Commit Graph

86 Commits

Author SHA1 Message Date
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
Roger Pau Monné
ef409ede7b amd64/i386: introduce APIC hooks for different APIC implementations.
This is needed for Xen PV(H) guests, since there's no hardware lapic
available on this kind of domains. This commit should not change
functionality.

Sponsored by: Citrix Systems R&D
Reviewed by: jhb
Approved by: gibbs

amd64/include/cpu.h:
amd64/amd64/mp_machdep.c:
i386/include/cpu.h:
i386/i386/mp_machdep.c:
 - Remove lapic_ipi_vectored hook from cpu_ops, since it's now
   implemented in the lapic hooks.

amd64/amd64/mp_machdep.c:
i386/i386/mp_machdep.c:
 - Use lapic_ipi_vectored directly, since it's now an inline function
   that will call the appropiate hook.

x86/x86/local_apic.c:
 - Prefix bare metal public lapic functions with native_ and mark them
   as static.
 - Define default implementation of apic_ops.

x86/include/apicvar.h:
 - Declare the apic_ops structure and create inline functions to
   access the hooks, so the change is transparent to existing users of
   the lapic_ functions.

x86/xen/hvm.c:
 - Switch to use the new apic_ops.
2014-06-16 08:43:03 +00:00
John Baldwin
63e62d390d Add a resume hook for bhyve that runs a function on all CPUs during
resume.  For Intel CPUs, invoke vmxon for CPUs that were in VMX mode
at the time of suspend.

Reviewed by:	neel
2013-12-23 19:48:22 +00:00
Justin T. Gibbs
566a5f5020 Merge Xen PVHVM support into the GENERIC kernel config for both
amd64 and i386.

Submitted by:	Roger Pau Monné
Sponsored by:	Citrix Systems R&D
Reviewed by:	gibbs
Approved by:	re (blanket Xen)
MFC after:	2 weeks

sys/amd64/amd64/mp_machdep.c:
sys/amd64/include/cpu.h:
sys/i386/i386/mp_machdep.c:
sys/i386/include/cpu.h:
	- Introduce two new CPU hooks for initialization and resume
	  purposes. This allows us to get rid of the XENHVM ifdefs in
	  mp_machdep, and also sets some hooks into common code that can be
	  used by other hypervisor implementations.

sys/amd64/conf/XENHVM:
sys/i386/conf/XENHVM:
	- Remove these configs now that GENERIC has builtin support for Xen
	  HVM.

sys/kern/subr_smp.c:
	- Make sure there are no pending IPIs when suspending a system.

sys/x86/xen/hvm.c:
	- Add cpu init and resume vectors that are called from mp_machdep
	  using the new hooks.
	- Only clear the vcpu_info mapping data on resume.  It is already
	  clear for the BSP on a cold boot and is set correctly as APs
	  are started.
	- Gate xen_hvm_init_cpu only to systems running under Xen.

sys/x86/xen/xen_intr.c:
	 - Gate the setup of event channels only to systems running under Xen.
2013-09-20 22:59:22 +00:00
Justin T. Gibbs
e44af46e4c Implement PV IPIs for PVHVM guests and further converge PV and HVM
IPI implmementations.

Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Submitted by: gibbs (misc cleanup, table driven config)
Reviewed by:  gibbs
MFC after: 2 weeks

sys/amd64/include/cpufunc.h:
sys/amd64/amd64/pmap.c:
	Move invltlb_globpcid() into cpufunc.h so that it can be
	used by the Xen HVM version of tlb shootdown IPI handlers.

sys/x86/xen/xen_intr.c:
sys/xen/xen_intr.h:
	Rename xen_intr_bind_ipi() to xen_intr_alloc_and_bind_ipi(),
	and remove the ipi vector parameter.  This api allocates
	an event channel port that can be used for ipi services,
	but knows nothing of the actual ipi for which that port
	will be used.  Removing the unused argument and cleaning
	up the comments surrounding its declaration helps clarify
	its actual role.

sys/amd64/amd64/mp_machdep.c:
sys/amd64/include/cpu.h:
sys/i386/i386/mp_machdep.c:
sys/i386/include/cpu.h:
	Implement a generic framework for amd64 and i386 that allows
	the implementation of certain CPU management functions to
	be selected at runtime.  Currently this is only used for
	the ipi send function, which we optimize for Xen when running
	on a Xen hypervisor, but can easily be expanded to support
	more operations.

sys/x86/xen/hvm.c:
	Implement Xen PV IPI handlers and operations, replacing native
	send IPI.

sys/amd64/include/pcpu.h:
sys/i386/include/pcpu.h:
sys/i386/include/smp.h:
	Remove NR_VIRQS and NR_IPIS from FreeBSD headers.  NR_VIRQS
	is defined already for us in the xen interface files.
	NR_IPIS is only needed in one file per Xen platform and is
	easily inferred by the IPI vector table that is defined in
	those files.

sys/i386/xen/mp_machdep.c:
	Restructure to more closely match the HVM implementation by
	performing table driven IPI setup.
2013-09-06 22:17:02 +00:00
Andriy Gapon
a29cc9a34b Revert r253748,253749
This WIP should not have been committed yet.

Pointyhat to:	avg
2013-07-28 18:44:17 +00:00
Andriy Gapon
366d8bfb7b put contents of cpu.h under _KERNEL
no userland-serviceable parts inside

MFC after:	20 days
2013-07-28 18:32:27 +00:00
Jung-uk Kim
38b8542ca9 Deprecate tsc_present as the last of its real consumers finally disappeared. 2011-03-15 17:19:52 +00:00
Jung-uk Kim
dd7d207dcb Merge sys/amd64/amd64/tsc.c and sys/i386/i386/tsc.c and move to sys/x86/x86.
Discussed with:	avg
2010-12-08 00:09:24 +00:00
Warner Losh
1003cfe94d Remove obsolete undef of COPY_SIGCODE. It appears to have not been
used in FreeBSD in quite some time (maybe since before 4.4-lite :)

Submitted by:	bde
2010-07-13 15:06:13 +00:00
Poul-Henning Kamp
5405ab4889 Clean out sysctl machdep.* related defines.
The cmos clock related stuff should really be in MI code.
2006-05-11 17:29:25 +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
Maxime Henrion
9f1b87f106 Instead of calling ia32_pause() conditionally on __i386__ or __amd64__
being defined, define and use a new MD macro, cpu_spinwait().  It only
expands to something on i386 and amd64, so the compiled code should be
identical.

Name of the macro found by:	jhb
Reviewed by:	jhb
2004-08-03 18:44:27 +00:00
Bruce Evans
4c5f10a672 Backed out previous commit. Blind substitution of dev_t by `struct cdev *'
was just wrong here because the dev_t's are user dev_t's.
2004-06-20 03:52:50 +00:00
Poul-Henning Kamp
89c9c53da0 Do the dreaded s/dev_t/struct cdev */
Bump __FreeBSD_version accordingly.
2004-06-16 09:47:26 +00:00
Warner Losh
29ae923f44 Remove advertising clause from University of California Regent's license,
per letter dated July 22, 1999.

Approved by: core
2004-04-05 21:29:41 +00:00
Peter Wemm
cd3402fa66 Sync with i386 version. The quality initialization was missing and some
other junk.
2003-09-23 00:18:45 +00:00
Marcel Moolenaar
26502503e5 Further cleanup <machine/cpu.h> and <machine/md_var.h>: move the MI
prototypes of cpu_halt(), cpu_reset() and swi_vm() from md_var.h to
cpu.h. This affects db_command.c and kern_shutdown.c.

ia64: move all MD prototypes from cpu.h to md_var.h. This affects
madt.c, interrupt.c and mp_machdep.c. Remove is_physical_memory().
It's not used (vm_machdep.c).

alpha: the MD prototypes have been left in cpu.h with a comment
that they should be there. Moving them is left for later. It was
expected that the impact would be significant enough to be done in
a seperate commit.

powerpc: MD prototypes left in cpu.h. Comment added.

Suggested by: bde
Tested with: make universe (pc98 incomplete)
2003-08-16 16:57:57 +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
Poul-Henning Kamp
553ebddc59 Make get_cyclecount() use binuptime() when no tsc is available: it is cheaper. 2003-02-05 08:55:10 +00:00
Alfred Perlstein
b63dc6ad47 Remove __P. 2002-03-20 05:48:58 +00:00
John Baldwin
0bbc882680 Overhaul the per-CPU support a bit:
- The MI portions of struct globaldata have been consolidated into a MI
  struct pcpu.  The MD per-CPU data are specified via a macro defined in
  machine/pcpu.h.  A macro was chosen over a struct mdpcpu so that the
  interface would be cleaner (PCPU_GET(my_md_field) vs.
  PCPU_GET(md.md_my_md_field)).
- All references to globaldata are changed to pcpu instead.  In a UP kernel,
  this data was stored as global variables which is where the original name
  came from.  In an SMP world this data is per-CPU and ideally private to each
  CPU outside of the context of debuggers.  This also included combining
  machine/globaldata.h and machine/globals.h into machine/pcpu.h.
- The pointer to the thread using the FPU on i386 was renamed from
  npxthread to fpcurthread to be identical with other architectures.
- Make the show pcpu ddb command MI with a MD callout to display MD
  fields.
- The globaldata_register() function was renamed to pcpu_init() and now
  init's MI fields of a struct pcpu in addition to registering it with
  the internal array and list.
- A pcpu_destroy() function was added to remove a struct pcpu from the
  internal array and list.

Tested on:	alpha, i386
Reviewed by:	peter, jake
2001-12-11 23:33:44 +00:00
Julian Elischer
b40ce4165d KSE Milestone 2
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.

Sorry john! (your next MFC will be a doosie!)

Reviewed by: peter@freebsd.org, dillon@freebsd.org

X-MFC after:    ha ha ha ha
2001-09-12 08:38:13 +00:00
John Baldwin
688ebe120c - Close races with signals and other AST's being triggered while we are in
the process of exiting the kernel.  The ast() function now loops as long
  as the PS_ASTPENDING or PS_NEEDRESCHED flags are set.  It returns with
  preemption disabled so that any further AST's that arrive via an
  interrupt will be delayed until the low-level MD code returns to user
  mode.
- Use u_int's to store the tick counts for profiling purposes so that we
  do not need sched_lock just to read p_sticks.  This also closes a
  problem where the call to addupc_task() could screw up the arithmetic
  due to non-atomic reads of p_sticks.
- Axe need_proftick(), aston(), astoff(), astpending(), need_resched(),
  clear_resched(), and resched_wanted() in favor of direct bit operations
  on p_sflag.
- Fix up locking with sched_lock some.  In addupc_intr(), use sched_lock
  to ensure pr_addr and pr_ticks are updated atomically with setting
  PS_OWEUPC.  In ast() we clear pr_ticks atomically with clearing
  PS_OWEUPC.  We also do not grab the lock just to test a flag.
- Simplify the handling of Giant in ast() slightly.

Reviewed by:	bde (mostly)
2001-08-10 22:53:32 +00:00
John Baldwin
6be523bca7 Add a new MI pointer to the process' trapframe p_frame instead of using
various differently named pointers buried under p_md.

Reviewed by:	jake (in principle)
2001-06-29 11:10:41 +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
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
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
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
John Baldwin
5b8c74d59a - Proc locking.
- P_OWEUPC -> PS_OWEUPC.
- Remove obsolete prototype for MD fork_return().
2001-01-24 09:56:49 +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
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
Poul-Henning Kamp
45b031c5e4 Move extern tsc_present outside function to quelch a warning. 2000-12-07 22:30:11 +00:00
Mark Murray
4a3a2f0704 Namespace cleanup. Remove some #includes in favour of an explicit
declaration.

Asked for by:	bde
2000-12-02 17:59:41 +00:00
Marcel Moolenaar
d034d459da Don't use p->p_sigstk.ss_flags to keep state of whether the
process is on the alternate stack or not. For compatibility
with sigstack(2) state is being updated if such is needed.

We now determine whether the process is on the alternate
stack by looking at its stack pointer. This allows a process
to siglongjmp from a signal handler on the alternate stack
to the place of the sigsetjmp on the normal stack. When
maintaining state, this would have invalidated the state
information and causing a subsequent signal to be delivered
on the normal stack instead of the alternate stack.

PR: 22286
2000-11-30 05:23:49 +00:00
Mark Murray
5855006767 Add a consistent API to a feature that most modern CPUs have; a fast
counter register in-CPU.

This is to be used as a fast "timer", where linearity is more important
than time, and multiple lines in the linearity caused by multiple CPUs
in an SMP machine is not a problem.

This adds no code whatsoever to the FreeBSD kernel until it is actually
used, and then as a single-instruction inline routine (except for the
80386 and 80486 where it is some more inline code around nanotime(9).

Reviewed by:	bde, kris, jhb
2000-11-21 19:55:21 +00:00
Bruce Evans
4a3bb59944 Declare or #define per-cpu globals in <machine/globals.h> in all cases.
The i386 UP case was messily different.
2000-10-27 08:30:59 +00:00
Bruce Evans
9a25c23635 Moved the definitions of AST_PENDING and AST_RESCHED to the correct place. 2000-10-12 11:13:27 +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
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
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
Peter Dufault
383774c417 Patches that eliminate extra context switches in FIFO case.
Fixes p1003_1b regression test in the simple case of no RR and
FIFO processes competing.

Reviewed by:	jkh, bde
2000-03-02 16:20:07 +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
Peter Wemm
c3aac50f28 $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
Bruce Evans
eec2e836e9 Go back to the old (icu.s rev.1.7 1993) way of keeping the AST-pending
bit separate from ipending, since this is simpler and/or necessary for
SMP and may even be better for UP.

Reviewed by:	alc, luoqi, tegge
1999-07-10 15:28:01 +00:00
Dmitrij Tejblum
0666dbe1cf Moved cpu_set_fork_handler's prototype from <machine/cpu.h> to <sys/proc.h>.
Suggested by:	bde
1999-04-23 20:22:44 +00:00
Bruce Evans
79a2501238 Added a hopefully-machine-independent macro for determining if a
reschedule is pending.
1999-02-02 09:08:23 +00:00
Matthew Dillon
3cfc69e6c2 More -Wall / -Wcast-qual cleanup. Also, EXEC_SET can't use
C_DECLARE_MODULE due to the linker_file_sysinit() function
    making modifications to the data.
1999-01-29 08:36:45 +00:00