Commit Graph

248 Commits

Author SHA1 Message Date
Olivier Houchard
7045ac437b Instead of using an incomplete list of platforms that uses 64bits time_t
in 32bits mode, special case amd64, as i386 is the only arch that still
uses 32bits time_t.
2019-01-13 00:19:15 +00:00
Alan Somers
6040822c4e Make timespecadd(3) and friends public
The timespecadd(3) family of macros were imported from NetBSD back in
r35029. However, they were initially guarded by #ifdef _KERNEL. In the
meantime, we have grown at least 28 syscalls that use timespecs in some
way, leading many programs both inside and outside of the base system to
redefine those macros. It's better just to make the definitions public.

Our kernel currently defines two-argument versions of timespecadd and
timespecsub.  NetBSD, OpenBSD, and FreeDesktop.org's libbsd, however, define
three-argument versions.  Solaris also defines a three-argument version, but
only in its kernel.  This revision changes our definition to match the
common three-argument version.

Bump _FreeBSD_version due to the breaking KPI change.

Discussed with:	cem, jilles, ian, bde
Differential Revision:	https://reviews.freebsd.org/D14725
2018-07-30 15:46:40 +00:00
Andrew Turner
2bf9501287 Create a new macro for static DPCPU data.
On arm64 (and possible other architectures) we are unable to use static
DPCPU data in kernel modules. This is because the compiler will generate
PC-relative accesses, however the runtime-linker expects to be able to
relocate these.

In preparation to fix this create two macros depending on if the data is
global or static.

Reviewed by:	bz, emaste, markj
Sponsored by:	ABT Systems Ltd
Differential Revision:	https://reviews.freebsd.org/D16140
2018-07-05 17:13:37 +00:00
Mateusz Guzik
5ec2c93667 tc: bcopy -> memcpy 2018-05-04 22:48:10 +00:00
Brooks Davis
6469bdcdb6 Move most of the contents of opt_compat.h to opt_global.h.
opt_compat.h is mentioned in nearly 180 files. In-progress network
driver compabibility improvements may add over 100 more so this is
closer to "just about everywhere" than "only some files" per the
guidance in sys/conf/options.

Keep COMPAT_LINUX32 in opt_compat.h as it is confined to a subset of
sys/compat/linux/*.c.  A fake _COMPAT_LINUX option ensure opt_compat.h
is created on all architectures.

Move COMPAT_LINUXKPI to opt_dontuse.h as it is only used to control the
set of compiled files.

Reviewed by:	kib, cem, jhb, jtl
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D14941
2018-04-06 17:35:35 +00:00
Konstantin Belousov
6f697994fd Use atomic_load(9) to read ppsinfo sequence numbers.
In this case volatile qualifiers enusre that a compiler does not
optimize the accesses out.

Reviewed by:	alc, jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D13534
2017-12-19 10:05:45 +00:00
Pedro F. Giffuni
64de3fdd58 SPDX: use the Beerware identifier. 2017-11-30 20:33:45 +00:00
Konstantin Belousov
70e3b262d1 The th_bintime, th_microtime and th_nanotime members of the timehand
all cache the last system time (uptime + boottime).  Only the format
differs.  Do not re-calculate the bintime and simply use the value
used to calculate the microtime and nanotime.

Group all the updates under the relevant comment.  Remove obsoleted
XXX part.

Submitted by:	Sebastian Huber <sebastian.huber@embedded-brains.de>
MFC after:	1 week
2017-10-11 11:03:11 +00:00
Eric van Gyzen
8addc72b3e Add missing pieces of r315280
I moved this branch from github to a private server, and pulled from the
wrong one when committing r315280, so I failed to include two recent commits.
Thankfully, they were only cosmetic and were included in the review.
Specifically:

Add documentation, polish comments, and improve style(9).

Tested by:	pho (r315280)
MFC after:	2 weeks
Sponsored by:	Dell EMC
Differential Revision:	https://reviews.freebsd.org/D9791
2017-03-14 22:02:02 +00:00
Eric van Gyzen
9dbdf2a169 When the RTC is adjusted, reevaluate absolute sleep times based on the RTC
POSIX 2008 says this about clock_settime(2):

    If the value of the CLOCK_REALTIME clock is set via clock_settime(),
    the new value of the clock shall be used to determine the time
    of expiration for absolute time services based upon the
    CLOCK_REALTIME clock.  This applies to the time at which armed
    absolute timers expire.  If the absolute time requested at the
    invocation of such a time service is before the new value of
    the clock, the time service shall expire immediately as if the
    clock had reached the requested time normally.

    Setting the value of the CLOCK_REALTIME clock via clock_settime()
    shall have no effect on threads that are blocked waiting for
    a relative time service based upon this clock, including the
    nanosleep() function; nor on the expiration of relative timers
    based upon this clock.  Consequently, these time services shall
    expire when the requested relative interval elapses, independently
    of the new or old value of the clock.

When the real-time clock is adjusted, such as by clock_settime(3),
wake any threads sleeping until an absolute real-clock time.
Such a sleep is indicated by a non-zero td_rtcgen.  The sleep functions
will set that field to zero and return zero to tell the caller
to reevaluate its sleep duration based on the new value of the clock.

At present, this affects the following functions:

    pthread_cond_timedwait(3)
    pthread_mutex_timedlock(3)
    pthread_rwlock_timedrdlock(3)
    pthread_rwlock_timedwrlock(3)
    sem_timedwait(3)
    sem_clockwait_np(3)

I'm working on adding clock_nanosleep(2), which will also be affected.

Reported by:	Sebastian Huber <sebastian.huber@embedded-brains.de>
Reviewed by:	jhb, kib
MFC after:	2 weeks
Relnotes:	yes
Sponsored by:	Dell EMC
Differential Revision:	https://reviews.freebsd.org/D9791
2017-03-14 19:06:44 +00:00
Ed Schouten
fd0f59709d Add labels to sysctls related to clocks.
Sysctls like kern.eventtimer.et.*.quality currently embed the name of
the clock device. This is problematic for the Prometheus metrics
exporter for two reasons:

- Some of those clocks have dashes in their names, which Prometheus
  doesn't allow to be used in metric names.
- It doesn't allow for extracting the same property of all clocks on the
  system from within a single query.

Attach these nodes to have a label, so that the Prometheus metrics
exporter gives these metric a uniform name with the name of the clock
attached as a label.

Reviewed by:	cem
Differential Revision:	https://reviews.freebsd.org/D8775
2016-12-14 12:56:58 +00:00
Konstantin Belousov
1680854946 Implement userspace gettimeofday(2) with HPET timecounter.
Right now, userspace (fast) gettimeofday(2) on x86 only works for
RDTSC.  For older machines, like Core2, where RDTSC is not C2/C3
invariant, and which fall to HPET hardware, this means that the call
has both the penalty of the syscall and of the uncached hw behind the
QPI or PCIe connection to the sought bridge.  Nothing can me done
against the access latency, but the syscall overhead can be removed.
System already provides mappable /dev/hpetX devices, which gives
straight access to the HPET registers page.

Add yet another algorithm to the x86 'vdso' timehands. Libc is updated
to handle both RDTSC and HPET.  For HPET, the index of the hpet device
to mmap is passed from kernel to userspace, index might be changed and
libc invalidates its mapping as needed.

Remove cpu_fill_vdso_timehands() KPI, instead require that
timecounters which can be used from userspace, to provide
tc_fill_vdso_timehands{,32}() methods.  Merge i386 and amd64
libc/<arch>/sys/__vdso_gettc.c into one source file in the new
libc/x86/sys location.  __vdso_gettc() internal interface is changed
to move timecounter algorithm detection into the MD code.

Measurements show that RDTSC even with the syscall overhead is faster
than userspace HPET access.  But still, userspace HPET is three-four
times faster than syscall HPET on several Core2 and SandyBridge
machines.

Tested by:	Howard Su <howard0su@gmail.com>
Sponsored by:	The FreeBSD Foundation
MFC after:	1 month
Differential revision:	https://reviews.freebsd.org/D7473
2016-08-17 09:52:09 +00:00
Konstantin Belousov
50c22263bb Cache getbintime(9) answer in timehands, similarly to getnanotime(9)
and getmicrotime(9).

Suggested and reviewed by:	bde (previous version)
Sponsored by:	The FreeBSD Foundation
MFC after:	1 month
2016-07-30 09:25:57 +00:00
Konstantin Belousov
5760b029ee Prevent parallel tc_windup() calls, both parallel top-level calls from
setclock() and from simultaneous top-level and interrupt.  For this,
tc_windup() is protected with a tc_setclock_mtx spinlock, in the try
mode when called from hardclock interrupt.  If spinlock cannot be
obtained without spinning from the interrupt context, this means that
top-level executes tc_windup() on other core and our try may be
avoided.

The boottimebin and boottime variables should be adjusted from
tc_windup().  To be correct, they must be part of the timehands and
read using lockless protocol.  Remove the globals and reimplement the
getboottime(9)/getboottimebin(9) KPI using the timehands read
protocol.

Tested by:	pho (as part of the whole patch)
Reviewed by:	jhb (same)
Discussed wit:	bde
Sponsored by:	The FreeBSD Foundation
MFC after:	1 month
X-Differential revision:	https://reviews.freebsd.org/D7302
2016-07-27 11:49:41 +00:00
Konstantin Belousov
4d29106e55 Style.
Sponsored by:	The FreeBSD Foundation
MFC after:	1 month
X-Differential revision:	https://reviews.freebsd.org/D7302
2016-07-27 11:33:33 +00:00
Konstantin Belousov
a83c016f00 Reduce number of timehands to just two. This is useful because
consumers can now be only one tc_windup() call late.

Use C99 initialization.

Tested by:	pho (as part of the whole patch)
Reviewed by:	jhb (same)
Discussed with:	bde
Sponsored by:	The FreeBSD Foundation
MFC after:	1 month
X-Differential revision:	https://reviews.freebsd.org/D7302
2016-07-27 11:27:52 +00:00
Konstantin Belousov
584b675ed6 Hide the boottime and bootimebin globals, provide the getboottime(9)
and getboottimebin(9) KPI. Change consumers of boottime to use the
KPI.  The variables were renamed to avoid shadowing issues with local
variables of the same name.

Issue is that boottime* should be adjusted from tc_windup(), which
requires them to be members of the timehands structure.  As a
preparation, this commit only introduces the interface.

Some uses of boottime were found doubtful, e.g. NLM uses boottime to
identify the system boot instance.  Arguably the identity should not
change on the leap second adjustment, but the commit is about the
timekeeping code and the consumers were kept bug-to-bug compatible.

Tested by:	pho (as part of the bigger patch)
Reviewed by:	jhb (same)
Discussed with:	bde
Sponsored by:	The FreeBSD Foundation
MFC after:	1 month
X-Differential revision:	https://reviews.freebsd.org/D7302
2016-07-27 11:08:59 +00:00
Pedro F. Giffuni
e3043798aa sys/kern: spelling fixes in comments.
No functional change.
2016-04-29 22:15:33 +00:00
Enji Cooper
aaca704590 Define fhard in pps_event(..) only when PPS_SYNC is defined to mute
an -Wunused-but-set-variable warning

Reported by: FreeBSD_HEAD_amd64_gcc4.9 jenkins job
Sponsored by: EMC / Isilon Storage Division
2015-11-02 03:14:37 +00:00
Konstantin Belousov
b2557db607 Use per-cpu values for base and last in tc_cpu_ticks(). The values
are updated lockess, different CPUs write its own view of timecounter
state.  The critical section is done for safety, callers of
tc_cpu_ticks() are supposed to already enter critical section, or to
own a spinlock.

The change fixes sporadical reports of too high values reported for
the (W)CPU on platforms that do not provide cpu ticker and use
tc_cpu_ticks(), in particular, arm*.

Diagnosed and reviewed by:	jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2015-09-25 13:03:57 +00:00
Ian Lepore
e8bac3f240 If a specific timecounter has been chosen via sysctl, and a new timecounter
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).
2015-08-12 20:50:20 +00:00
Ian Lepore
721b581722 Only process the PPS event types currently enabled in pps_params.mode.
This makes the PPS API behave correctly, but isn't ideal -- we still end
up capturing PPS data for non-enabled edges, we just don't process the
data into an event that becomes visible outside of kern_tc.  That's because
the event type isn't passed to pps_capture(), so it can't do the filtering.
Any solution for capture filtering is going to require touching every driver.
2015-08-07 23:31:31 +00:00
Ian Lepore
6f7a9f7c8d RFC 2783 requires a status of ETIMEDOUT, not EWOULDBLOCK, on a timeout. 2015-08-07 21:14:19 +00:00
Konstantin Belousov
f4b5a9725a Reimplement the ordering requirements for the timehands updates, and
for timehands consumers, by using fences.

Ensure that the timehands->th_generation reset to zero is visible
before the data update is visible [*].  tc_setget() allowed data update
writes to become visible before generation (but not on TSO
architectures).

Remove tc_setgen(), tc_getgen() helpers, use atomics inline [**].

Noted by:	alc [*]
Requested by:	bde [**]
Reviewed by:	alc, bde
Sponsored by:	The FreeBSD Foundation
MFC after:	3 weeks
2015-07-08 18:42:08 +00:00
Konstantin Belousov
529c97886b Tweaks for r284178:
Do not include machine/atomic.h explicitely, the header is already included
by sys/systm.h.

Force inlining of tc_getgen() and tc_setgen().  The functions are used
more than once, which causes compilers with non-aggressive inlining
policies to generate calls.

Suggested by:	bde
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2015-06-11 04:41:54 +00:00
Konstantin Belousov
2c6946dca2 When updating/accessing the timehands, barriers are needed to ensure
that:
- th_generation update is visible after the parameters update is
  visible;
- the read of parameters is not reordered before initial read of
  th_generation.

On UP kernels, compiler barriers are enough.  For SMP machines, CPU
barriers must be used too, as was confirmed by submitter by testing on
the Freescale T4240 platform with 24 PowerPC processors.

Submitted by:	Sebastian Huber <sebastian.huber@embedded-brains.de>
MFC after:	1 week
2015-06-09 11:49:56 +00:00
Ian Lepore
28315e27a7 Implement a mechanism for making changes in the kernel<->driver PPS
interface without breaking ABI or API compatibility with existing drivers.

The existing data structures used to communicate between the kernel and
driver portions of PPS processing contain no spare/padding fields and no
flags field or other straightforward mechanism for communicating changes
in the structures or behaviors of the code.  This makes it difficult to
MFC new features added to the PPS facility.  ABI compatibility is
important; out-of-tree drivers in module form are known to exist.  (Note
that the existing api_version field in the pps_params structure must
contain the value mandated by RFC 2783 and any RFCs that come along after.)

These changes introduce a pair of abi-version fields which are filled in
by the driver and the kernel respectively to indicate the interface
version.  The driver sets its version field before calling the new
pps_init_abi() function.  That lets the kernel know how much of the
pps_state structure is understood by the driver and it can avoid using
newer fields at the end of the structure that it knows about if the driver
is a lower version.  The kernel fills in its version field during the init
call, letting the driver know what features and data the kernel supports.

To implement the new version information in a way that is backwards
compatible with code from before these changes, the high bit of the
lightly-used 'kcmode' field is repurposed as a flag bit that indicates the
driver is aware of the abi versioning scheme.  Basically if this bit is
clear that indicates a "version 0" driver and if it is set the driver_abi
field indicates the version.

These changes also move the recently-added 'mtx' field of pps_state from
the middle to the end of the structure, and make the kernel code that uses
this field conditional on the driver being abi version 1 or higher.  It
changes the only driver currently supplying the mtx field, usb_serial, to
use pps_init_abi().

Reviewed by:	hselasky@
2015-05-04 17:59:39 +00:00
Ian Lepore
91d9eda200 Use sbuf_printf() for sysctl strings instead of stack buffers and snprintf(). 2015-03-14 23:16:12 +00:00
Hans Petter Selasky
35ee8a4a59 Add mutex support to the pps_ioctl() API in the kernel.
Bump kernel version to reflect structure change.

PR:		196897
MFC after:	1 week
2015-03-07 18:23:32 +00:00
Neel Natu
d1b1b60065 Update the vdso timehands only via tc_windup().
Prior to this change CLOCK_MONOTONIC could go backwards when the timecounter
hardware was changed via 'sysctl kern.timecounter.hardware'. This happened
because the vdso timehands update was missing the special treatment in
tc_windup() when changing timecounters.

Reviewed by:	kib
2015-01-20 03:54:30 +00:00
John Baldwin
92597e064b On some Intel CPUs with a P-state but not C-state invariant TSC the TSC
may also halt in C2 and not just C3 (it seems that in some cases the BIOS
advertises its C3 state as a C2 state in _CST).  Just play it safe and
disable both C2 and C3 states if a user forces the use of the TSC as the
timecounter on such CPUs.

PR:		192316
Differential Revision:	https://reviews.freebsd.org/D1441
No objection from:	jkim
MFC after:	1 week
2015-01-05 20:44:44 +00:00
Hans Petter Selasky
af3b2549c4 Pull in r267961 and r267973 again. Fix for issues reported will follow. 2014-06-28 03:56:17 +00:00
Glen Barber
37a107a407 Revert r267961, r267973:
These changes prevent sysctl(8) from returning proper output,
such as:

 1) no output from sysctl(8)
 2) erroneously returning ENOMEM with tools like truss(1)
    or uname(1)
 truss: can not get etype: Cannot allocate memory
2014-06-27 22:05:21 +00:00
Hans Petter Selasky
3da1cf1e88 Extend the meaning of the CTLFLAG_TUN flag to automatically check if
there is an environment variable which shall initialize the SYSCTL
during early boot. This works for all SYSCTL types both statically and
dynamically created ones, except for the SYSCTL NODE type and SYSCTLs
which belong to VNETs. A new flag, CTLFLAG_NOFETCH, has been added to
be used in the case a tunable sysctl has a custom initialisation
function allowing the sysctl to still be marked as a tunable. The
kernel SYSCTL API is mostly the same, with a few exceptions for some
special operations like iterating childrens of a static/extern SYSCTL
node. This operation should probably be made into a factored out
common macro, hence some device drivers use this. The reason for
changing the SYSCTL API was the need for a SYSCTL parent OID pointer
and not only the SYSCTL parent OID list pointer in order to quickly
generate the sysctl path. The motivation behind this patch is to avoid
parameter loading cludges inside the OFED driver subsystem. Instead of
adding special code to the OFED driver subsystem to post-load tunables
into dynamically created sysctls, we generalize this in the kernel.

Other changes:
- Corrected a possibly incorrect sysctl name from "hw.cbb.intr_mask"
to "hw.pcic.intr_mask".
- Removed redundant TUNABLE statements throughout the kernel.
- Some minor code rewrites in connection to removing not needed
TUNABLE statements.
- Added a missing SYSCTL_DECL().
- Wrapped two very long lines.
- Avoid malloc()/free() inside sysctl string handling, in case it is
called to initialize a sysctl from a tunable, hence malloc()/free() is
not ready when sysctls from the sysctl dataset are registered.
- Bumped FreeBSD version to indicate SYSCTL API change.

MFC after:	2 weeks
Sponsored by:	Mellanox Technologies
2014-06-27 16:33:43 +00:00
Davide Italiano
5b999a6be0 - Make callout(9) tickless, relying on eventtimers(4) as backend for
precise time event generation. This greatly improves granularity of
callouts which are not anymore constrained to wait next tick to be
scheduled.
- Extend the callout KPI introducing a set of callout_reset_sbt* functions,
which take a sbintime_t as timeout argument. The new KPI also offers a
way for consumers to specify precision tolerance they allow, so that
callout can coalesce events and reduce number of interrupts as well as
potentially avoid scheduling a SWI thread.
- Introduce support for dispatching callouts directly from hardware
interrupt context, specifying an additional flag. This feature should be
used carefully, as long as interrupt context has some limitations
(e.g. no sleeping locks can be held).
- Enhance mechanisms to gather informations about callwheel, introducing
a new sysctl to obtain stats.

This change breaks the KBI. struct callout fields has been changed, in
particular 'int ticks' (4 bytes) has been replaced with 'sbintime_t'
(8 bytes) and another 'sbintime_t' field was added for precision.

Together with:	mav
Reviewed by:	attilio, bde, luigi, phk
Sponsored by:	Google Summer of Code 2012, iXsystems inc.
Tested by:	flo (amd64, sparc64), marius (sparc64), ian (arm),
		markj (amd64), mav, Fabian Keil
2013-03-04 11:09:56 +00:00
Ian Lepore
a1137de941 Add PPS_CANWAIT support for time_pps_fetch(). This adds support for all three
blocking modes described in section 3.4.3 of RFC 2783, allowing the caller
to retrieve the most recent values without blocking, to block for a specified
time, or to block forever.

Reviewed by:	discussion on hackers@
2013-02-15 18:30:32 +00:00
John Baldwin
a8df530ddc Mark 'ticks', 'time_second', and 'time_uptime' as volatile to prevent the
compiler from caching their values in tight loops.

Reviewed by:	bde
MFC after:	1 week
2013-01-28 19:38:13 +00:00
George V. Neville-Neil
57d025c338 Add support for walltimestamp in DTrace.
Submitted by:	Fabian Keil
MFC after:	2 weeks
2012-07-16 20:17:19 +00:00
Konstantin Belousov
21c295ef88 Stop updating the struct vdso_timehands from even handler executed in
the scheduled task from tc_windup(). Do it directly from tc_windup in
interrupt context [1].

Establish the permanent mapping of the shared page into the kernel
address space, avoiding the potential need to sleep waiting for
allocation of sf buffer during vdso_timehands update. As a
consequence, shared_page_write_start() and shared_page_write_end()
functions are not needed anymore.

Guess and memorize the pointers to native host and compat32 sysentvec
during initialization, to avoid the need to get shared_page_alloc_sx
lock during the update.

In tc_fill_vdso_timehands(), do not loop waiting for timehands
generation to stabilize, since vdso_timehands is written in the same
interrupt context which wrote timehands.

Requested by:	  mav [1]
MFC after:	  29 days
2012-06-23 09:33:06 +00:00
Konstantin Belousov
aea810386d Implement mechanism to export some kernel timekeeping data to
usermode, using shared page.  The structures and functions have vdso
prefix, to indicate the intended location of the code in some future.

The versioned per-algorithm data is exported in the format of struct
vdso_timehands, which mostly repeats the content of in-kernel struct
timehands. Usermode reading of the structure can be lockless.
Compatibility export for 32bit processes on 64bit host is also
provided. Kernel also provides usermode with indication about
currently used timecounter, so that libc can fall back to syscall if
configured timecounter is unknown to usermode code.

The shared data updates are initiated both from the tc_windup(), where
a fast task is queued to do the update, and from sysctl handlers which
change timecounter. A manual override switch
kern.timecounter.fast_gettime allows to turn off the mechanism.

Only x86 architectures export the real algorithm data, and there, only
for tsc timecounter. HPET counters page could be exported as well, but
I prefer to not further glue the kernel and libc ABI there until
proper vdso-based solution is developed.

Minimal stubs neccessary for non-x86 architectures to still compile
are provided.

Discussed with:	bde
Reviewed by:	jhb
Tested by:	flo
MFC after:	1 month
2012-06-22 07:06:40 +00:00
Juli Mallett
9624d94701 o) Add COMPAT_FREEBSD32 support for MIPS kernels using the n64 ABI with userlands
using the o32 ABI.  This mostly follows nwhitehorn's lead in implementing
   COMPAT_FREEBSD32 on powerpc64.
o) Add a new type to the freebsd32 compat layer, time32_t, which is time_t in the
   32-bit ABI being used.  Since the MIPS port is relatively-new, even the 32-bit
   ABIs use a 64-bit time_t.
o) Because time{spec,val}32 has the same size and layout as time{spec,val} on MIPS
   with 32-bit compatibility, then, disable some code which assumes otherwise
   wrongly when built for MIPS.  A more general macro to check in this case would
   seem like a good idea eventually.  If someone adds support for using n32
   userland with n64 kernels on MIPS, then they will have to add a variety of
   flags related to each piece of the ABI that can vary.  That's probably the
   right time to generalize further.
o) Add MIPS to the list of architectures which use PAD64_REQUIRED in the
   freebsd32 compat code.  Probably this should be generalized at some point.

Reviewed by:	gonzo
2012-03-03 08:19:18 +00:00
Kevin Lo
de02885a7b Add a missing break. This bug was introduced in r228856. 2012-02-10 06:30:52 +00:00
Lawrence Stewart
6cedd609b7 Introduce the sysclock_getsnapshot() and sysclock_snap2bintime() KPIs. The
sysclock_getsnapshot() function allows the caller to obtain a snapshot of all
the system clock and timecounter state required to create time stamps at a later
point. The sysclock_snap2bintime() function converts a previously obtained
snapshot into a bintime time stamp according to the specified flags e.g. which
system clock, uptime vs absolute time, etc.

These KPIs enable useful functionality, including direct comparison of the
feedback and feed-forward system clocks and generation of multiple time stamps
with different formats from a single timecounter read.

Committed on behalf of Julien Ridoux and Darryl Veitch from the University of
Melbourne, Australia, as part of the FreeBSD Foundation funded "Feed-Forward
Clock Synchronization Algorithms" project.

For more information, see http://www.synclab.org/radclock/

In collaboration with:	Julien Ridoux (jridoux at unimelb edu au)
2011-12-24 01:32:01 +00:00
Lawrence Stewart
88394fe42c Do away with the somewhat clunky sysclock_ops structure and associated code,
reimplementing the [get]{bin,nano,micro}[up]time() wrapper functions in terms of
the new "fromclock" API instead.

Committed on behalf of Julien Ridoux and Darryl Veitch from the University of
Melbourne, Australia, as part of the FreeBSD Foundation funded "Feed-Forward
Clock Synchronization Algorithms" project.

For more information, see http://www.synclab.org/radclock/

Discussed with:	Julien Ridoux (jridoux at unimelb edu au)
Submitted by:	Julien Ridoux (jridoux at unimelb edu au)
2011-11-29 08:33:40 +00:00
Lawrence Stewart
e977bac333 Make the fbclock_[get]{bin,nano,micro}[up]time() function prototypes public so
that new APIs with some performance sensitivity can be built on top of them.
These functions should not be called directly except in special circumstances.

Committed on behalf of Julien Ridoux and Darryl Veitch from the University of
Melbourne, Australia, as part of the FreeBSD Foundation funded "Feed-Forward
Clock Synchronization Algorithms" project.

For more information, see http://www.synclab.org/radclock/

Discussed with:	Julien Ridoux (jridoux at unimelb edu au)
Submitted by:	Julien Ridoux (jridoux at unimelb edu au)
2011-11-29 06:53:36 +00:00
Lawrence Stewart
c2a4ee9906 Fix an oversight in r227747 by calling fbclock_bin{up}time() directly from the
fbclock_{nanouptime|microuptime|bintime|nanotime|microtime}() functions to avoid
indirecting through a sysclock_ops wrapper function.

Committed on behalf of Julien Ridoux and Darryl Veitch from the University of
Melbourne, Australia, as part of the FreeBSD Foundation funded "Feed-Forward
Clock Synchronization Algorithms" project.

For more information, see http://www.synclab.org/radclock/

Submitted by:	Julien Ridoux (jridoux at unimelb edu au)
2011-11-29 06:12:19 +00:00
Lawrence Stewart
65e359a15c - Add Pulse-Per-Second timestamping using raw ffcounter and corresponding
ffclock time in seconds.

- Add IOCTL to retrieve ffclock timestamps from userland.

Committed on behalf of Julien Ridoux and Darryl Veitch from the University of
Melbourne, Australia, as part of the FreeBSD Foundation funded "Feed-Forward
Clock Synchronization Algorithms" project.

For more information, see http://www.synclab.org/radclock/

Submitted by:	Julien Ridoux (jridoux at unimelb edu au)
2011-11-21 13:34:29 +00:00
Lawrence Stewart
9bce0f05fe - Provide a sysctl interface to change the active system clock at runtime.
- Wrap [get]{bin,nano,micro}[up]time() functions of sys/time.h to allow
  requesting time from either the feedback or the feed-forward clock. If a
  feedback (e.g. ntpd) and feed-forward (e.g. radclock) daemon are both running
  on the system, both kernel clocks are updated but only one serves time.

- Add similar wrappers for the feed-forward difference clock.

Committed on behalf of Julien Ridoux and Darryl Veitch from the University of
Melbourne, Australia, as part of the FreeBSD Foundation funded "Feed-Forward
Clock Synchronization Algorithms" project.

For more information, see http://www.synclab.org/radclock/

Submitted by:	Julien Ridoux (jridoux at unimelb edu au)
2011-11-20 05:32:12 +00:00
Lawrence Stewart
b0fdc83713 Core structure and functions to support a feed-forward clock within the kernel.
Implement ffcounter, a monotonically increasing cumulative counter on top of the
active timecounter. Provide low-level functions to read the ffcounter and
convert it to absolute time or a time interval in seconds using the current
ffclock estimates, which track the drift of the oscillator. Add a ring of
fftimehands to track passing of time on each kernel tick and pick up updates of
ffclock estimates.

Committed on behalf of Julien Ridoux and Darryl Veitch from the University of
Melbourne, Australia, as part of the FreeBSD Foundation funded "Feed-Forward
Clock Synchronization Algorithms" project.

For more information, see http://www.synclab.org/radclock/

Submitted by:	Julien Ridoux (jridoux at unimelb edu au)
2011-11-19 14:10:16 +00:00
Ed Schouten
6472ac3d8a Mark all SYSCTL_NODEs static that have no corresponding SYSCTL_DECLs.
The SYSCTL_NODE macro defines a list that stores all child-elements of
that node. If there's no SYSCTL_DECL macro anywhere else, there's no
reason why it shouldn't be static.
2011-11-07 15:43:11 +00:00