driver is limited at the moment to CPU memcpy instead of using DMA, and
only Back-to-Back mode is supported. Also the network device isn't full
featured yet. These changes will be coming soon. The DMA change will also
bring in the ioat driver from the project branch it is on now.

This is an initial port of the GPL/BSD Linux driver contributed by Jon Mason
from Intel. Any bugs are my contributions.

Sponsored by: Intel
Reviewed by: jimharris, joel (man page only)
Approved by: jimharris (mentor)
2013-04-29 22:48:53 +00:00
Peter Grehan
d3c11f40a5 Add RIP-relative addressing to the instruction decoder.
Rework the guest register fetch code to allow the RIP to
be extracted from the VMCS while the kernel decoder is
functioning.

Hit by the OpenBSD local-apic code.

Submitted by:	neel
Reviewed by:	grehan
Obtained from:	NetApp
2013-04-25 04:56:43 +00:00
Rui Paulo
068e8f74e4 Print RDSEED, ADX, and SMAP.
Pointed out by:	kib
2013-04-18 01:21:44 +00:00
Gabor Kovesdan
a8b5c2a0aa - Correct spelling in comments
Submitted by:	Christoph Mallon <christoph.mallon@gmx.de> (via private mail)
2013-04-17 11:56:11 +00:00
Rui Paulo
d1dcd93145 Print more bits from the standard extended features CPUID which will be
available in the Haswell architecture (c.f. Intel Document #319433-012A).
2013-04-17 06:51:17 +00:00
Neel Natu
3565b59ec0 Create sysctl node 'hw.vmm.vmx' and populate it with oids that expose the VMX
hardware capabilities.

Obtained from:	NetApp
2013-04-13 21:41:51 +00:00
Konstantin Belousov
fcb29b9210 Fix the name of the pcb member in the comments.
Submitted by:	Oliver Pinter <oliver.pntr@gmail.com>
MFC after:	3 days
2013-04-13 15:20:33 +00:00
Neel Natu
26d66b9d58 Use the MAKEDEV_CHECKNAME flag to check for an invalid device name and return
an error instead of panicking.

Obtained from:	NetApp
2013-04-13 05:11:21 +00:00
Edward Tomasz Napierala
8ed9860914 Remove ctl(4) from GENERIC. Also remove 'options CTL_DISABLE'
and kern.cam.ctl.disable tunable; those were introduced as a workaround
to make it possible to boot GENERIC on low memory machines.

With ctl(4) being built as a module and automatically loaded by ctladm(8),
this makes CTL work out of the box.

Reviewed by:	ken
Sponsored by:	FreeBSD Foundation
2013-04-12 16:25:03 +00:00
Neel Natu
d5408b1d26 If vmm.ko could not be initialized correctly then prevent the creation of
virtual machines subsequently.

Submitted by:	Chris Torek
2013-04-12 01:16:52 +00:00
Neel Natu
150369ab7c Make the code to check if VMX is enabled more readable by using macros
instead of magic numbers.

Discussed with:	Chris Torek
2013-04-11 04:29:45 +00:00
Neel Natu
1472b87f2f Unsynchronized TSCs on the host require special handling in bhyve:
- use clock_gettime(2) as the time base for the emulated ACPI timer instead
  of directly using rdtsc().

- don't advertise the invariant TSC capability to the guest to discourage it
  from using the TSC as its time base.

Discussed with:	jhb@ (about making 'smp_tsc' a global)
Reported by:	Dan Mack on freebsd-virtualization@
Obtained from:	NetApp
2013-04-10 05:59:07 +00:00
Gleb Smirnoff
4e76af6a41 Merge from projects/counters: counter(9).
Introduce counter(9) API, that implements fast and raceless counters,
provided (but not limited to) for gathering of statistical data.

See http://lists.freebsd.org/pipermail/freebsd-arch/2013-April/014204.html
for more details.

In collaboration with:	kib
Reviewed by:		luigi
Tested by:		ae, ray
Sponsored by:		Nginx, Inc.
2013-04-08 19:40:53 +00:00
Gleb Smirnoff
17dece86fe Merge from projects/counters:
Pad struct pcpu so that its size is denominator of PAGE_SIZE. This
is done to reduce memory waste in UMA_PCPU_ZONE zones.

Sponsored by:	Nginx, Inc.
2013-04-08 19:19:10 +00:00
Peter Grehan
117e8f378e Don't panic when a valid divisor of 1 has been requested.
Obtained from:	NetApp
2013-04-05 22:16:31 +00:00
Alexander Motin
45f6d66569 Remove all legacy ATA code parts, not used since options ATA_CAM enabled in
most kernels before FreeBSD 9.0.  Remove such modules and respective kernel
options: atadisk, ataraid, atapicd, atapifd, atapist, atapicam.  Remove the
atacontrol utility and some man pages.  Remove useless now options ATA_CAM.

No objections:	current@, stable@
MFC after:	never
2013-04-04 07:12:24 +00:00
Neel Natu
77d8fd9bb3 Add counter to keep track of the number of timer interrupts generated by
the local apic for each virtual cpu.
2013-03-31 03:56:48 +00:00
Neel Natu
b5aaf7b22b Add some more stats to keep track of all the reasons that a vcpu is exiting. 2013-03-30 17:46:03 +00:00
Neel Natu
66f71b7d24 Allow caller to skip 'guest linear address' validation when doing instruction
decode. This is to accomodate hardware assist implementations that do not
provide the 'guest linear address' as part of nested page fault collateral.

Submitted by:	Anish Gupta (akgupt3 at gmail dot com)
2013-03-28 21:26:19 +00:00
Konstantin Belousov
ee75e7de7b Implement the concept of the unmapped VMIO buffers, i.e. buffers which
do not map the b_pages pages into buffer_map KVA.  The use of the
unmapped buffers eliminate the need to perform TLB shootdown for
mapping on the buffer creation and reuse, greatly reducing the amount
of IPIs for shootdown on big-SMP machines and eliminating up to 25-30%
of the system time on i/o intensive workloads.

The unmapped buffer should be explicitely requested by the GB_UNMAPPED
flag by the consumer.  For unmapped buffer, no KVA reservation is
performed at all. The consumer might request unmapped buffer which
does have a KVA reserve, to manually map it without recursing into
buffer cache and blocking, with the GB_KVAALLOC flag.

When the mapped buffer is requested and unmapped buffer already
exists, the cache performs an upgrade, possibly reusing the KVA
reservation.

Unmapped buffer is translated into unmapped bio in g_vfs_strategy().
Unmapped bio carry a pointer to the vm_page_t array, offset and length
instead of the data pointer.  The provider which processes the bio
should explicitely specify a readiness to accept unmapped bio,
otherwise g_down geom thread performs the transient upgrade of the bio
request by mapping the pages into the new bio_transient_map KVA
submap.

The bio_transient_map submap claims up to 10% of the buffer map, and
the total buffer_map + bio_transient_map KVA usage stays the
same. Still, it could be manually tuned by kern.bio_transient_maxcnt
tunable, in the units of the transient mappings.  Eventually, the
bio_transient_map could be removed after all geom classes and drivers
can accept unmapped i/o requests.

Unmapped support can be turned off by the vfs.unmapped_buf_allowed
tunable, disabling which makes the buffer (or cluster) creation
requests to ignore GB_UNMAPPED and GB_KVAALLOC flags.  Unmapped
buffers are only enabled by default on the architectures where
pmap_copy_page() was implemented and tested.

In the rework, filesystem metadata is not the subject to maxbufspace
limit anymore. Since the metadata buffers are always mapped, the
buffers still have to fit into the buffer map, which provides a
reasonable (but practically unreachable) upper bound on it. The
non-metadata buffer allocations, both mapped and unmapped, is
accounted against maxbufspace, as before. Effectively, this means that
the maxbufspace is forced on mapped and unmapped buffers separately.
The pre-patch bufspace limiting code did not worked, because
buffer_map fragmentation does not allow the limit to be reached.

By Jeff Roberson request, the getnewbuf() function was split into
smaller single-purpose functions.

Sponsored by:	The FreeBSD Foundation
Discussed with:	jeff (previous version)
Tested by:	pho, scottl (previous version), jhb, bf
MFC after:	2 weeks
2013-03-19 14:13:12 +00:00
Attilio Rao
774d251d99 Sync back vmcontention branch into HEAD:
Replace the per-object resident and cached pages splay tree with a
path-compressed multi-digit radix trie.
Along with this, switch also the x86-specific handling of idle page
tables to using the radix trie.

This change is supposed to do the following:
- Allowing the acquisition of read locking for lookup operations of the
  resident/cached pages collections as the per-vm_page_t splay iterators
  are now removed.
- Increase the scalability of the operations on the page collections.

The radix trie does rely on the consumers locking to ensure atomicity of
its operations.  In order to avoid deadlocks the bisection nodes are
pre-allocated in the UMA zone.  This can be done safely because the
algorithm needs at maximum one new node per insert which means the
maximum number of the desired nodes is the number of available physical
frames themselves.  However, not all the times a new bisection node is
really needed.

The radix trie implements path-compression because UFS indirect blocks
can lead to several objects with a very sparse trie, increasing the number
of levels to usually scan.  It also helps in the nodes pre-fetching by
introducing the single node per-insert property.

This code is not generalized (yet) because of the possible loss of
performance by having much of the sizes in play configurable.
However, efforts to make this code more general and then reusable in
further different consumers might be really done.

The only KPI change is the removal of the function vm_page_splay() which
is now reaped.
The only KBI change, instead, is the removal of the left/right iterators
from struct vm_page, which are now reaped.

Further technical notes broken into mealpieces can be retrieved from the
svn branch:
http://svn.freebsd.org/base/user/attilio/vmcontention/

Sponsored by:	EMC / Isilon storage division
In collaboration with:	alc, jeff
Tested by:	flo, pho, jhb, davide
Tested by:	ian (arm)
Tested by:	andreast (powerpc)
2013-03-18 00:25:02 +00:00
Neel Natu
3f23d3ca9f Fix the '-Wtautological-compare' warning emitted by clang for comparing the
unsigned enum type with a negative value.

Obtained from:	NetApp
2013-03-16 22:53:05 +00:00
Neel Natu
61592433eb Allow vmm stats to be specific to the underlying hardware assist technology.
This can be done by using the new macros VMM_STAT_INTEL() and VMM_STAT_AMD().
Statistic counters that are common across the two are defined using VMM_STAT().

Suggested by:	Anish Gupta
Discussed with:	grehan
Obtained from:	NetApp
2013-03-16 22:40:20 +00:00
Konstantin Belousov
e8a4a618cf Add pmap function pmap_copy_pages(), which copies the content of the
pages around, taking array of vm_page_t both for source and
destination.  Starting offsets and total transfer size are specified.

The function implements optimal algorithm for copying using the
platform-specific optimizations.  For instance, on the architectures
were the direct map is available, no transient mappings are created,
for i386 the per-cpu ephemeral page frame is used.  The code was
typically borrowed from the pmap_copy_page() for the same
architecture.

Only i386/amd64, powerpc aim and arm/arm-v6 implementations were
tested at the time of commit. High-level code, not committed yet to
the tree, ensures that the use of the function is only allowed after
explicit enablement.

For sparc64, the existing code has known issues and a stab is added
instead, to allow the kernel linking.

Sponsored by:	The FreeBSD Foundation
Tested by:	pho (i386, amd64), scottl (amd64), ian (arm and arm-v6)
MFC after:	2 weeks
2013-03-14 20:18:12 +00:00
Alan Cox
9f585991ba The kernel pmap is statically allocated, so there is really no need to
explicitly initialize its pm_root field to zero.

Sponsored by:	EMC / Isilon Storage Division
2013-03-10 21:07:44 +00:00
Attilio Rao
89f6b8632c Switch the vm_object mutex to be a rwlock. This will enable in the
future further optimizations where the vm_object lock will be held
in read mode most of the time the page cache resident pool of pages
are accessed for reading purposes.

The change is mostly mechanical but few notes are reported:
* The KPI changes as follow:
  - VM_OBJECT_LOCK() -> VM_OBJECT_WLOCK()
  - VM_OBJECT_TRYLOCK() -> VM_OBJECT_TRYWLOCK()
  - VM_OBJECT_UNLOCK() -> VM_OBJECT_WUNLOCK()
  - VM_OBJECT_LOCK_ASSERT(MA_OWNED) -> VM_OBJECT_ASSERT_WLOCKED()
    (in order to avoid visibility of implementation details)
  - The read-mode operations are added:
    VM_OBJECT_RLOCK(), VM_OBJECT_TRYRLOCK(), VM_OBJECT_RUNLOCK(),
    VM_OBJECT_ASSERT_RLOCKED(), VM_OBJECT_ASSERT_LOCKED()
* The vm/vm_pager.h namespace pollution avoidance (forcing requiring
  sys/mutex.h in consumers directly to cater its inlining functions
  using VM_OBJECT_LOCK()) imposes that all the vm/vm_pager.h
  consumers now must include also sys/rwlock.h.
* zfs requires a quite convoluted fix to include FreeBSD rwlocks into
  the compat layer because the name clash between FreeBSD and solaris
  versions must be avoided.
  At this purpose zfs redefines the vm_object locking functions
  directly, isolating the FreeBSD components in specific compat stubs.

The KPI results heavilly broken by this commit.  Thirdy part ports must
be updated accordingly (I can think off-hand of VirtualBox, for example).

Sponsored by:	EMC / Isilon storage division
Reviewed by:	jeff
Reviewed by:	pjd (ZFS specific review)
Discussed with:	alc
Tested by:	pho
2013-03-09 02:32:23 +00:00
Bryan Venteicher
0cfbcf8c7b Remove the virtio dependency entry for the VirtIO device drivers. This
will prevent the kernel from linking if the device driver are included
without the virtio module. Remove pci and scbus for the same reason.

Also explain the relationship and necessity of the virtio and virtio_pci
modules. Currently in FreeBSD, we only support VirtIO PCI, but it could
be replaced with a different interface (like MMIO) and the device
(network, block, etc) will still function.

Requested by:	luigi
Approved by:	grehan (mentor)
MFC after:	3 days
2013-03-06 07:17:53 +00:00
Kenneth D. Merry
3a45b4781a Re-enable CTL in GENERIC on i386 and amd64, but turn on the CTL disable
tunable by default.

This will allow GENERIC configurations to boot on small memory boxes, but
not require end users who want to use CTL to recompile their kernel.  They
can simply set kern.cam.ctl.disable=0 in loader.conf.

The eventual solution to the memory usage problem is to change the way
CTL allocates memory to be more configurable, but this should fix things
for small memory situations in the mean time.

UPDATING:		Explain the change in the CTL configuration, and
			how users can enable CTL if they would like to use
			it.

sys/conf/options:	Add a new option, CTL_DISABLE, that prevents CTL
			from initializing.

ctl.c:			If CTL_DISABLE is turned on, don't initialize.

i386/conf/GENERIC,
amd64/conf/GENERIC:	Re-enable device ctl, and add the CTL_DISABLE
			option.
2013-03-04 21:18:45 +00:00
Attilio Rao
b38d37f7b5 Merge from vmc-playground branch:
Rename the pv_entry_t iterator from pv_list to pv_next.
Besides being more correct technically (as the name seems to suggest
this is a list while it is an iterator), it will also be needed by
vm_radix work to avoid a nameclash on macro expansions.

Sponsored by:	EMC / Isilon storage division
Reviewed by:	alc, jeff
Tested by:	flo, pho, jhb, davide
2013-03-02 14:19:08 +00:00
Adrian Chadd
fe138cc2af Disable the ctl driver in GENERIC.
It unfortunately steals a fair chunk of RAM at startup even if it's not
actively used, which prevents FreeBSD VMs of 128MB from successfully
booting and running.
2013-03-02 08:12:41 +00:00
Davide Italiano
acccf7d8b4 MFcalloutng:
When CPU becomes idle, cpu_idleclock() calculates time to the next timer
event in order to reprogram hw timer. Return that time in sbintime_t to
the caller and pass it to acpi_cpu_idle(), where it can be used as one
more factor (quite precise) to extimate furter sleep time and choose
optimal sleep state. This is a preparatory change for further callout
improvements will be committed in the next days.

The commmit is not targeted for MFC.
2013-02-28 10:46:54 +00:00
Attilio Rao
dc1558d1cd Merge from vmobj-rwlock:
VM_OBJECT_LOCKED() macro is only used to implement a custom version
of lock assertions right now (which likely spread out thanks to
copy and paste).
Remove it and implement actual assertions.

Sponsored by:	EMC / Isilon storage division
Reviewed by:	alc
Tested by:	pho
2013-02-27 18:12:13 +00:00
Konstantin Belousov
31a53cd036 Convert machine/elf.h, machine/frame.h, machine/sigframe.h,
machine/signal.h and machine/ucontext.h into common x86 includes,
copying from amd64 and merging with i386.

Kernel-only compat definitions are kept in the i386/include/sigframe.h
and i386/include/signal.h, to reduce amd64 kernel namespace pollution.
The amd64 compat uses its own definitions so far.

The _MACHINE_ELF_WANT_32BIT definition is to allow the
sys/boot/userboot/userboot/elf32_freebsd.c to use i386 ELF definitions
on the amd64 compile host.  The same hack could be usefully abused by
other code too.
2013-02-20 17:39:52 +00:00