modify vendor code (libuwx) with a specific include directive.
The second order advantage is that we can also enable verbosity
in the glue code (ia64/ia64/unwind.c).
(mainly the 3Com 3c996B/BCM5701).
For some reason that I don't fully understand, the 5701 signals PCS
encoding errors as though they were link change events, i.e. the 'link
state changed' bit in the status word of the status block is updated
and an interrupt is generated. This would cause the bge_tick() function
to be invoked and a "gigabit link up" message to be printed on the console.
To avoid this, the interrupt handler now checks the MAC status register
when a link change interrupt is triggered, and it will only call the
bge_tick() function if the 'PCS encoding error detected' bit is clear.
(This change should have no effect on copper NICs since this bit can
only ever be set in TBI mode. I do not know how it affects 5704 NICs
with a BCM8002 SERDES PHY.)
Special thanks to: Sherry Rogers at UCB for allowing me access to one
of their traffic monitor boxes so I could diagnose this problem.
compilation accordingly. The net effect is that tracing is not by
default present and that it can easily be compiled-in.
The tracer uses getenv() and printf(), which cannot be used in all
cases (ie from the debugger) and with this change we improved the
applicability of the unwinder.
This change is made on the vendor branch and given back to the
vendor for possible inclusion in future versions.
immediately after the kernel map has been sized, and is
the optimal place for the autosizing of memory allocations
which occur within the kernel map to occur.
Suggested by: bde
without Giant held.
A quick outline of the locking strategy:
Since all IOMMUs are synchronized, there is a single lock, iommu_mtx,
which protects the hardware registers (where needed) and the global and
per-IOMMU software states. As soon as the IOMMUs are divorced, each struct
iommu_state will have its own mutex (and the remaining global state
will be moved into the struct).
The dvma rman has its own internal mutex; the TSB slots may only be
accessed by the owner of the corresponding resource, so neither needs
extra protection.
Since there is a second access path to maps via LRU queues, the consumer-
provided locking is not sufficient; therefore, each map which is on a
queue is additionally protected by iommu_mtx (in part, there is one
member which only the map owner may access). Each map on a queue may
be accessed and removed from or repositioned in a queue in any context as
long as the lock is held; only the owner may insert a map.
To reduce lock contention, some bus_dma functions remove the map from
the queue temporarily (on behalf of the map owner) for some operations and
reinsert it when they are done. Shorter operations and operations which are
not done on behalf of the lock owner are completely covered by the lock.
To facilitate the locking, reorganize the streaming buffer handling;
while being there, fix an old oversight which would cause the streaming
buffer to always be flushed, regardless of whether streaming was enabled
in the TSB entry. The streaming buffer is still disabled for now, since
there are a number of drivers which lack critical bus_dmamp_sync() calls.
Additional testing by: jake
