Nexoniarz
bbc512a51c
time: read the clock from the TSC, not from counting interrupts ...
A timer interrupt that arrives while interrupts are disabled is not delayed,
it is lost -- the LAPIC in periodic mode holds one pending interrupt and drops
the rest. So anything the kernel does with interrupts off for longer than
10 ms makes `ticks` run slow, and it never catches up.
That has now presented twice as "uptime is wrong": once as an interrupt storm
taking 83% of the CPU, once as heavy console output on a display that is
expensive to draw to. Both times the tick was the messenger, and both times it
looked like a timekeeping bug.
monotonic() reads the TSC instead. It is a counter in the silicon that
advances whether or not this kernel is paying attention, it is already
measured against the PIT at boot, and reading it is one instruction and no
lock. wallclock(), /proc/uptime, sysinfo, getrusage and times() all go through
it now.
`ticks` keeps the job it is good at -- the scheduler preempts on it, sleep()
counts it -- where losing one means a slightly longer sleep rather than a
wrong answer about what time it is.
Lost ticks are no longer harmful, which makes them invisible, which is worse.
So /proc/interrupts now says
timer: 3383 ticks taken, 3387 expected
and names the gap when it grows, because a machine dropping timer interrupts
is spending too long with interrupts disabled, and that is worth knowing
before it turns into a clock that lies.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VQ7Qx8E1q1M1bbCq8QLHS2
2026-09-13 13:57:26 +02:00
Initial commit: Schunix as it stands before the SchOS rename
2026-08-09 13:47:01 +02:00
Raise the disk ceiling: 64-bit blocks, no FSSIZE panic, LBA48
2026-08-10 18:50:31 +02:00
Initial commit: Schunix as it stands before the SchOS rename
2026-08-09 13:47:01 +02:00
Initial commit: Schunix as it stands before the SchOS rename
2026-08-09 13:47:01 +02:00
time: read the clock from the TSC, not from counting interrupts
2026-09-13 13:57:26 +02:00
docs: four directories, and a rule for when a thing leaves the roadmap
2026-09-12 17:13:35 +02:00
Initial commit: Schunix as it stands before the SchOS rename
2026-08-09 13:47:01 +02:00
Initial commit: Schunix as it stands before the SchOS rename
2026-08-09 13:47:01 +02:00
Initial commit: Schunix as it stands before the SchOS rename
2026-08-09 13:47:01 +02:00
schfs: a format version policy, and refusing is not falling back
2026-09-12 17:13:59 +02:00
Rename Schunix to SchOS; the kernel becomes SchIFT
2026-08-09 14:09:59 +02:00
Rename Schunix to SchOS; the kernel becomes SchIFT
2026-08-09 14:09:59 +02:00
fs: devtmpfs, so /dev is generated rather than written to a disk
2026-09-12 20:18:30 +02:00
Rename Schunix to SchOS; the kernel becomes SchIFT
2026-08-09 14:09:59 +02:00
init survives stray signals; commands are 4-34x faster
2026-08-09 15:54:05 +02:00
fs: timestamps come from the clock, and /proc/fsstat says how full the tables are
2026-09-12 17:14:14 +02:00
tty: six virtual terminals, and the plumbing that makes them terminals
2026-09-13 00:08:00 +02:00
usb-hid: bind an absolute pointer, and plumb EV_ABS through
2026-08-10 18:27:01 +02:00
Initial commit: Schunix as it stands before the SchOS rename
2026-08-09 13:47:01 +02:00
tty: AltGr+F1..F6 by default, and AltGr+-/+ to step
2026-09-13 13:22:01 +02:00
docs: a branding folder, and the three marks are not interchangeable
2026-09-12 18:19:09 +02:00
Free every usable memory region, not one contiguous run
2026-08-09 20:03:51 +02:00
Initial commit: Schunix as it stands before the SchOS rename
2026-08-09 13:47:01 +02:00
Initial commit: Schunix as it stands before the SchOS rename
2026-08-09 13:47:01 +02:00
net: a frame wakes the stack, instead of waiting for the clock
2026-09-12 17:23:46 +02:00
kernel: processes have an environment now, and zsh is the shell
2026-09-12 23:26:50 +02:00
net: a network *class*, so the stack stops knowing what an e1000 is
2026-08-15 16:42:34 +02:00
tty: the switch chord is a setting, because only the host knows the answer
2026-09-13 13:13:38 +02:00
tty: six virtual terminals, and the plumbing that makes them terminals
2026-09-13 00:08:00 +02:00
docs: four directories, and a rule for when a thing leaves the roadmap
2026-09-12 17:13:35 +02:00
boot/uefi: the memory map the kernel gets is the one the firmware agreed to
2026-08-11 11:42:22 +02:00
schfs: records at arbitrary offsets are packed, and the compiler is told
2026-09-12 17:56:36 +02:00
Initial commit: Schunix as it stands before the SchOS rename
2026-08-09 13:47:01 +02:00
net: AF_NETLINK, so getifaddrs() works for everything and not just one program
2026-09-12 19:23:34 +02:00
Initial commit: Schunix as it stands before the SchOS rename
2026-08-09 13:47:01 +02:00
Initial commit: Schunix as it stands before the SchOS rename
2026-08-09 13:47:01 +02:00
Initial commit: Schunix as it stands before the SchOS rename
2026-08-09 13:47:01 +02:00
Initial commit: Schunix as it stands before the SchOS rename
2026-08-09 13:47:01 +02:00
gfx: the console and the crash screen stop drawing on a driver by name
2026-08-15 17:04:10 +02:00
Initial commit: Schunix as it stands before the SchOS rename
2026-08-09 13:47:01 +02:00
Initial commit: Schunix as it stands before the SchOS rename
2026-08-09 13:47:01 +02:00
Initial commit: Schunix as it stands before the SchOS rename
2026-08-09 13:47:01 +02:00
Rename Schunix to SchOS; the kernel becomes SchIFT
2026-08-09 14:09:59 +02:00
usb-hid: bind an absolute pointer, and plumb EV_ABS through
2026-08-10 18:27:01 +02:00
kernel: processes have an environment now, and zsh is the shell
2026-09-12 23:26:50 +02:00
tty: AltGr+F1..F6 by default, and AltGr+-/+ to step
2026-09-13 13:22:01 +02:00
schfs: the commit barrier, reflink, and attributes with an index over them
2026-08-15 16:02:02 +02:00
bbc512a51c