Commit Graph

695 Commits

Author SHA1 Message Date
John Baldwin
8bd57f8fc2 Remove unneeded includes of sys/ipl.h and machine/ipl.h. 2001-05-15 23:22:29 +00:00
John Baldwin
df4d012b9a - Use sched_lock and critical regions to ensure that LDT updates are thread
safe from preemption and concurrent access to the LDT.
- Move the prototype for i386_extend_pcb() to <machine/pcb_ext.h>.

Reviewed by:	silence on -hackers
2001-05-10 17:03:03 +00:00
Mark Murray
fb919e4d5a Undo part of the tangle of having sys/lock.h and sys/mutex.h included in
other "system" header files.

Also help the deprecation of lockmgr.h by making it a sub-include of
sys/lock.h and removing sys/lockmgr.h form kernel .c files.

Sort sys/*.h includes where possible in affected files.

OK'ed by:	bde (with reservations)
2001-05-01 08:13:21 +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
Warner Losh
a5e25da40d Back out 1.103. It wasn't approved by the owner of the file and
introduced style bugs.

Submited by: bde
2001-04-18 20:57:43 +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
5f76d89870 Remove constants defining the bitmasks of the old giant kernel lock. 2001-04-10 22:22:01 +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
ae60f36f19 Axe the per-cpu variable witness_spin_check as it was replaced by the
per-cpu spinlocks list.
2001-04-06 07:20:27 +00:00
Warner Losh
884c6f61f4 De __P() while I'm here. Done as a separate commit since it is just
stylistic.

# Yes, this break K&R, but this file already used so many gcc extensions
# keeping K&R support seemed too anachronistic for me.

Didn't fix the bug where functions that can only be used in the kernel
are exported to userland.
2001-04-03 18:50:55 +00:00
Warner Losh
29d5de8ad0 Make this file C++ safe. It defines many useful functions (inb, outb)
that people use from userland in C++ programs.  I've had this in my
tree for ages and just got bit by it not being in the real tree again.

This is a MFC candidate.
2001-04-03 18:19:49 +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
John Baldwin
6283b7d01b - Switch from using save/disable/restore_intr to using critical_enter/exit
and change the u_int mtx_saveintr member of struct mtx to a critical_t
  mtx_savecrit.
- On the alpha we no longer need a custom _get_spin_lock() macro to avoid
  an extra PAL call, so remove it.
- Partially fix using mutexes with WITNESS in modules.  Change all the
  _mtx_{un,}lock_{spin,}_flags() macros to accept explicit file and line
  parameters and rename them to use a prefix of two underscores.  Inside
  of kern_mutex.c, generate wrapper functions for
  _mtx_{un,}lock_{spin,}_flags() (only using a prefix of one underscore)
  that are called from modules.  The macros mtx_{un,}lock_{spin,}_flags()
  are mapped to the __mtx_* macros inside of the kernel to inline the
  usual case of mutex operations and map to the internal _mtx_* functions
  in the module case so that modules will use WITNESS and KTR logging if
  the kernel is compiled with support for it.
2001-03-28 02:40:47 +00:00
John Baldwin
034dc442ad - Add the new critical_t type used to save state inside of critical
sections.
- Add implementations of the critical_enter() and critical_exit() functions
  and remove restore_intr() and save_intr().
- Remove the somewhat bogus disable_intr() and enable_intr() functions on
  the alpha as the alpha actually uses a priority level and not simple bit
  flag on the CPU.
2001-03-28 02:31:54 +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
John Baldwin
5db078a9be Fix mtx_legal2block. The only time that it is bad to block on a mutex is
if we hold a spin mutex, since we can trivially get into deadlocks if we
start switching out of processes that hold spinlocks.  Checking to see if
interrupts were disabled was a sort of cheap way of doing this since most
of the time interrupts were only disabled when holding a spin lock.  At
least on the i386.  To fix this properly, use a per-process counter
p_spinlocks that counts the number of spin locks currently held, and
instead of checking to see if interrupts are disabled in the witness code,
check to see if we hold any spin locks.  Since child processes always
start up with the sched lock magically held in fork_exit(), we initialize
p_spinlocks to 1 for child processes.  Note that proc0 doesn't go through
fork_exit(), so it starts with no spin locks held.

Consulting from:	cp
2001-03-09 07:24:17 +00:00
Matthew N. Dodd
c7411c02f5 version 1.7 made some changes to correct problems identifed by compiling
with egcs-1.1.1.  bus_space_write_multi_2() had an extra operation that
should have been removed.

Remove it.

This fixes the panic when bus_space_write_multi_2() is used.

Obtained from:		jake
2001-03-02 05:33:53 +00:00
Peter Wemm
5107b058bc Always use the ELF naming after the demise of asnames.h. 2001-02-25 07:23:03 +00:00
Jake Burkholder
02318dac2c Remove the leading underscore from all symbols defined in x86 asm
and used in C or vice versa.  The elf compiler uses the same names
for both.  Remove asnames.h with great prejudice; it has served its
purpose.

Note that this does not affect the ability to generate an aout kernel
due to gcc's -mno-underscores option.

moral support from:	peter, jhb
2001-02-25 06:29:04 +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
0246af0995 GC unused and now obsolete assertion macros. 2001-02-22 15:45:49 +00:00
John Baldwin
5813dc03bd - Don't call clear_resched() in userret(), instead, clear the resched flag
in mi_switch() just before calling cpu_switch() so that the first switch
  after a resched request will satisfy the request.
- While I'm at it, move a few things into mi_switch() and out of
  cpu_switch(), specifically set the p_oncpu and p_lastcpu members of
  proc in mi_switch(), and handle the sched_lock state change across a
  context switch in mi_switch().
- Since cpu_switch() no longer handles the sched_lock state change, we
  have to setup an initial state for sched_lock in fork_exit() before we
  release it.
2001-02-20 05:26:15 +00:00
Bruce Evans
0ad74739ac Removed all traces of T_ASTFLT (except for gaps where it was). It became
unused except in dead code when ast() was split off from trap().
2001-02-19 15:47:38 +00:00
Bruce Evans
866546105a Changed the aston() family to operate on a specified process instead of
always on curproc.  This is needed to implement signal delivery properly
(see a future log message for kern_sig.c).

Debogotified the definition of aston().  aston() was defined in terms
of signotify() (perhaps because only the latter already operated on
a specified process), but aston() is the primitive.

Similar changes are needed in the ia64 versions of cpu.h and trap.c.
I didn't make them because the ia64 is missing the prerequisite changes
to make astpending and need_resched per-process and those changes are
too large to make without testing.
2001-02-19 04:15:59 +00:00
Bruce Evans
12a586bbda Fixed style bugs in clock.c rev.1.164 and cpu.h rev.1.52-1.53 -- declare
tsc_present in the right places (together with other variables of the
same linkage), and don't use messy ifdefs just to avoid exporting it in
some cases.
2001-02-19 03:00:34 +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
John Baldwin
142ba5f3d7 - Make astpending and need_resched process attributes rather than CPU
attributes.  This is needed for AST's to be properly posted in a preemptive
  kernel.  They are backed by two new flags in p_sflag: PS_ASTPENDING and
  PS_NEEDRESCHED.  They are still accesssed by their old macros:
  aston(), astoff(), etc.  For completeness, an astpending() macro has been
  added to check for a pending AST, and clear_resched() has been added to
  clear need_resched().
- Rename syscall2() on the x86 back to syscall() to be consistent with
  other architectures.
2001-02-10 02:20:34 +00:00
John Baldwin
e109e2b4cd Add a macro mtx_intr_enable() to alter a spin lock such that interrupts
will be enabled when it is released.
2001-02-10 02:15:18 +00:00
John Baldwin
a91fe908db Woops, remove an obsolete reference to gd_cpu_lockid. 2001-02-09 16:13:57 +00:00
John Baldwin
7f918b0230 Axe gd_cpu_lockid as it is no longer used. 2001-02-09 14:25:22 +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
5b8c74d59a - Proc locking.
- P_OWEUPC -> PS_OWEUPC.
- Remove obsolete prototype for MD fork_return().
2001-01-24 09:56:49 +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
Jason Evans
0cde2e34af Move most of sys/mutex.h into kern/kern_mutex.c, thereby making the mutex
inline functions non-inlined.  Hide parts of the mutex implementation that
should not be exposed.

Make sure that WITNESS code is not executed during boot until the mutexes
are fully initialized by SI_SUB_MUTEX (the original motivation for this
commit).

Submitted by:	peter
2001-01-21 22:34:43 +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
Jake Burkholder
87dce36809 Simplify the i386 asm MTX_{ENTER,EXIT} macros to just call the
appropriate function, rather than doing a horse-and-buggy
acquire.  They now take the mutex type as an arg and can be
used with sleep as well as spin mutexes.
2001-01-20 04:14:25 +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
John Baldwin
324fffaed1 - Sort of lie and say that %eax is an output only and not an input for the
non-386 atomic_load_acq().  %eax is an input since its value is used in
  the cmpxchg instruction, but we don't care what value it is, so setting
  it to a specific value is just wasteful.  Thus, it is being used without
  being initialized as the warning stated, but it is ok for it to be used
  because its value isn't important.  Thus, we are only sort of lying when
  we say it is an output only operand.
- Add "cc" to the clobber list for atomic_load_acq() since the cmpxchgl
  changes ZF.
2001-01-17 02:15:11 +00:00
John Baldwin
248c2e72aa Argh, disable the micro-ops again. I didn't test these adequately and
managed to lock up one of my machines in world again.

Pointy-hat to:	me
2001-01-16 04:48:38 +00:00
John Baldwin
2ccd992403 - Use "+a" instead of "=&a" for several constraints. This should fix
compiling errors where gcc would run out of registers.
- Add "cc" to the list of clobbers for micro-ops where we perform
  instructions that alter %eflags.
- Use xchgl instead of cmpxchgl to release a spin lock.  This could allow
  for more efficient register allocation as we no longer mandate that %eax
  be used.
- Reenable the optimized mutex micro-ops in the non-i386 case.
2001-01-16 03:45:54 +00:00