>Description:
If a process attempts to open a floppy tape device when the
device has been configured in the kernel, but did not probe and attach
on bootup, then a panic will occur.
[Review: The current ft situation is a crock, and this only bandaids
an earlier wound inflicted by making the attach conditional. This urgently
requires a review]
Submitted by: gene
Change a round to a truncate. Problem reported from Christoph Kukulies:
9.8 2 / p did an IOT trap.
There is one remaining problem.: 9.8 2 % p shows on other machines 1.8
but does here in the moment 1.
file anymore after this. My link makes it too painful to make
interactive mods, and I don't have the CVS tree here so making changes
for "previous history" have to get done on freefall, with the corresponding
degree of pain.
Use the correct value of hz (stathz if it is nonzero) for
interpretion of dk_time[] and cp_time[] in iostat.c. Avoid
multiple conversions of this value in iostat.c and vmstat.c
iostat.c:
Implement the display of cp_time[CP_INTR]. Fix the display
of cp_time[CP_IDLE] (the display was always null because
cp_time[CP_INTR] == 0 was displayed instead).
systat.1:
Document the display of cp_time[CP_INTR].
vmstat.c:
Implement the display of cp_time[CP_INTR].
Keep track of interrupt nesting level. It is normally 0
for syscalls and traps, but is fudged to 1 for their exit
processing in case they metamorphose into an interrupt
handler.
i386/genassym.c;
Remove support for the obsolete pcb_iml and pcb_cmap2.
Add support for pcb_inl.
i386/swtch.s:
Fudge the interrupt nesting level across context switches and in
the idle loop so that the work for preemptive context switches
gets counted as interrupt time, the work for voluntary context
switches gets counted mostly as system time (the part when
curproc == 0 gets counted as interrupt time), and only truly idle
time gets counted as idle time.
Remove obsolete support (commented out and otherwise) for pcb_iml.
Load curpcb just before curproc instead of just after so that
curpcb is always valid if curproc is. A few more changes like
this may fix tracing through context switches.
Remove obsolete function swtch_to_inactive().
include/cpu.h:
Use the new interrupt nesting level variable to implement a
non-fake CLF_INTR() so that accounting for the interrupt state
works.
You can use top, iostat or (best) an up to date systat to see
interrupt overheads. I see the expected huge interrupt overheads
for ISA devices (on a 486DX/33, about 55% for an IDE drive
transferring 1250K/sec and the same for a WD8013EBT network card
transferring 1100K/sec). The huge interrupt overheads for serial
devices are unfortunately normally invisible.
include/pcb.h:
Remove the obsolete pcb_iml and pcb_cmap2. Replace them by
padding to preserve binary compatibility.
Use part of the new padding for pcb_inl.
isa/icu.s:
isa/vector.s:
Keep track of interrupt nesting level.
|Message-Id: <199412011713.JAA03374@timesink.spk.wa.us>
|To: jkh@whisker.hubbard.ie
|Subject: A little problem with MAKEDEV
|
|For a while now, MAKEDEV's been kinda neat: you create the cua* files,
|and it deletes the tty* files; you create the tty* files and it
|deletes the corresponding cua* files. K00l! :-)
[Ed Note - I think this behavior was wrong, and this fix better].
