Commit Graph

29 Commits

Author SHA1 Message Date
Ed Maste
05bc9aa78f mcount: tidy up ANSIfication
libc/gmon's mcount was ANSIfied in r124180, with libkern following over
a decade later, in r325988, but some minor discrepancies remained.
Update libc/gmon's mexitcount to an ANSI C function definition, and use
(void) for libkern-only functions that take no arguments.

Reported by:	bde
2018-10-20 22:39:35 +00:00
Bruce Evans
dbe3061729 Fix recent breakages of kernel profiling, mostly on i386 (high resolution
kernel profiling remains broken).

memmove() was broken using ALTENTRY().  ALTENTRY() is only different from
ENTRY() in the profiling case, and its use in that case was sort of
backwards.  The backwardness magically turned memmove() into memcpy()
instead of completely breaking it.  Only the high resolution parts of
profiling itself were broken.  Use ordinary ENTRY() for memmove().
Turn bcopy() into a tail call to memmove() to reduce complications.
This gives slightly different pessimizations and profiling lossage.
The pessimizations are minimized by not using a frame pointer() for
bcopy().

Calls to profiling functions from exception trampolines were not
relocated.  This caused crashes on the first exception.  Fix this using
function pointers.

Addresses of exception handlers in trampolines were not relocated.  This
caused unknown offsets in the profiling data.  Relocate by abusing
setidt_disp as for pmc although this is slower than necessary and
requires namespace pollution.  pmc seems to be missing some relocations.
Stack traces and lots of other things in debuggers need similar relocations.

Most user addresses were misclassified as unknown kernel addresses and
then ignored.  Treat all unknown addresses as user. Now only user
addresses in the kernel text range are significantly misclassified (as
known kernel addresses).

The ibrs functions didn't preserve enough registers.  This is the only
recent breakage on amd64.  Although these functions are written in
asm, in the profiling case they call profiling functions which are
mostly for the C ABI, so they only have to save call-used registers.
They also have to save arg and return registers in some cases and
actually save them in all cases to reduce complications.  They end up
saving all registers except %ecx on i386 and %r10 and %r11 on amd64.
Saving these is only needed for 1 caller on each of amd64 and i386.
Save them there.  This is slightly simpler.

Remove saving %ecx in handle_ibrs_exit on i386.  Both handle_ibrs_entry
and handle_ibrs_exit use %ecx, but only the latter needed to or did
save it.  But saving it there doesn't work for the profiling case.

amd64 has more automatic saving of the most common scratch registers
%rax, %rcx and %rdx (its complications for %r10 are from unusual use
of %r10 by SYSCALL).  Thus profiling of handle_ibrs_exit_rs() was not
broken, and I didn't simplify the saving by moving the saving of these
registers from it to the caller.
2018-06-02 04:25:09 +00:00
Pedro F. Giffuni
51369649b0 sys: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:43:44 +00:00
Ed Maste
4a8dea8cf9 ANSIfy sys/libkern
PR:		223641
Submitted by:	ota@j.email.ne.jp
MFC after:	1 week
2017-11-19 00:31:13 +00:00
Warner Losh
fbbd9655e5 Renumber copyright clause 4
Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.

Submitted by:	Jan Schaumann <jschauma@stevens.edu>
Pull Request:	https://github.com/freebsd/freebsd/pull/96
2017-02-28 23:42:47 +00:00
Bruce Evans
7df7fc34a3 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.
2007-06-13 06:17:48 +00:00
Marcel Moolenaar
0f2fe153bc 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
2004-08-27 19:42:35 +00:00
Warner Losh
f36cfd49ad 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
2004-04-07 20:46:16 +00:00
David E. O'Brien
ab0de15baf Use __FBSDID(). 2003-06-11 05:37:42 +00:00
Alfred Perlstein
8febc6ba17 Remove __P. 2002-03-20 02:15:46 +00:00
Peter Wemm
44c76a36f8 We do not have UPAGES following the tail end of the user VM space anymore. 2001-08-08 04:02:22 +00:00
Mark Murray
d888fc4e73 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
2001-02-11 10:44:09 +00:00
Poul-Henning Kamp
990e680b90 Fix compilation of profiled kernels by including <machine/lock.h> 2000-10-14 08:34:27 +00:00
Peter Wemm
c447342094 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.
1999-12-29 05:07:58 +00:00
Peter Wemm
c3aac50f28 $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
Bruce Evans
450e9e37dc Converted rcsid to $Id$ again. There shouldn't be any rcsids in the kernel. 1998-08-17 19:26:37 +00:00
Bruce Evans
37889b394a 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>.
1998-07-14 05:09:48 +00:00
Peter Wemm
6875d25465 Back out part 1 of the MCFH that changed $Id$ to $FreeBSD$. We are not
ready for it yet.
1997-02-22 09:48:43 +00:00
Jordan K. Hubbard
1130b656e5 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.
1997-01-14 07:20:47 +00:00
Bruce Evans
1471a79514 Unremoved used #include of <sys/systm.h> for the !GUPROF case. 1996-10-25 06:58:53 +00:00
Bruce Evans
d6b9e17eb5 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
1996-10-17 19:32:31 +00:00
Bruce Evans
1f403fcfbf 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.
1996-08-28 20:15:32 +00:00
Poul-Henning Kamp
e911eafcba removed:
CLBYTES PD_SHIFT PGSHIFT NBPG PGOFSET CLSIZELOG2 CLSIZE pdei()
        ptei() kvtopte() ptetov() ispt() ptetoav() &c &c
new:
        NPDEPG

Major macro cleanup.
1996-05-02 14:21:14 +00:00
Bruce Evans
1ae38af2be 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.
1995-12-30 07:24:13 +00:00
Bruce Evans
912e603778 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.
1995-12-29 15:30:05 +00:00
Rodney W. Grimes
9b2e535452 Remove trailing whitespace. 1995-05-30 08:16:23 +00:00
Paul Richards
03b6d659e5 Added -DKERNEL and added support for kernel profiling.
Reviewed by:	Bruce
1994-09-15 15:41:48 +00:00
David Greenman
3c4dd3568f Added $Id$ 1994-08-02 07:55:43 +00:00
Rodney W. Grimes
df8bae1de4 BSD 4.4 Lite Kernel Sources 1994-05-24 10:09:53 +00:00