- Disable interrupt when updating compare value in order to
make this operation atomical
- Increase minimum period for event timer. Systimer on BCM2835
is compare timer, so if minimum period is too small it might
be less then fraction of time between "read current value" and
"set compare timer" operations. It means that when timer is armed
actual counter value is more then compare value and it will take
whole cycle (~32sec for 1MHz timer) to fire interrupt.
Submitted by: Daisuke Aoyama <aoyama at peach.ne.jp>
signal bug_ring ownership. However, instructions can be reordered
around members write leading to stale values for ie. br_prod_bufs.
Use correct memory barriers to ensure proper ordering of the
ownership tokens updates.
Sponsored by: EMC / Isilon storage division
MFC after: 2 weeks
typically do not handle the SYNCHRONIZE_CACHE command - they either
return an error or the firmware enters a reset loop.
Reviewed by: hselasky
Approved by: rstone (co-mentor)
MFC after: 2 weeks
As pointed out by hselasky@, USB_IF_CSI is the wrong macro here since we want
to declare the device's interface class, subclass and protocol, not class,
subclass and driver info.
Follow-up to r244704.
PR: kern/174707
Approved by: glebius
MFC after: 1 week
case. There is no point in optimizing further the code and use a TRUE
litteral for a path that does heavyweight stuff anyway (like lock acq),
at the price of obfuscated code.
Use the appropriate check where necessary and remove a macro.
Sponsored by: EMC / Isilon storage division
MFC after: 3 days
to the current demotion factor instead of assigning it.
This allows external scripts to control demotion factor together
with kernel in a raceless manner.
all interested parties in case if interface flag IFF_UP has changed.
However, not only SIOCSIFFLAGS can raise the flag, but SIOCAIFADDR
and SIOCAIFADDR_IN6 can, too. The actual |= is done not in the protocol
code, but in code of interface drivers. To fix this historical layering
violation, we will check whether ifp->if_ioctl(SIOCSIFADDR) raised the
IFF_UP flag, and if it did, run the if_up() handler.
This fixes configuring an address under CARP control on an interface
that was initially !IFF_UP.
P.S. I intentionally omitted handling the IFF_SMART flag. This flag was
never ever used in any driver since it was introduced, and since it
means another layering violation, it should be garbage collected instead
of pretended to be supported.
- Use spinlock_enter()/spinlock_exit() to prevent a thread holding a
debug lock from being preempted to prevent other threads waiting
on that lock from starvation.
- Handle the possibility of CPU migration in between the fetch of curcpu
and the call to spinlock_enter() by saving curcpu in a local variable.
- Use memory barriers to prevent reordering of loads and stores of the
data protected by the lock outside of the critical section
- Eliminate false sharing of the locks by moving them into the structures
that they protect and aligning them to a cacheline boundary.
- Record the owning thread in the lock to make debugging future problems
easier.
Reviewed by: rpaulo (initial version)
MFC after: 2 weeks
'"'. Mangling is only done for label names read from file system
metadata. Encoding resembles URL encoding. For example, the space
character becomes %20.
Help by: kib
Discussed with: imp, kib, pjd
interrupt context can still be idlethread. At that point, without the
panic condition, it can still happen that idlethread then will try to
acquire some locks to carry on some operations.
Skip the idlethread check on block/sleep lock operations when KDB is
active.
Reported by: jh
Tested by: jh
MFC after: 1 week
processing. For if_transmit() style hardware drivers (which none publicly
exist yet, for wireless) they will need to still implement if_start()
but only to re-start the TX queue.
allocate a map or mapping resources. That seems to imply that any memory
allocations it does must use M_NOWAIT and check for NULL.
Submitted by: Ian Lepore <freebsd@damnhippie.dyndns.org>
elements to the USB audio softc structure. This fixes a double CPU
fault when attaching USB audio devices in 10-current for i386 at
least.
MFC after: 1 week
Use a boundary of zero, hence a PAGE_SIZE boundary
is implied by all memory allocations.
Background:
Busdma has problems to allocate more than PAGE_SIZE
bytes when the boundary is PAGE_SIZE bytes too.
Initially it was thought that a boundary of PAGE_SIZE
bytes will only affect loading of DMA memory, so that
segments get split correctly, but it also affects
allocation of DMA'able memory.
Solution:
USB can detect big segments and split them as required
by the USB code.
MFC after: 1 week
Reported by: gonzo
When kern_yield() was introduced with the possibility to specify
a new priority, the behaviour changed by not lowering priority at all
in the consumers, making the yielding mechanism highly ineffective for
high priority kthreads like bufdaemon, syncer, vlrudaemon, etc.
There are no evidences that consumers could bear with such change in
semantic and this situation could finally lead to bugs similar to the
ones fixed in r244240.
Re-specify userland pri for kthreads involved.
Tested by: pho
Reviewed by: kib, mdf
MFC after: 1 week
previous names, 'ptag' and 'pmap' -- p stands for packet.
This change reduces the difference between the code in stable/9
and head, and also helps using the same ixgbe_netmap.h on both branches.
Approved by: Jack Vogel
through the USB API and/or busdma.
The following assumptions have been made:
umass - buffers passed from CAM/SCSI layer are OK
network - mbufs are OK.
Some other nits while at it.
MFC after: 1 week
Suggested by: imp
