'RELENG_6_0_0_RELEASE'.

This commit was manufactured to restore the state of the 6.0-RELEASE image.

whose version has not already been bumped since RELENG_5 are being
bumped.

Revisions of files being MFC-ed:

> Path						Revision
> src/gnu/lib/libdialog/Makefile		1.43
> src/gnu/lib/libg2c/Makefile			1.16
> src/gnu/lib/libobjc/Makefile			1.27
> src/gnu/lib/libreadline/Makefile.inc		1.12
> src/gnu/lib/libregex/Makefile			1.32
> src/gnu/lib/libstdc++/Makefile		1.56
> src/kerberos5/lib/Makefile.inc		1.7
> src/lib/Makefile.inc				1.3
> src/lib/libalias/Makefile			1.31
> src/lib/libarchive/Makefile			1.37
> src/lib/libbegemot/Makefile			1.3
> src/lib/libbluetooth/Makefile			1.2
> src/lib/libbsnmp/Makefile.inc			1.6
> src/lib/libbz2/Makefile			1.6
> src/lib/libc_r/Makefile			1.42
> src/lib/libcrypt/Makefile			1.36
> src/lib/libdevstat/Makefile			1.15
> src/lib/libdevstat/devstat.h			1.11
> src/lib/libedit/Makefile			1.29
> src/lib/libexpat/Makefile			1.5
> src/lib/libfetch/Makefile			1.45
> src/lib/libftpio/Makefile			1.14
> src/lib/libgpib/Makefile			1.2
> src/lib/libipsec/Makefile			1.17
> src/lib/libkiconv/Makefile			1.3
> src/lib/libmagic/Makefile			1.7
> src/lib/libmp/Makefile			1.10
> src/lib/libncp/Makefile			1.6
> src/lib/libncurses/Makefile			1.79
> src/lib/libnetgraph/Makefile			1.11
> src/lib/libngatm/Makefile			1.6
> src/lib/libopie/Makefile			1.21
> src/lib/libpam/Makefile.inc			1.17
> src/lib/libpthread/Makefile			1.54
> src/lib/libradius/Makefile			1.12
> src/lib/libsdp/Makefile			1.4
> src/lib/libsmb/Makefile			1.8
> src/lib/libtacplus/Makefile			1.7
> src/lib/libthr/Makefile			1.14
> src/lib/libthread_db/Makefile			1.6
> src/lib/libugidfw/Makefile			1.7
> src/lib/libusbhid/Makefile			1.10
> src/lib/libutil/Makefile			1.57
> src/lib/libvgl/Makefile			1.11
> src/lib/libwrap/Makefile			1.17
> src/lib/libypclnt/Makefile			1.13
> src/lib/msun/Makefile				1.72
> src/secure/lib/libcrypto/Makefile		1.74
> src/secure/lib/libssh/Makefile		1.35
> src/secure/lib/libssl/Makefile		1.22
> src/usr.sbin/bsnmpd/modules/Makefile.inc	1.10

Reviewed by:	ru
Approved by:	re (scottl)

Pointy hat to:	phk

to stay backwards compatible.

a couple of reqests:  DSM_BUSY_PCT and DSM_QUEUE_LENGTH.

I have no further plans for mutilating this API at this point in
time, and will update the man-page to reflect current reality as
the next thing.

Reviewed by:    ken

Kernel:

Change statistics to use the *uptime() timescale (ie: relative to
boottime) rather than the UTC aligned timescale.  This makes the
device statistics code oblivious to clock steps.

Change timestamps to bintime format, they are cheaper.

Remove the "busy_count", and replace it with two counter fields:
"start_count" and "end_count", which are updated in the down and
up paths respectively.  This removes the locking constraint on
devstat.

Add a timestamp argument to devstat_start_transaction(), this will
normally be a timestamp set by the *_bio() function in bp->bio_t0.
Use this field to calculate duration of I/O operations.

Add two timestamp arguments to devstat_end_transaction(), one is
the current time, a NULL pointer means "take timestamp yourself",
the other is the timestamp of when this transaction started (see
above).

Change calculation of busy_time to operate on "the salami principle":
Only when we are idle, which we can determine by the start+end
counts being identical, do we update the "busy_from" field in the
down path.  In the up path we accumulate the timeslice in busy_time
and update busy_from.

Change the byte_* and num_* fields into two arrays: bytes[] and
operations[].

Userland:

Change the misleading "busy_time" name to be called "snap_time" and
make the time long double since that is what most users need anyway,
fill it using clock_gettime(CLOCK_MONOTONIC) to put it on the same
timescale as the kernel fields.

Change devstat_compute_etime() to operate on struct bintime.

Remove the version 2 legacy interface: the change to bintime makes
compatibility far too expensive.

Fix a bug in systat's "vm" page where boot relative busy times would
be bogus.

Bump __FreeBSD_version to 500107

Review & Collaboration by:	ken

Submitted by:	"Sergey A. Osokin" <osa@freebsd.org.ru>

gets rid of the duplicated code in compute_stats().

Add a new DSM_SKIP statistic type for devstat_compute_statistics() that
causes the subsequent variable argument to be skipped.

Thanks to Sergey Osokin for coding up my idea/code fragment.

Submitted by:	"Sergey A. Osokin" <osa@freebsd.org.ru>

1.) prefix all functions in the library with devstat_ (compatability
    functions are available for all functions that were chaned in an
    incompatible way, but are deprecated).
2.) Add a pointer to a kvm_t as the first argument to functions that
    used to get their information via sysctl; they behave the same
    as before when NULL is passed as this argument, otherwise, the
    information is obtained via libkvm using the supplied handle.
3.) Add a new function, devstat_compute_statistics(), that is intended
    to replace the old compute_stats() function. It offers more
    statistics data, and has a more flexible interface.

libdevstat does now require libkvm; a library depedency is added, so
that libkvm only needs to be explicitely specified for statically linked
programs.
The library major version number is bumped.

Submitted by:	Sergey A. Osokin <osa@freebsd.org.ru>, ken (3)
Reviewed by:	ken