Commit Graph

197 Commits

Author SHA1 Message Date
Julian Elischer
486a941418 Instead of doing comparisons using the pcpu area to see if
a thread is an idle thread, just see if it has the IDLETD
flag set. That flag will probably move to the pflags word
as it's permenent and never chenges for the life of the
system so it doesn't need locking.
2007-03-08 06:44:34 +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
Peter Wemm
48033188a6 Second part of commit for moving KDB_STOP_NMI from opt_global.h to
opt_kdb.h.

Found by:     kris
Approved by:  re
2005-06-30 03:38:10 +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
Warner Losh
9454b2d864 /* -> /*- for copyright notices, minor format tweaks as necessary 2005-01-06 23:35:40 +00:00
Julian Elischer
82a1dfc16d Move 4bsd specific experimental IP code into the 4bsd file.
Move the sysctls into kern.sched
2004-09-03 07:42:31 +00:00
Julian Elischer
7e37fb1729 *Blush* forgot to test non SMP builds.. oddly enough some UP code (particularly
in the acpi code) seems to want this in a UP build. (I guess so you can have
a sigle kernel module that works for both)
2004-09-01 18:05:43 +00:00
Julian Elischer
6804a3ab6d Give the 4bsd scheduler the ability to wake up idle processors
when there is new work to be done.

MFC after:	5 days
2004-09-01 06:42:02 +00:00
David E. O'Brien
dd68efd05b s/smp_rv_mtx/smp_ipi_mtx/g
Requested by:	jhb
2004-08-28 00:49:55 +00:00
Peter Wemm
f1009e1e1f Commit Doug White and Alan Cox's fix for the cross-ipi smp deadlock.
We were obtaining different spin mutexes (which disable interrupts after
aquisition) and spin waiting for delivery.  For example, KSE processes
do LDT operations which use smp_rendezvous, while other parts of the
system are doing things like tlb shootdowns with a different mutex.

This patch uses the common smp_rendezvous mutex for all MD home-grown
IPIs that spinwait for delivery.  Having the single mutex means that
the spinloop to aquire it will enable interrupts periodically, thus
avoiding the cross-ipi deadlock.

Obtained from: dwhite, alc
Reviewed by:   jhb
2004-08-23 21:39:29 +00:00
Julian Elischer
c00661f83c Don't keep evaluating our own cpu mask..
it's not likely to have changed....
2004-08-13 00:57:43 +00:00
Nate Lawson
88d2c61ee8 Move the CPU newbus attachment to i386 legacy. The acpi_cpu device will
become just "cpu" and provide attachments in the !legacy case.

Tested by:	des
2004-05-06 15:54:02 +00:00
Marcel Moolenaar
b2ae7ed72c Change the type of the various CPU masks to cpumask_t. Note that as
long as there are still explicit uses of int, whether in types or
in function names (such as atomic_set_int() in sched_ule.c), we can
not change cpumask_t to be anything other than u_int. See also the
commit log for sys/sys/types.h, revision 1.84.
2004-03-27 18:21:24 +00:00
Peter Grehan
721b6196d5 Add powerpc to temporary fix. The new cpu device claims all
'generic' OpenFirmware nexus nodes, since it uses bus_generic_probe.
Maybe the cpu device probe should be MD.
2004-03-16 13:34:50 +00:00
Ken Smith
db322c7eba This is a temporary fix to solve a regression issue on sparc64 that
is caused by the way sparc64 registers its CPUs.  Nate will work on
a real fix shortly.

Approved by:	njl
2004-03-12 20:35:21 +00:00
Nate Lawson
29f5b9a8c1 Hook CPUs up to newbus. CPUs will ultimately be a bus driver so that
multiple CPU-specific drivers can attach.  This is a work in progress
so children aren't supported yet.

Help from:	jhb
2004-03-09 03:37:21 +00:00
Jeff Roberson
b9509b56fa - Move smp_topology to subr_smp.c so that it is defined on all architectures. 2004-01-24 19:52:48 +00:00
Alfred Perlstein
1805ed0772 Introduce mp_maxcpus which can be used by libkvm utils to find out
how many CPUs the system was compiled for.
Export the variable via a sysctl node 'kern.smp.maxcpus' as well.
2003-12-23 13:54:16 +00:00
John Baldwin
45c1c90f6a Export a few SMP related symbols in UP kernels as well. This is needed to
aid other kernel code, especially code which can be in a module such as
the acpi_cpu(4) driver, to work properly with both SMP and UP kernels.
The exported symbols include mp_ncpus, all_cpus, mp_maxid, smp_started, and
the smp_rendezvous() function.  This also means that CPU_ABSENT() is now
always implemented the same on all kernels.

Approved by:	re (scottl)
2003-12-03 14:55:31 +00:00
John Baldwin
798a45964d - Split cpu_mp_probe() into two parts. cpu_mp_setmaxid() is still called
very early (SI_SUB_TUNABLES - 1) and is responsible for setting mp_maxid.
  cpu_mp_probe() is now called at SI_SUB_CPU and determines if SMP is
  actually present and sets mp_ncpus and all_cpus.  Splitting these up
  allows an architecture to probe CPUs later than SI_SUB_TUNABLES by just
  setting mp_maxid to MAXCPU in cpu_mp_setmaxid().  This could allow the
  CPU probing code to live in a module, for example, since modules
  sysinit's in modules cannot be invoked prior to SI_SUB_KLD.  This is
  needed to re-enable the ACPI module on i386.
- For the alpha SMP probing code, use LOCATE_PCS() instead of duplicating
  its contents in a few places.  Also, add a smp_cpu_enabled() function
  to avoid duplicating some code.  There is room for further code
  reduction later since much of this code is also present in cpu_mp_start().
- All archs besides i386 still set mp_maxid to the same values they set it
  to before this change.  i386 now sets mp_maxid to MAXCPU.

Tested on:	alpha, amd64, i386, ia64, sparc64
Approved by:	re (scottl)
2003-11-21 22:23:26 +00:00
John Baldwin
e57ea233d9 Ensure that mp_ncpus is set to 1 if mp_cpu_probe() fails. 2003-10-30 21:44:01 +00:00
Mike Silbersack
184dcdc7c8 Change all SYSCTLS which are readonly and have a related TUNABLE
from CTLFLAG_RD to CTLFLAG_RDTUN so that sysctl(8) can provide
more useful error messages.
2003-10-21 18:28:36 +00:00
Dag-Erling Smørgrav
633f506489 Document some sysctl variables.
Submitted by:	hmp
2003-06-12 19:46:51 +00:00
David E. O'Brien
677b542ea2 Use __FBSDID(). 2003-06-11 00:56:59 +00:00
Julian Elischer
060563ec50 Move the _oncpu entry from the KSE to the thread.
The entry in the KSE still exists but it's purpose will change a bit
when we add the ability to lock a KSE to a cpu.
2003-04-10 17:35:44 +00:00
Jeff Roberson
4093529dee - Move p->p_sigmask to td->td_sigmask. Signal masks will be per thread with
a follow on commit to kern_sig.c
 - signotify() now operates on a thread since unmasked pending signals are
   stored in the thread.
 - PS_NEEDSIGCHK moves to TDF_NEEDSIGCHK.
2003-03-31 22:49:17 +00:00
Julian Elischer
4a338afd7a Move a bunch of flags from the KSE to the thread.
I was in two minds as to where to put them in the first case..
I should have listenned to the other mind.

Submitted by:	 parts by davidxu@
Reviewed by:	jeff@ mini@
2003-02-17 09:55:10 +00:00
Jake Burkholder
dcc4093c7a Add a tunable kern.smp.disabled for disabling explicitly smp on an smp
kernel.
2002-12-28 23:21:13 +00:00
Julian Elischer
71fad9fdee Completely redo thread states.
Reviewed by:	davidxu@freebsd.org
2002-09-11 08:13:56 +00:00
Julian Elischer
e602ba25fd Part 1 of KSE-III
The ability to schedule multiple threads per process
(one one cpu) by making ALL system calls optionally asynchronous.
to come: ia64 and power-pc patches, patches for gdb, test program (in tools)

Reviewed by:	Almost everyone who counts
	(at various times, peter, jhb, matt, alfred, mini, bernd,
	and a cast of thousands)

	NOTE: this is still Beta code, and contains lots of debugging stuff.
	expect slight instability in signals..
2002-06-29 17:26:22 +00:00
Bruce Evans
c78f394575 Updated a doubly stale comment about signotify(). Fixed a nearby long line. 2002-04-05 10:00:37 +00:00
John Baldwin
6008862bc2 Change callers of mtx_init() to pass in an appropriate lock type name. In
most cases NULL is passed, but in some cases such as network driver locks
(which use the MTX_NETWORK_LOCK macro) and UMA zone locks, a name is used.

Tested on:	i386, alpha, sparc64
2002-04-04 21:03:38 +00:00
Andrew R. Reiter
dca9d05526 - Remove a semi-colon from after SYSINIT that was introduced in rev. 1.163. 2002-03-20 14:46:38 +00:00
Alfred Perlstein
4d77a549fe Remove __P. 2002-03-19 21:25:46 +00:00
Jake Burkholder
752dff3d9c Add needed includes of machine/smp.h, remove nested include in sys/smp.h
so that inlines in machine/smp.h can use variables declared in sys/smp.h.
2002-03-07 04:43:51 +00:00
Jeff Roberson
88c99cfbc8 Add a new variable mp_maxid. This is used so that per cpu datastructures may
be allocated as arrays indexed by the cpu id.  Previously the only reliable
way to know the max cpu id was through MAXCPU. mp_ncpus isn't useful here
because cpu ids may be sparsely mapped, although x86 and alpha do not do this.

Also, call cpu_mp_probe much earlier so the max cpu id is known before the VM
starts up.  This is intended to help support per cpu queues for the new
allocator, but may be useful elsewhere.

Reviewed by:	jake
Approved by:	jake
2002-03-05 10:01:46 +00:00
Peter Wemm
d5c6775903 Fix forward_roundrobin(). It was mistakenly using the cpu number as
though it was a mask.  As a result, we sent AST IPI's to the wrong
cpu and/or left out some.

Spotted by: jake
2002-01-05 09:38:47 +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
Marcel Moolenaar
1245202150 Don't remove the tentative declaration. It's the only one...
Pointy hat: marcel (self-sponsoring)
2001-10-31 20:43:38 +00:00
Marcel Moolenaar
8b3e7871bc Make smp_started volatile in sys/smp.h and remove the volatile
declaration in subr_smp.c. This solves a compile problem with
gcc 3.0.1 (ia64 cross-build).

Reviewed: jhb
2001-10-31 09:03:05 +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
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