PR #591 defines the rationale for kernel-level timers. They're most
immediately useful for TCP retransmission, but will most likely see use
in many other areas as well.
This patch introduces three separate thread queues, one for each thread
priority available to userspace (Low, Normal and High.)
Each queue operates in a round-robin fashion, but we now always prefer
to schedule the highest priority thread that currently wants to run.
There are tons of tweaks and improvements that we can and should make
to this mechanism, but I think this is a step in the right direction.
This makes WindowServer significantly more responsive while one of its
clients is burning CPU. :^)
The tool currently supports drawing an elliptical line of a specified
thickness. Further improvements can include adding a fill mode, and
holding down shift to draw a perfect circle.
Closes#375.
This functon will draw an ellipse which is intersecting the corners of
the rect given. It is a very naive implementation, taking 200 samples of
points around the ellipse, and drawing straight lines between each of
these points.
The ellipses look good enough to me though!
We don't care about dead processes that were once members of a specific
process group.
This was causing us to try and send SIGINT to already-dead processes
when pressing Ctrl+C in a terminal whose pgrp they were once in.
Fixes#922.
WindowServer will now send out a WindowStateChanged message to clients
when one of their windows is minimized.
This is then forwarded to the GWindow, which will try to mark its
underlying window backing store as volatile.
This allows the kernel to steal the memory used by minimized windows
in case it starts running low. Very cool! :^)
Instead of panicking right away when we run out of physical pages,
we now try to find a PurgeableVMObject with some volatile pages in it.
If we find one, we purge that entire object and steal one of its pages.
This makes it possible for the kernel to keep going instead of dying.
Very cool. :^)
We were listing the total number of user/super pages as the number of
"available" pages in the system. This was then misinterpreted in the
SystemMonitor program and displayed wrong in the GUI.
Previously we assumed all hosts would have support for IA32_EFER.NXE.
This is mostly true for newer hardware, but older hardware will crash
and burn if you try to use this feature.
Now we check for support via CPUID.80000001[20].
Use a pthread_cond_t to have the ASMixer thread wait until a client has
connected and added a buffer queue to the "pending mixing" vector.
This solves the long-standing issue of the system "idling" at ~8% CPU.
This patch implements a simple version of the futex (fast userspace
mutex) API in the kernel and uses it to make the pthread_cond_t API's
block instead of busily sched_yield().
An arbitrary userspace address is passed to the kernel as a "token"
that identifies the futex and you can then FUTEX_WAIT and FUTEX_WAKE
that specific userspace address.
FUTEX_WAIT corresponds to pthread_cond_wait() and FUTEX_WAKE is used
for pthread_cond_signal() and pthread_cond_broadcast().
I'm pretty sure I'm missing something in this implementation, but it's
hopefully okay for a start. :^)
Make sure we always line up the "hole" in the progress bar with the
right side of the paint rect. This fixes a 1px wide glitch seen when
using a darker system theme.
