linux-stable.git/include/linux/ktime.h, branch v4.0.4 Linux kernel stable tree Merge tag 'fortglx-3.20-time' of https://git.linaro.org/people/john.stultz/linux into timers/core 2015-01-24T09:11:12+00:00 Thomas Gleixner tglx@linutronix.de 2015-01-24T09:11:12+00:00 fe31fca35d6af9176eec0024fac2ceeaacbc8639 Pull time updates from John Stultz for 3.20: * ktime division optimization * Expose a few more y2038-safe timekeeping interfaces * RTC core changes to address y2038 
Pull time updates from John Stultz for 3.20:

 * ktime division optimization
 * Expose a few more y2038-safe timekeeping interfaces
 * RTC core changes to address y2038
ktime: Optimize ktime_divns for constant divisors 2015-01-24T01:21:31+00:00 Nicolas Pitre nicolas.pitre@linaro.org 2014-12-03T19:43:06+00:00 8b618628b2bf83512fc8df5e8672619d65adfdfb At least on ARM, do_div() is optimized to turn constant divisors into an inline multiplication by the reciprocal value at compile time. However this optimization is missed entirely whenever ktime_divns() is used and the slow out-of-line division code is used all the time. Let ktime_divns() use do_div() inline whenever the divisor is constant and small enough. This will make things like ktime_to_us() and ktime_to_ms() much faster. Cc: Arnd Bergmann <arnd.bergmann@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Nicolas Pitre <nico@linaro.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: John Stultz <john.stultz@linaro.org> 
At least on ARM, do_div() is optimized to turn constant divisors into
an inline multiplication by the reciprocal value at compile time.
However this optimization is missed entirely whenever ktime_divns() is
used and the slow out-of-line division code is used all the time.

Let ktime_divns() use do_div() inline whenever the divisor is constant
and small enough.  This will make things like ktime_to_us() and
ktime_to_ms() much faster.

Cc: Arnd Bergmann <arnd.bergmann@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Nicolas Pitre <nico@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
ktime.h: Introduce ktime_ms_delta 2015-01-23T10:47:15+00:00 Chunyan Zhang zhang.chunyan@linaro.org 2014-12-17T05:11:35+00:00 41fbf3b39d5eca01527338b4d0ee15ee1ae1023c This patch adds a reusable time difference function which returns the difference in millisecond, as often used in some driver code, e.g. mtd/test, media/rc, etc. Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org> Acked-by: Arnd Bergmann <arnd@linaro.org> Cc: zhang.lyra@gmail.com Cc: davem@davemloft.net Cc: john.stultz@linaro.org Cc: dborkman@redhat.com Link: http://lkml.kernel.org/r/1418793095-18780-1-git-send-email-zhang.chunyan@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de> 
This patch adds a reusable time difference function which returns the
difference in millisecond, as often used in some driver code, e.g.
mtd/test, media/rc, etc.

Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Acked-by: Arnd Bergmann <arnd@linaro.org>
Cc: zhang.lyra@gmail.com
Cc: davem@davemloft.net
Cc: john.stultz@linaro.org
Cc: dborkman@redhat.com
Link: http://lkml.kernel.org/r/1418793095-18780-1-git-send-email-zhang.chunyan@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
time: Consolidate the time accessor prototypes 2014-07-23T17:17:54+00:00 Thomas Gleixner tglx@linutronix.de 2014-07-16T21:04:02+00:00 8b094cd03b4a3793220d8d8d86a173bfea8c285b Right now we have time related prototypes in 3 different header files. Move it to a single timekeeping header file and move the core internal stuff into a core private header. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org> 
Right now we have time related prototypes in 3 different header
files. Move it to a single timekeeping header file and move the core
internal stuff into a core private header.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
time: More core infrastructure for timespec64 2014-07-23T17:17:53+00:00 John Stultz john.stultz@linaro.org 2014-07-16T21:03:59+00:00 49cd6f869984692547c57621bf42697aaa7f5622 Helper and conversion functions for timespec64. Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org> 
Helper and conversion functions for timespec64.

Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
ktime: Change ktime_set() to take 64bit seconds value 2014-07-23T17:16:50+00:00 John Stultz john.stultz@linaro.org 2014-07-16T21:03:56+00:00 b17b20d70dcbe48dd1aa6aba073a60ddfce5d7db In order to support dates past 2038 on 32bit systems, ktime_set() needs to handle 64bit second values. [ tglx: Removed the BITS_PER_LONG check ] Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org> 
In order to support dates past 2038 on 32bit systems, ktime_set()
needs to handle 64bit second values.

[ tglx: Removed the BITS_PER_LONG check ]

Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
ktime: Sanitize ktime_to_us/ms conversion 2014-07-23T17:16:50+00:00 Thomas Gleixner tglx@linutronix.de 2014-07-16T21:03:55+00:00 166afb64511eef08e13331b970c44fe91cea45ef With the plain nanoseconds based ktime_t we can simply use ktime_divns() instead of going through loops and hoops of timespec/timeval conversion. Reported-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org> 
With the plain nanoseconds based ktime_t we can simply use
ktime_divns() instead of going through loops and hoops of
timespec/timeval conversion.

Reported-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
ktime: Kill non-scalar ktime_t implementation for 2038 2014-07-23T17:16:50+00:00 John Stultz john.stultz@linaro.org 2014-07-16T21:03:53+00:00 24e4a8c3e8868874835b0f1ad6dd417341e99822 The non-scalar ktime_t implementation is basically a timespec which has to be changed to support dates past 2038 on 32bit systems. This patch removes the non-scalar ktime_t implementation, forcing the scalar s64 nanosecond version on all architectures. This may have additional performance overhead on some 32bit systems when converting between ktime_t and timespec structures, however the majority of 32bit systems (arm and i386) were already using scalar ktime_t, so no performance regressions will be seen on those platforms. On affected platforms, I'm open to finding optimizations, including avoiding converting to timespecs where possible. [ tglx: We can now cleanup the ktime_t.tv64 mess, but thats a different issue and we can throw a coccinelle script at it ] Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org> 
The non-scalar ktime_t implementation is basically a timespec
which has to be changed to support dates past 2038 on 32bit
systems.

This patch removes the non-scalar ktime_t implementation, forcing
the scalar s64 nanosecond version on all architectures.

This may have additional performance overhead on some 32bit
systems when converting between ktime_t and timespec structures,
however the majority of 32bit systems (arm and i386) were already
using scalar ktime_t, so no performance regressions will be seen
on those platforms.

On affected platforms, I'm open to finding optimizations, including
avoiding converting to timespecs where possible.

[ tglx: We can now cleanup the ktime_t.tv64 mess, but thats a
  different issue and we can throw a coccinelle script at it ]

Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
ktime: add ktime_after and ktime_before helper 2014-06-11T19:23:17+00:00 Daniel Borkmann dborkman@redhat.com 2014-06-11T16:19:28+00:00 67cb9366ff5f99868100198efba5ca88aaa6ad25 Add two minimal helper functions analogous to time_before() and time_after() that will later on both be needed by SCTP code. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Add two minimal helper functions analogous to time_before() and
time_after() that will later on both be needed by SCTP code.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ktime: fix some scripts/kernel-doc warnings 2013-07-25T10:35:39+00:00 Yacine Belkadi yacine.belkadi.1@gmail.com 2013-07-25T06:11:53+00:00 36019265cf81cdb2d366b28016bb00b936efc751 When building the htmldocs (in verbose mode), scripts/kernel-doc reports the following type of warnings: Warning(include/linux/ktime.h:75): No description found for return value of 'ktime_set' Fix them by using a "Return:" section to describe the return values. (Also apply some minor reformatting along the way.) Signed-off-by: Yacine Belkadi <yacine.belkadi.1@gmail.com> Acked-by: Rob Landley <rob@landley.net> Signed-off-by: Jiri Kosina <jkosina@suse.cz> 
When building the htmldocs (in verbose mode), scripts/kernel-doc reports the
following type of warnings:
Warning(include/linux/ktime.h:75): No description found for return value of
'ktime_set'

Fix them by using a "Return:" section to describe the return values.
(Also apply some minor reformatting along the way.)

Signed-off-by: Yacine Belkadi <yacine.belkadi.1@gmail.com>
Acked-by: Rob Landley <rob@landley.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>