- Add
nvlist_{add,get,take,move,exists,free}_{number,bool,string,nvlist,
descriptor} functions.
- Add support for (un)packing arrays.
- Add the nvl_array_next field to the nvlist structure.
If an array is added by the nvlist_{move,add}_nvlist_array function
this field will contains next element in the array.
- Add the nitems field to the nvpair and nvpair_header structure.
This field contains number of elements in the array.
- Add special flag (NV_FLAG_IN_ARRAY) which is set if nvlist is a part of
an array.
- Add special type (NV_TYPE_NVLIST_ARRAY_NEXT).This type is used only
on packing/unpacking.
- Add new API for traversing arrays (nvlist_get_array_next).
- Add the nvlist_get_pararr function which combines the
nvlist_get_array_next and nvlist_get_parent functions. If nvlist is in
the array it will return next element from array. If nvlist is last
element in array or it isn't in array it will return his
container (parent). This function should simplify traveling over nvlist.
- Add tests for new features.
- Add documentation for new functions.
- Add my copyright.
- Regenerate the sys/cddl/compat/opensolaris/sys/nvpair.h file.
PR: 191083
Reviewed by: allanjude (doc)
Approved by: pjd (mentor)
operation as a write barrier. That description has never been correct,
and it has caused confusion. An acquire operation orders writes as well
as reads, and a release operation orders reads as well as writes.
Also, explicitly say that a thread doesn't see its own accesses being
reordered. The reordering of a thread's accesses is only (potentially)
visible to another thread. Thus, memory barriers need only be used to
control the ordering of accesses between threads, not within a thread.
Reviewed by: bde, kib
Discussed with: jhb
MFC after: 1 week
with higher quality registers (presumably in a module that has just been
loaded), do not undo the user's choice by switching to the new timecounter.
Document that behavior, and also the fact that there is no way to unregister
a timecounter (and thus no way to unload a module containing one).
eliminating the need to build a custom kernel to use the CTS signal.
The historical UART_PPS_ON_CTS kernel option is still honored, but now it
can be overridden at runtime using a tunable to configure all uart devices
(hw.uart.pps_mode) or specific devices (dev.uart.#.pps_mode). The per-
device config is both a tunable and a writable sysctl.
This syncs the PPS capabilities of uart(4) with the enhancements recently
recently added to ucom(4) for capturing from USB serial devices.
Relnotes: yes
multiple processors. In particular, clearly state that the operations
are always atomic when they are applied to the default memory type
that is used by the kernel (and applications).
Reviewed by: kib, jhb (an earlier version)
MFC after: 1 week
There are still several bugs, but I've been using it for a while now.
Thanks to all the testers and to Adrian for his help with this
driver.
This driver isn't connected to the build yet, but it will be soon.
There's no MFC planned because the driver isn't very stable yet.
Reviewed by: adrian
Obtained from: https://github.com/rpaulo/iwm
Tested by: adrian, gjb, dumbbell (others that I forgot).
Relnotes: yes
CloudABI has two separate kernel modules: cloudabi and cloudabi64. The
first module contains all the pointer size independent code, whereas
cloudabi64 contains the actual 64-bits specific system calls and the ELF
loader.
Reviewed by: wblock
Obtained from: https://github.com/NuxiNL/freebsd
Differential Revision: https://reviews.freebsd.org/D3258
doubt most people will read to the end... Note the use of sys/cdefs.h
for pre-C11 compilers...
I didn't included a note about being compatibile w/ userland since a
C11 feature should be obviously usable in userland...
Suggested by: imp
to no longer claim they are experimental.
Reviewed by: rwatson@, wblock@
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D2985
The random_get() system call works similar to getentropy()/getrandom()
on OpenBSD/Linux. It fills a buffer with random data.
This change introduces a new function, read_random_uio(), that is used
to implement read() on the random devices. We can call into this
function from within the CloudABI compatibility layer.
Approved by: secteam
Reviewed by: jmg, markm, wblock
Obtained from: https://github.com/NuxiNL/freebsd
Differential Revision: https://reviews.freebsd.org/D3053
- Tweek man page.
- Remove all mention of RANDOM_FORTUNA. If the system owner wants YARROW or DUMMY, they ask for it, otherwise they get FORTUNA.
- Tidy up headers a bit.
- Tidy up declarations a bit.
- Make static in a couple of places where needed.
- Move Yarrow/Fortuna SYSINIT/SYSUNINIT to randomdev.c, moving us towards a single file where the algorithm context is used.
- Get rid of random_*_process_buffer() functions. They were only used in one place each, and are better subsumed into those places.
- Remove *_post_read() functions as they are stubs everywhere.
- Assert against buffer size illegalities.
- Clean up some silly code in the randomdev_read() routine.
- Make the harvesting more consistent.
- Make some requested argument name changes.
- Tidy up and clarify a few comments.
- Make some requested comment changes.
- Make some requested macro changes.
* NOTE: the thing calling itself a 'unit test' is not yet a proper
unit test, but it helps me ensure things work. It may be a proper
unit test at some time in the future, but for now please don't make
any assumptions or hold any expectations.
Differential Revision: https://reviews.freebsd.org/D2025
Approved by: so (/dev/random blanket)
This is based on work done by jeff@ and jhb@, as well as the numa.diff
patch that has been circulating when someone asks for first-touch NUMA
on -10 or -11.
* Introduce a simple set of VM policy and iterator types.
* tie the policy types into the vm_phys path for now, mirroring how
the initial first-touch allocation work was enabled.
* add syscalls to control changing thread and process defaults.
* add a global NUMA VM domain policy.
* implement a simple cascade policy order - if a thread policy exists, use it;
if a process policy exists, use it; use the default policy.
* processes inherit policies from their parent processes, threads inherit
policies from their parent threads.
* add a simple tool (numactl) to query and modify default thread/process
policities.
* add documentation for the new syscalls, for numa and for numactl.
* re-enable first touch NUMA again by default, as now policies can be
set in a variety of methods.
This is only relevant for very specific workloads.
This doesn't pretend to be a final NUMA solution.
The previous defaults in -HEAD (with MAXMEMDOM set) can be achieved by
'sysctl vm.default_policy=rr'.
This is only relevant if MAXMEMDOM is set to something other than 1.
Ie, if you're using GENERIC or a modified kernel with non-NUMA, then
this is a glorified no-op for you.
Thank you to Norse Corp for giving me access to rather large
(for FreeBSD!) NUMA machines in order to develop and verify this.
Thank you to Dell for providing me with dual socket sandybridge
and westmere v3 hardware to do NUMA development with.
Thank you to Scott Long at Netflix for providing me with access
to the two-socket, four-domain haswell v3 hardware.
Thank you to Peter Holm for running the stress testing suite
against the NUMA branch during various stages of development!
Tested:
* MIPS (regression testing; non-NUMA)
* i386 (regression testing; non-NUMA GENERIC)
* amd64 (regression testing; non-NUMA GENERIC)
* westmere, 2 socket (thankyou norse!)
* sandy bridge, 2 socket (thankyou dell!)
* ivy bridge, 2 socket (thankyou norse!)
* westmere-EX, 4 socket / 1TB RAM (thankyou norse!)
* haswell, 2 socket (thankyou norse!)
* haswell v3, 2 socket (thankyou dell)
* haswell v3, 2x18 core (thankyou scott long / netflix!)
* Peter Holm ran a stress test suite on this work and found one
issue, but has not been able to verify it (it doesn't look NUMA
related, and he only saw it once over many testing runs.)
* I've tested bhyve instances running in fixed NUMA domains and cpusets;
all seems to work correctly.
Verified:
* intel-pcm - pcm-numa.x and pcm-memory.x, whilst selecting different
NUMA policies for processes under test.
Review:
This was reviewed through phabricator (https://reviews.freebsd.org/D2559)
as well as privately and via emails to freebsd-arch@. The git history
with specific attributes is available at https://github.com/erikarn/freebsd/
in the NUMA branch (https://github.com/erikarn/freebsd/compare/local/adrian_numa_policy).
This has been reviewed by a number of people (stas, rpaulo, kib, ngie,
wblock) but not achieved a clear consensus. My hope is that with further
exposure and testing more functionality can be implemented and evaluated.
Notes:
* The VM doesn't handle unbalanced domains very well, and if you have an overly
unbalanced memory setup whilst under high memory pressure, VM page allocation
may fail leading to a kernel panic. This was a problem in the past, but it's
much more easily triggered now with these tools.
* This work only controls the path through vm_phys; it doesn't yet strongly/predictably
affect contigmalloc, KVA placement, UMA, etc. So, driver placement of memory
isn't really guaranteed in any way. That's next on my plate.
Sponsored by: Norse Corp, Inc.; Dell
OCF w/o documentation...
Document the new (8+ year old) device_t way of handling things, that
_unregister_all will leave no threads in newsession, the _SYNC flag,
the requirement that a flag be specified...
Other minor changes like breaking up a wall of text into paragraphs...
line statements inside of braces is recognized as an acceptable
style.
http://reviews.freebsd.org/V3
As always, this isn't license for wholesale change, etc.
mean what you think it should... This will be fixed in the future
with a flag rename, but document what the flag really does and make
the _IV_ flags clear what their presents (or lack there of) means...
Reviewed by: gnn, eri (both earlier version)
* GENERAL
- Update copyright.
- Make kernel options for RANDOM_YARROW and RANDOM_DUMMY. Set
neither to ON, which means we want Fortuna
- If there is no 'device random' in the kernel, there will be NO
random(4) device in the kernel, and the KERN_ARND sysctl will
return nothing. With RANDOM_DUMMY there will be a random(4) that
always blocks.
- Repair kern.arandom (KERN_ARND sysctl). The old version went
through arc4random(9) and was a bit weird.
- Adjust arc4random stirring a bit - the existing code looks a little
suspect.
- Fix the nasty pre- and post-read overloading by providing explictit
functions to do these tasks.
- Redo read_random(9) so as to duplicate random(4)'s read internals.
This makes it a first-class citizen rather than a hack.
- Move stuff out of locked regions when it does not need to be
there.
- Trim RANDOM_DEBUG printfs. Some are excess to requirement, some
behind boot verbose.
- Use SYSINIT to sequence the startup.
- Fix init/deinit sysctl stuff.
- Make relevant sysctls also tunables.
- Add different harvesting "styles" to allow for different requirements
(direct, queue, fast).
- Add harvesting of FFS atime events. This needs to be checked for
weighing down the FS code.
- Add harvesting of slab allocator events. This needs to be checked for
weighing down the allocator code.
- Fix the random(9) manpage.
- Loadable modules are not present for now. These will be re-engineered
when the dust settles.
- Use macros for locks.
- Fix comments.
* src/share/man/...
- Update the man pages.
* src/etc/...
- The startup/shutdown work is done in D2924.
* src/UPDATING
- Add UPDATING announcement.
* src/sys/dev/random/build.sh
- Add copyright.
- Add libz for unit tests.
* src/sys/dev/random/dummy.c
- Remove; no longer needed. Functionality incorporated into randomdev.*.
* live_entropy_sources.c live_entropy_sources.h
- Remove; content moved.
- move content to randomdev.[ch] and optimise.
* src/sys/dev/random/random_adaptors.c src/sys/dev/random/random_adaptors.h
- Remove; plugability is no longer used. Compile-time algorithm
selection is the way to go.
* src/sys/dev/random/random_harvestq.c src/sys/dev/random/random_harvestq.h
- Add early (re)boot-time randomness caching.
* src/sys/dev/random/randomdev_soft.c src/sys/dev/random/randomdev_soft.h
- Remove; no longer needed.
* src/sys/dev/random/uint128.h
- Provide a fake uint128_t; if a real one ever arrived, we can use
that instead. All that is needed here is N=0, N++, N==0, and some
localised trickery is used to manufacture a 128-bit 0ULLL.
* src/sys/dev/random/unit_test.c src/sys/dev/random/unit_test.h
- Improve unit tests; previously the testing human needed clairvoyance;
now the test will do a basic check of compressibility. Clairvoyant
talent is still a good idea.
- This is still a long way off a proper unit test.
* src/sys/dev/random/fortuna.c src/sys/dev/random/fortuna.h
- Improve messy union to just uint128_t.
- Remove unneeded 'static struct fortuna_start_cache'.
- Tighten up up arithmetic.
- Provide a method to allow eternal junk to be introduced; harden
it against blatant by compress/hashing.
- Assert that locks are held correctly.
- Fix the nasty pre- and post-read overloading by providing explictit
functions to do these tasks.
- Turn into self-sufficient module (no longer requires randomdev_soft.[ch])
* src/sys/dev/random/yarrow.c src/sys/dev/random/yarrow.h
- Improve messy union to just uint128_t.
- Remove unneeded 'staic struct start_cache'.
- Tighten up up arithmetic.
- Provide a method to allow eternal junk to be introduced; harden
it against blatant by compress/hashing.
- Assert that locks are held correctly.
- Fix the nasty pre- and post-read overloading by providing explictit
functions to do these tasks.
- Turn into self-sufficient module (no longer requires randomdev_soft.[ch])
- Fix some magic numbers elsewhere used as FAST and SLOW.
Differential Revision: https://reviews.freebsd.org/D2025
Reviewed by: vsevolod,delphij,rwatson,trasz,jmg
Approved by: so (delphij)
adding macros to define class lists.
This change is backwards compatible for all use within C and C++
programs. Only C++ programs will have added support to use the queue
macros within classes. Previously the queue macros could only be used
within structures.
The queue.3 manual page has been updated to describe the new
functionality and some alphabetic sorting has been done while
at it.
Differential Revision: https://reviews.freebsd.org/D2745
PR: 200827 (exp-run)
MFC after: 2 weeks
release barriers, not read and write barriers. They fence all memory
accesses from the respective side, not limited by the kind of
operation.
Reviewed by: jhb
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Off by default, build behaves normally.
WITH_META_MODE we get auto objdir creation, the ability to
start build from anywhere in the tree.
Still need to add real targets under targets/ to build packages.
Differential Revision: D2796
Reviewed by: brooks imp
MAM is Medium Auxiliary Memory and is most commonly found as flash
chips on tapes.
This includes support for reading attributes and decoding most
known attributes, but does not yet include support for writing
attributes or reporting attributes in XML format.
libsbuf/Makefile:
Add subr_prf.c for the new sbuf_hexdump() function. This
function is essentially the same function.
libsbuf/Symbol.map:
Add a new shared library minor version, and include the
sbuf_hexdump() function.
libsbuf/Version.def:
Add version 1.4 of the libsbuf library.
libutil/hexdump.3:
Document sbuf_hexdump() alongside hexdump(3), since it is
essentially the same function.
camcontrol/Makefile:
Add attrib.c.
camcontrol/attrib.c:
Implementation of READ ATTRIBUTE support for camcontrol(8).
camcontrol/camcontrol.8:
Document the new 'camcontrol attrib' subcommand.
camcontrol/camcontrol.c:
Add the new 'camcontrol attrib' subcommand.
camcontrol/camcontrol.h:
Add a function prototype for scsiattrib().
share/man/man9/sbuf.9:
Document the existence of sbuf_hexdump() and point users to
the hexdump(3) man page for more details.
sys/cam/scsi/scsi_all.c:
Add a table of known attributes, text descriptions and
handler functions.
Add a new scsi_attrib_sbuf() function along with a number
of other related functions that help decode attributes.
scsi_attrib_ascii_sbuf() decodes ASCII format attributes.
scsi_attrib_int_sbuf() decodes binary format attributes, and
will pass them off to scsi_attrib_hexdump_sbuf() if they're
bigger than 8 bytes.
scsi_attrib_vendser_sbuf() decodes the vendor and drive
serial number attribute.
scsi_attrib_volcoh_sbuf() decodes the Volume Coherency
Information attribute that LTFS writes out.
sys/cam/scsi/scsi_all.h:
Add a number of attribute-related structure definitions and
other defines.
Add function prototypes for all of the functions added in
scsi_all.c.
sys/kern/subr_prf.c:
Add a new function, sbuf_hexdump(). This is the same as
the existing hexdump(9) function, except that it puts the
result in an sbuf.
This also changes subr_prf.c so that it can be compiled in
userland for includsion in libsbuf.
We should work to change this so that the kernel hexdump
implementation is a wrapper around sbuf_hexdump() with a
statically allocated sbuf with a drain. That will require
a drain function that goes to the kernel printf() buffer
that can take a non-NUL terminated string as input.
That is because an sbuf isn't NUL-terminated until it is
finished, and we don't want to finish it while we're still
using it.
We should also work to consolidate the userland hexdump and
kernel hexdump implemenatations, which are currently
separate. This would also mean making applications that
currently link in libutil link in libsbuf.
sys/sys/sbuf.h:
Add the prototype for sbuf_hexdump(), and add another copy
of the hexdump flag values if they aren't already defined.
Ideally the flags should be defined in one place but the
implemenation makes it difficult to do properly. (See
above.)
Sponsored by: Spectra Logic Corporation
MFC after: 1 week
up to 2 rx/tx queues for the 82574.
Program the 82574 to enable 5 msix vectors, assign 1 to each rx queue,
1 to each tx queue and 1 to the link handler.
Inspired by DragonFlyBSD, enable some RSS logic for handling tx queue
handling/processing.
Move multiqueue handler functions so that they line up better in a diff
review to if_igb.c
Always enqueue tx work to be done in em_mq_start, if unable to acquire
the TX lock, then this will be processed in the background later by the
taskqueue. Remove mbuf argument from em_start_mq_locked() as the work
is always enqueued. (stolen from igb)
Setup TARC, TXDCTL and RXDCTL registers for better performance and stability
in multiqueue and singlequeue implementations. Handle Intel errata 3 and
generic multiqueue behavior with the initialization of TARC(0) and TARC(1)
Bind interrupt threads to cpus in order. (stolen from igb)
Add 2 new DDB functions, one to display the queue(s) and their settings and
one to reset the adapter. Primarily used for debugging.
In the multiqueue configuration, bump RXD and TXD ring size to max for the
adapter (4096). Setup an RDTR of 64 and an RADV of 128 in multiqueue configuration
to cut down on the number of interrupts. RADV was arbitrarily set to 2x RDTR
and can be adjusted as needed.
Cleanup the display in top a bit to make it clearer where the taskqueue threads
are running and what they should be doing.
Ensure that both queues are processed by em_local_timer() by writing them both
to the IMS register to generate soft interrupts.
Ensure that an soft interrupt is generated when em_msix_link() is run so that
any races between assertion of the link/status interrupt and a rx/tx interrupt
are handled.
Document existing tuneables: hw.em.eee_setting, hw.em.msix, hw.em.smart_pwr_down, hw.em.sbp
Document use of hw.em.num_queues and the new kernel option EM_MULTIQUEUE
Thanks to Intel for their continued support of FreeBSD.
Reviewed by: erj jfv hiren gnn wblock
Obtained from: Intel Corporation
MFC after: 2 weeks
Relnotes: Yes
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D1994
Leaf drivers should not import the PCI bus interface to add IOV handling.
Instead, move the IOV client methods to a separate kobj interface.
Differential Revision: https://reviews.freebsd.org/D2584
Reviewed by: rstone
Support 7xxx adapters including firmware-assisted TSO and VLAN tagging:
- Solarflare Flareon Ultra 7000 series 10/40G adapters:
- Solarflare SFN7042Q QSFP+ Server Adapter
- Solarflare SFN7142Q QSFP+ Server Adapter
- Solarflare Flareon Ultra 7000 series 10G adapters:
- Solarflare SFN7022F SFP+ Server Adapter
- Solarflare SFN7122F SFP+ Server Adapter
- Solarflare SFN7322F Precision Time Synchronization Server Adapter
- Solarflare Flareon 7000 series 10G adapters:
- Solarflare SFN7002F SFP+ Server Adapter
Support utilities to configure adapters and update firmware.
The work is done by Solarflare developers
(Andy Moreton, Andrew Lee and many others),
Artem V. Andreev <Artem.Andreev at oktetlabs.ru> and me.
Sponsored by: Solarflare Communications, Inc.
MFC after: 2 weeks
Causually read by: gnn
Differential Revision: https://reviews.freebsd.org/D2618
r283105 misspelled kern_psignal as kernel_psignal in one occurrence, and
added trailing whitespace.
While here, change 'call' to the more standard 'function', and say why
the name was changed (taken from the commit message for r225617).
interacts with interrupts, query ACPI and use MWAIT for entrance into
Cx sleep states. Support C1 "I/O then halt" mode. See Intel'
document 302223-007 "Intelб╝ Processor Vendor-Specific ACPI Interface
Specification" for description.
Move the acpi_cpu_c1() function into x86/cpu_machdep.c and use
it instead of inlining "sti; hlt" sequence in several places.
In the acpi(4) man page, besides documenting the dev.cpu.N.cx_methods
sysctl, correct the names for dev.cpu.N.{cx_usage,cx_lowest,cx_supported}
sysctls.
Both jkim and avg have some other patches implementing the mwait
functionality; this work is unrelated. Linux does not rely on the
ACPI to provide correct tables describing Cx modes. Instead, the
driver has pre-defined knowledge of the CPU models, it was supplied by
Intel.
Tested by: pho (previous versions)
Sponsored by: The FreeBSD Foundation
remains. Xen is planning to phase out support for PV upstream since it
is harder to maintain and has more overhead. Modern x86 CPUs include
virtualization extensions that support HVM guests instead of PV guests.
In addition, the PV code was i386 only and not as well maintained recently
as the HVM code.
- Remove the i386-only NATIVE option that was used to disable certain
components for PV kernels. These components are now standard as they
are on amd64.
- Remove !XENHVM bits from PV drivers.
- Remove various shims required for XEN (e.g. PT_UPDATES_FLUSH, LOAD_CR3,
etc.)
- Remove duplicate copy of <xen/features.h>.
- Remove unused, i386-only xenstored.h.
Differential Revision: https://reviews.freebsd.org/D2362
Reviewed by: royger
Tested by: royger (i386/amd64 HVM domU and amd64 PVH dom0)
Relnotes: yes
It is truer to the semantics of logging for messages to *always*
go to the message buffer, where they can eventually be collected
and, in fact, be put into a log file.
This restores the behavior prior to r70239, which seems to have
changed it inadvertently.
Submitted by: Eric Badger <eric@badgerio.us>
Reviewed by: jhb
Approved by: kib (mentor)
Obtained from: Dell Inc.
MFC after: 1 week
waitid() function is required to be cancellable by the standard. The
wait6() and ppoll() follow the other syscalls in their groups.
Reviewed by: jhb, jilles (previous versions)
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
The format of these pages is somewhat experimental, so they may be subject
to further tweaking.
Differential Revision: https://reviews.freebsd.org/D2170
Reviewed by: bcr, rpaulo
MFC after: 2 weeks
Add examples demonstrating how one can list available providers and the
DTrace probes provided by a provider.
Differential Revision: https://reviews.freebsd.org/D2166
Reviewed by: rpaulo
MFC after: 2 weeks
It actually doesn't - "device ctl" automatically pulls in ICL, which
would normally be a part of iscsi.ko. However, doing it that way makes
iscsi.ko unloadable, and building ctl.ko without iscsi.ko (using
MODULES_OVERRIDE) results in ctl.ko that is unloadable, due to missing
symbols that would be resolved to iscsi.ko. And since the symbols
are named "icl_whatever", it's not obvious that it's iscsi.ko that's
required.
If there is a better way - let me know.
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
where we want to create a new IP datagram.
o Add support for RFC6864, which allows to set IP ID for atomic IP
datagrams to any value, to improve performance. The behaviour is
controlled by net.inet.ip.rfc6864 sysctl knob, which is enabled by
default.
o In case if we generate IP ID, use counter(9) to improve performance.
o Gather all code related to IP ID into ip_id.c.
Differential Revision: https://reviews.freebsd.org/D2177
Reviewed by: adrian, cy, rpaulo
Tested by: Emeric POUPON <emeric.poupon stormshield.eu>
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
Relnotes: yes
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
In particular, this allows an administrator to specify "-h" for human
readable output if that is preferred.
The default setting passes "-d", so that can be excluded by using a custom
setting.
Differential Revision: https://reviews.freebsd.org/D2034
Submitted by: Lystopad Aleksandr <laa@laa.zp.ua>
(patch to add option for -h)
Reviewed by: bz
MFC after: 1 week
Many thanks to ian who gently provided me the DS1307 breakout board.
Tested on: Raspberry pi
Differential Revision: https://reviews.freebsd.org/D2022
Reviewed by: rpaulo