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)
times which was added in the last revision with what should be a proper
solution as long as keyboards that were pluggged in after the kernel
has fully booted aren't supported. I.e. when sunkbd_configure() is
called for the high-level console probe make sure that the keyboard is
both successfully configured (i.e. also probed) and attached. The band-
aid left the possibility to attach the keyboard device to the high-level
console without attaching the keyboard device itself when the keyboard
is plugged in after uart(4) attached but before syscons(4) does.
a band-aid allowing to call this function savely multiple times, e.g.
during sckbdprobe() and sc_probe_unit(). Otherwise calling it a second
time results in a non-working keyboard. This needs a lot of more work
to actually do the right thing and work like expected.
- Let sunkbd_configure() return the number of the found keyboards, i.e.
1 in case probing succeeds, as it's expected. The return values of the
keyboard configure functions however currently aren't checked so this
doesn't make a difference at the moment.
- Use FBSDID.
The presence or absence of a keyboard does not change whether an
UART is designed as a keyboard port or not and thus whether we
can use the port as a TTY or not.
We now call sunkbd_attach() even when we didn't previously find
a keyboard. Emit a useful message stating that no keyboard was
found, but don't do anything else.
MFC after: 5 days
