correct, but unfortunately in trap.c trapsignal(p, SIGSEGV, code) passes
the address of the fault in code, instead of the trap code. So we punt for
now doing checking for trap code validity until this gets fixed.
helper functions. This cuts down the number of needless function calls
by approx. 80%, which has a healthy effect on the responsiveness of
a machine under heavy process creation/teardown loads.
The VM system seems to be fond of asking to delete page mappings
which aren't there..
the address of the desired PTE location is readily available in the
callers context (setpte4m() retraces the entire 3-level structure
to arrive at the PTE location).
Also, in many cases we can do away with the distinction between pmaps
that have or have not allocated a context. This is really only useful
in cases where we're interested in the REF or MOD bits which can differ
in the TLB version of a PTE. By doing this, we avoid getpte()'s which
in many cases instruct the MMU to start a table walk only to find out
that there's nothing there after going 2/3 of the way, or waste a TLB
entry because of TLB flushing soon after getpte() completes.
In addition, there's a hook to flush the cache line corresponding to
the (kernel virtual) location of a PTE entry when it gets altered.
allocate and initialize all kernel page tables before looking at the
PROM maps, which allows mmu_reservemon4m() to simply walk the PROM tables
without having to allocate bits and pieces of our own kernel tables.
Slightly optimize getcontext() macros in mutli-arch kernels.
Remove un-needed `4m' version of mmu_pagein().
Some of the stuff (e.g., rarpd, bootpd, dhcpd etc., libsa) still will
only support Ethernet. Tcpdump itself should be ok, but libpcap needs
lot of work.
For the detailed change history, look at the commit log entries for
the is-newarp branch.
pk