all to date and the latter also is only used in ia64 and powerpc
code which no longer serves a real purpose after bring-up and just
can be removed as well. Note that architectures like sun4u also
provide no means of implementing IPI'ing a CPU itself natively
in the first place.
Suggested by: jhb
Reviewed by: arch, grehan, jhb
On the i386 architecture, the processor only saves the current value
of `%esp' on stack if a privilege switch is necessary when entering
the interrupt handler. Thus, `frame->tf_esp' is only valid for
an entry from user mode. For interrupts taken in kernel mode, we
need to determine the top-of-stack for the interrupted kernel
procedure by adding the appropriate offset to the current frame
pointer.
Reported by: kris, Fabien Thomas
Tested by: Fabien Thomas <fabien.thomas at netasq dot com>
the same vmspace, decrement the reference count of the shared LDT instead
of a newly-made copy. Code factually removed LDT from the process that
did rfork(0).
Introduce user_ldt_deref() function that does decrement of refcount for
the struct proc_ldt, and call it in the rfork(0) case on the shared LDT.
Reviewed by: jhb
MFC after: 1 week
- Rename pciereg_cfgopen() to pcie_cfgregopen() and expose it to the
rest of the kernel. It now also accepts parameters via function
arguments rather than global variables.
- Add a notion of minimum and maximum bus numbers and reject requests for
an out of range bus.
- Add more range checks on slot/func/reg/bytes parameters to the cfg reg
read/write routines. Don't panic on any invalid parameters, just fail
the request (writes do nothing, reads return -1). This matches the
behavior of the other cfg mechanisms.
- Port the memory mapped configuration space access to amd64. On amd64
we simply use the direct map (via pmap_mapdev()) for the memory mapped
window.
- During acpi_attach() just after loading the ACPI tables, check for a
MCFG table. If it exists, call pciereg_cfgopen() on each subtable
(memory mapped window). For now we only support windows for domain 0
that start with bus 0. This removes the need for more chipset-specific
quirks in the MD code.
- Remove the chipset-specific quirks for the Intel 5000P/V/Z chipsets
since these machines should all have MCFG tables via ACPI.
- Updated pci_cfgregopen() to DTRT if ACPI had invoked pcie_cfgregopen()
earlier.
MFC after: 2 weeks
features of CPUs like reading/writing machine-specific registers,
retrieving cpuid data, and updating microcode.
- Add cpucontrol(8) utility, that provides userland access to
the features of cpuctl(4).
- Add subsequent manpages.
The cpuctl(4) device operates as follows. The pseudo-device node cpuctlX
is created for each cpu present in the systems. The pseudo-device minor
number corresponds to the cpu number in the system. The cpuctl(4) pseudo-
device allows a number of ioctl to be preformed, namely RDMSR/WRMSR/CPUID
and UPDATE. The first pair alows the caller to read/write machine-specific
registers from the correspondent CPU. cpuid data could be retrieved using
the CPUID call, and microcode updates are applied via UPDATE.
The permissions are inforced based on the pseudo-device file permissions.
RDMSR/CPUID will be allowed when the caller has read access to the device
node, while WRMSR/UPDATE will be granted only when the node is opened
for writing. There're also a number of priv(9) checks.
The cpucontrol(8) utility is intened to provide userland access to
the cpuctl(4) device features. The utility also allows one to apply
cpu microcode updates.
Currently only Intel and AMD cpus are supported and were tested.
Approved by: kib
Reviewed by: rpaulo, cokane, Peter Jeremy
MFC after: 1 month
when stack realignment is turned on (it is ALWAYS on for main), however
in a profiling build %ecx would be clobbered by mcount(), this would lead
to a segmentation fault when the code tries to reference any argument.
This fix changes mcount() to preserve %ecx.
PR: bin/119709
Reviewed by: bde
MFC after: 1 week
Now that st_rdev is being automatically generated by the kernel, there
is no need to define static major/minor numbers for the iodev and
memdev. We still need the minor numbers for the memdev, however, to
distinguish between /dev/mem and /dev/kmem.
Approved by: philip (mentor)
from idle over the next tick.
- Add a new MD routine, cpu_wake_idle() to wakeup idle threads who are
suspended in cpu specific states. This function can fail and cause the
scheduler to fall back to another mechanism (ipi).
- Implement support for mwait in cpu_idle() on i386/amd64 machines that
support it. mwait is a higher performance way to synchronize cpus
as compared to hlt & ipis.
- Allow selecting the idle routine by name via sysctl machdep.idle. This
replaces machdep.cpu_idle_hlt. Only idle routines supported by the
current machine are permitted.
Sponsored by: Nokia
for better structure.
Much of this is related to <sys/clock.h>, which should really have
been called <sys/calendar.h>, but unless and until we need the name,
the repocopy can wait.
In general the kernel does not know about minutes, hours, days,
timezones, daylight savings time, leap-years and such. All that
is theoretically a matter for userland only.
Parts of kernel code does however care: badly designed filesystems
store timestamps in local time and RTC chips almost universally
track time in a YY-MM-DD HH:MM:SS format, and sometimes in local
timezone instead of UTC. For this we have <sys/clock.h>
<sys/time.h> on the other hand, deals with time_t, timeval, timespec
and so on. These know only seconds and fractions thereof.
Move inittodr() and resettodr() prototypes to <sys/time.h>.
Retain the names as it is one of the few surviving PDP/VAX references.
Move startrtclock() to <machine/clock.h> on relevant platforms, it
is a MD call between machdep.c/clock.c. Remove references to it
elsewhere.
Remove a lot of unnecessary <sys/clock.h> includes.
Move the machdep.disable_rtc_set sysctl to subr_rtc.c where it belongs.
XXX: should be kern.disable_rtc_set really, it's not MD.
1. Add support for automatic promotion of 4KB page mappings to 2MB page
mappings. Automatic promotion can be enabled by setting the tunable
"vm.pmap.pg_ps_enabled" to a non-zero value. By default, automatic
promotion is disabled. Tested by: kris
2. To date, we have assumed that the TLB will only set the PG_M bit in a
PTE if that PTE has the PG_RW bit set. However, this assumption does
not hold on recent processors from Intel. For example, consider a PTE
that has the PG_RW bit set but the PG_M bit clear. Suppose this PTE
is cached in the TLB and later the PG_RW bit is cleared in the PTE,
but the corresponding TLB entry is not (yet) invalidated.
Historically, upon a write access using this (stale) TLB entry, the
TLB would observe that the PG_RW bit had been cleared and initiate a
page fault, aborting the setting of the PG_M bit in the PTE. Now,
however, P4- and Core2-family processors will set the PG_M bit before
observing that the PG_RW bit is clear and initiating a page fault. In
other words, the write does not occur but the PG_M bit is still set.
The real impact of this difference is not that great. Specifically,
we should no longer assert that any PTE with the PG_M bit set must
also have the PG_RW bit set, and we should ignore the state of the
PG_M bit unless the PG_RW bit is set.
these days, so de-generalize the acquire_timer/release_timer api
to just deal with speakers.
The new (optional) MD functions are:
timer_spkr_acquire()
timer_spkr_release()
and
timer_spkr_setfreq()
the last of which configures the timer to generate a tone of a given
frequency, in Hz instead of 1/1193182th of seconds.
Drop entirely timer2 on pc98, it is not used anywhere at all.
Move sysbeep() to kern/tty_cons.c and use the timer_spkr*() if
they exist, and do nothing otherwise.
Remove prototypes and empty acquire-/release-timer() and sysbeep()
functions from the non-beeping archs.
This eliminate the need for the speaker driver to know about
i8254frequency at all. In theory this makes the speaker driver MI,
contingent on the timer_spkr_*() functions existing but the driver
does not know this yet and still attaches to the ISA bus.
Syscons is more tricky, in one function, sc_tone(), it knows the hz
and things are just fine.
In the other function, sc_bell() it seems to get the period from
the KDMKTONE ioctl in terms if 1/1193182th second, so we hardcode
the 1193182 and leave it at that. It's probably not important.
Change a few other sysbeep() uses which obviously knew that the
argument was in terms of i8254 frequency, and leave alone those
that look like people thought sysbeep() took frequency in hertz.
This eliminates the knowledge of i8254_freq from all but the actual
clock.c code and the prof_machdep.c on amd64 and i386, where I think
it would be smart to ask for help from the timecounters anyway [TBD].
- Add a new intr_event method ie_assign_cpu() that is invoked when the MI
code wishes to bind an interrupt source to an individual CPU. The MD
code may reject the binding with an error. If an assign_cpu function
is not provided, then the kernel assumes the platform does not support
binding interrupts to CPUs and fails all requests to do so.
- Bind ithreads to CPUs on their next execution loop once an interrupt
event is bound to a CPU. Only shared ithreads are bound. We currently
leave private ithreads for drivers using filters + ithreads in the
INTR_FILTER case unbound.
- A new intr_event_bind() routine is used to bind an interrupt event to
a CPU.
- Implement binding on amd64 and i386 by way of the existing pic_assign_cpu
PIC method.
- For x86, provide a 'intr_bind(IRQ, cpu)' wrapper routine that looks up
an interrupt source and binds its interrupt event to the specified CPU.
MI code can currently (ab)use this by doing:
intr_bind(rman_get_start(irq_res), cpu);
however, I plan to add a truly MI interface (probably a bus_bind_intr(9))
where the implementation in the x86 nexus(4) driver would end up calling
intr_bind() internally.
Requested by: kmacy, gallatin, jeff
Tested on: {amd64, i386} x {regular, INTR_FILTER}
different "platforms" on x86 machines. The existing code already handles
having two platforms: ACPI and legacy. However, the existing approach was
rather hardcoded and difficult to extend. These changes take the approach
that each x86 hardware platform should provide its own nexus(4) driver (it
can inherit most of its behavior from the default legacy nexus(4) driver)
which is responsible for probing for the platform and performing
appropriate platform-specific setup during attach (such as adding a
platform-specific bus device). This does mean changing the x86 platform
busses to no longer use an identify routine for probing, but to move that
logic into their matching nexus(4) driver instead.
- Make the default nexus(4) driver in nexus.c on i386 and amd64 handle the
legacy platform. It's probe routine now returns BUS_PROBE_GENERIC so it
can be overriden.
- Expose a nexus_init_resources() routine which initializes the various
resource managers so that subclassed nexus(4) drivers can invoke it from
their attach routine.
- The legacy nexus(4) driver explicitly adds a legacy0 device in its
attach routine.
- The ACPI driver no longer contains an new-bus identify method. Instead
it exposes a public function (acpi_identify()) which is a probe routine
that the MD nexus(4) drivers can use to probe for ACPI. All of the
probe logic in acpi_probe() is now moved into acpi_identify() and
acpi_probe() is just a stub.
- On i386 and amd64, an ACPI-specific nexus(4) driver checks for ACPI via
acpi_identify() and claims the nexus0 device if the probe succeeds. It
then explicitly adds an acpi0 device in its attach routine.
- The legacy(4) driver no longer knows anything about the acpi0 device.
- On ia64 if acpi_identify() fails you basically end up with no devices.
This matches the previous behavior where the old acpi_identify() would
fail to add an acpi0 device again leaving you with no devices.
Discussed with: imp
Silence on: arch@
PhysMask fields based on the number of physical address bits supported
by the current CPU. The old code assumed 36 bits on i386 and 40 bits on
amd64. In truth, all Intel CPUs up until recently used 36 bits (a newer
Intel CPU uses 38 bits) and all the Opteron CPUs used 40 bits.
In at least one case (the new Intel CPU) having the size of the mask field
wrong resulted in writing questionable values into the MTRR registers on
the application processors (BSP as well if you modify the MTRRs via
memcontrol or running X, etc.). The result of the questionable physmask
was that all of memory was apparently treated as uncached rather than
write-back resulting in a very significant performance hit.
Fix this by constructing a run-time mask for the PhysBase and PhysMask
fields based on the number of physical address bits supported by the CPU.
All 64-bit capable CPUs provide a count of PA bits supported via the
0x80000008 extended CPUID feature, so use that if it is available. If that
feature is not available, then assume 36 PA bits.
While I'm here, expand the (now-unused) macros for the PhysBase and
PhysMask fields to the current largest possible value (52 PA bits).
MFC after: 1 week
PR: i386/120516
Reported by: Nokia
expressions on i386 are evaluated in the range of the long double type,
so this is wrong in a different but hopefully less worse way than
before. Since expressions are evaluated in long double registers,
there is no runtime cost to using long double instead of double to
declare intermediate values (except in cases where this avoids compiler
bugs), and by careful use of float_t or double_t it is possible to
avoid some of the compiler bugs in this area, provided these types are
declared as long double.
I was going to change float.h to be less broken and more usable in
combination with the change here (in particular, it is more necessary
to know the effective number of bits in a double_t when double_t !=
double, since DBL_MANT_DIG no longer logically gives this, and
LDBL_MANT_DIG doesn't give it either with FreeBSD-i386's default
rounding precision. However, this was too hard for now. In particular,
LDBL_MANT_DIG is used a lot in libm, so it cannot be changed. One
thing that is completely broken now is LDBL_MAX. This may have sort
of worked when it was changed from DBL_MAX in 2002 (adding 0 to it at
runtime gave +Inf, but you could at least compare with it), but starting
with gcc-3.3.1 in 2003, it is always +Inf due to evaluating it at
compile time in the default rounding precision.
expressions on i386 are evaluated in the range of the long double type,
so this is wrong in a different but hopefully less worse way than
before. Since expressions are evaluated in long double registers,
there is no runtime cost to using long double instead of double to
declare intermediate values (except in cases where this avoids compiler
bugs), and by careful use of float_t or double_t it is possible to
avoid some of the compiler bugs in this area, provided these types are
declared as long double.
I was going to change float.h to be less broken and more usable in
combination with the change here (in particular, it is more necessary
to know the effective number of bits in a double_t when double_t !=
double, since DBL_MANT_DIG no longer logically gives this, and
LDBL_MANT_DIG doesn't give it either with FreeBSD-i386's default
rounding precision. However, this was too hard for now. In particular,
LDBL_MANT_DIG is used a lot in libm, so it cannot be changed. One
thing that is completely broken now is LDBL_MAX. This may have sort
of worked when it was changed from DBL_MAX in 2002 (adding 0 to it at
runtime gave +Inf, but you could at least compare with it), but starting
with gcc-3.3.1 in 2003, it is always +Inf due to evaluating it at
compile time in the default rounding precision.
tree structure that encodes the level of cache sharing and other
properties.
- Provide several convenience functions for creating one and two level
cpu trees as well as a default flat topology. The system now always
has some topology.
- On i386 and amd64 create a seperate level in the hierarchy for HTT
and multi-core cpus. This will allow the scheduler to intelligently
load balance non-uniform cores. Presently we don't detect what level
of the cache hierarchy is shared at each level in the topology.
- Add a mechanism for testing common topologies that have more information
than the MD code is able to provide via the kern.smp.topology tunable.
This should be considered a debugging tool only and not a stable api.
Sponsored by: Nokia
of fpget*() and fpset*()).
The i386 fpget*() were efficient but a bit obfuscated (using macros
and a case statement to demultiplex them through a single inline).
The demultiplexing mainly gave smaller source code.
The i386 fpset*() were obfuscated in the same way and were very
inefficient due to the case statement not having enough cases or
complexity so all cases used the FP environment.
This also fixes a harmless bug in rev.1.12. fpsetmask() extracted the
old value from the bit-field twice, but the doubled shift was harmless
since the shift count is 0.
All fp*() interfaces are now inline functions on i386. They used to
be macros that call (a different set of) inline functions. This is a
small ABI change which shouldn't cause problems since cases where
inlining fails (mainly -O0) only give (working) static functions.
others can be replaced cleanly by the amd64 versions. There is no
current amd64 version to merge, but there is an old one which is
similar.
Fix the following bugs in fpresetsticky():
- garbage args clobbered non-sticky bits in the status register
- the return value was usually garbage since it was masked with the
arg instead of with the field selector.
Optimize fpresetsticky() to avoid using the environment as in
feclearexcept() (use only fnclex() if possible) and also to avoid
using fnclex() for null changes. The second of these optimizations
might not be so good since its branch might cost more than it saves.
pv_list_count from struct md_page. Ever since Peter rewrote the pv
entry allocator for amd64 and i386 pv_list_count has been correctly
maintained but otherwise unused.
