Commit Graph

90 Commits

Author SHA1 Message Date
Alexander Kabaev
fa298d5ea8 Include machine/pcb.hto turn extern struct pcb stoppcbs[]; construct
into the valid C.
2007-05-19 05:01:43 +00:00
John Baldwin
4c5bec1161 Change the x86 interrupt code to use FreeBSD CPU IDs (i.e. PCPU_GET(cpuid))
rather than local APIC IDs to keep track of CPUs which can handle
interrupts.
2007-03-06 17:16:47 +00:00
John Baldwin
4ac60df584 Add a new 'pmap_invalidate_cache()' to flush the CPU caches via the
wbinvd() instruction.  This includes a new IPI so that all CPU caches on
all CPUs are flushed for the SMP case.

MFC after:	1 month
2006-05-01 21:36:47 +00:00
John Baldwin
b439e431bf Tweak how the MD code calls the fooclock() methods some. Instead of
passing a pointer to an opaque clockframe structure and requiring the
MD code to supply CLKF_FOO() macros to extract needed values out of the
opaque structure, just pass the needed values directly.  In practice this
means passing the pair (usermode, pc) to hardclock() and profclock() and
passing the boolean (usermode) to hardclock_cpu() and hardclock_process().
Other details:
- Axe clockframe and CLKF_FOO() macros on all architectures.  Basically,
  all the archs were taking a trapframe and converting it into a clockframe
  one way or another.  Now they can just extract the PC and usermode values
  directly out of the trapframe and pass it to fooclock().
- Renamed hardclock_process() to hardclock_cpu() as the latter is more
  accurate.
- On Alpha, we now run profclock() at hz (profhz == hz) rather than at
  the slower stathz.
- On Alpha, for the TurboLaser machines that don't have an 8254
  timecounter, call hardclock() directly.  This removes an extra
  conditional check from every clock interrupt on Alpha on the BSP.
  There is probably room for even further pruning here by changing Alpha
  to use the simplified timecounter we use on x86 with the lapic timer
  since we don't get interrupts from the 8254 on Alpha anyway.
- On x86, clkintr() shouldn't ever be called now unless using_lapic_timer
  is false, so add a KASSERT() to that affect and remove a condition
  to slightly optimize the non-lapic case.
- Change prototypeof  arm_handler_execute() so that it's first arg is a
  trapframe pointer rather than a void pointer for clarity.
- Use KCOUNT macro in profclock() to lookup the kernel profiling bucket.

Tested on:	alpha, amd64, arm, i386, ia64, sparc64
Reviewed by:	bde (mostly)
2005-12-22 22:16:09 +00:00
John Baldwin
333b8de537 MFi386:
- Move PUSH_FRAME and POP_FRAME to asmacros.h and use PUSH_FRAME in
  atpic entry points.
- Move PCPU_* asm macros out of the middle of the asm profiling macros.
- Pass IRQ vector argument as an int rather than void * to reduce diffs
  with i386.
- EOI the lapic in C for the lapic timer handler.
- GC unused Xcpuast function.
- Split IPI_STOP handling code of ipi_nmi_handler() out into a
  cpustop_handler() function and call it from Xcpustop rather than
  duplicating all the logic in assembly.
- Fixup the list of symbols with interrupt frames in ddb traces.
  Xatpic_fastintr* have never existed on amd64, and the lapic timer
  handler and various IPI handlers were missing.
- Use trapframe instead of intrframe for interrupt entry points (on amd64
  the interrupt vector was already a separate argument, so the two frames
  were already identical) and GC intrframe.

Submitted by:	peter (3)
2005-12-08 18:33:30 +00:00
John Baldwin
58553b9925 Rename the KDB_STOP_NMI kernel option to STOP_NMI and make it apply to all
IPI_STOP IPIs.
- Change the i386 and amd64 MD IPI code to send an NMI if STOP_NMI is
  enabled if an attempt is made to send an IPI_STOP IPI.  If the kernel
  option is enabled, there is also a sysctl to change the behavior at
  runtime (debug.stop_cpus_with_nmi which defaults to enabled).  This
  includes removing stop_cpus_nmi() and making ipi_nmi_selected() a
  private function for i386 and amd64.
- Fix ipi_all(), ipi_all_but_self(), and ipi_self() on i386 and amd64 to
  properly handle bitmapped IPIs as well as IPI_STOP IPIs when STOP_NMI is
  enabled.
- Fix ipi_nmi_handler() to execute the restart function on the first CPU
  that is restarted making use of atomic_readandclear() rather than
  assuming that the BSP is always included in the set of restarted CPUs.
  Also, the NMI handler didn't clear the function pointer meaning that
  subsequent stop and restarts could execute the function again.
- Define a new macro HAVE_STOPPEDPCBS on i386 and amd64 to control the use
  of stoppedpcbs[] and always enable it for i386 and amd64 instead of
  being dependent on KDB_STOP_NMI.  It works fine in both the NMI and
  non-NMI cases.
2005-10-24 21:04:19 +00:00
Doug White
fdc9713bf7 Implement an alternate method to stop CPUs when entering DDB. Normally we use
a regular IPI vector, but this vector is blocked when interrupts are disabled.
With "options KDB_STOP_NMI" and debug.kdb.stop_cpus_with_nmi set, KDB will
send an NMI to each CPU instead. The code also has a context-stuffing
feature which helps ddb extract the state of processes running on the
stopped CPUs.

KDB_STOP_NMI is only useful with SMP and complains if SMP is not defined.
This feature only applies to i386 and amd64 at the moment, but could be
used on other architectures with the appropriate MD bits.

Submitted by:	ups
2005-04-30 20:01:00 +00:00
Peter Wemm
c29f1e2b3b MFi386: Bring over John's local apic timer code 2005-02-28 23:37:35 +00:00
Peter Wemm
b6e89c6d47 JumboMFi386: use bitmapped IPI handler. Update elcr and default mptable
config handler.  Tidy up various local apic initialization.
2005-01-21 06:01:20 +00:00
Warner Losh
46280ae719 Begin all license/copyright comments with /*- 2005-01-05 20:17:21 +00:00
Peter Wemm
12c1418ccf Kill the LAZYPMAP ifdefs. While they worked, they didn't do anything
to help the AMD cpus (which have a hardware tlb flush filter).  I held
off to see what the 64 bit Intel cpus did, but it doesn't seem to help
much there either.  Oh well, store it in the Attic.
2004-05-16 22:11:50 +00:00
Peter Wemm
b29fd7c4db MFi386: mp_topology(). 2004-01-28 23:51:16 +00:00
Peter Wemm
0d2a298904 Initial landing of SMP support for FreeBSD/amd64.
- This is heavily derived from John Baldwin's apic/pci cleanup on i386.
- I have completely rewritten or drastically cleaned up some other parts.
  (in particular, bootstrap)
- This is still a WIP.  It seems that there are some highly bogus bioses
  on nVidia nForce3-150 boards.  I can't stress how broken these boards
  are.  I have a workaround in mind, but right now the Asus SK8N is broken.
  The Gigabyte K8NPro (nVidia based) is also mind-numbingly hosed.
- Most of my testing has been with SCHED_ULE.  SCHED_4BSD works.
- the apic and acpi components are 'standard'.
- If you have an nVidia nForce3-150 board, you are stuck with 'device
  atpic' in addition, because they somehow managed to forget to connect the
  8254 timer to the apic, even though its in the same silicon!  ARGH!
  This directly violates the ACPI spec.
2003-11-17 08:58:16 +00:00
Peter Wemm
afa8862328 Commit MD parts of a loosely functional AMD64 port. This is based on
a heavily stripped down FreeBSD/i386 (brutally stripped down actually) to
attempt to get a stable base to start from.  There is a lot missing still.
Worth noting:
- The kernel runs at 1GB in order to cheat with the pmap code.  pmap uses
  a variation of the PAE code in order to avoid having to worry about 4
  levels of page tables yet.
- It boots in 64 bit "long mode" with a tiny trampoline embedded in the
  i386 loader.  This simplifies locore.s greatly.
- There are still quite a few fragments of i386-specific code that have
  not been translated yet, and some that I cheated and wrote dumb C
  versions of (bcopy etc).
- It has both int 0x80 for syscalls (but using registers for argument
  passing, as is native on the amd64 ABI), and the 'syscall' instruction
  for syscalls.  int 0x80 preserves all registers, 'syscall' does not.
- I have tried to minimize looking at the NetBSD code, except in a couple
  of places (eg: to find which register they use to replace the trashed
  %rcx register in the syscall instruction).  As a result, there is not a
  lot of similarity.  I did look at NetBSD a few times while debugging to
  get some ideas about what I might have done wrong in my first attempt.
2003-05-01 01:05:25 +00:00
Peter Wemm
cc66ebe2a9 Commit a partial lazy thread switch mechanism for i386. it isn't as lazy
as it could be and can do with some more cleanup.  Currently its under
options LAZY_SWITCH.  What this does is avoid %cr3 reloads for short
context switches that do not involve another user process.  ie: we can
take an interrupt, switch to a kthread and return to the user without
explicitly flushing the tlb.  However, this isn't as exciting as it could
be, the interrupt overhead is still high and too much blocks on Giant
still.  There are some debug sysctls, for stats and for an on/off switch.

The main problem with doing this has been "what if the process that you're
running on exits while we're borrowing its address space?" - in this case
we use an IPI to give it a kick when we're about to reclaim the pmap.

Its not compiled in unless you add the LAZY_SWITCH option.  I want to fix a
few more things and get some more feedback before turning it on by default.

This is NOT a replacement for Bosko's lazy interrupt stuff.  This was more
meant for the kthread case, while his was for interrupts.  Mine helps a
little for interrupts, but his helps a lot more.

The stats are enabled with options SWTCH_OPTIM_STATS - this has been a
pseudo-option for years, I just added a bunch of stuff to it.

One non-trivial change was to select a new thread before calling
cpu_switch() in the first place.  This allows us to catch the silly
case of doing a cpu_switch() to the current process.  This happens
uncomfortably often.  This simplifies a bit of the asm code in cpu_switch
(no longer have to call choosethread() in the middle).  This has been
implemented on i386 and (thanks to jake) sparc64.  The others will come
soon.  This is actually seperate to the lazy switch stuff.

Glanced at by:  jake, jhb
2003-04-02 23:53:30 +00:00
Paul Saab
87437b0b89 Nuke options HTT infavor of machdep.hlt_logical_cpus tunable/sysctl.
This keeps the logical cpu's halted in the idle loop.  By default
the logical cpu's are halted at startup.  It is also possible to
halt any cpu in the idle loop now using machdep.hlt_cpus.

Examples of how to use this:
machdep.hlt_cpus=1	halt cpu0
machdep.hlt_cpus=2	halt cpu1
machdep.hlt_cpus=4	halt cpu2
machdep.hlt_cpus=3	halt cpu0,cpu1

Reviewed by:	jhb, peter
2003-03-26 19:49:34 +00:00
Jake Burkholder
238dd3209a Split statclock into statclock and profclock, and made the method for driving
statclock based on profhz when profiling is enabled MD, since most platforms
don't use this anyway.  This removes the need for statclock_process, whose
only purpose was to subdivide profhz, and gets the profiling clock running
outside of sched_lock on platforms that implement suswintr.
Also changed the interface for starting and stopping the profiling clock to
do just that, instead of changing the rate of statclock, since they can now
be separate.

Reviewed by:	jhb, tmm
Tested on:	i386, sparc64
2003-02-03 17:53:15 +00:00
Jim Pirzyk
b2eb172cc3 Add the !define(COMPILING_LINT)
pass the pointy hat...

Requested by: Juli Mallett <jmallett@FreeBSD.org>
2002-10-17 18:17:28 +00:00
Jim Pirzyk
c8c1cf0ca7 put an #error directive when SMP and CPU_DISABLE_CMPXCHG are set
together.

Requested by: Lars Eggart <larse@isi.edu>
Enlighted how to do it by: John Baldwin <jhb@freebsd.org>
2002-10-17 05:51:36 +00:00
Peter Wemm
f1b665c8fe Revive backed out pmap related changes from Feb 2002. The highlights are:
- It actually works this time, honest!
- Fine grained TLB shootdowns for SMP on i386.  IPI's are very expensive,
  so try and optimize things where possible.
- Introduce ranged shootdowns that can be done as a single IPI.
- PG_G support for i386
- Specific-cpu targeted shootdowns.  For example, there is no sense in
  globally purging the TLB cache for where we are stealing a page from
  the local unshared process on the local cpu.  Use pm_active to track
  this.
- Add some instrumentation for the tlb shootdown code.
- Rip out SMP code from <machine/cpufunc.h>
- Try and fix some very bogus PG_G and PG_PS interactions that were bad
  enough to cause vm86 bios calls to break.  vm86 depended on our existing
  bugs and this was the cause of the VESA panics last time.
- Fix the silly one-line error that caused the 'panic: bad pte' last time.
- Fix a couple of other silly one-line errors that should have caused more
  pain than they did.

Some more work is needed:
- pmap_{zero,copy}_page[_idle].  These can be done without IPI's if we
  have a hook in cpu_switch.
- The IPI handlers need some cleanup.  I have a bogus %ds load that can
  be avoided.
- APTD handling is rather bogus and appears to be a large source of
  global TLB IPI shootdowns for no really good reason.

I see speedups of between 1.5% and ~4% on buildworlds in a while 1 loop.
I expect to see a bigger difference when there is significant pageout
activity or the system otherwise has memory shortages.

I have backed out a few optimizations that I had been using over the last
few days in order to be a little more conservative.  I'll revisit these
again over the next few days as the dust settles.

New option:  DISABLE_PG_G - In case I missed something.
2002-07-12 07:56:11 +00:00
Bruce Evans
809dbbc99b Fixed some style bugs in the removal of __P(()). The main ones were
not removing tabs before "__P((", and not outdenting continuation lines
to preserve non-KNF lining up of code with parentheses.  Switch to KNF
formatting and/or rewrap the whole prototype in some cases.
2002-03-23 15:09:35 +00:00
Alfred Perlstein
b63dc6ad47 Remove __P. 2002-03-20 05:48:58 +00:00
Peter Wemm
d1693e1701 Back out all the pmap related stuff I've touched over the last few days.
There is some unresolved badness that has been eluding me, particularly
affecting uniprocessor kernels.  Turning off PG_G helped (which is a bad
sign) but didn't solve it entirely.  Userland programs still crashed.
2002-02-27 09:51:33 +00:00
Peter Wemm
6bd95d70db Work-in-progress commit syncing up pmap cleanups that I have been working
on for a while:
- fine grained TLB shootdown for SMP on i386
- ranged TLB shootdowns.. eg: specify a range of pages to shoot down with
  a single IPI, since the IPI is very expensive.  Adjust some callers
  that used to trigger this inside tight loops to do a ranged shootdown
  at the end instead.
- PG_G support for SMP on i386 (options ENABLE_PG_G)
- defer PG_G activation till after we decide what we are going to do with
  PSE and the 4MB pages at the start of the kernel.  This should solve
  some rumored strangeness about stale PG_G entries getting stuck
  underneath the 4MB pages.
- add some instrumentation for the fine TLB shootdown
- convert some asm instruction wrappers from functions to inlines.  gcc
  seems to do a fair bit better with this.
- [temporarily!] pessimize the tlb shootdown IPI handlers.  I will fix
  this again shortly.

This has been working fairly well for me for a while, but I have tweaked
it again prior to commit since my last major testing round.  The only
outstanding problem that I know of is PG_G related, which is why there
is an option for it (not on by default for SMP).  I have seen a world
speedups by a few percent (as much as 4 or 5% in one case) but I have
*not* accurately measured this - I am a bit sceptical of these numbers.
2002-02-25 23:49:51 +00:00
John Baldwin
1ecf0d56c8 Small cleanups to the SMP code:
- Axe inlvtlb_ok as it was completely redundant with smp_active.
- Remove references to non-existent variable and non-existent file
  in i386/include/smp.h.
- Don't perform initializations local to each CPU while holding the
  ap boot lock on i386 while an AP bootstraps itself.
- Reorganize the AP startup code some to unify the latter half of the
  functions to bring an AP up.  Eventually this might be broken out into
  a MI function in subr_smp.c.
2001-12-17 23:14:35 +00:00
John Baldwin
6caa8a1501 Overhaul of the SMP code. Several portions of the SMP kernel support have
been made machine independent and various other adjustments have been made
to support Alpha SMP.

- It splits the per-process portions of hardclock() and statclock() off
  into hardclock_process() and statclock_process() respectively.  hardclock()
  and statclock() call the *_process() functions for the current process so
  that UP systems will run as before.  For SMP systems, it is simply necessary
  to ensure that all other processors execute the *_process() functions when the
  main clock functions are triggered on one CPU by an interrupt.  For the alpha
  4100, clock interrupts are delievered in a staggered broadcast fashion, so
  we simply call hardclock/statclock on the boot CPU and call the *_process()
  functions on the secondaries.  For x86, we call statclock and hardclock as
  usual and then call forward_hardclock/statclock in the MD code to send an IPI
  to cause the AP's to execute forwared_hardclock/statclock which then call the
  *_process() functions.
- forward_signal() and forward_roundrobin() have been reworked to be MI and to
  involve less hackery.  Now the cpu doing the forward sets any flags, etc. and
  sends a very simple IPI_AST to the other cpu(s).  AST IPIs now just basically
  return so that they can execute ast() and don't bother with setting the
  astpending or needresched flags themselves.  This also removes the loop in
  forward_signal() as sched_lock closes the race condition that the loop worked
  around.
- need_resched(), resched_wanted() and clear_resched() have been changed to take
  a process to act on rather than assuming curproc so that they can be used to
  implement forward_roundrobin() as described above.
- Various other SMP variables have been moved to a MI subr_smp.c and a new
  header sys/smp.h declares MI SMP variables and API's.   The IPI API's from
  machine/ipl.h have moved to machine/smp.h which is included by sys/smp.h.
- The globaldata_register() and globaldata_find() functions as well as the
  SLIST of globaldata structures has become MI and moved into subr_smp.c.
  Also, the globaldata list is only available if SMP support is compiled in.

Reviewed by:	jake, peter
Looked over by:	eivind
2001-04-27 19:28:25 +00:00
John Baldwin
ca7ef17c08 Remove the BETTER_CLOCK #ifdef's. The code is on by default and is here
to stay for the foreseeable future.

OK'd by:	peter (the idea)
2001-04-10 21:34:13 +00:00
Tor Egge
48bed92485 Defer assignment of low level interrupt handlers for PCI interrupts
described in the MP table until something asks for the interrupt number
later on.
2001-01-28 01:07:54 +00:00
Peter Wemm
a263238c86 Move io_apic_{read,write} from apic_ipl.s (where they do not belong) into
mpapic.c.  This gives us the benefit of C type checking.  These functions
are not called in any critical paths and are not used by the interrupt
routines.
2000-12-06 01:04:02 +00:00
Peter Wemm
9a18987b73 GC unused assembler function apic_eoi() 2000-12-06 00:38:04 +00:00
Peter Wemm
5ee171d264 Cleanup some leftover lint from the old interrupt system.
Also, while here, run up to 32 interrupt sources on APIC systems.
Normalize INTREN/INTRDIS so they are the same on both UP and SMP systems
rather than sometimes a macro, and sometimes a function.

Reviewed by:  jhb, jakeb
2000-12-04 21:15:14 +00:00
Paul Saab
92b123a002 Move MAXCPU from machine/smp.h to machine/param.h to fix breakage
with !SMP kernels.  Also, replace NCPUS with MAXCPU since they are
redundant.
2000-09-23 12:18:06 +00:00
Paul Saab
7321545f26 Remove the NCPU, NAPIC, NBUS, NINTR config options. Make NAPIC,
NBUS, NINTR dynamic and set NCPU to a maximum of 16 under SMP.

Reviewed by:	peter
2000-09-22 23:40:10 +00:00
Poul-Henning Kamp
c866ec47e3 Make LINT compile. 2000-09-16 18:55:05 +00:00
John Baldwin
746a935474 Test for both SMP and I386_CPU being set before generating an error. 2000-09-07 16:10:02 +00:00
Jason Evans
0384fff8c5 Major update to the way synchronization is done in the kernel. Highlights
include:

* Mutual exclusion is used instead of spl*().  See mutex(9).  (Note: The
  alpha port is still in transition and currently uses both.)

* Per-CPU idle processes.

* Interrupts are run in their own separate kernel threads and can be
  preempted (i386 only).

Partially contributed by:	BSDi (BSD/OS)
Submissions by (at least):	cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
Mike Smith
8ade16819d Increase the default NAPIC from 1 to 2 as a bandaid until we allocate
these dynamically (ie. typically you shouldn't have to set NAPIC at all)
2000-08-18 20:09:15 +00:00
Tor Egge
e666f57c3e Be more verbose when changing APIC ID on an IO APIC.
Don't allow cpu entries in the MP table to contain APIC IDs out of range.

Don't write outside array boundaries if an IO APIC entry in the MP table
contains an APIC ID out of range.

Assign APIC IDs for all IO APICs according to section 3.6.6 in the
Intel MP spec:

  - If the current APIC ID on an IO APIC doesn't conflict with other
    IO APICs or CPUs, that APIC ID should be used.  The copy of the MP
    table must be updated if the corresponding APIC ID in the MP table
    is different.

  - If the current APIC ID was in conflict with other units, the
    corresponding APIC ID specified in the MP table is checked for conflict.

  - If a conflict is still found then fall back to using a new unique ID.
    The copy of the MP table must be updated.

  - IDs out of range is considered to be in conflict.

During these operations, the IO_TO_ID array cannot be used, since any
conflict would have caused information loss.  The array is then corrected,
since all APIC ID conflicts should have been resolved.

PR:	20312, 18919
2000-08-06 00:04:03 +00:00
Mike Smith
c3c50c4e3a Further fixes for multiple-IO-APIC systems from Tor Egge:
Further experimentation showed that some Dell 2450 machines with the
prevention kludge installed still got T_RESERVED traps.  CPU interrupt
vector 0x7A was observed to be triggered.  This might have been the
bitwise OR of two different vectors sent from each of the IOAPICs at
the same time.

	IOAPIC #0: 0x68 --> irq 8: RTC timer interrupt
	IOAPIC #1: 0x32 --> irq 18: scsi host adapter or network interface
		   ----
		   0x7a --> T_RESERVED

Both IOAPICs had ID 0.

Appendix B.3 in the MP spec indicates that the operating system is
responsible for assigning unique IDs to the IOAPICs.

The enclosed patch programs the IOAPIC IDs according to the IOAPIC
entries in the MP table.

Submitted by:	tegge
2000-05-31 21:37:28 +00:00
Matthew Dillon
db6a426158 The SMP cleanup commit broke UP compiles. Make UP compiles work again. 2000-03-28 18:06:49 +00:00
Tor Egge
82916a1126 ISA device drivers use the ISA source interrupt number in locations where
the low level interrupt handler number should be used.  Change
setup_apic_irq_mapping() to allocate low level interrupt handler X (Xintr${X})
for any ISA interrupt X mentioned in the MP table.

Remove an assumption in the driver for the system clock (clock.c) that
interrupts mentioned in the MP table as delivered to IOAPIC #0 intpin Y
is handled by low level interrupt handler Y (Xintr${Y}) but don't assume
that low level interrupt handler 0 (Xintr0) is used.

Don't allocate two low level interrupt handlers for the system clock.
Reviewed by:	NOKUBI Hirotaka <hnokubi@yyy.or.jp>
2000-01-04 22:24:59 +00:00
Peter Wemm
664a31e496 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 04:46:21 +00:00
Matt Jacob
f327fe4c57 Fix from Tor so that if we enter the debugger in the tristate going to
SMP (other CPUs stopped but SMP mode not really started).

Obtained from:Tor.Egge@fast.no
1999-09-25 18:36:31 +00:00
Peter Wemm
c3aac50f28 $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
Mike Smith
91fe3dc1e1 Implement an all-CPU shootdown-style rendezvous facility. This allows
the caller to specify a function to be guarded between an entry and exit
barrier, as well as pre- and post-barrier functions.

The primary use for this function is synchronised update of per-cpu private
data.  The implementation is almost (but not quite) MI; with a better
mechanism for masking per-CPU interrupts it could probably be hoisted.

Reviewed by:	peter (partially)
1999-07-20 06:52:35 +00:00
Luoqi Chen
5206bca10a Enable vmspace sharing on SMP. Major changes are,
- %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>
1999-04-28 01:04:33 +00:00
Tor Egge
572d053e17 Maintain a mapping from irq number to (ioapic number, int pin) tuple,
and use this when masking/unmasking interrupts.

Maintain a mapping from (iopaic number, int pin) tuple to irq number,
and use this when configuring devices and programming the ioapics.

Previous code assumed that irq number was equal to int pin number, and
that the ioapic number was 0.

Don't let an AP enter _cpu_switch before all local apics are initialized.
1998-09-06 22:41:42 +00:00
Tor Egge
2f1e70693d Add forwarding of roundrobin to other cpus. This gives a more regular
update of cpu usage as shown by top when one process is cpu bound
(no system calls) while the system is otherwise idle (except for top).

Don't attempt to switch to the BSP in boot().  If the system was idle when
an interrupt caused a panic, this won't work.  Instead, switch to the BSP
in cpu_reset.

Remove some spurious forward_statclock/forward_hardclock warnings.
1998-05-17 22:12:14 +00:00
Tor Egge
5758c2de94 Add two workarounds for broken MP tables:
- Attempt to handle PCI devices where the interrupt is
	  an ISA/EISA interrupt according to the mp table.

	- Attempt to handle multiple IO APIC pins connected to
	  the same PCI or ISA/EISA interrupt source.  Print a
	  warning if this happens, since performance is suboptimal.
	  This workaround is only used for PCI devices.

With these two workarounds, the -SMP kernel is capable of running on
my Asus P/I-P65UP5 motherboard when version 1.4 of the MP table is disabled.
1998-04-01 21:07:37 +00:00
Tor Egge
300e9a7696 Declare some variables modified by interrupt handlers as volatile. 1998-04-01 20:38:28 +00:00