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
Also removed some spl's and added some VM mutexes, but they are not actually
used yet, so this commit does not really make any operational changes
to the system.
vm_page.c relates to vm_page_t manipulation, including high level deactivation,
activation, etc... vm_pageq.c relates to finding free pages and aquiring
exclusive access to a page queue (exclusivity part not yet implemented).
And the world still builds... :-)
(this commit is just the first stage). Also add various GIANT_ macros to
formalize the removal of Giant, making it easy to test in a more piecemeal
fashion. These macros will allow us to test fine-grained locks to a degree
before removing Giant, and also after, and to remove Giant in a piecemeal
fashion via sysctl's on those subsystems which the authors believe can
operate without Giant.
.cvsignore file for [A-Za-z]* to keep these directories around rather
than waste a file on .keepme. This should also make people's built
trees place nice with CVS.
Idea for .cvsignore: peter (although I suggested the regexp)
Pointed out by: Makoto MATSUSHITA-san <matusita@jp.FreeBSD.org>
Llama's costuming by: Fernamdo Llamas
us our first minimal glimpse of PowerPC support.
With this code we can get to the "mountroot>" prompt on my Apple iMac. We
can't get any further due to lack of clock and interrupt handling, among other
things. This does however mean that pmap and VM are initialising.
We're fairly dependant on OpenFirmware at this point, but I hope to add
support for other classes of firmware at a later stage.
Reviewed by: obrien, dfr
systems were repo-copied from sys/miscfs to sys/fs.
- Renamed the following file systems and their modules:
fdesc -> fdescfs, portal -> portalfs, union -> unionfs.
- Renamed corresponding kernel options:
FDESC -> FDESCFS, PORTAL -> PORTALFS, UNION -> UNIONFS.
- Install header files for the above file systems.
- Removed bogus -I${.CURDIR}/../../sys CFLAGS from userland
Makefiles.
registers better. Hold sched_lock not only for checking the flag but
also while performing the actual operation to ensure the process doesn't
get swapped out by another CPU while we the operation is being performed.
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
structure. This field keeps track of how many levels deep we are nested
into the kernel. The nesting level is bumped at the start of a trap,
interrupt, syscall, or exception and is decremented on return. This is
used to detect the case when the kernel is returning back to a kernel
context in exception_return(). If we are returning to the kernel we need
to update the globaldata pointer register saved in the stack frame in case
we have switched CPU's between taking the initial interrupt that saved the
frame and returning. If we don't do this fixup it is possible for a CPU to
use the wrong per-cpu data. On UP systems this is not a problem, so the
code is conditional on SMP.
A count was used instead of simply checking the process status register in
the frame during exception_return() since there are critical sections at
the very start and end of a trap, exception, or interrupt from userland in
which we could trash the t7 register being used in userland. The counter
is incremented after adn before these critical sections respectively so
that we will not overwrite the saved t7 register if we are interrupted
during one of these critical sections.
