in the arm __swp() and sparc64 casa() and casax() functions is actually
being used as an input and output and not just the value of the register
that points to the memory location. This was the underlying source of
the mbuf refcount problems on sparc64 a while back. For arm this should be
a nop because __swp() has a constraint to clobber all memory which can
probably be removed now.
Reviewed by: alc, cognet
MFC after: 1 week
SpitFire erratum #54) which can cause writes to the TICK_CMPR register
to fail. This seems to fix the dying clocks problem reported by jhb@
and kris@. [1]
- In tick_start() don't reset the tick counter of the boot processor to
zero. It's initially reset in _start() and afterwards but _before_
tick_start() is called on the BSP the APs synchronise with the tick
counter of the BSP in mp_startup(). Resetting the tick counter of the
BSP in tick_start() probably also was the cause of problems seen when
using the CPU tick counter as timecounter on SMP machines.
Not resetting the tick counter of the BSP in mp_startup() makes the
tick counters and tick interrupts between the BSP and APs be pretty
much in sync as it's supposed to be. This also means there's no longer
a real reason to have separate tick_start() and tick_start_ap() so
merge them and zap tick_start_ap(). This is also a first step in
simplifying the interface to the tick counters in preparation to use
alternate clock hardware where available.
- Switch to the algorithm used on FreeBSD/ia64 for updating the tick
interrupt register and which compensates the clock drift caused by
varying delays between when the tick interrupts actually trigger and
when they are serviced. Not compensating the clock drift mainly hurts
interactive performance especially when using WITNESS. [2]
For further information about the algorithm also see the commit log
of sys/ia64/ia64/interrupt.c rev. 1.38.
On sparc64 the sysctls for monitoring the behaviour of the tick
interrupts are machdep.tick.adjust_edges, machdep.tick.adjust_excess,
machdep.tick.adjust_missed and machdep.tick.adjust_ticks.
- In tick_init() just use tick_stop() for stopping the tick interrupts
until a proper handler is set up later. This also stops the system
tick interrupt on USIII systems earlier.
- In tick_start() check for a rough upper limit of HZ.
- Some minor changes, e.g. use FBSDID, remove unused headers, etc.
Info obtained from: Linux [1]
Ok'ed by: marcel [2]
Additional testing by: kris (earlier version of the workaround), jhb
X-MFC after: 3 days [1]
data access errors when trying to read/write to non-existant PCI devices.
fix the psycho bridge to use peek for probing devices. This no longer
fakes it if the OFW node doesn't exist (and the reg == 0).
Reviewed by: jake, tmm
These are called through function pointers so that different implementations
can be provided for cheetah, where the block load instructions may or may
not be a win, and so they can be disabled with the machdep.use_vis tunable.
In terms of raw bandwidth the integer versions are faster, but not allocating
lines in the L2 cache for useless data gives a measurable improvement in user
time for the benchmarks I tested (mostly buildworld with -j8).
As far as I can tell the instructions used are implemented on everything
back to UltraSPARC I, so there should not be a problem with different cpu
types.
can do 64 bytes at a time and don't allocate lines in the L2 cache. These
assume that everything is 64 byte aligned, and that there's more than 128
bytes of data (best for whole pages). The block load and store instructions
don't follow normal memory ordering rules and require either a memory barrier
or move between registers before the data can actually be used. This
implementation correctly shuffles around 3 out of the 4 sets of registers
in order to avoid memory barriers expect for the last 2 blocks.
and cpu_critical_exit() and moves associated critical prototypes into their
own header file, <arch>/<arch>/critical.h, which is only included by the
three MI source files that need it.
Backout and re-apply improperly comitted syntactical cleanups made to files
that were still under active development. Backout improperly comitted program
structure changes that moved localized declarations to the top of two
procedures. Partially re-apply one of the program structure changes to
move 'mask' into an intermediate block rather then in three separate
sub-blocks to make the code more readable. Re-integrate bug fixes that Jake
made to the sparc64 code.
Note: In general, developers should not gratuitously move declarations out
of sub-blocks. They are where they are for reasons of structure, grouping,
readability, compiler-localizability, and to avoid developer-introduced bugs
similar to several found in recent years in the VFS and VM code.
Reviewed by: jake
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
disable interrupts completely, and stxa_sync(), which performs a store
immediately followed by a membar #Sync with interrupts disabled (this
is needed for writes to diagnostic registers).
- The MD functions critical_enter/exit are renamed to start with a cpu_
prefix.
- MI wrapper functions critical_enter/exit maintain a per-thread nesting
count and a per-thread critical section saved state set when entering
a critical section while at nesting level 0 and restored when exiting
to nesting level 0. This moves the saved state out of spin mutexes so
that interlocking spin mutexes works properly.
- Most low-level MD code that used critical_enter/exit now use
cpu_critical_enter/exit. MI code such as device drivers and spin
mutexes use the MI wrappers. Note that since the MI wrappers store
the state in the current thread, they do not have any return values or
arguments.
- mtx_intr_enable() is replaced with a constant CRITICAL_FORK which is
assigned to curthread->td_savecrit during fork_exit().
Tested on: i386, alpha
space from kernel space and from an alternate address space to kernel
space.
2. Remove the unused and unprototyped physcopy() and physzero() and replace
with the more versatile ascopy() and aszero(), inspired by the above.
These can be used to copy and zero physical pages of memory without mapping
them into kernel space first.
3. Use magic numbers for the offsets in the jmpbuf structure like other
platforms.
4. Use SET.
Submitted by: tmm (1, 4)
- mostly complete kernel pmap support, and tested but currently turned
off userland pmap support
- low level assembly language trap, context switching and support code
- fully implemented atomic.h and supporting cpufunc.h
- some support for kernel debugging with ddb
- various header tweaks and filling out of machine dependent structures
to a new architecture. This is the base of the sparc64 port, but contains
limited machine dependent code, and can be used a base for ports. Included
are:
- standard machine dependent headers, tweaked for a 64 bit, big endian
architecture, including empty versions of all the machine dependent
structures
- a machine independent atomic.h, which can be used until a port has
support for interrupts and the operations really need to be atomic
- stub versions of all the machine dependent functions, which panic
when called and print out the name of the function that needs to
be implemented. functions which are normally in assembly files are
not included, but this should reduce the number of different undefined
references on the first few compiles from hundreds to 5 or 6
Given minimal startup code and console support it should be trivial to
make this compile and run the first few sysinits on almost any architecture.
Requested by: alfred, imp, jhb
