Sixty-five headers sat side by side in include/, so `#include "irq.h"`
said nothing about where irq.h was or what it belonged to, and errno.h,
stat.h and fcntl.h at the top shadowed the system's for any host tool
built with -I./include. They are in folders now -- arch/ core/ fs/
dev/ gfx/ net/ uapi/ (and ldls/ for the Linux driver layer) -- and
every include names the folder, as Linux's do: "core/proc.h".
Done mechanically and checked the hard way: the kernel built from this
tree disassembles identically to the one built from the tree before
it. The full image boots, and userland is the same set of programs.
Paths in docs and comments follow; docs/guides/layout.md has a table
of what is where, and tools/fix-includes.py rewrites old-style
includes from the folders in the tree, for code written before this.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01S1giNvrHTrPMPw7V6x1kQ4
`make ramroot` wiped the objects on the way in, and nothing wiped on the
way out. So a plain `make` afterwards kept every RAMDISK_ROOT object and
linked the 24 MB ramdisk back into a kernel that no longer used it: 25 MB
where a clean build is 836 KB. It still booted -- from the ramdisk -- and
the only outward symptom was stage2 having thirty times as much to load
through PIO, one sector at a time. That is the "booting got slower"
report this came from.
A stamp file records which setting the objects were built with, and the
tree is dropped when it changes in either direction.
qemu-kvm is opt-in and the default stays TCG, because the suite's timings
were established there. Measured with the guest timing itself,
`ls /bin | wc -l` goes 2.9s -> 1.1s. Boot does not improve and gets
slightly worse: every PIO port access in stage2 is a VM exit under KVM.
Retracts a claim from earlier today. The "2.2x speedup" attributed to the
region-based allocator was a measurement artifact -- the probe sent a
command, slept a fixed 50s on the host, then read /proc/uptime, so it
timed the sleep rather than the command, through a guest clock that drifts
under load. Bracketing the command inside one guest command line shows no
measurable difference. The e820 change is still correct; it is simply not
a performance change.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Records the four bugs between "boots to cpu0: starting" and "boots to an
interactive shell", the new ioremap rule for device registers, and what
the disc now contains -- including that it is still not a live CD, and
what that would take.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Records the measured effect of the region-based allocator (2.2x on a cold
ls, 6 s off the boot), the two pre-existing UEFI blockers found while
verifying it, and the three confounds that each produced a confident
wrong answer about guest speed in one session.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
