Commit Graph

781 Commits

Author SHA1 Message Date
Warner Losh
ef1fcaf0f5 Do not include float interfaces when using libsa.
We don't support float in the boot loaders, so don't include
interfaces for float or double in systems headers. In addition, take
the unusual step of spiking double and float to prevent any more
accidental seepage.
2018-02-23 04:04:25 +00:00
Warner Losh
62bca77843 Move __va_list and related defines to sys/sys/_types.h
__va_list and related defines are identical in all the
ARCH/include/_types.h files. Move them to sys/sys/_types.h

Sponsored by: Netflix
2018-02-12 14:48:20 +00:00
Warner Losh
982e7bdafc We don't support gcc < 4.2.1, so varargs.h now is just #error
always. Unifdef for versions prior to 4.2.1 and remove now-unused
header files.

Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D14323
2018-02-12 14:48:14 +00:00
Warner Losh
33e959abab Use standard pattern for stdargs.h
We don't support older compilers. Most of the code in these files is
for pre-3.0 gcc, which is at least 15 years obsolete. Move to using
phk's sys/_stdargs.h for all these platforms.

Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D14323
2018-02-12 14:48:05 +00:00
Nathan Whitehorn
9a8196ce19 Remove SFBUF_OPTIONAL_DIRECT_MAP and such hacks, replacing them across the
kernel by PHYS_TO_DMAP() as previously present on amd64, arm64, riscv, and
powerpc64. This introduces a new MI macro (PMAP_HAS_DMAP) that can be
evaluated at runtime to determine if the architecture has a direct map;
if it does not (or does) unconditionally and PMAP_HAS_DMAP is either 0 or
1, the compiler can remove the conditional logic.

As part of this, implement PHYS_TO_DMAP() on sparc64 and mips64, which had
similar things but spelled differently. 32-bit MIPS has a partial direct-map
that maps poorly to this concept and is unchanged.

Reviewed by:		kib
Suggestions from:	marius, alc, kib
Runtime tested on:	amd64, powerpc64, powerpc, mips64
2018-01-19 17:46:31 +00:00
Pedro F. Giffuni
e3e70e1e67 sparc64: Update idprom.h.
We only take a small part of the NetBSD file in sys/dev/sun/idprom.h.
Bring some comments and update the license.

Obtained from:	NetBSD (CVS rev 1.3)
2017-12-27 22:01:30 +00:00
Marius Strobl
5eff7c4116 Remove MD atomic_load_{32,64,int,long,ptr}(9) obsolete since the addition
of (conflicting) MI ones in r326971.
2017-12-21 01:27:32 +00:00
Konstantin Belousov
30d4f9e888 Add atomic_load(9) and atomic_store(9) operations.
They provide relaxed-ordered atomic access semantic.  Due to the
FreeBSD memory model, the operations are syntaxical wrappers around
the volatile accesses.  The volatile qualifier is used to ensure that
the access not optimized out and in turn depends on the volatile
semantic as implemented by supported compilers.

The motivation for adding the operation is to help people coming from
other systems or knowing the C11/C++ standards where atomics have
special type and require use of the special access operations.  It is
still the case that FreeBSD requires plain load and stores of aligned
integer types to be atomic.

Suggested by:	jhb
Reviewed by:	alc, jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D13534
2017-12-19 09:59:20 +00:00
Pedro F. Giffuni
796df753f4 SPDX: Consider code from Carnegie-Mellon University.
Interesting cases, most likely from CMU Mach sources.
2017-11-30 15:48:35 +00:00
Pedro F. Giffuni
6ce70ec7f9 sys/sparc64: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
2017-11-27 15:10:39 +00:00
Pedro F. Giffuni
51369649b0 sys: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:43:44 +00:00
Pedro F. Giffuni
df57947f08 spdx: initial adoption of licensing ID tags.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.

Initially, only tag files that use BSD 4-Clause "Original" license.

RelNotes:	yes
Differential Revision:	https://reviews.freebsd.org/D13133
2017-11-18 14:26:50 +00:00
Michal Meloun
904d8c492f Add AT_HWCAP2 ELF auxiliary vector.
- allocate value for new AT_HWCAP2 auxiliary vector on all platforms.
 - expand 'struct sysentvec' by new 'u_long *sv_hwcap2', in exactly
   same way as for AT_HWCAP.

MFC after:	1 month
Reviewed by:	kib
Differential Revision:	https://reviews.freebsd.org/D12699
2017-10-21 12:05:01 +00:00
John Baldwin
c2f37b9245 Add AT_HWCAP and AT_EHDRFLAGS on all platforms.
A new 'u_long *sv_hwcap' field is added to 'struct sysentvec'.  A
process ABI can set this field to point to a value holding a mask of
architecture-specific CPU feature flags.  If an ABI does not wish to
supply AT_HWCAP to processes the field can be left as NULL.

The support code for AT_EHDRFLAGS was already present on all systems,
just the #define was not present.  This is a step towards unifying the
AT_* constants across platforms.

Reviewed by:	kib
MFC after:	1 month
Differential Revision:	https://reviews.freebsd.org/D12290
2017-09-14 14:26:55 +00:00
Jason A. Harmening
eb36b1d0bc Clean up MD pollution of bus_dma.h:
--Remove special-case handling of sparc64 bus_dmamap* functions.
  Replace with a more generic mechanism that allows MD busdma
  implementations to generate inline mapping functions by
  defining WANT_INLINE_DMAMAP in <machine/bus_dma.h>.  This
  is currently useful for sparc64, x86, and arm64, which all
  implement non-load dmamap operations as simple wrappers
  around map objects which may be bus- or device-specific.

--Remove NULL-checked bus_dmamap macros.  Implement the
  equivalent NULL checks in the inlined x86 implementation.
  For non-x86 platforms, these checks are a minor pessimization
  as those platforms do not currently allow NULL maps.  NULL
  maps were originally allowed on arm64, which appears to have
  been the motivation behind adding arm[64]-specific barriers
  to bus_dma.h, but that support was removed in r299463.

--Simplify the internal interface used by the bus_dmamap_load*
  variants and move it to bus_dma_internal.h

--Fix some drivers that directly include sys/bus_dma.h
  despite the recommendations of bus_dma(9)

Reviewed by:	kib (previous revision), marius
Differential Revision:	https://reviews.freebsd.org/D10729
2017-07-01 05:35:29 +00:00
Konstantin Belousov
43f41dd393 Make struct syscall_args visible to userspace compilation environment
from machine/proc.h, consistently on all architectures.

Reviewed by:	jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	3 weeks
X-Differential revision:	https://reviews.freebsd.org/D11080
2017-06-12 20:53:44 +00:00
Ed Maste
366e9e4538 fix sparc64 build by restoring 'register' in pcpu.h
Reported by:	jhb
Sponsored by:	The FreeBSD Foundation
2017-05-17 16:32:24 +00:00
Ed Maste
3e85b721d6 Remove register keyword from sys/ and ANSIfy prototypes
A long long time ago the register keyword told the compiler to store
the corresponding variable in a CPU register, but it is not relevant
for any compiler used in the FreeBSD world today.

ANSIfy related prototypes while here.

Reviewed by:	cem, jhb
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D10193
2017-05-17 00:34:34 +00:00
Gleb Smirnoff
83c9dea1ba - Remove 'struct vmmeter' from 'struct pcpu', leaving only global vmmeter
in place.  To do per-cpu stats, convert all fields that previously were
  maintained in the vmmeters that sit in pcpus to counter(9).
- Since some vmmeter stats may be touched at very early stages of boot,
  before we have set up UMA and we can do counter_u64_alloc(), provide an
  early counter mechanism:
  o Leave one spare uint64_t in struct pcpu, named pc_early_dummy_counter.
  o Point counter(9) fields of vmmeter to pcpu[0].pc_early_dummy_counter,
    so that at early stages of boot, before counters are allocated we already
    point to a counter that can be safely written to.
  o For sparc64 that required a whole dummy pcpu[MAXCPU] array.

Further related changes:
- Don't include vmmeter.h into pcpu.h.
- vm.stats.vm.v_swappgsout and vm.stats.vm.v_swappgsin changed to 64-bit,
  to match kernel representation.
- struct vmmeter hidden under _KERNEL, and only vmstat(1) is an exclusion.

This is based on benno@'s 4-year old patch:
https://lists.freebsd.org/pipermail/freebsd-arch/2013-July/014471.html

Reviewed by:	kib, gallatin, marius, lidl
Differential Revision:	https://reviews.freebsd.org/D10156
2017-04-17 17:34:47 +00:00
Patrick Kelsey
67d955aab4 Corrected misspelled versions of rendezvous.
The MFC will include a compat definition of smp_no_rendevous_barrier()
that calls smp_no_rendezvous_barrier().

Reviewed by:	gnn, kib
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D10313
2017-04-09 02:00:03 +00:00
Bruce Evans
f434f3515b Fix printing of negative offsets (typically from frame pointers) again.
I fixed this in 1997, but the fix was over-engineered and fragile and
was broken in 2003 if not before.  i386 parameters were copied to 8
other arches verbatim, mostly after they stopped working on i386, and
mostly without the large comment saying how the values were chosen on
i386.  powerpc has a non-verbatim copy which just changes the uncritical
parameter and seems to add a sign extension bug to it.

Just treat negative offsets as offsets if they are no more negative than
-db_offset_max (default -64K), and remove all the broken parameters.

-64K is not very negative, but it is enough for frame and stack pointer
offsets since kernel stacks are small.

The over-engineering was mainly to go more negative than -64K for the
negative offset format, without affecting printing for more than a
single address.

Addresses in the top 64K of a (full 32-bit or 64-bit) address space
are now printed less well, but there aren't many interesting ones.
For arches that have many interesting ones very near the top (e.g.,
68k has interrupt vectors there), there would be no good limit for
the negative offset format and -64K is a good as anything.
2017-03-26 18:46:35 +00:00
Warner Losh
fbbd9655e5 Renumber copyright clause 4
Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.

Submitted by:	Jan Schaumann <jschauma@stevens.edu>
Pull Request:	https://github.com/freebsd/freebsd/pull/96
2017-02-28 23:42:47 +00:00
Jason A. Harmening
e2a8d17887 Bring back r313037, with fixes for mips:
Implement get_pcpu() for amd64/sparc64/mips/powerpc, and use it to
replace pcpu_find(curcpu) in MI code.

Reviewed by:	andreast, kan, lidl
Tested by:	lidl(mips, sparc64), andreast(powerpc)
Differential Revision:	https://reviews.freebsd.org/D9587
2017-02-19 02:03:09 +00:00
Konstantin Belousov
9fb10d635e Define the vm_ooffset_t and vm_pindex_t types as machine-independend.
The types are for the byte offset and page index in vm object.  They
are similar to off_t, which is defined as 64bit MI integer.  Using MI
definitions will allow to provide consistent MD values of vm
object-related maximum sizes.

Reviewed by:	alc
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2017-02-04 12:26:38 +00:00
Jason A. Harmening
ad62ba6e96 Revert r313037
The switch to get_pcpu() in MI code seems to cause hangs on MIPS.
Back out until we can get a better idea of what's happening there.

Reported by:	kan, lidl
2017-02-04 06:24:49 +00:00
Jason A. Harmening
65ed483615 Implement get_pcpu() for the remaining architectures and use it to
replace pcpu_find(curcpu) in MI code.
2017-02-01 03:32:49 +00:00
Mateusz Guzik
4cf80fbd79 sparc64: add atomic_fcmpset
Tested on hardware provided by feld.

Reviewed by:	marius
2017-01-10 21:10:20 +00:00
Warner Losh
b2a7ac4802 Fix building on i386 and arm. But 'public domain' headers on the files
with no creative content. Include "lost" changes from git:
o Use /dev/efi instead of /dev/efidev
o Remove redundant NULL checks.

Submitted by: kib@, dim@, zbb@, emaste@
2016-10-13 06:56:23 +00:00
Warner Losh
943ac2b07e Include stubs even on the platforms we don't support so libsysdecode
continues to build.
2016-10-11 22:54:29 +00:00
John Baldwin
cc981af204 Add new bus methods for mapping resources.
Add a pair of bus methods that can be used to "map" resources for direct
CPU access using bus_space(9).  bus_map_resource() creates a mapping and
bus_unmap_resource() releases a previously created mapping.  Mappings are
described by 'struct resource_map' object.  Pointers to these objects can
be passed as the first argument to the bus_space wrapper API used for bus
resources.

Drivers that wish to map all of a resource using default settings
(for example, using uncacheable memory attributes) do not need to change.
However, drivers that wish to use non-default settings can now do so
without jumping through hoops.

First, an RF_UNMAPPED flag is added to request that a resource is not
implicitly mapped with the default settings when it is activated.  This
permits other activation steps (such as enabling I/O or memory decoding
in a device's PCI command register) to be taken without creating a
mapping.  Right now the AGP drivers don't set RF_ACTIVE to avoid using
up a large amount of KVA to map the AGP aperture on 32-bit platforms.
Once RF_UNMAPPED is supported on all platforms that support AGP this
can be changed to using RF_UNMAPPED with RF_ACTIVE instead.

Second, bus_map_resource accepts an optional structure that defines
additional settings for a given mapping.

For example, a driver can now request to map only a subset of a resource
instead of the entire range.  The AGP driver could also use this to only
map the first page of the aperture (IIRC, it calls pmap_mapdev() directly
to map the first page currently).  I will also eventually change the
PCI-PCI bridge driver to request mappings of the subset of the I/O window
resource on its parent side to create mappings for child devices rather
than passing child resources directly up to nexus to be mapped.  This
also permits bridges that do address translation to request suitable
mappings from a resource on the "upper" side of the bus when mapping
resources on the "lower" side of the bus.

Another attribute that can be specified is an alternate memory attribute
for memory-mapped resources.  This can be used to request a
Write-Combining mapping of a PCI BAR in an MI fashion.  (Currently the
drivers that do this call pmap_change_attr() directly for x86 only.)

Note that this commit only adds the MI framework.  Each platform needs
to add support for handling RF_UNMAPPED and thew new
bus_map/unmap_resource methods.  Generally speaking, any drivers that
are calling rman_set_bustag() and rman_set_bushandle() need to be
updated.

Discussed on:	arch
Reviewed by:	cem
Differential Revision:	https://reviews.freebsd.org/D5237
2016-05-20 17:57:47 +00:00
Marius Strobl
61a4e586d4 Since r296250 it is no longer possible for devices to use bus space
addresses exceeding 32 bit, so bump BUS_SPACE_MAXADDR to 64 bit.
The whole situation is sub par, though; prior to r296250 and despite
what their names imply, BUS_SPACE_MAX* were primarily, even almost
exclusively used for bus_dma(9). Now these macros also have a vital
role for bus_space(9). However, it does not necessarily hold that
both bus DMA and space addresses universally have the same limits
per platform.
As for sparc64, 64 bit clearly is beyond what can be addressed via
the various IOMMUs. With this change in place, we now rely on the
parent bus DMA tags of the host-to-foo drivers causing the child
tags to be capped as necessary.

PR:		207998
2016-04-10 22:43:36 +00:00
Konstantin Belousov
90edf67ecf POSIX states that #include <signal.h> shall make both mcontext_t and
ucontext_t available.  Our code even has XXX comment about this.

Add a bit of compliance by moving struct __ucontext definition into
sys/_ucontext.h and including it into signal.h and sys/ucontext.h.

Several machine/ucontext.h headers were changed to use namespace-safe
types (like uint64_t->__uint64_t) to not depend on sys/types.h.
struct __stack_t from sys/signal.h is made always visible in private
namespace to satisfy sys/_ucontext.h requirements.

Apparently mips _types.h pollutes global namespace with f_register_t
type definition.  This commit does not try to fix the issue.

PR:	207079
Reported and tested by:	Ting-Wei Lan <lantw44@gmail.com>
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
2016-02-12 07:38:19 +00:00
John Baldwin
5e766348d2 Add an atomic_fetchadd_64() wrapper on sparc64.
Reviewed by:	marius
2016-01-22 00:29:11 +00:00
Nathan Whitehorn
9f4a7eae43 Make using the #address-cells property on the interrupt parent in device
tree parsing opt-out rather than opt-in. All FDT-based systems as well as
PowerPC systems with real Open Firmware use the CHRP-derived binding that
includes it, which makes SPARC the odd man out here. Making it opt-out
avoids astonishment on new platform bring up.
2016-01-02 19:28:35 +00:00
Marius Strobl
258527a372 Change the - hopefully - last piece of ktr(9) to use PCPU_GET(cpuid)
instead of the MD module ID for KTR_CPU.
2015-12-30 18:57:29 +00:00
Marius Strobl
45005f7907 - (Ab)use udivx for dividing the u_int pc_cpuid when implementing
CPU_ISSET(), CPU_SET etc. in sparc64 asm. This approach has the
  benefit of not clobbering %y, allowing to revert r222827 and
  partially r222828.
- In r222828, CATR() already was changed to use the equivalent of
  PCPU_GET(cpuid) instead of the MD module ID for KTR_CPU, so
  belatedly also catch up with the C side of ktr(9). Originally,
  in r203838 CATR() was moved away from directly reading the
  module ID or equivalent as that became impractical with other
  CPU types than USI/II supported. With r222828 in place, per-CPU
  data generally is set up soon enough, though, that employing
  PCPU things in ktr(9) also for use during early stages works.
- Unfortunately, an exception to the latter is the ktr(9) use
  in pmap_bootstrap(), which actually is run so early that even
  checking for bootverbose being set via the loader doesn't work.
  Consequently, replace the ktr(9) use in pmap_bootstrap() with
  OF_printf(9) and put it under #ifdef DIAGNOSTIC instead.

MFC after:	3 days
2015-12-30 13:49:20 +00:00
Marius Strobl
c9c5763bc7 Adapt CATR() to r283283. 2015-12-30 00:17:37 +00:00
John Baldwin
7f911abe54 Add support to libkvm for reading vmcores from other architectures.
- Add a kvaddr_type to represent kernel virtual addresses instead of
  unsigned long.
- Add a struct kvm_nlist which is a stripped down version of struct nlist
  that uses kvaddr_t for n_value.
- Add a kvm_native() routine that returns true if an open kvm descriptor
  is for a native kernel and memory image.
- Add a kvm_open2() function similar to kvm_openfiles().  It drops the
  unused 'swapfile' argument and adds a new function pointer argument for
  a symbol resolving function.  Native kernels still use _fdnlist() from
  libc to resolve symbols if a resolver function is not supplied, but cross
  kernels require a resolver.
- Add a kvm_nlist2() function similar to kvm_nlist() except that it uses
  struct kvm_nlist instead of struct nlist.
- Add a kvm_read2() function similar to kvm_read() except that it uses
  kvaddr_t instead of unsigned long for the kernel virtual address.
- Add a new kvm_arch switch of routines needed by a vmcore backend.
  Each backend is responsible for implementing kvm_read2() for a given
  vmcore format.
- Use libelf to read headers from ELF kernels and cores (except for
  powerpc cores).
- Add internal helper routines for the common page offset hash table used
  by the minidump backends.
- Port all of the existing kvm backends to implement a kvm_arch switch and
  to be cross-friendly by using private constants instead of ones that
  vary by platform (e.g. PAGE_SIZE).  Static assertions are present when
  a given backend is compiled natively to ensure the private constants
  match the real ones.
- Enable all of the existing vmcore backends on all platforms.  This means
  that libkvm on any platform should be able to perform KVA translation
  and read data from a vmcore of any platform.

Tested on:	amd64, i386, sparc64 (marius)
Differential Revision:	https://reviews.freebsd.org/D3341
2015-11-27 18:58:26 +00:00
Marius Strobl
5101cb4efc Merge from r290547:
Since r289279 bufinit() uses mp_ncpus so adapt to what x86 does and
set this variable already in cpu_mp_setmaxid().
While at it, rename cpu_cpuid_prop() to cpu_portid_prop() as well as
the MD cpuid variable to portid to avoid confusion with the MI use
of "cpuid" and make some variable static/global in order to reduce
stack usage.

PR:		204685
2015-11-21 02:49:33 +00:00
Marius Strobl
7888a51f8d - Unbreak dumpsys(9) on sparc64 after r276772
- While at it, arrange #ifndefs in kern_dump.c more intelligently; it's
  rather confusing to have multiple competing and/or unused functions in
  the kernel.
2015-11-16 23:02:33 +00:00
Marius Strobl
1ed1ef30ee Merge r286374 from x86:
Formally pair store_rel(&smp_started) with load_acq(&smp_started).
Similarly to x86, this change is mostly a NOP due to the kernel
being run in total store order.

MFC after:	1 week
2015-09-13 00:08:04 +00:00
Ed Maste
fc8c856029 Rationalize BSD license on sys/*/include/in_cksum.h
Remove the advertising clause from the Regents of the University of
California's license, per the letter dated July 22, 1999.

Update clause numbering.
2015-08-05 19:05:12 +00:00
Ed Maste
96226a9aa7 Rationalize BSD license on sys/*/include/float.h
Remove the advertising clause from the Regents of the University of
California's license, per the letter dated July 22, 1999.

Update clause numbering.
2015-08-05 17:05:35 +00:00
Jason A. Harmening
713841afb2 Add two new pmap functions:
vm_offset_t pmap_quick_enter_page(vm_page_t m)
void pmap_quick_remove_page(vm_offset_t kva)

These will create and destroy a temporary, CPU-local KVA mapping of a specified page.

Guarantees:
--Will not sleep and will not fail.
--Safe to call under a non-sleepable lock or from an ithread

Restrictions:
--Not guaranteed to be safe to call from an interrupt filter or under a spin mutex on all platforms
--Current implementation does not guarantee more than one page of mapping space across all platforms. MI code should not make nested calls to pmap_quick_enter_page.
--MI code should not perform locking while holding onto a mapping created by pmap_quick_enter_page

The idea is to use this in busdma, for bounce buffer copies as well as virtually-indexed cache maintenance on mips and arm.

NOTE: the non-i386, non-amd64 implementations of these functions still need review and testing.

Reviewed by:	kib
Approved by:	kib (mentor)
Differential Revision:	http://reviews.freebsd.org/D3013
2015-08-04 19:46:13 +00:00
Marius Strobl
7815d3948c o Revert the other functional half of r239864, i. e. the merge of r134227
from x86 to use smp_ipi_mtx spin lock not only for smp_rendezvous_cpus()
  but also for the MD cache invalidation, TLB demapping and remote register
  reading IPIs due to the following reasons:
  - The cross-IPI SMP deadlock x86 otherwise is subject to can't happen on
    sparc64. That's because on sparc64, spin locks don't disable interrupts
    completely but only raise the processor interrupt level to PIL_TICK. This
    means that IPIs still get delivered and direct dispatch IPIs such as the
    cache invalidation etc. IPIs in question are still executed.
  - In smp_rendezvous_cpus(), smp_ipi_mtx is held not only while sending an
    IPI_RENDEZVOUS, but until all CPUs have processed smp_rendezvous_action().
    Consequently, smp_ipi_mtx may be locked for an extended amount of time as
    queued IPIs (as opposed to the direct ones) such as IPI_RENDEZVOUS are
    scheduled via a soft interrupt. Moreover, given that this soft interrupt
    is only delivered at PIL_RENDEZVOUS, processing of smp_rendezvous_action()
    on a target may be interrupted by f. e. a tick interrupt at PIL_TICK, in
    turn leading to the target in question trying to send an IPI by itself
    while IPI_RENDEZVOUS isn't fully handled, yet, and, thus, resulting in a
    deadlock.
o As mentioned in the commit message of r245850, on least some sun4u platforms
  concurrent sending of IPIs by different CPUs is fatal. Therefore, hold the
  reintroduced MD ipi_mtx also while delivering cross-traps via MI helpers,
  i. e. ipi_{all_but_self,cpu,selected}().
o Akin to x86, let the last CPU to process cpu_mp_bootstrap() set smp_started
  instead of the BSP in cpu_mp_unleash(). This ensures that all APs actually
  are started, when smp_started is no longer 0.
o In all MD and MI IPI helpers, check for smp_started == 1 rather than for
  smp_cpus > 1 or nothing at all. This avoids races during boot causing IPIs
  trying to be delivered to APs that in fact aren't up and running, yet.
  While at it, move setting of the cpu_ipi_{selected,single}() pointers to
  the appropriate delivery functions from mp_init() to cpu_mp_start() where
  it's better suited and allows to get rid of the global isjbus variable.
o Given that now concurrent IPI delivery no longer is possible, also nuke
  the delays before completely disabling interrupts again in the CPU-specific
  cross-trap delivery functions, previously giving other CPUs a window for
  sending IPIs on their part. Actually, we now should be able to entirely get
  rid of completely disabling interrupts in these functions. Such a change
  needs more testing, though.
o In {s,}tick_get_timecount_mp(), make the {s,}tick variable static. While not
  necessary for correctness, this avoids page faults when accessing the stack
  of a foreign CPU as {s,}tick now is locked into the TLBs as part of static
  kernel data. Hence, {s,}tick_get_timecount_mp() always execute as fast as
  possible, avoiding jitter.

PR:		201245
MFC after:	3 days
2015-07-24 15:13:21 +00:00
Konstantin Belousov
8954a9a4e6 Add the atomic_thread_fence() family of functions with intent to
provide a semantic defined by the C11 fences with corresponding
memory_order.

atomic_thread_fence_acq() gives r | r, w, where r and w are read and
write accesses, and | denotes the fence itself.

atomic_thread_fence_rel() is r, w | w.

atomic_thread_fence_acq_rel() is the combination of the acquire and
release in single operation.  Note that reads after the acq+rel fence
could be made visible before writes preceeding the fence.

atomic_thread_fence_seq_cst() orders all accesses before/after the
fence, and the fence itself is globally ordered against other
sequentially consistent atomic operations.

Reviewed by:	alc
Discussed with:	bde
Sponsored by:	The FreeBSD Foundation
MFC after:	3 weeks
2015-07-08 18:12:24 +00:00
Alan Cox
966272ca33 Retire VM_FREEPOOL_CACHE as the next step in eliminating PG_CACHE pages.
Differential Revision:	https://reviews.freebsd.org/D2712
Reviewed by:	kib
Sponsored by:	EMC / Isilon Storage Division
2015-06-08 04:59:32 +00:00
John Baldwin
dbee5c671a Move the 32-bit compatible procfs types from freebsd32.h to <sys/procfs.h>
and export them to userland.
- Define __HAVE_REG32 on platforms that define a reg32 structure and check
  for this in <sys/procfs.h> to control when to export prstatus32, etc.
- Add prstatus32_t and prpsinfo32_t typedefs for the 32-bit structures.
  libbfd looks for these types, and having them fixes 'gcore' in gdb of a
  32-bit process on a 64-bit platform.
- Use the structure definitions from <sys/procfs.h> in gcore's elf32 core
  dump code instead of duplicating the definitions.

Differential Revision:	https://reviews.freebsd.org/D2142
Reviewed by:	kib, nathanw (powerpc bits)
MFC after:	1 week
2015-04-08 16:30:45 +00:00
Marius Strobl
aed116911d Unbreak sparc64 after r276630 by calling __sparc_sigtramp_setup signal
trampoline as part of the MD __sys_sigaction again.

Submitted by:	kib (initial versions)
MFC after:	3 days
2015-02-16 22:13:03 +00:00
Mark Johnston
bdb9ab0dd9 Factor out duplicated code from dumpsys() on each architecture into generic
code in sys/kern/kern_dump.c. Most dumpsys() implementations are nearly
identical and simply redefine a number of constants and helper subroutines;
a generic implementation will make it easier to implement features around
kernel core dumps. This change does not alter any minidump code and should
have no functional impact.

PR:		193873
Differential Revision:	https://reviews.freebsd.org/D904
Submitted by:	Conrad Meyer <conrad.meyer@isilon.com>
Reviewed by:	jhibbits (earlier version)
Sponsored by:	EMC / Isilon Storage Division
2015-01-07 01:01:39 +00:00