with system statistics monitoring tools (such as systat, vmstat...)
because of stopping RTC interrupts generation.
Restore all the timers (RTC and i8254) atomically.
Reviewed by: bde
MFC after: 1 week
o Unify <machine/endian.h>'s across all architectures.
o Make bswapXX() functions use a different spelling of u_int16_t and
friends to reduce namespace pollution. The bswapXX() functions
don't actually exist, but we'll probably import these at some
point. Atleast one driver (if_de) depends on bswapXX() for big
endian cases.
o Deprecate byteorder(3) prototypes from <sys/types.h>, these are
now prototyped indirectly in <arpa/inet.h>.
o Deprecate in_addr_t and in_port_t typedefs in <sys/types.h>, these
are now typedef'd in <arpa/inet.h>.
o Change byteorder(3) prototypes to use standards compliant uint32_t
(spelled __uint32_t to reduce namespace pollution).
o Document new preferred headers and standards compliance.
Discussed with: bde
PR: 29946
Reviewed by: bmilekic
level implementation stuff out of machine/globaldata.h to avoid exposing
UPAGES to lots more places. The end result is that we can double
the kernel stack size with 'options UPAGES=4' etc.
This is mainly being done for the benefit of a MFC to RELENG_4 at some
point. -current doesn't really need this so much since each interrupt
runs on its own kstack.
and such was just a bad idea and one that users should be forced to
enable if they want it. This patch introduces a hw.pci.enable_pcibios
tunable for those people. This does not impact the pcibios interrupt
routing at all.
Approved by: peter, msmith
some bios vendors took it apon themselves to "censor" the
host->pci bridges from PCIBIOS callers, even when the caller
explicitly asks for them. This includes certain Compaq machines
(eg: DL360) and some laptops.
If we detect this, shut down pcibios and revert to using IO
port bashing.
Under -current, apcica does a better job anyway.
information. The default limits only effect machines with > 1GB of ram
and can be overriden with two new kernel conf variables VM_SWZONE_SIZE_MAX
and VM_BCACHE_SIZE_MAX, or with loader variables kern.maxswzone and
kern.maxbcache. This has the effect of leaving more KVM available for
sizing NMBCLUSTERS and 'maxusers' and should avoid tripups where a sysad
adds memory to a machine and then sees the kernel panic on boot due to
running out of KVM.
Also change the default swap-meta auto-sizing calculation to allocate half
of what it was previously allocating. The prior defaults were way too high.
Note that we cannot afford to run out of swap-meta structures so we still
stay somewhat conservative here.
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)
are a really nasty interface that should have been killed long ago
when 'ptrace(PT_[SG]ETREGS' etc came along. The entity that they
operate on (struct user) will not be around much longer since it
is part-per-process and part-per-thread in a post-KSE world.
gdb does not actually use this except for the obscure 'info udot'
command which does a hexdump of as much of the child's 'struct user'
as it can get. It carries its own #defines so it doesn't break
compiles.
dynamic symbol table buckets and chains. The sparc64 toolchain uses 32
bit .hash entries, unlike other 64 bits architectures (alpha), which use
64 bit entries.
Discussed with: dfr, jdp
were indices in a dense array. The cpuids are a sparse set and treat
them as such, setting up containers only for CPUs activated during
mb_init().
- Fix netstat(1) and systat(1) to treat the per-CPU stats area as a sparse
map, in accordance with the above.
This allows us to properly boot with certain CPUs disactivated. However, if
we later decide to re-activate said CPUs, we will barf until we decide to
implement CPU spinon/spinoff callback hooks to allow for said CPUs' per-CPU
containers to get configured on their activation.
Reported by: mjacob
Partially (sys/ diffs) Submitted by: mjacob
we are required to do if we let user processes use the extra 128 bit
registers etc.
This is the base part of the diff I got from:
http://www.issei.org/issei/FreeBSD/sse.html
I believe this is by: Mr. SUZUKI Issei <issei@issei.org>
SMP support apparently by: Takekazu KATO <kato@chino.it.okayama-u.ac.jp>
Test code by: NAKAMURA Kazushi <kaz@kobe1995.net>, see
http://kobe1995.net/~kaz/FreeBSD/SSE.en.html
I have fixed a couple of style(9) deviations. I have some followup
commits to fix a couple of non-style things.
Add a CAPI (hardware independent) driver i4bcapi(4) and hardware driver
iavc (4) to support active CAPI-based BRI and PRI cards (currently AVM
B1 and T1 cards) to isdn4bsd.
simpler for npx exceptions that start as traps (no assembly required...)
and works better for npx exceptions that start as interrupts (there is
no longer a problem for nested interrupts).
Submitted by: original (pre-SMPng) version by luoqi
. FD_CLRERR clears the error counter, thus re-enables kernel error
printf()s,
. FD_GSTAT obtains the last FDC operation state, if any,
. FDOPT_NOERRLOG (temporarily) turns off kernel printf() floppy
error logging,
. FDOPT_NOERROR makes the kernel ignore an FDC error, thus can
enable the transfer of an erroneous sector to the user application
All options are being cleared on (last) close.
Prime consumer of the last features will be fdread(1), to be committed
shortly.
(FD_CLRERR should be wired into fdcontrol(8), but then fdcontrol(8)
needs a major rewrite anyway.)
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
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)
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
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.
are some good reasons for not doing this, even if the linting of
the code breaks.
1) If lint were ever to understand the stuff inside the macros,
that would break the checks.
2) There are ways to use __GNUC__ to exclude overly specific
code.
3) (Not yet practical) Lint(1) needs to properlyu understand
all of te code we actually run.
Complained about by: bde
Education by: jake, jhb, eivind
API for IPI's that isn't tied to the Intel APIC. MD code can still use
the apic_ipi() function or dink with the apic directly if needed to send
MD IPI's.
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.
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.
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.
- 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.
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.
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.
Make the name cache hash as well as the nfsnode hash use it.
As a special tweak, create an unsigned version of register_t. This allows
us to use a special tweak for the 64 bit versions that significantly
speeds up the i386 version (ie: int64 XOR int64 is slower than int64
XOR int32).
The code layout is a little strange for the string function, but I was
able to get between 5 to 10% improvement over the original version I
started with. The layout affects gcc code generation choices and this way
was fastest on x86 and alpha.
Note that 'CPUTYPE=p3' etc makes a fair difference to this. It is
around 45% faster with -march=pentiumpro on a p6 cpu.
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>
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
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
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
to be more like Xint0x80_syscall and less like c function syscall().
- Reduce code duplication between the int0x80 and lcall handlers by
shuffling the elfags into the right place, saving the sizeof the
instruction in tf_err and jumping into the common int0x80 code.
Reviewed by: peter
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
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.
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.
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.
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
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.
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)
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) :-)
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)
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
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
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.
pre-emptable kernel. For variables of size 4 bytes or less they compile
to a single instruction, which does not allow a process to migrate cpus
in the middle, and get the value for the "wrong" cpu.
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.
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.
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.
that modules can call.
- Remove the old gcc <= 2.8 versions of the atomic ops.
- Resort the order of some things in the file so that there is only
one #ifdef for KLD_MODULE, and so that all WANT_FUNCTIONS stuff is
moved to the bottom of the file.
- Remove ATOMIC_ACQ_REL() and just use explicit macros instead.
implement memory fences for the 486+. The 386 still uses versions w/o
memory fences as all operations on the 386 are not program ordered.
The 386 versions are not MP safe.
__FreeBSD_version 500015 can be used to detect their disappearance.
- Move the symbols for SMP_prvspace and lapic from globals.s to
locore.s.
- Remove globals.s with extreme prejudice.
symbols in globals.s.
PCPU_GET(name) returns the value of the per-cpu variable
PCPU_PTR(name) returns a pointer to the per-cpu variable
PCPU_SET(name, val) sets the value of the per-cpu variable
In general these are not yet used, compatibility macros remain.
Unifdef SMP struct globaldata, this makes variables such as cpuid
available for UP as well.
Rebuilding modules is probably a good idea, but I believe old
modules will still work, as most of the old infrastructure
remains.
as multi-processor kernels. The old way made it difficult for kernel
modules to be portable between uni-processor and multi-processor
kernels. It is no longer necessary to jump through hoops.
- always load %fs with the private segment on entry to the kernel
- change the type of the self referntial pointer from struct privatespace
to struct globaldata
- make the globaldata symbol have value 0 in all cases, so the symbols
in globals.s are always offsets, not aliases for fields in globaldata
- define the globaldata space used for uniprocessor kernels in C, rather
than assembler
- change the assmebly language accessors to use %fs, add a macro
PCPU_ADDR(member, reg), which loads the register reg with the address
of the per-cpu variable member
To use it, some dll is needed. And currently, the dll is only for NetBSD.
So one more kernel module is needed.
For more infomation,
http://chiharu.haun.org/peace/ .
Reviewed by: bp
variables from i386 assembly language. The syntax is PCPU(member)
where member is the capitalized name of the per-cpu variable, without
the gd_ prefix. Example: movl %eax,PCPU(CURPROC). The capitalization
is due to using the offsets generated by genassym rather than the symbols
provided by linking with globals.o. asmacros.h is the wrong place for
this but it seemed as good a place as any for now. The old implementation
in asnames.h has not been removed because it is still used to de-mangle
the symbols used by the C variables for the UP case.
the witness code is compiled in. Without this, the witness code doesn't
notice that sched_lock is released by fork_trampoline() and thus gets all
confused about spin lock order later on.
calling the C functions mtx_enter_hard() and mtx_exit_hard() clobbers them.
Note that %eax is also not call safe, but it is already clobbered due to
cmpxchg. However, now we are back to not compiling again, so these macros
are still left disabled for now.
that of MTX_EXIT. Don't assume that the reg parameter to MTX_ENTER
holds curproc, load it explicitly. Put semi-colons at the end of
the macros to be more consistent and so its harder to forget them
when these change.
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.
mpapic.c. This gives us the benefit of C type checking. These functions
are not called in any critical paths and are not used by the interrupt
routines.
spending, which was unused now that all software interrupts have
their own thread. Make the legacy schednetisr use an atomic op
for setting bits in the netisr mask.
Reviewed by: jhb
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
MPLOCKED macro
(2) Use decimal 12 rather than hex 0xc in an addl
(3) Implement MTX_ENTER for the I386_CPU case
(4) Use semi-colons between instructions to allow MTX_ENTER
and MTX_ENTER_WITH_RECURSION to be assembled
(5) Use incl instead of incw to increment the recusion count
(6) 10 is not a valid label, use 7, 8 and 9 rather than 8, 9 and 10
(7) Sort numeric labels
Submitted by: bde (2, 4, and 5)
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
-current and RELENG_4 with GENERIC.
NKPT is the number of initial bootstrap page table pages we create for
the kernel during startup. Once VM is up, we resize it as needed, but
with 4G ram, the size of the vm_page_t structures was pushing it over
the limit. The fact that trimmed down kernels boot on 4G ram machines
suggests that we were pretty close to the edge.
The "30" is arbitary, but smaller than the 'nkpt' variable on all
machines that I checked.
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.
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