Revert r330897:

This was intended to be a non-functional change. It wasn't. The commit
message was thus wrong. In addition it broke arm, and merged crypto
related code.

Revert with prejudice.

This revert skips files touched in r316370 since that commit was since
MFCed. This revert also skips files that require $FreeBSD$ property
changes.

Thank you to those who helped me get out of this mess including but not
limited to gonzo, kevans, rgrimes.

Requested by: gjb (re)

Partial merge of the SPDX changes

These changes are incomplete but are making it difficult
to determine what other changes can/should be merged.

No objections from: pfg

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Unbreak high resolution profiling a little: use dummy asms to prevent
timing loops being optimized away.

Once apon a time, gcc promised not to optimize away timing loops, but
gcc started optimizing away the call to a null function in the timing
loop here some time between gcc-3.3.3 and gcc-3.4.6, and it started
optimizing away the timing loop itself some time between gcc-3.4.6
and gcc-4.2.

Move the kernel-specific logic to adjust frompc from MI to MD. For
these two reasons:
1. On ia64 a function pointer does not hold the address of the first
instruction of a functions implementation. It holds the address
of a function descriptor. Hence the user(), btrap(), eintr() and
bintr() prototypes are wrong for getting the actual code address.
2. The logic forces interrupt, trap and exception entry points to
be layed-out contiguously. This can not be achieved on ia64 and is
generally just bad programming.

The MCOUNT_FROMPC_USER macro is used to set the frompc argument to
some kernel address which represents any frompc that falls outside
the kernel text range. The macro can expand to ~0U to bail out in
that case.
The MCOUNT_FROMPC_INTR macro is used to set the frompc argument to
some kernel address to represent a call to a trap or interrupt
handler. This to avoid that the trap or interrupt handler appear to
be called from everywhere in the call graph. The macro can expand
to ~0U to prevent adjusting frompc. Note that the argument is selfpc,
not frompc.

This commit defines the macros on all architectures equivalently to
the original code in sys/libkern/mcount.c. People can take it from
here...

Compile-tested on: alpha, amd64, i386, ia64 and sparc64
Boot-tested on: i386

Remove advertising clause from University of California Regent's
license, per letter dated July 22, 1999 and email from Peter Wemm,
Alan Cox and Robert Watson.

Approved by: core, peter, alc, rwatson

Use __FBSDID().

Remove __P.

We do not have UPAGES following the tail end of the user VM space anymore.

RIP <machine/lock.h>.

Some things needed bits of <i386/include/lock.h> - cy.c now has its
own (only) copy of the COM_(UN)LOCK() macros, and IMASK_(UN)LOCK()
has been moved to <i386/include/apic.h> (AKA <machine/apic.h>).
Reviewed by: jhb

Fix compilation of profiled kernels by including <machine/lock.h>

Change #ifdef KERNEL to #ifdef _KERNEL in the public headers. "KERNEL"
is an application space macro and the applications are supposed to be free
to use it as they please (but cannot). This is consistant with the other
BSD's who made this change quite some time ago. More commits to come.

$Id$ -> $FreeBSD$

Converted rcsid to $Id$ again. There shouldn't be any rcsids in the kernel.

Changed to the C9x draft spelling of the (unsigned) integral type
suitable for holding object pointers (ptrint_t -> uintptr_t).
Added corresponding signed type (intptr_t). Changed/added
corresponding non-C9x types for function pointers to match. Don't
use nonstandard types to implement these types, and don't comment
on them in <machine/types.h>.

Back out part 1 of the MCFH that changed $Id$ to $FreeBSD$. We are not
ready for it yet.

Make the long-awaited change from $Id$ to $FreeBSD$

This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.

Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.

Unremoved used #include of <sys/systm.h> for the !GUPROF case.

Improved non-statistical (GUPROF) profiling:
- use a more accurate and more efficient method of compensating for
overheads. The old method counted too much time against leaf
functions.
- normally use the Pentium timestamp counter if available.
On Pentiums, the times are now accurate to within a couple of cpu
clock cycles per function call in the (unlikely) event that there
are no cache misses in or caused by the profiling code.
- optionally use an arbitrary Pentium event counter if available.
- optionally regress to using the i8254 counter.
- scaled the i8254 counter by a factor of 128. Now the i8254 counters
overflow slightly faster than the TSC counters for a 150MHz Pentium :-)
(after about 16 seconds). This is to avoid fractional overheads.

files.i386:
permon.c temporarily has to be classified as a profiling-routine
because a couple of functions in it may be called from profiling code.

options.i386:
- I586_CTR_GUPROF is currently unused (oops).
- I586_PMC_GUPROF should be something like 0x70000 to enable (but not
use unless prof_machdep.c is changed) support for Pentium event
counters. 7 is a control mode and the counter number 0 is somewhere
in the 0000 bits (see perfmon.h for the encoding).

profile.h:
- added declarations.
- cleaned up separation of user mode declarations.

prof_machdep.c:
Mostly clock-select changes. The default clock can be changed by
editing kmem. There should be a sysctl for this.

subr_prof.c:
- added copyright.
- calibrate overheads for the new method.
- documented new method.
- fixed races and and machine dependencies in start/stop code.

mcount.c:
Use the new overhead compensation method.

gmon.h:
- changed GPROF4 counter type from unsigned to int. Oops, this should
be machine-dependent and/or int32_t.
- reorganized overhead counters.

Submitted by: Pentium event counter changes mostly by wollman

Cleaned up interrupt masking by declaring the state variable in a
machine-dependent macro and passing it to all machine-dependent
macros.

Eliminated the state variable for the GUPROF case.

removed:
CLBYTES PD_SHIFT PGSHIFT NBPG PGOFSET CLSIZELOG2 CLSIZE pdei()
ptei() kvtopte() ptetov() ispt() ptetoav() &c &c
new:
NPDEPG

Major macro cleanup.

Copied mcount.c from the library again. #include'ing it via a relative
path to a possibly-nonexistent place didn't work well enough. Sigh.

Implemented non-statistical kernel profiling. This is based on
looking at a high resolution clock for each of the following events:
function call, function return, interrupt entry, interrupt exit,
and interesting branches. The differences between the times of
these events are added at appropriate places in a ordinary histogram
(as if very fast statistical profiling sampled the pc at those
places) so that ordinary gprof can be used to analyze the times.

gmon.h:
Histogram counters need to be 4 bytes for microsecond resolutions.
They will need to be larger for the 586 clock.
The comments were vax-centric and wrong even on vaxes. Does anyone
disagree?

gprof4.c:
The standard gprof should support counters of all integral sizes
and the size of the counter should be in the gmon header. This
hack will do until then. (Use gprof4 -u to examine the results
of non-statistical profiling.)

config/*:
Non-statistical profiling is configured with `config -pp'.
`config -p' still gives ordinary profiling.

kgmon/*:
Non-statistical profiling is enabled with `kgmon -B'. `kgmon -b'
still enables ordinary profiling (and distables non-statistical
profiling) if non-statistical profiling is configured.

Remove trailing whitespace.

Added -DKERNEL and added support for kernel profiling.
Reviewed by: Bruce

Added $Id$

This commit was generated by cvs2svn to compensate for changes in r1541,
which included commits to RCS files with non-trunk default branches.

BSD 4.4 Lite Kernel Sources