and increase flexibility to allow various different approaches to be tried
in the future.
- Split struct ithd up into two pieces. struct intr_event holds the list
of interrupt handlers associated with interrupt sources.
struct intr_thread contains the data relative to an interrupt thread.
Currently we still provide a 1:1 relationship of events to threads
with the exception that events only have an associated thread if there
is at least one threaded interrupt handler attached to the event. This
means that on x86 we no longer have 4 bazillion interrupt threads with
no handlers. It also means that interrupt events with only INTR_FAST
handlers no longer have an associated thread either.
- Renamed struct intrhand to struct intr_handler to follow the struct
intr_foo naming convention. This did require renaming the powerpc
MD struct intr_handler to struct ppc_intr_handler.
- INTR_FAST no longer implies INTR_EXCL on all architectures except for
powerpc. This means that multiple INTR_FAST handlers can attach to the
same interrupt and that INTR_FAST and non-INTR_FAST handlers can attach
to the same interrupt. Sharing INTR_FAST handlers may not always be
desirable, but having sio(4) and uhci(4) fight over an IRQ isn't fun
either. Drivers can always still use INTR_EXCL to ask for an interrupt
exclusively. The way this sharing works is that when an interrupt
comes in, all the INTR_FAST handlers are executed first, and if any
threaded handlers exist, the interrupt thread is scheduled afterwards.
This type of layout also makes it possible to investigate using interrupt
filters ala OS X where the filter determines whether or not its companion
threaded handler should run.
- Aside from the INTR_FAST changes above, the impact on MD interrupt code
is mostly just 's/ithread/intr_event/'.
- A new MI ddb command 'show intrs' walks the list of interrupt events
dumping their state. It also has a '/v' verbose switch which dumps
info about all of the handlers attached to each event.
- We currently don't destroy an interrupt thread when the last threaded
handler is removed because it would suck for things like ppbus(8)'s
braindead behavior. The code is present, though, it is just under
#if 0 for now.
- Move the code to actually execute the threaded handlers for an interrrupt
event into a separate function so that ithread_loop() becomes more
readable. Previously this code was all in the middle of ithread_loop()
and indented halfway across the screen.
- Made struct intr_thread private to kern_intr.c and replaced td_ithd
with a thread private flag TDP_ITHREAD.
- In statclock, check curthread against idlethread directly rather than
curthread's proc against idlethread's proc. (Not really related to intr
changes)
Tested on: alpha, amd64, i386, sparc64
Tested on: arm, ia64 (older version of patch by cognet and marcel)
release) the sio spin mutex, as use of synchronization primitives in
the debugger can result in substantial problems. With this patch in
place entering the debugger via a serial console is made
substantially more reliable.
MFC after: 1 week
Tested by: kris
Discussed with: bde
happens because the sio device was never opened and com->tp is
therefore NULL. ttygone can't swallow a NULL, so guard against that
possibility. Other places in this function make similar checks, so I
believe this is correct.
future:
rename ttyopen() -> tty_open() and ttyclose() -> tty_close().
We need the ttyopen() and ttyclose() for the new generic cdevsw
functions for tty devices in order to have consistent naming.
it's in the way even more. Basicly: remove all alpha specific console
support from gfb(4), sio(4) and syscons(4). Rewrite the alpha console
initialization to be identical to all other platforms. In a nutshell:
call cninit().
The platform specific code now only sets or clears RB_SERIAL and thus
automaticly causes the right console to be selected.
sio.c:
o Replace the remote GDB hacks and use the GDB debug port interface
instead.
o Make debugging code conditional upon KDB instead of DDB.
o Call kdb_alt_break() instead of db_alt_break().
o Call kdb_enter() instead of breakpoint().
o Remove the ugly compatibility of using the console as the debug
port.
copies.
No current line disciplines have a dynamically changing hotchar, and
expecting to receive anything sensible during a change in ldisc is
insane so no locking of the hotchar field is necessary.
called ttyldoptim().
Use this function from all the relevant drivers.
I belive no drivers finger linesw[] directly anymore, paving the way for
locking and refcounting.
returns okay when HW probe fails. This happens when comconsole flag is
set but VGA console is used instead.
Back out requested by: bde (He will be looking at other solutions from scratch)
- Define option FORCECONSPEED to force the serial console to
be CONSPEED. I've run into a lot of boards in which
the detect for prior speed doesn't work and ends up with
broken console since it is at the wrong speed.
- If a serial port is marked as a console, but console=vidconsole
and if the serial ports doesn't exist it will be probed and
attached at a 8250 chip. Then writes to that will freeze the
system.
- Add an option flags 0x400000 to mark this as a potential
comconsole in-case the one flaged with 0x10 does not exist
in the system.
This makes it easier to deploy on systems with one or two serial ports.
Obtained from: IronPort
Introduce d_version field in struct cdevsw, this must always be
initialized to D_VERSION.
Flip sense of D_NOGIANT flag to D_NEEDGIANT, this involves removing
four D_NOGIANT flags and adding 145 D_NEEDGIANT flags.
Add missing D_TTY flags to various drivers.
Complete asserts that dev_t's passed to ttyread(), ttywrite(),
ttypoll() and ttykqwrite() have (d_flags & D_TTY) and a struct tty
pointer.
Make ttyread(), ttywrite(), ttypoll() and ttykqwrite() the default
cdevsw methods for D_TTY drivers and remove the explicit initializations
in various drivers cdevsw structures.
Free approx 86 major numbers with a mostly automatically generated patch.
A number of strategic drivers have been left behind by caution, and a few
because they still (ab)use their major number.
with multiple ports on a shared interrupt demultiplexed by the puc_intr()
handler.
siointr1() first read as much input as possible and then checked all
possibly-relevant status registers, partly for robustness and partly
for historical reasons. This is very bad if it is called for every
port sharing an interrupt like puc_intr() does. It can spend too long
reading all the input for some ports when the interrupt is for a more
urgent event on another, or just too long checking all the status
registers when there are lots of ports. The inter-character time is
too long for reading all the input even when the interrupt is for a
transmitter interrupt on the same port, and at 921600 bps the inter-char
time is 10.85 usec and was often exceeded with just 2 ports, leaving
the transmitters idle for about 6% of the time.
The tweak is to break out of the read loop after reading 1 char if
output can be done. This avoids most of the idle transmitter time for
2 active ports at 921600 bps bidirectional on the test system. It
also reduces overhead by about 20%. More complete fixes use the
programmable tx low watermark on 16950's and reduce overhead by another
65%.
will now need editing except for spot checks.
Changed this buffer from a circular one to a linear one. This is more
useful for some cases and the sysctl that prints it doesn't support
circular buffers.
Fixed (output) formatting bugs in this sysctl. An off by 1 error caused
a garbage byte to be returned after annotation of large deltas, and
a race with the writer sometimes caused premature string termination.
from fiddling with CS_TTGO since fiddling with CS_TTGO was removed in
rev.1.218 of the i386/isa version (which was merged with loss of history
in rev.1.223 of this version).
