The implementation is done (unlike what i've originally been
contemplating) by reparenting kids of processes that have the
appropriate bit set to PID 1, and let PID 1 handle the zombie. This
is far less problematical than what would seem to be ``doing it
right'', for a number of reasons.
Of our currently shipping PID-1-intended programs, 50 % fail the above
assumption. ;-) (Read this: sysinstall doesn't do it right. This is
no problem as long as no program called by sysinstall actually uses
SA_NOCLDWAIT.)
ToDo: . clarify the correct SA_* flag inheritance, compared
to other systems,
. decide whether the compat cruft (osigvec(9)) should
deal with new system additions or not,
. merge OpenBSD's SA_SIGINFO implementation. ;)
Reviewed by: bde
local filesystem metadata at the first brelse call when the
block device vnode has v_tag set to VT_NFS.
Reviewed by: phk
Submitted by: Tor Egge <tegge@idi.ntnu.no>
declaration macros so that a semicolon can be added when the macros
are invoked without giving a (pedantic) syntax error. Invocations
need to be followed by a semicolon so that programs like indent and
gtags don't get confused.
Fixed the one invocation that wasn't followed by a trailing semicolon.
since that might cause in_pcballoc to call MALLOC with M_WAITOK during
a software interrupt.
Reviewed by: Garrett Wollman <wollman@khavrinen.lcs.mit.edu>
Introduce VFREE which indicates that vnode is on freelist.
Rename vholdrele() to vdrop().
Create vfree() and vbusy() to add/delete vnode from freelist.
Add vfree()/vbusy() to keep (v_holdcnt != 0 || v_usecount != 0)
vnodes off the freelist.
Generalize vhold()/v_holdcnt to mean "do not recycle".
Fix reassignbuf()s lack of use of vhold().
Use vhold() instead of checking v_cache_src list.
Remove vtouch(), the vnodes are always vget'ed soon enough
after for it to have any measuable effect.
Add sysctl debug.freevnodes to keep track of things.
Move cache_purge() up in getnewvnodes to avoid race.
Decrement v_usecount after VOP_INACTIVE(), put a vhold() on
it during VOP_INACTIVE()
Unmacroize vhold()/vdrop()
Print out VDOOMED and VFREE flags (XXX: should use %b)
Reviewed by: dyson
holding CPU along with the lock. When a CPU fails to get the lock
it compares its own id to the holder id. If they are the same it
panic()s, as simple locks are binary, and this would cause a deadlock.
Controlled by smptests.h: SL_DEBUG, ON by default.
Some minor cleanup.
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.
