John Baldwin e0f66ef861 Reorganize the interrupt handling code a bit to make a few things cleaner ... 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)		2005-10-25 19:48:48 +00:00
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isa_dma.c
isa.c	Reorganize the interrupt handling code a bit to make a few things cleaner	2005-10-25 19:48:48 +00:00
isavar.h
mcclock_isa.c