This is part of a long-term goal of merging Book-E and AIM into a single GENERIC
kernel. As more work is done, the struct may be optimized further.
Reviewed by: nwhitehorn
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
this change is to improve concurrency:
- Drop global state stored in the shadow overflow page table (and all other
global state)
- Remove all global locks
- Use per-PTE lock bits to allow parallel page insertion
- Reconstruct state when requested for evicted PTEs instead of buffering
it during overflow
This drops total wall time for make buildworld on a 32-thread POWER8 system
by a factor of two and system time by a factor of three, providing performance
20% better than similarly clocked Core i7 Xeons per-core. Performance on
smaller SMP systems, where PMAP lock contention was not as much of an issue,
is nearly unchanged.
Tested on: POWER8, POWER5+, G5 UP, G5 SMP (64-bit and 32-bit kernels)
Merged from: user/nwhitehorn/ppc64-pmap-rework
Looked over by: jhibbits, andreast
MFC after: 3 months
Relnotes: yes
Sponsored by: FreeBSD Foundation
available on firmwares 3.15 and earlier.
Caveats: Support for the internal SATA controller is currently missing,
as is support for framebuffer resolutions other than 720x480. These
deficiencies will be remedied soon.
Special thanks to Peter Grehan for providing the hardware that made this
port possible, and thanks to Geoff Levand of Sony Computer Entertainment
for advice on the LV1 hypervisor.
