rather than 20. The MP 1.4 specification states in Appendix B.2:
"A period of 20 microseconds should be sufficient for IPI dispatch to
complete under normal operating conditions".
(Note that this appears to be separate from the 10 millisecond (INIT) and
200 microsecond (STARTUP) waits after the IPIs are dispatched.) The
Intel SDM is silent on this issue as far as I can tell.
At least some hardware requires 60 microseconds as noted in the PR, so
bump this to 100 to be on the safe side.
PR: 197756
Reported by: zaphod@berentweb.com
MFC after: 1 week
As is described at http://llvm.org/bugs/show_bug.cgi?id=22408, the GNU
linkers ld.bfd and ld.gold currently only support a subset of the
whole range of AArch64 ELF TLS relocations. Furthermore, they assume
that some of the code sequences to access thread-local variables are
produced in a very specific sequence. When the sequence is not as the
linker expects, it can silently mis-relaxe/mis-optimize the
instructions.
Even if that wouldn't be the case, it's good to produce the exact
sequence, as that ensures that linkers can perform optimizing
relaxations.
This patch:
* implements support for 16MiB TLS area size instead of 4GiB TLS area
size. Ideally clang would grow an -mtls-size option to allow support
for both, but that's not part of this patch.
* by default doesn't produce local dynamic access patterns, as even
modern ld.bfd and ld.gold linkers do not support the associated
relocations. An option (-aarch64-elf-ldtls-generation) is added to
enable generation of local dynamic code sequence, but is off by
default.
* makes sure that the exact expected code sequence for local dynamic
and general dynamic accesses is produced, by making use of a new
pseudo instruction. The patch also removes two
(AArch64ISD::TLSDESC_BLR, AArch64ISD::TLSDESC_CALL) pre-existing
AArch64-specific pseudo SDNode instructions that are superseded by
the new one (TLSDESC_CALLSEQ).
Submitted by: Kristof Beyls
Differential Revision: https://reviews.freebsd.org/D2175
[libcxx] Fix PR22771 - Support access control SFINAE in the library
version of is_convertible.
Summary:
Currently the conversion check does not take place in a context where
access control SFINAE is applied. This patch changes the context of
the test expression so that SFINAE occurs if access control does not
permit the conversion.
Related bug: https://llvm.org/bugs/show_bug.cgi?id=22771
Reviewers: mclow.lists, rsmith, dim
Reviewed By: dim
Subscribers: dim, rodrigc, emaste, cfe-commits
Differential Revision: http://reviews.llvm.org/D8461
This fixes building clang, and other programs using libc++, with newer
versions of gcc (specifically, gcc 4.8 and higher).
Reported by: rodrigc
MFC after: 1 week
ELF toolchain readelf lacked some functionality at the time other tools
(like size, strip, nm, etc.) were switched over to the ELF toolchain
versions. That has been addressed as of the last update, so we can add
it to the list.
PR: 198950 [exp-run]
Reviewed by: bapt, imp, rpaulo
Relnotes: yes
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D2156
ask for resource reclamation again.
This is kind of dirty hack, but as last resort this is better then stuck
indefinitely because of KVA fragmentation, waiting until some random event
free something sufficient. OpenSolaris also has this hack in its vmem(9).
MFC after: 2 weeks
uintptr_t may be 64-bit on some platforms, therefore when
finding xrefinfo by pointer to device the high word is being
cut off due to cast to phandle_t which is 32-bit long by definition.
Due to that we loose the high word of the address to compare with
xi->dev's address.
To fix that, first argument of xrefinfo_find() is extended to
uintptr_t and is being cast to appropriate type (phandle_t)
when compared.
Submitted by: Zbigniew Bodek <zbb@semihalf.com>
Reviewed by: nwhitehorn
Obtained from: Semihalf
* Remove vm_umount_base function which is currently unused.
* Add umount_loop function which loops attempting to unmount one filesystem.
* Replace calls to umount with calls to umount_loop.
* Don't attempt to unmount ${DESTDIR}/dev if it isn't mounted.
The looping is necessary because sometimes umount fails due to filesystems
being busy. The most common cause of such busyness is periodic(8) jobs
running `find / ...`.
Reviewed by: gjb
Handle the VIRQ_DEBUG signal and print a stack trace of each vCPU on the Xen
console. This is only used for debug purposes and is triggered by the
administrator of the Xen host.
Sponsored by: Citrix Systems R&D
MFC after: 1 week
script. This reimplementation is much simpler than dtest.pl and is more
amenable to being run under Kyua - dtest.pl writes error output to a
temporary directory that is deleted when the run finishes, making it hard
to debug test failures. This change also removes the test suite's dependency
on perl.
This adds an upper bound, dtrace_ustackdepth_max, to the number of frames
traversed when computing the userland stack depth. Some programs - notably
firefox - are otherwise able to trigger an infinite loop in
dtrace_getustack_common(), causing a panic.
MFC after: 1 week
This is used by the 'athsurvey' command to print out channel survey
statistics - % busy times transmit, receive and airtime.
It's as buggy and incomplete as the rest of the HAL survey support -
notably, tying into the ANI code to read channel stats and occasionally
getting garbage counters isn't very nice. It also doesn't (yet!) get
channel survey information during a scan. But it's good enough for
basic air-time debugging, which is why I'm committing it in this state.
Tested:
* AR9380, STA mode
rathe than private in each HAL module.
Whilst here, modify ath_hal_private to always have the per-channel
noisefloor stats, rather than conditionally. This just makes
life easier in general (no strange ABI differences between different
HAL compile options.)
Add a couple of methods (clear/reset, add) rather than using
hand-rolled versions of things.
This symptom is "calibrations don't ever run", which may cause some
pretty spectacularly bad behaviour in noisy environments or with longer
uptimes.
Thanks to dtrace to make it easy to check if specific non-inlined functions
are getting called by things like the ANI and calibration HAL methods.
Grr.
Tested:
* AR9380, STA mode
Use list for the cancellation points enumeration. Move notes about
functions into the list inline.
The discussion of the idiomatic use of cancellation facilities does
not belong to RETURN VALUES section, move it to NOTES.
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Note that to cancel blocked kevent(2) call, changelist must be empty,
since we cannot cancel a call which already made changes to the
process state. And in reverse, call which only makes changes to the
kqueue state, without waiting for an event, is not cancellable. This
makes a natural usage model to migrate kqueue loop to support
cancellation, where existing single kevent(2) call must be split into
two: first uncancellable update of kqueue, then cancellable wait for
events.
Note that this is ABI-incompatible change, but it is believed that
there is no cancel-safe code that relies on kevent(2) not being a
cancellation point. Option to preserve the ABI would be to keep
kevent(2) as is, but add new call with flags to specify cancellation
behaviour, which only value seems to add complications.
Suggested and reviewed by: jilles
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks