critical_enter() and critical_exit() are now solely a mechanism for
deferring kernel preemptions. They no longer have any affect on
interrupts. This means that standalone critical sections are now very
cheap as they are simply unlocked integer increments and decrements for the
common case.
Spin mutexes now use a separate KPI implemented in MD code: spinlock_enter()
and spinlock_exit(). This KPI is responsible for providing whatever MD
guarantees are needed to ensure that a thread holding a spin lock won't
be preempted by any other code that will try to lock the same lock. For
now all archs continue to block interrupts in a "spinlock section" as they
did formerly in all critical sections. Note that I've also taken this
opportunity to push a few things into MD code rather than MI. For example,
critical_fork_exit() no longer exists. Instead, MD code ensures that new
threads have the correct state when they are created. Also, we no longer
try to fixup the idlethreads for APs in MI code. Instead, each arch sets
the initial curthread and adjusts the state of the idle thread it borrows
in order to perform the initial context switch.
This change is largely a big NOP, but the cleaner separation it provides
will allow for more efficient alternative locking schemes in other parts
of the kernel (bare critical sections rather than per-CPU spin mutexes
for per-CPU data for example).
Reviewed by: grehan, cognet, arch@, others
Tested on: i386, alpha, sparc64, powerpc, arm, possibly more
and wd80x3 support. Make the obscure ISA cards optional, and add
those options to NOTES on i386 (note: the ifdef around the whole code
is for module building). Tweak pc98 ed support to include wd80x3 too.
Add goo for alpha too.
The affected cards are the 3Com 3C503, HP LAN+ and SIC (whatever that
is). I couldn't find any of these for sale on ebay, so they are
untested. If you have one of these cards, and send it to me, I'll
ensure that you have no future problems with it...
Minor cleanups as well by using functions rather than cut and paste
code for some probing operations (where the function call overhead is
lost in the noise).
Remove use of kvtop, since they aren't required anymore. This driver
needs to get its memory mapped act together, however, and use bus
space. It doesn't right now.
This reduces the size of if_ed.ko from about 51k to 33k on my laptop.
their own directory and module, leaving the MD parts in the MD
area (the MD parts _are_ part of the modules). /dev/mem and /dev/io
are now loadable modules, thus taking us one step further towards
a kernel created entirely out of modules. Of course, there is nothing
preventing the kernel from having these statically compiled.
This should allow us to more easily break out the acpi and 'legacy pc'
front ends as well (so only the bus front end would touch rtc, for
example).
This isn't a great separation, since isa dma routines are still called
from the MI code, but it is a start.
repocopied. Soon there will be additional bus attachments and
specialization for isa, acpi and pccard (and maybe pc98's cbus).
This was approved by nate, joerg and myself. bde dissented on the new
location, but appeared to be OK after some discussion.
of what uart(4) is and/or is not see the initial commit log of one
of the files in sys/dev/uart (or see share/man/man4/uart.4).
Note that currently pc98 shares the MD file with i386. This needs
to change when pc98 support is fleshed-out to properly support the
various UARTs. A good example is sparc64 in this respect.
We build uart(4) as a module on all platforms. This may break
the ppc port. That depends on whether they do actually build
modules.
To use uart(4) on alpha, one must use the NO_SIO option.
- Move isa/ppc* to sys/dev/ppc (repo-copy)
- Add an attachment method to ppc for puc
- In puc we need to walk the chain of parents.
Still to do, is to make ppc(4) & puc(4) work on other platforms. Testers
wanted.
PR: 38372 (in spirit done differently)
Verified by: Make universe (if I messed up a platform please fix)
for the agp module, and add agp to the list of modules to compile for alpha.
Add an alpha_mb() to agp_flush_cache for alpha -- it's not correct but may
improve the situation, and it's what linux and NetBSD do.
NB: But it will enable it in all kernels not having options "NO_GEOM"
Put the GEOM related options into the intended order.
Add "options NO_GEOM" to all kernel configs apart from NOTES.
In some order of controlled fashion, the NO_GEOM options will be
removed, architecture by architecture in the coming days.
There are currently three known issues which may force people to
need the NO_GEOM option:
boot0cfg/fdisk:
Tries to update the MBR while it is being used to control
slices. GEOM does not allow this as a direct operation.
SCSI floppy drives:
Appearantly the scsi-da driver return "EBUSY" if no media
is inserted. This is wrong, it should return ENXIO.
PC98:
It is unclear if GEOM correctly recognizes all variants of
PC98 disklabels. (Help Wanted! I have neither docs nor HW)
These issues are all being worked.
Sponsored by: DARPA & NAI Labs.
nearly in its entirety from i386, so it retains the phk/nati copyright.
Savecore likes the results, but I have no way to test it as gdb is
still broken.
disablement assumptions in kern_fork.c by adding another API call,
cpu_critical_fork_exit(). Cleanup the td_savecrit field by moving it
from MI to MD. Temporarily move cpu_critical*() from <arch>/include/cpufunc.h
to <arch>/<arch>/critical.c (stage-2 will clean this up).
Implement interrupt deferral for i386 that allows interrupts to remain
enabled inside critical sections. This also fixes an IPI interlock bug,
and requires uses of icu_lock to be enclosed in a true interrupt disablement.
This is the stage-1 commit. Stage-2 will occur after stage-1 has stabilized,
and will move cpu_critical*() into its own header file(s) + other things.
This commit may break non-i386 architectures in trivial ways. This should
be temporary.
Reviewed by: core
Approved by: core
device drivers for bus system with other endinesses than the CPU (using
interfaces compatible to NetBSD):
- bwap16() and bswap32(). These have optimized implementations on some
architectures; for those that don't, there exist generic implementations.
- macros to convert from a certain byte order to host byte order and vice
versa, using a naming scheme like le16toh(), htole16().
These are implemented using the bswap functions.
- stream bus space access functions, which do not perform a byte order
conversion (while the normal access functions would if the bus endianess
differs from the CPU endianess).
htons(), htonl(), ntohs() and ntohl() are implemented using the new
functions above for kernel usage. None of the above interfaces is currently
exported to user land.
Make use of the new functions in a few places where local implementations
of the same functionality existed.
Reviewed by: mike, bde
Tested on alpha by: mike
sio_pccard_detach to use new siodetach. Add an extra arg to sioprobe
to tell driver to probe/not probe the device for IRQs.
This incorporates most of Bruce's review material. I'm at a good
checkpoint, but there will be more to come based on bde's further
reviews.
Reviewed by: bde
Move sio from isa/sio.c to dev/sio/sio.c. The next step is to break
out the front end attachments, improve support for these parts on
different busses, and maybe, if we're lucky, merging in pc98 support.
It will also be MI and live in conf/files rather than files.*.
Approved by: bde
Tested with: i386, pc98
the cwd is looked up inside the kernel. The native getcwd() in libc
handles this in userland if __getcwd() fails.
Obtained from: NetBSD via OpenBSD
Tested by: Chris Casey <chriss@phys.ksu.edu>, Markus Holmberg <markush@acc.umu.se>
Reviewed by: Darrell Anderson <anderson@cs.duke.edu>
PR: kern/24315
- Replace some very poorly thought out API hacks that should have been
fixed a long while ago.
- Provide some much more flexible search functions (resource_find_*())
- Use strings for storage instead of an outgrowth of the rather
inconvenient temporary ioconf table from config(). We already had a
fallback to using strings before malloc/vm was running anyway.
