Commit Graph

155 Commits

Author SHA1 Message Date
John Baldwin
ba228f6d96 - Split out the support for per-CPU data from the SMP code. UP kernels
have per-CPU data and gdb on the i386 at least needs access to it.
- Clean up includes in kern_idle.c and subr_smp.c.

Reviewed by:	jake
2001-05-10 17:45:49 +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
242d02a13f Make the ap_boot_mtx mutex static. 2001-04-20 01:09:05 +00:00
John Baldwin
abd9053ee4 Blow away the panic mutex in favor of using a single atomic_cmpset() on a
panic_cpu shared variable.  I used a simple atomic operation here instead
of a spin lock as it seemed to be excessive overhead.  Also, this can avoid
recursive panics if, for example, witness is broken.
2001-04-17 04:18:08 +00:00
John Baldwin
2fea957dc5 Rename the IPI API from smp_ipi_* to ipi_* since the smp_ prefix is just
"redundant noise" and to match the IPI constant namespace (IPI_*).

Requested by:	bde
2001-04-11 17:06:02 +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
John Baldwin
6a0fa9a023 Add an MI API for sending IPI's. I used the same API present on the alpha
because:
 - it used a better namespace (smp_ipi_* rather than *_ipi),
 - it used better constant names for the IPI's (IPI_* rather than
   X*_OFFSET), and
 - this API also somewhat exists for both alpha and ia64 already.
2001-04-10 21:04:32 +00:00
John Baldwin
192846463a Rework the witness code to work with sx locks as well as mutexes.
- Introduce lock classes and lock objects.  Each lock class specifies a
  name and set of flags (or properties) shared by all locks of a given
  type.  Currently there are three lock classes: spin mutexes, sleep
  mutexes, and sx locks.  A lock object specifies properties of an
  additional lock along with a lock name and all of the extra stuff needed
  to make witness work with a given lock.  This abstract lock stuff is
  defined in sys/lock.h.  The lockmgr constants, types, and prototypes have
  been moved to sys/lockmgr.h.  For temporary backwards compatability,
  sys/lock.h includes sys/lockmgr.h.
- Replace proc->p_spinlocks with a per-CPU list, PCPU(spinlocks), of spin
  locks held.  By making this per-cpu, we do not have to jump through
  magic hoops to deal with sched_lock changing ownership during context
  switches.
- Replace proc->p_heldmtx, formerly a list of held sleep mutexes, with
  proc->p_sleeplocks, which is a list of held sleep locks including sleep
  mutexes and sx locks.
- Add helper macros for logging lock events via the KTR_LOCK KTR logging
  level so that the log messages are consistent.
- Add some new flags that can be passed to mtx_init():
  - MTX_NOWITNESS - specifies that this lock should be ignored by witness.
    This is used for the mutex that blocks a sx lock for example.
  - MTX_QUIET - this is not new, but you can pass this to mtx_init() now
    and no events will be logged for this lock, so that one doesn't have
    to change all the individual mtx_lock/unlock() operations.
- All lock objects maintain an initialized flag.  Use this flag to export
  a mtx_initialized() macro that can be safely called from drivers.  Also,
  we on longer walk the all_mtx list if MUTEX_DEBUG is defined as witness
  performs the corresponding checks using the initialized flag.
- The lock order reversal messages have been improved to output slightly
  more accurate file and line numbers.
2001-03-28 09:03:24 +00:00
Peter Wemm
50e2347e68 Kill the 4MB kernel limit dead. [I hope :-)].
For UP, we were using $tmp_stk as a stack from the data section.  If the
kernel text section grew beyond ~3MB, the data section would be pushed
beyond the temporary 4MB P==V mapping.  This would cause the trampoline
up to high memory to fault.  The hack workaround I did was to use all of
the page table pages that we already have while preparing the initial
P==V mapping, instead of just the first one.
For SMP, the AP bootstrap process suffered the same sort of problem and
got the same treatment.

MFC candidate - this breaks on 4.x just the same..

Thanks to:	Richard Todd <rmtodd@ichotolot.servalan.com>
2001-03-15 05:10:06 +00:00
Peter Wemm
f1532aadee Activate USER_LDT by default. The new thread libraries are going to
depend on this.  The linux ABI emulator tries to use it for some linux
binaries too.  VM86 had a bigger cost than this and it was made default
a while ago.

Reviewed by:	jhb, imp
2001-02-23 01:25:02 +00:00
John Baldwin
a91fe908db Woops, remove an obsolete reference to gd_cpu_lockid. 2001-02-09 16:13:57 +00:00
Bosko Milekic
9ed346bab0 Change and clean the mutex lock interface.
mtx_enter(lock, type) becomes:

mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks)
mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized)

similarily, for releasing a lock, we now have:

mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN.
We change the caller interface for the two different types of locks
because the semantics are entirely different for each case, and this
makes it explicitly clear and, at the same time, it rids us of the
extra `type' argument.

The enter->lock and exit->unlock change has been made with the idea
that we're "locking data" and not "entering locked code" in mind.

Further, remove all additional "flags" previously passed to the
lock acquire/release routines with the exception of two:

MTX_QUIET and MTX_NOSWITCH

The functionality of these flags is preserved and they can be passed
to the lock/unlock routines by calling the corresponding wrappers:

mtx_{lock, unlock}_flags(lock, flag(s)) and
mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN
locks, respectively.

Re-inline some lock acq/rel code; in the sleep lock case, we only
inline the _obtain_lock()s in order to ensure that the inlined code
fits into a cache line. In the spin lock case, we inline recursion and
actually only perform a function call if we need to spin. This change
has been made with the idea that we generally tend to avoid spin locks
and that also the spin locks that we do have and are heavily used
(i.e. sched_lock) do recurse, and therefore in an effort to reduce
function call overhead for some architectures (such as alpha), we
inline recursion for this case.

Create a new malloc type for the witness code and retire from using
the M_DEV type. The new type is called M_WITNESS and is only declared
if WITNESS is enabled.

Begin cleaning up some machdep/mutex.h code - specifically updated the
"optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN
and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently
need those.

Finally, caught up to the interface changes in all sys code.

Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
Peter Wemm
aa0b4c590f Remove some leftovers from the CMAP* stuff in globaldata and the
BSP and AP startup.
2001-01-30 04:02:28 +00:00
Bosko Milekic
84e11fbc2e Move the setting of curproc to idleproc up earlier in ap_init(). The
problem is that a mutex lock, prior to this change, is acquired before
the curproc is set to idleproc, so we mess ourselves up by calling
the mutex lock routine with curproc == NULL.

Moving it up after the aps_ready spin-wait has us hopefully setting it
after idleproc is setup.

Solved by: jake (the allmighty) :-)
2001-01-28 03:41:01 +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
Jason Evans
1b367556b5 Convert all simplelocks to mutexes and remove the simplelock implementations. 2001-01-24 12:35:55 +00:00
John Baldwin
4cbdef8448 - Relocate portions of this file to get it into an order closer to that of
the alpha mp_machdep.c.
- Proc locking.
- Catch up to the P_FOO -> PS_FOO proc flags changes.
- Stick ap_init()'s prototype with the other prototypes.
- Remove the Xforwardirq IPI.
- Remove unused simplelocks.
- Don't try to psignal() from forward_statclock(), but set the appropriate
  signal pending flag in p_sflag instead.
- Add in KTR_SMP tracepoints for various SMP functions.   (Brought over
  from the alpha port)
2001-01-24 09:48:52 +00:00
Jake Burkholder
a448b62ac9 Make intr_nesting_level per-process, rather than per-cpu. Setup
interrupt threads to run with it always >= 1, so that malloc can
detect M_WAITOK from "interrupt" context.  This is also necessary
in order to context switch from sched_ithd() directly.

Reviewed By:	peter
2001-01-21 19:25:07 +00:00
Peter Wemm
654c30a008 Remove APIC_INTR_DIAGNOSTIC - this has been disabled for some time now.
Remove some leftovers of removed SMP options.
2001-01-21 07:54:10 +00:00
Jake Burkholder
3e899e1063 Remove the per-cpu pages used for copy and zero-ing pages of memory
for SMP; just use the same ones as UP.  These weren't used without
holding Giant anyway, and the routines that use them would have to
be protected from pre-emption to avoid migrating cpus.
2001-01-21 06:50:03 +00:00
Peter Wemm
f7b6e45d5b apic_itrace_splz[] is unused 2001-01-19 10:48:35 +00:00
John Baldwin
dcfc09d931 Protect p_stat and p_oncpu with sched_lock in forward_signal(). 2001-01-18 08:19:25 +00:00
Jake Burkholder
063415120b Change return ??? to return -1 in some #if 0'ed code. 2001-01-12 08:24:25 +00:00
Jake Burkholder
ef73ae4b0c Use PCPU_GET, PCPU_PTR and PCPU_SET to access all per-cpu variables
other then curproc.
2001-01-10 04:43:51 +00:00
Jake Burkholder
bb5c0622b7 Fix a warning. The type of globaldata.gd_prvspace has changed. 2001-01-08 15:25:45 +00:00
Peter Wemm
4366ac52ad This is kind of a nasty hack, but it appears to solve the Compaq DL360
SMP problem.  Compaq, in their infinite wisdom, forgot to put the IO apic
intpin #0 connection to the 8259 PIC into the mptable.  This hack is to
look and see if intpin #0 has *no* table entry and adds a fake ExtInt
entry for the remap routines to use.  isa/clock.c will still test the
interrupts.  This entry is only ever used on an already broken system.
2000-12-06 03:47:14 +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
John Baldwin
8d9888d37a Don't wait forever for CPUs to stop or restart. Instead, give up after a
timeout.  If DIAGNOSTIC is turned on, then display a message to the console
with a map of which CPUs failed to stop or restart.  This gives an SMP box
at least a fighting chance of getting into DDB if one of the other CPUs has
interrupts disabled.
2000-11-28 23:52:36 +00:00
John Baldwin
35e0e5b311 Catch up to moving headers:
- machine/ipl.h -> sys/ipl.h
- machine/mutex.h -> sys/mutex.h
2000-10-20 07:58:15 +00:00
John Baldwin
6c56727456 - Change fast interrupts on x86 to push a full interrupt frame and to
return through doreti to handle ast's.  This is necessary for the
  clock interrupts to work properly.
- Change the clock interrupts on the x86 to be fast instead of threaded.
  This is needed because both hardclock() and statclock() need to run in
  the context of the current process, not in a separate thread context.
- Kill the prevproc hack as it is no longer needed.
- We really need Giant when we call psignal(), but we don't want to block
  during the clock interrupt.  Instead, use two p_flag's in the proc struct
  to mark the current process as having a pending SIGVTALRM or a SIGPROF
  and let them be delivered during ast() when hardclock() has finished
  running.
- Remove CLKF_BASEPRI, which was #ifdef'd out on the x86 anyways.  It was
  broken on the x86 if it was turned on since cpl is gone.  It's only use
  was to bogusly run softclock() directly during hardclock() rather than
  scheduling an SWI.
- Remove the COM_LOCK simplelock and replace it with a clock_lock spin
  mutex.  Since the spin mutex already handles disabling/restoring
  interrupts appropriately, this also lets us axe all the *_intr() fu.
- Back out the hacks in the APIC_IO x86 cpu_initclocks() code to use
  temporary fast interrupts for the APIC trial.
- Add two new process flags P_ALRMPEND and P_PROFPEND to mark the pending
  signals in hardclock() that are to be delivered in ast().

Submitted by:	jakeb (making statclock safe in a fast interrupt)
Submitted by:	cp (concept of delaying signals until ast())
2000-10-06 02:20:21 +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
John Baldwin
77044cb6d9 Clean up process accounting some more. Unfortunately, it is still not
quite right on i386 as the CPU who runs statclock() doesn't have a valid
clockframe to calculate statistics with.
2000-09-12 18:57:59 +00:00
John Baldwin
b162b45509 When doing statistics for statclock on other CPU's, use the other CPUs'
idleproc pointers instead of our own for comparisons.

Submitted by:	tegge
2000-09-11 04:10:29 +00:00
John Baldwin
1baab78f9e Remove an unneeded extern declaration of cp_time. 2000-09-08 20:18:29 +00:00
Jake Burkholder
4ef34f39ec Really fix USER_LDT. (Don't use currentldt as an L-value.) 2000-09-08 03:36:09 +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
Peter Wemm
37b087a645 Clean up some low level bootstrap code:
- stop using the evil 'struct trapframe' argument for mi_startup()
  (formerly main()).  There are much better ways of doing it.
- do not use prepare_usermode() - setregs() in execve() will do it
  all for us as long as the p_md.md_regs pointer is set.  (which is
  now done in machdep.c rather than init_main.c.  The Alpha port did it
  this way all along and is much cleaner).
- collect all the magic %cr0 etc register settings into one place and
  have the AP's call that instead of using magic numbers (!!) that keep
  changing over and over again.
- Make it safe to call kthread_create() earlier, including during the
  device probe sequence.  It doesn't need the callback mechanism that
  NetBSD's version uses.
- kthreads created this way are root-less as they exist before the root
  filesystem is mounted.  init(1) is set up so that it aquires the root
  pointers prior to running.  If other kthreads want filesystem acccess
  we can make this code more generic.
- set all threads start times once we have decided what time it is.
- init uses a trampoline rather than the evil prepare_usermode() hack.
- kern_descrip.c has a couple of tweaks to deal with forking when there
  is no rootdir or cwd etc.
- adjust the early SYSINIT() sequence so that a few prereqisites are in
  place. eg: make sure the run queue is initialized before doing forks.

With this, the USB code can easily create a kthread to do the device
tree discovery.  (I have tested it, it works nicely).

There are still some open issues before this is truely useful.
- tsleep() does not like working before the clock is running.  It
  sort-of tries to spin wait, but it can do more useful things now.
- stopping a kthread in kld code at unload time is "interesting" but
  we have a solution for that.

The Alpha code needs no changes for this.  It already uses pretty much the
same strategies, but a little cleaner.
2000-08-11 09:05:12 +00:00
Tor Egge
4428d39d63 Don't skip IOAPIC id conflict detection when only one pci bus is present.
PR:		20312
Reviewed by:	Steve Roome <steve@sse0691.bri.hp.com>
2000-08-10 17:33:24 +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
36e9f877df Commit major SMP cleanups and move the BGL (big giant lock) in the
syscall path inward.  A system call may select whether it needs the MP
    lock or not (the default being that it does need it).

    A great deal of conditional SMP code for various deadended experiments
    has been removed.  'cil' and 'cml' have been removed entirely, and the
    locking around the cpl has been removed.  The conditional
    separately-locked fast-interrupt code has been removed, meaning that
    interrupts must hold the CPL now (but they pretty much had to anyway).
    Another reason for doing this is that the original separate-lock for
    interrupts just doesn't apply to the interrupt thread mechanism being
    contemplated.

    Modifications to the cpl may now ONLY occur while holding the MP
    lock.  For example, if an otherwise MP safe syscall needs to mess with
    the cpl, it must hold the MP lock for the duration and must (as usual)
    save/restore the cpl in a nested fashion.

    This is precursor work for the real meat coming later: avoiding having
    to hold the MP lock for common syscalls and I/O's and interrupt threads.
    It is expected that the spl mechanisms and new interrupt threading
    mechanisms will be able to run in tandem, allowing a slow piecemeal
    transition to occur.

    This patch should result in a moderate performance improvement due to
    the considerable amount of code that has been removed from the critical
    path, especially the simplification of the spl*() calls.  The real
    performance gains will come later.

Approved by: jkh
Reviewed by: current, bde (exception.s)
Some work taken from: luoqi's patch
2000-03-28 07:16:37 +00:00
Matthew N. Dodd
de9cfdd736 Allow SMP systems with an MCA bus to work properly.
Reviewed by:	peter
2000-01-13 09:09:02 +00:00
Luoqi Chen
5c8b298e0e Allow SMP && NCPU == 1 to work. From now on, there's no restriction on the
value of NCPU relative to the number of cpus physically present, the actual
number of cpus utilized will be the smaller of the two.
2000-01-07 08:49:25 +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
Bruce Evans
8a9d4d98b1 Moved scheduling-related code to kern_synch.c so that it is easier to fix
and extend.  The new function containing the code is named schedclock()
as in NetBSD, but it has slightly different semantics (it already handles
incrementation of p->p_cpticks, and it should handle any calling frequency).

Agreed with in principle by:	dufault
1999-11-27 12:32:27 +00:00
Tor Egge
64793e7fe2 Eliminate remaining part of incorrect PCI bus numbering sanity check on systems with more than one PCI bus. 1999-10-15 21:38:15 +00:00
Peter Wemm
01fb93b213 Zap unneeded #includes
Submitted by:	phk
1999-10-11 14:50:03 +00:00
Peter Wemm
05385ecdf7 Set up FPU state on the AP.
Tested by:	phk
1999-09-05 20:17:40 +00:00
Peter Wemm
c3aac50f28 $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
Poul-Henning Kamp
ce9edcf5b5 Merge the cons.c and cons.h to the best of my ability. alpha may or
may not compile, I can't test it.
1999-08-09 10:35:05 +00:00