thing when changing the debugging options as part of head becoming a new
stable branch. It may also help people who for one reason or another want
to run head but don't want it slowed down by the debugging support.
Reviewed by: kib
Add some improvements in the idle table callbacks:
- Replace instances of manual assembly instruction "hlt" call
with halt() function calling.
- In cpu_idle_mwait() avoid races in check to sched_runnable() using
the same pattern used in cpu_idle_hlt() with the 'hlt' instruction.
- Add comments explaining the logic behind the pattern used in
cpu_idle_hlt() and other idle callbacks.
patch modifies makesyscalls.sh to prefix all of the non-compatibility
calls (e.g. not linux_, freebsd32_) with sys_ and updates the kernel
entry points and all places in the code that use them. It also
fixes an additional name space collision between the kernel function
psignal and the libc function of the same name by renaming the kernel
psignal kern_psignal(). By introducing this change now we will ease future
MFCs that change syscalls.
Reviewed by: rwatson
Approved by: re (bz)
improvements:
(1) Implement new model in previously missed at91 UART driver
(2) Move BREAK_TO_DEBUGGER and ALT_BREAK_TO_DEBUGGER from opt_comconsole.h
to opt_kdb.h (spotted by np)
(3) Garbage collect now-unused opt_comconsole.h
MFC after: 3 weeks
Approved by: re (bz)
accessible:
(1) Always compile in support for breaking into the debugger if options
KDB is present in the kernel.
(2) Disable both by default, but allow them to be enabled via tunables
and sysctls debug.kdb.break_to_debugger and
debug.kdb.alt_break_to_debugger.
(3) options BREAK_TO_DEBUGGER and options ALT_BREAK_TO_DEBUGGER continue
to behave as before -- only now instead of compiling in
break-to-debugger support, they change the default values of the
above sysctls to enable those features by default. Current kernel
configurations should, therefore, continue to behave as expected.
(4) Migrate alternative break-to-debugger state machine logic out of
individual device drivers into centralised KDB code. This has a
number of upsides, but also one downside: it's now tricky to release
sio spin locks when entering the debugger, so we don't. However,
similar logic does not exist in other device drivers, including uart.
(5) dcons requires some special handling; unlike other console types, it
allows overriding KDB's own debugger selection, so we need a new
interface to KDB to allow that to work.
GENERIC kernels in -CURRENT will now support break-to-debugger as long as
appropriate boot/run-time options are set, which should improve the
debuggability of BETA kernels significantly.
MFC after: 3 weeks
Reviewed by: kib, nwhitehorn
Approved by: re (bz)
temporary variable and check with if as TUNABLE_*_FETCH do not
alter values unless successfully found the tunable.
Reported by: jhb, bde
MFC after: 3 days
X-MFC with: r224516
Approved by: re (kib)
NFSCL, NFSD instead of NFSCLIENT, NFSSERVER since
NFSCL and NFSD are now the defaults. The client change is
needed for diskless configurations, so that the root
mount works for fstype nfs.
Reported by seanbru at yahoo-inc.com for i386/XEN.
Approved by: re (hrs)
memtesting, which can easily save seconds to minutes of boot time.
The tunable name is kept general to allow reusing the code in
alternate frameworks.
Requested by: many
Discussed on: arch (a while a go)
Obtained from: Sandvine Incorporated
Reviewed by: sbruno
Approved by: re (kib)
MFC after: 2 weeks
Back in 2009 I changed the ABI of the GIO_KEYMAP and PIO_KEYMAP ioctls
to support wide characters. I created a patch to add ABI compatibility
for the old calls, but I didn't get any feedback to that.
It seems now people are upgrading from 8 to 9 they experience this
issue, so add it anyway.
The code has definitely been broken for SCHED_ULE, which is a default
scheduler. It may have been broken for SCHED_4BSD in more subtle ways,
e.g. with manually configured CPU affinities and for interrupt devilery
purposes.
We still provide a way to disable individual CPUs or all hyperthreading
"twin" CPUs before SMP startup. See the UPDATING entry for details.
Interaction between building CPU topology and disabling CPUs still
remains fuzzy: topology is first built using all availble CPUs and then
the disabled CPUs should be "subtracted" from it. That doesn't work
well if the resulting topology becomes non-uniform.
This work is done in cooperation with Attilio Rao who in addition to
reviewing also provided parts of code.
PR: kern/145385
Discussed with: gcooper, ambrisko, mdf, sbruno
Reviewed by: attilio
Tested by: pho, pluknet
X-MFC after: never
NFS client (which I guess is no longer experimental). The fstype "newnfs"
is now "nfs" and the regular/old NFS client is now fstype "oldnfs".
Although mounts via fstype "nfs" will usually work without userland
changes, an updated mount_nfs(8) binary is needed for kernels built with
"options NFSCL" but not "options NFSCLIENT". Updated mount_nfs(8) and
mount(8) binaries are needed to do mounts for fstype "oldnfs".
The GENERIC kernel configs have been changed to use options
NFSCL and NFSD (the new client and server) instead of NFSCLIENT and NFSSERVER.
For kernels being used on diskless NFS root systems, "options NFSCL"
must be in the kernel config.
Discussed on freebsd-fs@.
device in /dev/ create symbolic link with adY name, trying to mimic old ATA
numbering. Imitation is not complete, but should be enough in most cases to
mount file systems without touching /etc/fstab.
- To know what behavior to mimic, restore ATA_STATIC_ID option in cases
where it was present before.
- Add some more details to UPDATING.
stack. It means that all legacy ATA drivers are disabled and replaced by
respective CAM drivers. If you are using ATA device names in /etc/fstab or
other places, make sure to update them respectively (adX -> adaY,
acdX -> cdY, afdX -> daY, astX -> saY, where 'Y's are the sequential
numbers for each type in order of detection, unless configured otherwise
with tunables, see cam(4)).
ataraid(4) functionality is now supported by the RAID GEOM class.
To use it you can load geom_raid kernel module and use graid(8) tool
for management. Instead of /dev/arX device names, use /dev/raid/rX.
MPERF MSRs are available. It was disabled in r216443. Remove the earlier
hack to subtract 0.5% from the calibrated frequency as DELAY(9) is little
bit more reliable now.
safer for i386 because it can be easily over 4 GHz now. More worse, it can
be easily changed by user with 'machdep.tsc_freq' tunable (directly) or
cpufreq(4) (indirectly). Note it is intentionally not used in performance
critical paths to avoid performance regression (but we should, in theory).
Alternatively, we may add "virtual TSC" with lower frequency if maximum
frequency overflows 32 bits (and ignore possible incoherency as we do now).
functions are implemented with CMPXCHG8B instruction where it is available,
i. e., all Pentium-class and later processors. Note this instruction is
also used for atomic_store_rel_64() because a simple XCHG-like instruction
for 64-bit memory access does not exist, unfortunately. If the processor
lacks the instruction, i. e., 80486-class CPUs, two 32-bit load/store are
performed with interrupt temporarily disabled, assuming it does not support
SMP. Although this assumption may be little naive, it is true in reality.
This implementation is inspired by Linux.
Introduce the AHB glue for Atheros embedded systems. Right now it's
hard-coded for the AR9130 chip whose support isn't yet in this HAL;
it'll be added in a subsequent commit.
Kernel configuration files now need both 'ath' and 'ath_pci' devices; both
modules need to be loaded for the ath device to work.
- entirely eliminate some calls to uio_yeild() as being unnecessary,
such as in a sysctl handler.
- move should_yield() and maybe_yield() to kern_synch.c and move the
prototypes from sys/uio.h to sys/proc.h
- add a slightly more generic kern_yield() that can replace the
functionality of uio_yield().
- replace source uses of uio_yield() with the functional equivalent,
or in some cases do not change the thread priority when switching.
- fix a logic inversion bug in vlrureclaim(), pointed out by bde@.
- instead of using the per-cpu last switched ticks, use a per thread
variable for should_yield(). With PREEMPTION, the only reasonable
use of this is to determine if a lock has been held a long time and
relinquish it. Without PREEMPTION, this is essentially the same as
the per-cpu variable.
Clear the padding when returning context to the usermode, for
MI ucontext_t and x86 MD parts.
Kernel allocates the structures on the stack, and not clearing
reserved fields and paddings causes leakage.
the original amd64 and i386 headers with stubs.
Rename (AMD64|I386)_BUS_SPACE_* to X86_BUS_SPACE_* everywhere.
Reviewed by: imp (previous version), jhb
Approved by: kib (mentor)
Passing a count of zero on i386 and amd64 for [I386|AMD64]_BUS_SPACE_MEM
causes a crash/hang since the 'loop' instruction decrements the counter
before checking if it's zero.
PR: kern/80980
Discussed with: jhb
functions, they are unused. Remove 'user' from npxgetuserregs()
etc. names.
For {npx,fpu}{get,set}regs(), always use pcb->pcb_user_save for FPU
context storage. This eliminates the need for ugly copying with
overwrite of the newly added and reserved fields in ucontext on i386
to satisfy alignment requirements for fpusave() and fpurstor().
pc98 version was copied from i386.
Suggested and reviewed by: bde
Tested by: pho (i386 and amd64)
MFC after: 1 week
contents of the ones that were not empty were stale and unused.
- Now that <machine/mutex.h> no longer exists, there is no need to allow it
to override various helper macros in <sys/mutex.h>.
- Rename various helper macros for low-level operations on mutexes to live
in the _mtx_* or __mtx_* namespaces. While here, change the names to more
closely match the real API functions they are backing.
- Drop support for including <sys/mutex.h> in assembly source files.
Suggested by: bde (1, 2)
work properly with single-stepping in a kernel debugger. Specifically,
these routines have always disabled interrupts before increasing the nesting
count and restored the prior state of interrupts after decreasing the nesting
count to avoid problems with a nested interrupt not disabling interrupts
when acquiring a spin lock. However, trap interrupts for single-stepping
can still occur even when interrupts are disabled. Now the saved state of
interrupts is not saved in the thread until after interrupts have been
disabled and the nesting count has been increased. Similarly, the saved
state from the thread cannot be read once the nesting count has been
decreased to zero. To fix this, use temporary variables to store interrupt
state and shuffle it between the thread's MD area and the appropriate
registers.
In cooperation with: bde
MFC after: 1 month
