held.
The only place where we want to not hold topology is when we read
(or write) the label to disk: in the case of a disk error with a
long recovery time, holding topology would prevent open/close of
any disk device.
rename them appropriately. Protect both flags with both the proc lock
and the sched_lock.
- Protect p_profthreads with the proc lock.
- Remove Giant from profil(2).
- For the 4BSD scheduler, this means that all callers of the static
function resetpriority() now always hold sched_lock, so don't lock
sched_lock explicitly in that function.
kg_nice is now protected by both. Being protected by both means that
other places in the kernel that want to read kg_nice only need one of the
two locks.
race where a thread could assume that a process was swapped in by
PHOLD() when it actually wasn't fully swapped in yet.
- In faultin(), always msleep() if PS_SWAPPINGIN is set instead of doing
this check after bumping p_lock in the PS_INMEM == 0 case. Also,
sched_lock is only needed for setting and clearning swapping PS_*
flags and the swap thread inhibitor.
- Don't set and clear the thread swap inhibitor in the same loops as the
pmap_swapin/out_thread() since we have to do it under sched_lock.
Instead, mimic the treatment of the PS_INMEM flag and use separate loops
to set the inhibitors when clearing PS_INMEM and clear the inhibitors
when setting PS_INMEM.
- swapout() now returns with the proc lock held as it holds the lock
while adjusting the swapping-related PS_* flags so that the proc lock
can be used to test those flags.
- Only use the proc lock to check the swapping-related PS_* flags in
several places.
- faultin() no longer requires sched_lock to be held by callers.
- Rename PS_SWAPPING to PS_SWAPPINGOUT to be less ambiguous now that we
have PS_SWAPPINGIN.
their prototypes.
- Remove sched_lock locking from kse_purge() as all callers already lock
the sched_lock before calling it.
- Hold the proc lock slightly longer to protect P_SHOULDSTOP().
or sched_lock are sufficient to test this flag.
XXX: vinum should really be using a kernel process via kthread_create()
instead of this hack. I'm not even sure PS_INMEM can be clear at this
point anyways.
kern_sigprocmask() in the various binary compatibility emulators.
- Replace calls to sigsuspend(), sigaltstack(), sigaction(), and
sigprocmask() that used the stackgap with calls to the corresponding
kern_sig*() functions instead without using the stackgap.
cpu_switch_load_gs, cpu is in context switch, so don't enable interrupt.
because it is in context switch, it is expected sched_lock was held,
so don't PROC_LOCK(p) and psignal, it is LOR, probably we can
set a P_XSIGBUS like flag in p_sflags, and set TDF_ASTPENDING in
td_flags, in ast(), post a SIGBUS to process if P_XSIGBUS was set.
called without Giant; and obj_alloc() in turn calls vm_page_alloc()
without Giant. This causes an assertion failure in vm_page_alloc().
Fortunately, obj_alloc() is now MPSAFE. So, we need only clean up
some assertions.
- Weaken the assertion in vm_page_lookup() to require Giant only
if the vm_object isn't locked.
- Remove an assertion from vm_page_alloc() that duplicates a check
performed in vm_page_lookup().
In collaboration with: gallatin, jake, jeff
instruction requires that a translation is present in the TC. This
may trigger a TLB miss and a subsequent call to vm_fault().
This implementation is deliberately non-inline for debugging and
profiling purposes. Partial or full inlining should eventually be
done.
Valuable insights by: jake
This means that you can no longer trash your opened partitions by writing to
the sunlabel through another partition. This is similar to the semantics
implemented for BSD labels.
if attach succeeded. device_is_alive just tells us that probe
succeeded. Since we were using it to do things like detach net
interfaces, this caused problems when there were errors in the attach
routine.
Symptoms of problem reported by: martin blapp
o KMF_NOUPCALL
Ask kse_release to not return to userland upcall entry, but instead
direct returns to userland by using current thread's stack and return
address on stack. This flags is intended to be used by UTS in critical
region to wait another UTS thread to leave critical region, by using
kse_release with this flag to avoid spinnng and burning CPU. Also this
flags can be used by UTS to poll completed context when there is nothing
to do in userland and needn't restart from its entry like normal upcall.
o KMF_NOCOMPLETED
Ask kernel to not bring completed thread contexts back to userland when
doing upcall, this flags is intend to be used with above flag when an
upcall thread is in critical region and can not process completed contexts
at that time.
Tested by: deischen
vm_object_pip_add() and vm_object_pip_wakeup().
- Remove GIANT_REQUIRED from vm_object_pip_subtract() and
vm_object_pip_subtract().
- Lock the vm_object when performing vm_object_page_remove().
the poll bits when there's actually something in the queue.
Otherwise, select always returned '2' when there were no items to be
read, and '3' when there were. This would preclude being able to read
in a threaded (libc_r) program, as well as checking to see if there
were pending events or not.
