linux.git/arch/ia64/kernel/time.c, branch v4.17

ia64, sched/cputime: Fix build error if CONFIG_VIRT_CPU_ACCOUNTING_NATIVE=y

2018-01-06T10:48:34+00:00

Remove the extra parenthesis.

This bug was introduced by:

  e2339a4caa5e: ("ia64: Convert vtime to use nsec units directly")

Signed-off-by: Valentin Ilie 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: fenghua.yu@intel.com
Cc: linux-ia64@vger.kernel.org
Cc: tony.luck@intel.com
Link: http://lkml.kernel.org/r/1515193979-24873-1-git-send-email-valentin.ilie@gmail.com
Signed-off-by: Ingo Molnar

ia64: Update fsyscall gettime to use modern vsyscall_update

2017-10-31T17:58:36+00:00

John Stultz provided the outline for this patch back in May 2014 here:

	http://patches.linaro.org/patch/30501/

but I let this sit on the shelf for too long and in the intervening
years almost every field in "struct timekeeper" was changed. So this
is almost completely different from his original. Though the key change
in arch/ia64/kernel/fsys.S remains the same.

The core logic change with the updated vsyscall method is that we
preserve the base nanosecond value in shifted nanoseconds, which
allows us to avoid truncating and rounding up to the next nanosecond
every tick to avoid inconsistencies.

Thus the logic moved from
nsec = ((cycle_delta * mult)>>shift) + base_nsec;
to
nsec = ((cycle_delta * mult) + base_snsec) >> shift;

Cc: John Stultz 
Cc: linux-ia64@vger.kernel.org
Signed-off-by: Tony Luck

sched/headers: Prepare to move cputime functionality from into

2017-03-02T07:42:39+00:00

Introduce a trivial, mostly empty  header
to prepare for the moving of cputime functionality out of sched.h.

Update all code that relies on these facilities.

Acked-by: Linus Torvalds 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

sched/headers: Prepare for new header dependencies before moving code to

2017-03-02T07:42:30+00:00

We are going to move softlockup APIs out of , which
will have to be picked up from other headers and a couple of .c files.

 already includes .

Include the  header in the files that are going to need it.

Acked-by: Linus Torvalds 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

ia64: Convert vtime to use nsec units directly

2017-02-01T08:14:02+00:00

There is no need anymore for this cputime_t midlayer. Let's use nsec
units directly.

Signed-off-by: Frederic Weisbecker 
Cc: Benjamin Herrenschmidt 
Cc: Fenghua Yu 
Cc: Heiko Carstens 
Cc: Linus Torvalds 
Cc: Martin Schwidefsky 
Cc: Michael Ellerman 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Rik van Riel 
Cc: Stanislaw Gruszka 
Cc: Thomas Gleixner 
Cc: Tony Luck 
Cc: Wanpeng Li 
Link: http://lkml.kernel.org/r/1485832191-26889-30-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar

sched/cputime: Push time to account_system_time() in nsecs

2017-02-01T08:13:58+00:00

This is one more step toward converting cputime accounting to pure nsecs.

Signed-off-by: Frederic Weisbecker 
Cc: Benjamin Herrenschmidt 
Cc: Fenghua Yu 
Cc: Heiko Carstens 
Cc: Linus Torvalds 
Cc: Martin Schwidefsky 
Cc: Michael Ellerman 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Rik van Riel 
Cc: Stanislaw Gruszka 
Cc: Thomas Gleixner 
Cc: Tony Luck 
Cc: Wanpeng Li 
Link: http://lkml.kernel.org/r/1485832191-26889-25-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar

sched/cputime: Push time to account_idle_time() in nsecs

2017-02-01T08:13:57+00:00

This is one more step toward converting cputime accounting to pure nsecs.

Signed-off-by: Frederic Weisbecker 
Cc: Benjamin Herrenschmidt 
Cc: Fenghua Yu 
Cc: Heiko Carstens 
Cc: Linus Torvalds 
Cc: Martin Schwidefsky 
Cc: Michael Ellerman 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Rik van Riel 
Cc: Stanislaw Gruszka 
Cc: Thomas Gleixner 
Cc: Tony Luck 
Cc: Wanpeng Li 
Link: http://lkml.kernel.org/r/1485832191-26889-24-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar

sched/cputime: Push time to account_user_time() in nsecs

2017-02-01T08:13:56+00:00

This is one more step toward converting cputime accounting to pure nsecs.

Signed-off-by: Frederic Weisbecker 
Cc: Benjamin Herrenschmidt 
Cc: Fenghua Yu 
Cc: Heiko Carstens 
Cc: Linus Torvalds 
Cc: Martin Schwidefsky 
Cc: Michael Ellerman 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Rik van Riel 
Cc: Stanislaw Gruszka 
Cc: Thomas Gleixner 
Cc: Tony Luck 
Cc: Wanpeng Li 
Link: http://lkml.kernel.org/r/1485832191-26889-22-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar

sched/cputime: Rename vtime_account_user() to vtime_flush()

2017-01-14T08:54:13+00:00

CONFIG_VIRT_CPU_ACCOUNTING_NATIVE=y used to accumulate user time and
account it on ticks and context switches only through the
vtime_account_user() function.

Now this model has been generalized on the 3 archs for all kind of
cputime (system, irq, ...) and all the cputime flushing happens under
vtime_account_user().

So let's rename this function to better reflect its new role.

Signed-off-by: Frederic Weisbecker 
Acked-by: Thomas Gleixner 
Acked-by: Martin Schwidefsky 
Cc: Benjamin Herrenschmidt 
Cc: Christian Borntraeger 
Cc: Fenghua Yu 
Cc: Heiko Carstens 
Cc: Linus Torvalds 
Cc: Michael Ellerman 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Rik van Riel 
Cc: Stanislaw Gruszka 
Cc: Tony Luck 
Cc: Wanpeng Li 
Link: http://lkml.kernel.org/r/1483636310-6557-11-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar

sched/cputime, ia64: Accumulate cputime and account only on tick/task switch

2017-01-14T08:54:12+00:00

Currently CONFIG_VIRT_CPU_ACCOUNTING_NATIVE=y accounts the cputime on
any context boundary: irq entry/exit, guest entry/exit, context switch,
etc...

Calling functions such as account_system_time(), account_user_time()
and such can be costly, especially if they are called on many fastpath
such as twice per IRQ. Those functions do more than just accounting to
kcpustat and task cputime. Depending on the config, some subsystems can
perform unpleasant multiplications and divisions, among other things.

So lets accumulate the cputime instead and delay the accounting on ticks
and context switches only.

Signed-off-by: Frederic Weisbecker 
Acked-by: Thomas Gleixner 
Cc: Benjamin Herrenschmidt 
Cc: Christian Borntraeger 
Cc: Fenghua Yu 
Cc: Heiko Carstens 
Cc: Linus Torvalds 
Cc: Martin Schwidefsky 
Cc: Michael Ellerman 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Rik van Riel 
Cc: Stanislaw Gruszka 
Cc: Tony Luck 
Cc: Wanpeng Li 
Link: http://lkml.kernel.org/r/1483636310-6557-9-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar