Commit graph

1375 commits

Author SHA1 Message Date
Jung-uk Kim
780f139b5b Detect Advanced Power Management Information for AMD CPUs. 2008-10-21 00:17:55 +00:00
John Baldwin
3d074cf37b Bump MAXCPU to 32 now that 32 CPU x86 systems exist.
Tested by:	rwatson, mdtansca
Approved by:	peter
2008-10-01 21:59:04 +00:00
Marius Strobl
6f04e7b9aa Remove ipi_all() and ipi_self() as the former hasn't been used at
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
2008-09-28 18:34:14 +00:00
Joseph Koshy
d0d0192f83 Correct a callchain capture bug on the i386.
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>
2008-09-15 06:47:52 +00:00
Konstantin Belousov
3bd5e467b2 The pcb_gs32p should be per-cpu, not per-thread pointer. This is
location in GDT where the segment descriptor from pcb_gs32sd is
copied, and the location is in GDT local to CPU.

Noted and reviewed by:	peter
MFC after:	1 week
2008-09-08 09:59:05 +00:00
Konstantin Belousov
575a30d883 Fix inconsistencies in the comments.
MFC after:	1 week
2008-09-08 08:58:29 +00:00
John Baldwin
d320e05ca5 Extend the support for PCI-e memory mapped configuration space access:
- 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
2008-08-22 02:14:23 +00:00
John Baldwin
70d12a18f2 Export 'struct pcpu' to userland w/o requiring _KERNEL. A few ports
already define _KERNEL to get to this and I'm about to add hooks to
libkvm to access per-CPU data.

MFC after:	1 week
2008-08-19 19:53:52 +00:00
Stanislav Sedov
e085f869d5 - Add cpuctl(4) pseudo-device driver to provide access to some low-level
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
2008-08-08 16:26:53 +00:00
Alan Cox
494c177e81 Make pmap_kenter_attr() static. 2008-08-04 08:04:09 +00:00
Alan Cox
67cbc11594 Enhance pmap_change_attr() with the ability to demote 1GB page mappings. 2008-08-01 04:55:38 +00:00
Alan Cox
ba65f767c0 Enhance pmap_change_attr(). Specifically, avoid 2MB page demotions, cache
mode changes, and cache and TLB invalidation when some or all of the
specified range is already mapped with the specified cache mode.

Submitted by:	Magesh Dhasayyan
2008-07-31 22:45:28 +00:00
Konstantin Belousov
8f4a1f3a83 Bring back the save/restore of the %ds, %es, %fs and %gs registers for
the 32bit images on amd64.

Change the semantic of the PCB_32BIT pcb flag to request the context
switch code to operate on the segment registers. Its previous meaning
of saving or restoring the %gs base offset is assigned to the new
PCB_GS32BIT flag.

FreeBSD 32bit image activator sets the PCB_32BIT flag, while Linux 32bit
emulation sets PCB_32BIT | PCB_GS32BIT.

Reviewed by:	peter
MFC after:	2 weeks
2008-07-30 11:30:55 +00:00
Alan Cox
9a8f043722 Increase the ceiling on the size of the buffer map. 2008-07-19 23:42:38 +00:00
Alan Cox
8136b7265f Eliminate pmap_growkernel()'s dependence on create_pagetables() preallocating
page directory pages from VM_MIN_KERNEL_ADDRESS through the end of the
kernel's bss.  Specifically, the dependence was in pmap_growkernel()'s one-
time initialization of kernel_vm_end, not in its main body.  (I could not,
however, resist the urge to optimize the main body.)

Reduce the number of preallocated page directory pages to just those needed
to support NKPT page table pages.  (In fact, this allows me to revert a
couple of my earlier changes to create_pagetables().)
2008-07-08 22:59:17 +00:00
Alan Cox
4a7c66163b Change create_pagetables() and pmap_init() so that many fewer page table
pages have to be preallocated by create_pagetables().
2008-07-06 22:36:28 +00:00
Alan Cox
13e0058451 Increase the kernel map's size to 7GB, making room for a kmem map of size
greater than 4GB.  (Auto-sizing will set the ceiling on the kmem map size
to 4.2GB.)
2008-07-05 20:44:55 +00:00
Alan Cox
db0a9105b1 Increase the ceiling on the kmem map's size to 3.6GB. Also, define the
ceiling as a fraction of the kernel map's size rather than an absolute
quantity.  Thus, scaling of the kmem map's size will be automatic with
changes to the kernel map's size.
2008-07-03 04:53:14 +00:00
Alan Cox
17e2138882 Document the layout of the address space, borrowing heavily from
http://lists.freebsd.org/pipermail/freebsd-amd64/2005-July/005578.html
2008-06-30 03:14:39 +00:00
Alan Cox
67ce249ac9 Compute NKPDPE from NKPT. This reduces the number of knobs that must be
turned in order to change the size of the kernel virtual address space.
2008-06-30 02:35:55 +00:00
Alan Cox
ce3cb38836 Strictly speaking, the definition of VM_MAX_KERNEL_ADDRESS is wrong. However,
in practice, the error (currently) makes no difference because the computation
performed by KVADDR() hides the error.  This revision fixes the error.

Also, eliminate a (now) unused definition.
2008-06-29 19:13:27 +00:00
Alan Cox
f4f491d095 Increase the size of the kernel virtual address space to 6GB. Until the
maximum size of the kmem map can be greater than 4GB, there is little point
in making the kernel virtual address space larger than 6GB.

Tested by:	kris@
2008-06-29 18:35:00 +00:00
Ed Schouten
721351876c Remove the unused major/minor numbers from iodev and memdev.
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)
2008-06-25 07:45:31 +00:00
Alan Cox
bd4328d3a6 Ensure that KERNBASE is no less than the virtual address -2GB. 2008-06-23 15:22:53 +00:00
Alan Cox
293ab7c941 Make preparations for increasing the size of the kernel virtual
address space on the amd64 architecture.  The amd64 architecture
requires kernel code and global variables to reside in the highest 2GB
of the 64-bit virtual address space.  Thus, KERNBASE cannot change.
However, KERNBASE is sometimes used as the start of the kernel virtual
address space.  Henceforth, VM_MIN_KERNEL_ADDRESS should be used
instead.  Since KERNBASE and VM_MIN_KERNEL_ADDRESS are still the same
address, there should be no visible effect from this change (yet).
2008-06-20 05:22:09 +00:00
Jeff Roberson
6c47aaae12 - Add an integer argument to idle to indicate how likely we are to wake
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
2008-04-25 05:18:50 +00:00
Poul-Henning Kamp
9b4a8ab7ba Now that all platforms use genclock, shuffle things around slightly
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.
2008-04-22 19:38:30 +00:00
Jeff Roberson
66247efa5a - Add inlines for the monitor and mwait instructions.
Sponsored by:	Nokia
2008-04-18 05:47:56 +00:00
Warner Losh
917ac33d4e This file is unused on amd64. 2008-04-15 02:10:14 +00:00
Poul-Henning Kamp
36bff1ebfb Convert amd64 and i386 to share the atrtc device driver. 2008-04-14 08:00:00 +00:00
John Birrell
e483943791 When building a kernel module, define MAXCPU the same as SMP so
that modules work with and without SMP.
2008-03-27 05:03:26 +00:00
Poul-Henning Kamp
e465985885 The "free-lance" timer in the i8254 is only used for the speaker
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].
2008-03-26 20:09:21 +00:00
Poul-Henning Kamp
ebfbcd612a Rename timer0_max_count to i8254_max_count.
Rename timer0_real_max_count to i8254_real_max_count and make it static.
Rename timer_freq to i8254_freq and make it a loader tunable.
2008-03-26 15:03:24 +00:00
Poul-Henning Kamp
f168bfa529 The RTC related pscnt and psdiv variables have no business being public. 2008-03-26 13:25:27 +00:00
Peter Wemm
6c73bb3557 Move pcb_flags to make trivially better use of cache lines. 2008-03-23 22:45:51 +00:00
Pawel Jakub Dawidek
6eb4157ffc Implement atomic_fetchadd_long() for all architectures and document it.
Reviewed by:	attilio, jhb, jeff, kris (as a part of the uidinfo_waitfree.patch)
2008-03-16 21:20:50 +00:00
John Baldwin
eaf86d1678 Add preliminary support for binding interrupts to CPUs:
- 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}
2008-03-14 19:41:48 +00:00
John Baldwin
5217af301c Rework how the nexus(4) device works on x86 to better handle the idea of
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@
2008-03-13 20:39:04 +00:00
John Baldwin
391664b110 The variable MTRR registers actually have variable-sized PhysBase and
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
2008-03-12 22:09:19 +00:00
John Baldwin
336d8e5536 Add constants for the various fields in MTRR registers.
MFC after:	1 week
Verified by:	md5(1)
2008-03-11 20:10:37 +00:00
Alan Cox
0116b8b321 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.  (Expect this to change.)

Reviewed by:	ups
Tested by:	kris, Peter Holm
2008-03-04 18:50:15 +00:00
Jeff Roberson
81aa71755b - Remove the old smp cpu topology specification with a new, more flexible
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
2008-03-02 07:58:42 +00:00
David Schultz
2cb2359632 Add a few more CPUID feature bits while here. We don't support these
features yet.
2008-02-02 23:17:27 +00:00
David Schultz
67f6aa5ccf SSE4 CPUID bits 2008-02-02 22:40:17 +00:00
Alexander Motin
2a57ca33c7 Move GET_STACK_USAGE from MI header to i386/amd64 MD ones.
Somebody who can, please feel free to implement it for other archs
or copy this one if it suits.
2008-01-31 08:24:27 +00:00
Bruce Evans
a4b679d859 Translate from the i386. All FP constants and operations are evaluated
in the range and precision of their type(s) on amd64, but FLT_EVAL_METHOD
said that they were evalated in the "interesting" (buggy) i387 methods.
float_t was broken compatibly with FLT_EVAL_METHOD.

These definitions seem to be broken on powerpc and possibly on arm.
float_t is float on powerpc with gcc [-notraditional] according to
glibc, and FLT_EVAL_METHOD is marked with XXX on arm.
2008-01-17 13:12:46 +00:00
Bruce Evans
31e30d75d5 Fix fpset*() to not trap if there is a currently unmasked exception.
Unmasked exceptions (which can be fixed up using fpset*() before they
trap) are very rare, especially on amd64 since SSE exceptions trap
synchronously, but I want to merge the faster amd64 implementations of
fpset*() back to i386 without introducing the bug on i386.

The i386 implementation has always avoided the trap automatically by
changing things using load/store of the FP environment, but this is
very slow.  Most changes only affect the control word, so they can
usually be done much more efficiently, and amd64 has always done this,
but loading the control word can trap.

This version use the fast method only in the usual case where it will
not trap.  This only costs a couple of integer instructions (including
one branch which I haven't optimized carefully yet) in the usual case,
but bloats the inlines a lot.  The inlines were already a bit too large
to handle both the FPU and SSE.
2008-01-11 17:11:32 +00:00
Bruce Evans
548868b38d Fix some style bugs:
- fix a previous style fix: shifts should be in the correct direction even
  if they are null.
- restore a comment about namespace pollution from floatingpoint.h 1.12 and
  update it.
- remove unused namespace pollution FP_*REG.
- improve some comments.
- sort macro definitions for entry points.
- don't use underscores for macro args.
2008-01-11 14:11:46 +00:00
Bruce Evans
0714d1a223 Simplify the ifdefs:
- fix this to compile with C++ by casting ints to enums in a few places
  and by using the correct parameter type for _fpsetprec().  Remove
  __cplusplus ifdefs which disabled the buggy code.
- remove __CC_SUPPORTS___INLINE ifdefs.  `__inline' vs `inline', and either
  of these #defined away, are supposed to be handled by very old ifdefs
  in <sys/cdefs.h>.  Thus the __CC_SUPPORTS___INLINE macro is not needed
  here (or anywhere else that it used).  It is less needed here than in
  most places, since this file is userland-only and userland is far from
  supporting INTEL_COMPILER.  The __CC_SUPPORTS___INLINE__ macro which
  was used here is even less needed.  It is to support spelling `inline'
  as `__inline__' instead of the usual spelling `__inline'.

Fix some style bugs that I missed in the previous commit (remove unused
asms and sort more variables).
2008-01-09 15:03:03 +00:00
Bruce Evans
a2de358449 Fix some style bugs (mainly, use explicit shifts when accessing bit-fields
even if the shift count happens to be 0, sort declarations, and spell
__inline normally).
2008-01-09 13:35:31 +00:00
Bruce Evans
fe26672a8f Improve some comments. 2008-01-09 10:42:47 +00:00
Alan Cox
5cccf58676 Shrink the size of struct vm_page on amd64 and i386 by eliminating
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.
2008-01-06 18:51:04 +00:00
Alan Cox
b8e7fc24fe Add configuration knobs for the superpage reservation system. Initially,
the reservation will only be enabled on amd64.
2007-12-27 16:45:39 +00:00
Alan Cox
4ad863249b Recognize architectural support for 1GB virtual pages.
MFC after: 6 weeks
2007-12-08 21:13:01 +00:00
Joseph Koshy
d07f36b075 Kernel and hwpmc(4) support for callchain capture.
Sponsored by:	FreeBSD Foundation and Google Inc.
2007-12-07 08:20:17 +00:00
Robert Watson
3c90d1ea74 Break out stack(9) from ddb(4):
- Introduce per-architecture stack_machdep.c to hold stack_save(9).
- Introduce per-architecture machine/stack.h to capture any common
  definitions required between db_trace.c and stack_machdep.c.
- Add new kernel option "options STACK"; we will build in stack(9) if it is
  defined, or also if "options DDB" is defined to provide compatibility
  with existing users of stack(9).

Add new stack_save_td(9) function, which allows the capture of a stacktrace
of another thread rather than the current thread, which the existing
stack_save(9) was limited to.  It requires that the thread be neither
swapped out nor running, which is the responsibility of the consumer to
enforce.

Update stack(9) man page.

Build tested:	amd64, arm, i386, ia64, powerpc, sparc64, sun4v
Runtime tested:	amd64 (rwatson), arm (cognet), i386 (rwatson)
2007-12-02 20:40:35 +00:00
John Baldwin
98bbce55fa Adjust the code to probe for the PCI config mechanism to use.
- On amd64, just assume type #1 is always used.  PCI 2.0 mandated
  deprecated type #2 and required type #1 for all future bridges which
  was well before amd64 existed.
- For i386, ignore whatever value was in 0xcf8 before testing for type #1
  and instead rely on the other tests to determine if type #1 works.  Some
  newer machines leave garbage in 0xcf8 during boot and as a result the
  kernel doesn't find PCI at all (which greatly confuses ACPI which expects
  PCI to exist when PCI busses are in the namespace).

MFC after:	3 days
Discussed with:	scottl
2007-11-28 22:20:08 +00:00
John Baldwin
8518d50a63 - Add constants for the different memory types in the SMAP table.
- Use the SMAP types and constants from <machine/pc/bios.h> in the boot
  code rather than duplicating it.
2007-10-28 21:23:49 +00:00
Peter Wemm
d556638404 Split /dev/nvram driver out of isa/clock.c for i386 and amd64. I have not
refactored it to be a generic device.
Instead of being part of the standard kernel, there is now a 'nvram' device
for i386/amd64.  It is in DEFAULTS like io and mem, and can be turned off
with 'nodevice nvram'.  This matches the previous behavior when it was
first committed.
2007-10-26 03:23:54 +00:00
Marius Strobl
55aaf894e8 Make the PCI code aware of PCI domains (aka PCI segments) so we can
support machines having multiple independently numbered PCI domains
and don't support reenumeration without ambiguity amongst the
devices as seen by the OS and represented by PCI location strings.
This includes introducing a function pci_find_dbsf(9) which works
like pci_find_bsf(9) but additionally takes a domain number argument
and limiting pci_find_bsf(9) to only search devices in domain 0 (the
only domain in single-domain systems). Bge(4) and ofw_pcibus(4) are
changed to use pci_find_dbsf(9) instead of pci_find_bsf(9) in order
to no longer report false positives when searching for siblings and
dupe devices in the same domain respectively.
Along with this change the sole host-PCI bridge driver converted to
actually make use of PCI domain support is uninorth(4), the others
continue to use domain 0 only for now and need to be converted as
appropriate later on.
Note that this means that the format of the location strings as used
by pciconf(8) has been changed and that consumers of <sys/pciio.h>
potentially need to be recompiled.

Suggested by:	jhb
Reviewed by:	grehan, jhb, marcel
Approved by:	re (kensmith), jhb (PCI maintainer hat)
2007-09-30 11:05:18 +00:00
Alan Cox
7bfda801a8 Change the management of cached pages (PQ_CACHE) in two fundamental
ways:

(1) Cached pages are no longer kept in the object's resident page
splay tree and memq.  Instead, they are kept in a separate per-object
splay tree of cached pages.  However, access to this new per-object
splay tree is synchronized by the _free_ page queues lock, not to be
confused with the heavily contended page queues lock.  Consequently, a
cached page can be reclaimed by vm_page_alloc(9) without acquiring the
object's lock or the page queues lock.

This solves a problem independently reported by tegge@ and Isilon.
Specifically, they observed the page daemon consuming a great deal of
CPU time because of pages bouncing back and forth between the cache
queue (PQ_CACHE) and the inactive queue (PQ_INACTIVE).  The source of
this problem turned out to be a deadlock avoidance strategy employed
when selecting a cached page to reclaim in vm_page_select_cache().
However, the root cause was really that reclaiming a cached page
required the acquisition of an object lock while the page queues lock
was already held.  Thus, this change addresses the problem at its
root, by eliminating the need to acquire the object's lock.

Moreover, keeping cached pages in the object's primary splay tree and
memq was, in effect, optimizing for the uncommon case.  Cached pages
are reclaimed far, far more often than they are reactivated.  Instead,
this change makes reclamation cheaper, especially in terms of
synchronization overhead, and reactivation more expensive, because
reactivated pages will have to be reentered into the object's primary
splay tree and memq.

(2) Cached pages are now stored alongside free pages in the physical
memory allocator's buddy queues, increasing the likelihood that large
allocations of contiguous physical memory (i.e., superpages) will
succeed.

Finally, as a result of this change long-standing restrictions on when
and where a cached page can be reclaimed and returned by
vm_page_alloc(9) are eliminated.  Specifically, calls to
vm_page_alloc(9) specifying VM_ALLOC_INTERRUPT can now reclaim and
return a formerly cached page.  Consequently, a call to malloc(9)
specifying M_NOWAIT is less likely to fail.

Discussed with: many over the course of the summer, including jeff@,
   Justin Husted @ Isilon, peter@, tegge@
Tested by: an earlier version by kris@
Approved by: re (kensmith)
2007-09-25 06:25:06 +00:00
Attilio Rao
c8790f5d09 Fix some entries in the locks static table of witness.
In particular:
- smp_tlb_mtx is no longer used, so it is axed.
- smp rendezvous lock isn't really a leaf spin-mutex. Its bad placement in
  the table, however, has been the source of a false positive LOR reporting
  with the dt_lock.  However, smp rendezvous lock would have had sched_lock
  there for older lock, so it wasn't still a leaf lock.
- allpmaps is only used in ia32 architecture, so it is inserted in the
  appropriate stub.

Addictionally:
- kse_zombie_lock is no longer present, so its definition is axed out.
- zombie_lock doesn't need to have an exported symbol, so just let's it be
  declared as static.

Tested by: kris
Approved by: jeff (mentor)
Approved by: re
2007-09-20 20:38:43 +00:00
Joseph Koshy
298889efcb Define an END() macro for use in i386 and amd64 assembly code, akin
to the one available on the ia64, sparc64, and sun4v architectures.

Approved by:	re (kensmith)
2007-08-22 04:26:07 +00:00
Dag-Erling Smørgrav
83d18f2283 Add a driver for the on-die digital thermal sensor found on Intel Core
and newer CPUs (including Core 2 and Core / Core 2 based Xeons).  The
driver attaches to each cpu device and creates a sysctl node in that
device's sysctl context (dev.cpu.N.temperature).  When invoked, the
handler binds to the appropriate CPU to ensure a correct reading.

Submitted by:	Rui Paulo <rpaulo@fnop.net>
Sponsored by:	Google Summer of Code 2007
Tested by:	des, marcus, Constantine A. Murenin, Ian FREISLICH
Approved by:	re (kensmith)
MFC after:	3 weeks
2007-08-15 19:26:03 +00:00
Marcel Moolenaar
01bd17cc99 Add kdb_cpu_sync_icache(), intended to synchronize instruction
caches with data caches after writing to memory. This typically
is required to make breakpoints work on ia64 and powerpc. For
those architectures the function is implemented.
2007-06-09 21:55:17 +00:00
Attilio Rao
6759608248 Rework the PCPU_* (MD) interface:
- Rename PCPU_LAZY_INC into PCPU_INC
- Add the PCPU_ADD interface which just does an add on the pcpu member
  given a specific value.

Note that for most architectures PCPU_INC and PCPU_ADD are not safe.
This is a point that needs some discussions/work in the next days.

Reviewed by: alc, bde
Approved by: jeff (mentor)
2007-06-04 21:38:48 +00:00
Alan Cox
5b4a3e940f Add the machine-specific definitions for configuring the new physical
memory allocator.

Set the size of phys_avail[] and dump_avail[] using one of these
definitions.

Approved by:	re
2007-06-03 23:18:29 +00:00
Dag-Erling Smørgrav
753bcb5c34 Add CPUID2_PDCM
Requested by:	jkim
MFC after:	3 days
2007-05-31 11:26:45 +00:00
Alexander Kabaev
d586dea015 Remove extern struct pcpu __pcpu[]; from the header file and
move it the the only file where it appears to be used.
2007-05-19 05:03:59 +00:00
Alexander Kabaev
fa298d5ea8 Include machine/pcb.hto turn extern struct pcb stoppcbs[]; construct
into the valid C.
2007-05-19 05:01:43 +00:00
John Baldwin
2e025791ce Handle CPUs with APIC IDs higher than 32 (at least one IBM server uses
an APIC ID of 38 for its second CPU):
- Add a new MAX_APIC_ID constant for the highest valid APIC ID for modern
  systems.
- Size the various arrays in the MADT, MP Table, and SMP code that are
  indexed by APIC IDs to allow for up to MAX_APIC_ID.
- Explicitly go through and assign logical cpu ids to local APICs before
  starting any of the APs up rather than doing it while starting up the
  APs.  This step is now where we honor MAXCPU.

MFC after:	1 week
2007-05-08 22:01:04 +00:00
John Baldwin
fb610ca1f9 Minor fixes and tweaks to the x86 interrupt code:
- Split the intr_table_lock into an sx lock used for most things, and a
  spin lock to protect intrcnt_index.  Originally I had this as a spin lock
  so interrupt code could use it to lookup sources.  However, we don't
  actually do that because it would add a lot of overhead to interrupts,
  and if we ever do support removing interrupt sources, we can use other
  means to safely do so w/o locking in the interrupt handling code.
- Replace is_enabled (boolean) with is_handlers (a count of handlers) to
  determine if a source is enabled or not.  This allows us to notice when
  a source is no longer in use.  When that happens, we now invoke a new
  PIC method (pic_disable_intr()) to inform the PIC driver that the
  source is no longer in use.  The I/O APIC driver frees the APIC IDT
  vector when this happens.  The MSI driver no longer needs to have a
  hack to clear is_enabled during msi_alloc() and msix_alloc() as a result
  of this change as well.
- Add an apic_disable_vector() to reset an IDT vector back to Xrsvd to
  complement apic_enable_vector() and use it in the I/O APIC and MSI code
  when freeing an IDT vector.
- Add a new nexus hook: nexus_add_irq() to ask the nexus driver to add an
  IRQ to its irq_rman.  The MSI code uses this when it creates new
  interrupt sources to let the nexus know about newly valid IRQs.
  Previously the msi_alloc() and msix_alloc() passed some extra stuff
  back to the nexus methods which then added the IRQs.  This approach is
  a bit cleaner.
- Change the MSI sx lock to a mutex.  If we need to create new sources,
  drop the lock, create the required number of sources, then get the lock
  and try the allocation again.
2007-05-08 21:29:14 +00:00
Alan Cox
04a18977c8 Define every architecture as either VM_PHYSSEG_DENSE or
VM_PHYSSEG_SPARSE depending on whether the physical address space is
densely or sparsely populated with memory.  The effect of this
definition is to determine which of two implementations of
vm_page_array and PHYS_TO_VM_PAGE() is used.  The legacy
implementation is obtained by defining VM_PHYSSEG_DENSE, and a new
implementation that trades off time for space is obtained by defining
VM_PHYSSEG_SPARSE.  For now, all architectures except for ia64 and
sparc64 define VM_PHYSSEG_DENSE.  Defining VM_PHYSSEG_SPARSE on ia64
allows the entirety of my Itanium 2's memory to be used.  Previously,
only the first 1 GB could be used.  Defining VM_PHYSSEG_SPARSE on
sparc64 allows USIIIi-based systems to boot without crashing.

This change is a combination of Nathan Whitehorn's patch and my own
work in perforce.

Discussed with: kmacy, marius, Nathan Whitehorn
PR:		112194
2007-05-05 19:50:28 +00:00
John Baldwin
e706f7f0c7 Revamp the MSI/MSI-X code a bit to achieve two main goals:
- Simplify the amount of work that has be done for each architecture by
  pushing more of the truly MI code down into the PCI bus driver.
- Don't bind MSI-X indicies to IRQs so that we can allow a driver to map
  multiple MSI-X messages into a single IRQ when handling a message
  shortage.

The changes include:
- Add a new pcib_if method: PCIB_MAP_MSI() which is called by the PCI bus
  to calculate the address and data values for a given MSI/MSI-X IRQ.
  The x86 nexus drivers map this into a call to a new 'msi_map()' function
  in msi.c that does the mapping.
- Retire the pcib_if method PCIB_REMAP_MSIX() and remove the 'index'
  parameter from PCIB_ALLOC_MSIX().  MD code no longer has any knowledge
  of the MSI-X index for a given MSI-X IRQ.
- The PCI bus driver now stores more MSI-X state in a child's ivars.
  Specifically, it now stores an array of IRQs (called "message vectors" in
  the code) that have associated address and data values, and a small
  virtual version of the MSI-X table that specifies the message vector
  that a given MSI-X table entry uses.  Sparse mappings are permitted in
  the virtual table.
- The PCI bus driver now configures the MSI and MSI-X address/data
  registers directly via custom bus_setup_intr() and bus_teardown_intr()
  methods.  pci_setup_intr() invokes PCIB_MAP_MSI() to determine the
  address and data values for a given message as needed.  The MD code
  no longer has to call back down into the PCI bus code to set these
  values from the nexus' bus_setup_intr() handler.
- The PCI bus code provides a callout (pci_remap_msi_irq()) that the MD
  code can call to force the PCI bus to re-invoke PCIB_MAP_MSI() to get
  new values of the address and data fields for a given IRQ.  The x86
  MSI code uses this when an MSI IRQ is moved to a different CPU, requiring
  a new value of the 'address' field.
- The x86 MSI psuedo-driver loses a lot of code, and in fact the separate
  MSI/MSI-X pseudo-PICs are collapsed down into a single MSI PIC driver
  since the only remaining diff between the two is a substring in a
  bootverbose printf.
- The PCI bus driver will now restore MSI-X state (including programming
  entries in the MSI-X table) on device resume.
- The interface for pci_remap_msix() has changed.  Instead of accepting
  indices for the allocated vectors, it accepts a mini-virtual table
  (with a new length parameter).  This table is an array of u_ints, where
  each value specifies which allocated message vector to use for the
  corresponding MSI-X message.  A vector of 0 forces a message to not
  have an associated IRQ.  The device may choose to only use some of the
  IRQs assigned, in which case the unused IRQs must be at the "end" and
  will be released back to the system.  This allows a driver to use the
  same remap table for different shortage values.  For example, if a driver
  wants 4 messages, it can use the same remap table (which only uses the
  first two messages) for the cases when it only gets 2 or 3 messages and
  in the latter case the PCI bus will release the 3rd IRQ back to the
  system.

MFC after:	1 month
2007-05-02 17:50:36 +00:00
Stephane E. Potvin
0e5179e441 Add support for specifying a minimal size for vm.kmem_size in the loader via
vm.kmem_size_min. Useful when using ZFS to make sure that vm.kmem size will
be at least 256mb (for example) without forcing a particular value via vm.kmem_size.

Approved by: njl (mentor)
Reviewed by: alc
2007-04-21 01:14:48 +00:00
Jung-uk Kim
9c5b213e51 MFP4: Linux set_thread_area syscall (aka TLS) support for amd64.
Initial version was submitted by Divacky Roman and mostly rewritten by me.

Tested by:	emulation
2007-03-30 00:06:21 +00:00
Jung-uk Kim
2be4e4713a Catch up with ACPI-CA 20070320 import. 2007-03-22 18:16:43 +00:00
John Baldwin
b8783b00f8 Add a new apic0 psuedo-device to claim memory resources for the memory
address ranges used by local and I/O APICs in the system.  Some systems
also reserve these ranges as system resources via either PnPBIOS or
ACPI, so this device currently attaches after acpi0 and legacy0 so that
the system resources are given precedence.
2007-03-20 21:53:31 +00:00
Jung-uk Kim
2498f259d4 - Add macros for newly added CPUID bits in the corresponding header files.
- Use correct capticalization in xTPR as Intel uses in their documents.
- Use proper description instead of vendor code name in comment.
2007-03-20 20:22:45 +00:00
Jung-uk Kim
ab5916a526 Add another CPUID for AMD CPUs and fix style(9) while I am here. 2007-03-12 20:27:21 +00:00
Alan Cox
c640357f04 Push down the implementation of PCPU_LAZY_INC() into the machine-dependent
header file.  Reimplement PCPU_LAZY_INC() on amd64 and i386 making it
atomic with respect to interrupts.

Reviewed by: bde, jhb
2007-03-11 05:54:29 +00:00
John Baldwin
4c5bec1161 Change the x86 interrupt code to use FreeBSD CPU IDs (i.e. PCPU_GET(cpuid))
rather than local APIC IDs to keep track of CPUs which can handle
interrupts.
2007-03-06 17:16:47 +00:00
John Baldwin
aa7a005ee0 Use vm_paddr_t rather than uintptr_t when passing the physical address of
APICs to lapic_init() and ioapic_create().
2007-03-05 20:35:17 +00:00
Paolo Pisati
ef544f6312 o break newbus api: add a new argument of type driver_filter_t to
bus_setup_intr()

o add an int return code to all fast handlers

o retire INTR_FAST/IH_FAST

For more info: http://docs.freebsd.org/cgi/getmsg.cgi?fetch=465712+0+current/freebsd-current

Reviewed by: many
Approved by: re@
2007-02-23 12:19:07 +00:00
Bruce Evans
1300fd67f3 Fixed some style bugs. Routine except:
- don't use __GNUCLIKE___OFFSETOF, since __offsetof() is a standard
  FreeBSD implementaion detail which has nothing to do with GNUC.
2007-02-06 18:04:02 +00:00
Bruce Evans
3764a82377 Simplified PCPU_GET() and PCPU_SET(). We must copy through a temporary
variable to avoid invalid constraints in dead code.  Use an array of
u_char's (inside a struct) instead of a char/short/int/long variable so
that the variable and its accesses can be spelled in the same way in all
cases and code doesn't need to be cloned just to hold the spelling
differences.

Fixed strict-aliasing errors in PCPU_SET() and in the amd64 PCPU_GET().
Cast to (void *) as in rev.1.37 of the i386 version where the errors
were fixed for the i386 PCPU_GET() only.  It would be more correct to
copy to and from the temp. variable using memcpy(), but then an
ifdef tangle would be required to ensure using the builtin memcpy().
We depend on fairly aggressive optimization to put the temp. variable
only in a register despite it being copied using
*(type *)(void *)&anothertype and could depend on this when using
memcpy() too.  This seems to work right even for -O0, but the -O0 case
has not been completely tested.

This change gives identical object code for all object files in LINT
on amd64 (except for one file with a __TIME__ stamp).  For LINT on
i386 it gives unimportant differences in instruction order and padding
in a few object files.  This was only tested for -O.

This change (actually a previous version of it) gives the following
reductions in the number of object files in LINT that fail to compile
with -O2 but without the -fno-strict-aliasing kludge:
- amd64: 29 (down from 211)
- i386: 36 (down from 47)

gcc-3.4.6 actually allows the invalid constraints that result from not
using the temp. variable, at least with -O[1-2], but gcc-3.3.3 crashes
on them and I don't want to depend on compiler bugs.
2007-02-06 16:21:09 +00:00
John Baldwin
c632517124 Change GDB_BUFSZ to be large enough to hold a register dump where each
register takes 16 characters (64-bit register in hex).  In practice this
is a slight bit of overkill as 7 of the 56 registers are only 32-bit, but
having the buffer too small results in remote kgdb trashing kernel memory
when it connects.

PR:		amd64/108673
Submitted by:	Ravi Murty, Nikhil Rao @ Intel
MFC after:	3 days
2007-02-05 21:48:32 +00:00
Bruce Evans
71799af2d5 Cleaned up declaration and initialization of clock_lock. It is only
used by clock code, so don't export it to the world for machdep.c to
initialize.  There is a minor problem initializing it before it is
used, since although clock initialization is split up so that parts
of it can be done early, the first part was never done early enough
to actually work.  Split it up a bit more and do the first part as
late as possible to document the necessary order.  The functions that
implement the split are still bogusly exported.

Cleaned up initialization of the i8254 clock hardware using the new
split.  Actually initialize it early enough, and don't work around it
not being initialized in DELAY() when DELAY() is called early for
initialization of some console drivers.

This unfortunately moves a little more code before the early debugger
breakpoint so that it is harder to debug.  The ordering of console and
related initialization is delicate because we want to do as little as
possible before the breakpoint, but must initialize a console.
2007-01-23 08:01:20 +00:00
John Baldwin
5fe82bca57 Expand the MSI/MSI-X API to address some deficiencies in the MSI-X support.
- First off, device drivers really do need to know if they are allocating
  MSI or MSI-X messages.  MSI requires allocating powerof2() messages for
  example where MSI-X does not.  To address this, split out the MSI-X
  support from pci_msi_count() and pci_alloc_msi() into new driver-visible
  functions pci_msix_count() and pci_alloc_msix().  As a result,
  pci_msi_count() now just returns a count of the max supported MSI
  messages for the device, and pci_alloc_msi() only tries to allocate MSI
  messages.  To get a count of the max supported MSI-X messages, use
  pci_msix_count().  To allocate MSI-X messages, use pci_alloc_msix().
  pci_release_msi() still handles both MSI and MSI-X messages, however.
  As a result of this change, drivers using the existing API will only
  use MSI messages and will no longer try to use MSI-X messages.
- Because MSI-X allows for each message to have its own data and address
  values (and thus does not require all of the messages to have their
  MD vectors allocated as a group), some devices allow for "sparse" use
  of MSI-X message slots.  For example, if a device supports 8 messages
  but the OS is only able to allocate 2 messages, the device may make the
  best use of 2 IRQs if it enables the messages at slots 1 and 4 rather
  than default of using the first N slots (or indicies) at 1 and 2.  To
  support this, add a new pci_remap_msix() function that a driver may call
  after a successful pci_alloc_msix() (but before allocating any of the
  SYS_RES_IRQ resources) to allow the allocated IRQ resources to be
  assigned to different message indices.  For example, from the earlier
  example, after pci_alloc_msix() returned a value of 2, the driver would
  call pci_remap_msix() passing in array of integers { 1, 4 } as the
  new message indices to use.  The rid's for the SYS_RES_IRQ resources
  will always match the message indices.  Thus, after the call to
  pci_remap_msix() the driver would be able to access the first message
  in slot 1 at SYS_RES_IRQ rid 1, and the second message at slot 4 at
  SYS_RES_IRQ rid 4.  Note that the message slots/indices are 1-based
  rather than 0-based so that they will always correspond to the rid
  values (SYS_RES_IRQ rid 0 is reserved for the legacy INTx interrupt).
  To support this API, a new PCIB_REMAP_MSIX() method was added to the
  pcib interface to change the message index for a single IRQ.

Tested by:	scottl
2007-01-22 21:48:44 +00:00
Craig Rodrigues
5a09873361 Revert previous change.
Requested by:	kan
2007-01-18 05:46:32 +00:00
Craig Rodrigues
e76c6d8cd3 Forward declare __pcpu as a pointer type instead of an array type to
eliminate GCC 4.1 error: "array type has incomplete element type".
2007-01-18 02:00:04 +00:00
Warner Losh
fed32d7544 Remove 3rd clause, renumber, ok per email 2007-01-12 07:26:21 +00:00
Jung-uk Kim
5efc6c44ff Add SSSE3 extensions and correct CNXT-ID spelling for Intel processors. 2007-01-09 19:23:22 +00:00
Bruce Evans
f28e1c8f99 Fixed some style bugs (mainly assorted errors in comments, and inconsistent
spelling of `result').
2006-12-29 15:29:49 +00:00
Bruce Evans
6c296ffa81 Fixed some style bugs (whitespace only). 2006-12-29 14:28:23 +00:00
Bruce Evans
7e4277e591 Try harder to garbage-collect the "LOCORE" (really asm) version of
MPLOCKED.  The cleaning in rev.1.25 was supposed to have been undone
by rev.1.26, but 1.26 could never have actually affected asm files
since atomic.h is full of C declarations so including it in asm files
would just give syntax errors.  The asm MPLOCKED is even less needed
than when misplaced definitions of it were first removed, and is now
unused in any asm file in the src tree except in anachronismns in
sys/i386/i386/support.s.
2006-12-29 13:36:26 +00:00
Bruce Evans
276c702d8d Removed gratuitous cosmetic differences with the i386 version. This
mainly involves removing all __CC_SUPPORTS___INLINE__ ifdefs.  These
ifdefs are even less needed for amd64 than for i386, but the i386
atomic.h never had them.  The ifdefs here were just an optimization
of obsolescent compatibility cruft (__inline) for a null set of
compilers.  I think null sets of compilers should only be supported
in cases where this is more than an optimization, doesn't require
extensive ifdefs, and only involves not-so-obsolescent compatibility
cruft (plain inline here).
2006-12-28 08:15:14 +00:00
Bruce Evans
26ab2d1d23 Avoid an instruction in atomic_cmpset_{int_long)() in most cases.
These functions are used a lot for mutexes, so this reduces the text
size of an average kernel by about 0.75%.  This wasn't intended to
be a significant optimization, but it somehow increased the maximum
number of packets per second that can be transmitted by my bge hardware
from 320000 to 460000 (this benchmark is CPU-bound and remarkably
sensitive to changes in the text section).

Details: we would prefer to leave the result of the cmpxchg in %al,
but cannot tell gcc that it is there, so we have to convert it to an
integer register.  We converted  to %al, then to %[re]ax, but the
latter step is usually wasted since gcc usually only wants the condition
code and can recover it from %al just as easily as from %[re]ax.  Let
gcc promote %al in the few cases where this is needed.

Nearby style fixes;
- let gcc manage the load of `res', and don't abuse `res' for a copy of `exp'
- don't echo `res's name in comments
- consistently spell the condition code as 'e' after comparison for equality
- don't hard-code %al anywhere except in constraints
- for the version that doesn't use cmpxchg, there is no requirement to use
  %al anywhere, so don't hard-code it in the constraints either.

Style non-fix:
- for the versions that use cmpxchg, keep using "a" (was %[re]ax, now %al)
  for the main output operand, although this is not required.  The input
  and output operands that use the "a" constraint are now decoupled, and
  this makes things clearer except for the reason that the output register
  is hard-coded.  It is now just a hack to tell gcc that the input "a" has
  been clobbered without increasing the number of operands.
2006-12-27 20:26:00 +00:00
Kip Macy
e5f8d4099d Newer versions of gcc don't support treating structures passed by value
as if they were really passed by reference. Specifically, the dead stores
elimination pass in the GCC 4.1 optimiser breaks the non-compliant behavior
on which FreeBSD relied. This change brings FreeBSD up to date by switching
trap frames to being explicitly passed by reference.

Reviewed by: kan
Tested by: kan
2006-12-17 06:48:40 +00:00
John Baldwin
fde45e231a Sort function prototypes. 2006-12-12 19:24:45 +00:00