into two parts - one to do the bsfl and the other to convert the result
(base 0) to ffs()-like (base 1) in inline C. This enables the optimizer
to be a lot smarter in certain cases, like where it knows that the argument
is non-zero and we want ffs(known non zero arg) - 1. This appears to
produce identical code to the old inline when the argument is unknown.
Change "void *" to "volatile TYPE *", improving type safety
and eliminating some warnings (e.g., mp_machdep.c rev 1.106).
cpufunc.h:
Eliminate setbits. As defined, it's not precisely correct;
and it's redundant. (Use atomic_set_int instead.)
ipl_funcs.c:
Use atomic_set_int instead of setbits.
systm.h:
Include atomic.h.
Reviewed by: bde
implicitly LOCK'ed instruction), so there shouldn't be any harm in making
it volatile pointer compatable for one of the users of it. It seems to
generate the same code regardless.
- %fs register is added to trapframe and saved/restored upon kernel entry/exit.
- Per-cpu pages are no longer mapped at the same virtual address.
- Each cpu now has a separate gdt selector table. A new segment selector
is added to point to per-cpu pages, per-cpu global variables are now
accessed through this new selector (%fs). The selectors in gdt table are
rearranged for cache line optimization.
- fask_vfork is now on as default for both UP and SMP.
- Some aio code cleanup.
Reviewed by: Alan Cox <alc@cs.rice.edu>
John Dyson <dyson@iquest.net>
Julian Elischer <julian@whistel.com>
Bruce Evans <bde@zeta.org.au>
David Greenman <dg@root.com>
just to ensure 32-bit variables. Doing so broke and/or pessimized
i386's with 64-bit longs (unnecessary use of 64-bit variables
caused remarkably few problems in C code, but the inline asm here
tended to fail because there are no 64-bit registers). Since the
interfaces here are very machine-dependent and shouldn't be used
outside of the kernel, use a standard types of "known" width instead
of fixed-width types.
Changed all quad_t's to u_int64_t's. quad_t isn't standard, and
using signed types for 64-bit registers was bogus (but made no
difference).
noticed some major enhancements available for UP situations. The number
of UP TLB flushes is decreased much more than significantly with these
changes. Since a TLB flush appears to cost minimally approx 80 cycles,
this is a "nice" enhancement, equiv to eliminating between 40 and 160
instructions per TLB flush.
Changes include making sure that kernel threads all use the same PTD,
and eliminate unneeded PTD switches at context switch time.
Add a simplelock to deal with disable_intr()/enable_intr() as used in UP kernel.
UP kernel expects that this is enough to guarantee exclusive access to
regions of code bracketed by these 2 functions.
Add a simplelock to bracket clock accesses in clock.c: clock_lock.
Help from: Bruce Evans <bde@zeta.org.au>
of the kernel, and also most of the dynamic parts of the kernel. Additionally,
4MB pages will be allocated for display buffers as appropriate (only.)
The 4MB support for SMP isn't complete, but doesn't interfere with operation
either.
all uses of it with the equivalent calls to setbits().
This change incidentally eliminates a problem building ELF kernels
that was caused by SETBITS.
Reviewed by: fsmp, peter
Submitted by: bde
There are various options documented in i386/conf/LINT, there is more to
come over the next few days.
The kernel should run pretty much "as before" without the options to
activate SMP mode.
There are a handful of known "loose ends" that need to be fixed, but
have been put off since the SMP kernel is in a moderately good condition
at the moment.
This commit is the result of the tinkering and testing over the last 14
months by many people. A special thanks to Steve Passe for implementing
the APIC code!
supports All Cyrix CPUs, IBM Blue Lightning CPU and NexGen (now AMD)
Nx586 CPU, and initialize special registers of Cyrix CPU and msr of
IBM Blue Lightning CPU.
If revision of Cyrix 6x86 CPU < 2.7, CPU cache is enabled in
write-through mode. This can be disabled by kernel configuration
options.
Reviewed by: Bruce Evans <bde@freebsd.org> and
Jordan K. Hubbard <jkh@freebsd.org>
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.
dependent operation, and not really a correct name. invltlb and invlpg
are more descriptive, and in the case of invlpg, a real opcode.
Additionally, fix the tlb management code for 386 machines.
comparisons in the inb() and outb() macros. I decided that int args
are OK here. Any type that can hold a u_int16_t without overflow
is correct, and 32-bit types are optimal.
Introduced a few tens of warnings (100 in LINT) for use of pessimized
(short) types for the port arg. Only a few drivers are affected by
this. u_short pessimizations aren't detected.
Added `__extension__' before the statement-expression in inb() so
that it can be compiled without warnings by gcc -pedantic.
(1) Add PC98 support to apm_bios.h and ns16550.h, remove pc98/pc98/ic
(2) Move PC98 specific code out of cpufunc.h (to pc98.h)
(3) Let the boot subtrees look more alike
Submitted by: The FreeBSD(98) Development Team
<freebsd98-hackers@jp.freebsd.org>
All new code is "#ifdef PC98"ed so this should make no difference to
PC/AT (and its clones) users.
Ok'd by: core
Submitted by: FreeBSD(98) development team
Always delay using one inb(0x84) after each i/o in rtcin() - don't
do this conditional on the bogus option DUMMY_NOPS not being defined.
If you want an optionally slightly faster rtcin() again, then inline
it and use a better named option or sysctl variable. It only needs
to be fast in rtcintr().
(This code is as yet untested; to come after man page is written.)
This also adds inlines to cpufunc.h for the RDTSC, RDMSR, WRMSR, and RDPMC
instructions. The user-mode interface is via a subdevice of mem.c;
there is also a kernel-size interface which might be used to aid
profiling.
bzero.
Deprecated blkclr (removed it).
Removed some old cruft from cpufunc.h.
The optimized bzero was submitted by Torbjorn Granlund <tege@matematik.su.se>
The kernel adaption and other changes by me.
overflows.
It sure would be nice if there was an unmapped page between the PCB and
the stack (and that the size of the stack was configurable!). With the
way things are now, the PCB will get clobbered before the double fault
handler gets control, making somewhat of a mess of things. Despite this,
it is still fairly easy to poke around in the overflowed stack to figure
out the cause.
