Add a simplelock to deal with disable_intr()/enable_intr() as used in UP kernel.
UP kernel expects that this is enough to guarantee exclusive access to
regions of code bracketed by these 2 functions.
Add a simplelock to bracket clock accesses in clock.c: clock_lock.
Help from: Bruce Evans <bde@zeta.org.au>
smp_active = 1 used to indicate that the system had frozen previously
started AP's, while smp_active = 0 was "AP's not yet started". I have split
this into smp_started (which is set when the AP's come online), and
smp_active is left for turning on/off AP scheduling.
- We now have enough per-cpu idle context, the real idle loop has been
revived (cpu's halt now with nothing to do).
- Some preliminary support for running some operations outside the
global lock (eg: zeroing "free but not yet zeroed pages") is present
but appears to cause problems. Off by default.
- the smp_active sysctl now behaves differently. It's merely a 'true/false'
option. Setting smp_active to zero causes the AP's to halt in the idle
loop and stop scheduling processes.
- bootstrap is a lot safer. Instead of sharing a statically compiled in
stack a number of times (which has caused lots of problems) and then
abandoning it, we use the idle context to boot the AP's directly. This
should help >2 cpu support since the bootlock stuff was in doubt.
- print physical apic id in traps.. helps identify private pages getting
out of sync. (You don't want to know how much hair I tore out with this!)
More cleanup to follow, this is more of a checkpoint than a
'finished' thing.
This unifies several times in theory indentical 50 lines of code.
The filesystems have a new method: vop_cachedlookup, which is the
meat of the lookup, and use vfs_cache_lookup() for their vop_lookup
method. vfs_cache_lookup() will check the namecache and pass on
to the vop_cachedlookup method in case of a miss.
It's still the task of the individual filesystems to populate the
namecache with cache_enter().
Filesystems that do not use the namecache will just provide the
vop_lookup method as usual.
Added a new variable, 'bsp_apic_ready', which is set as soon as the bootstrap
CPU has initialized its local APIC. Conditionalize the GENSPLR functions
to call ss_lock ONLY after bsp_apic_ready is TRUE; This should prevent
any problems with races between the time the 1st AP becomes ready and the
time smp_active is set.
free list problem. Also, the vnode age flag is no longer used by the
vnode pager. (It is actually incorrect to use then.) Constructive
feedback welcome -- just be kind.
Made NEW_STRATEGY default.
Removed misc. old cruft.
Centralized simple locks into mp_machdep.c
Centralized simple lock macros into param.h
More cleanup in the direction of making splxx()/cpl MP-safe.
Several new fine-grained locks.
New FAST_INTR() methods:
- separate simplelock for FAST_INTR, no more giant lock.
- FAST_INTR()s no longer checks ipending on way out of ISR.
sio made MP-safe (I hope).
same syscall number as NetBSD/OpenBSD. The getpgid() came from NetBSD
(I think) originally, but it's basically cut/paste/edit from the other
simple get*() syscalls.
VM systems usage of the kernel lock (lockmgr) code. This is a first
pass implementation, and is expected to evolve as needed. The API
for the lock manager code has not changed, but the underlying implementation
has changed significantly. This change should not materially affect
our current SMP or UP code without non-standard parameters being used.
This version.
1/ avoids garret's introduced potential page fault. (I got one)
2/ removes compiler warnings
Also fix the tunable scheduling quantum to return a better error code when
fed a bad argument.
socket addresses in mbufs. (Socket buffers are the one exception.) A number
of kernel APIs needed to get fixed in order to make this happen. Also,
fix three protocol families which kept PCBs in mbufs to not malloc them
instead. Delete some old compatibility cruft while we're at it, and add
some new routines in the in_cksum family.
We now tsleep() in kthread_init() between start_init()
and prepare_usermode() while waiting for ALL the idle_loop()
processes to come online.
Debugged & tested by: "Thomas D. Dean" <tomdean@ix.netcom.com>
Reviewed by: David Greenman <dg@root.com>
as chargeable CPU usage. This should mitigate the problem of processes
doing disk I/O hogging the CPU. Various users have reported the
problem, and test code shows that the problem should now be gone.
