All of lore.kernel.org
 help / color / mirror / Atom feed
* [lkp] [+64 bytes kernel size regression] [i386-tinyconfig] [78532abaf5] x86/tsc: Add option to force frequency recalibration with HW timer
@ 2023-01-07  9:03 kernel test robot
  2023-01-07 16:01 ` Paul E. McKenney
  0 siblings, 1 reply; 4+ messages in thread
From: kernel test robot @ 2023-01-07  9:03 UTC (permalink / raw)
  To: Paul E. McKenney, Feng Tang; +Cc: lkp, oe-kbuild-all


FYI, we noticed a +64 bytes kernel size regression due to commit:

commit: 78532abaf5f1c973c99680960ae22bd797951ddf (x86/tsc: Add option to force frequency recalibration with HW timer)
https://git.kernel.org/cgit/linux/kernel/git/paulmck/linux-rcu.git workqueue.2023.01.06a


Details as below (size data is obtained by `nm --size-sort vmlinux`):

8913f44d: clocksource: Permit limited-duration clocksource watchdogging
78532aba: x86/tsc: Add option to force frequency recalibration with HW timer

+----------------------------------+----------+----------+-------+
|              symbol              | 8913f44d | 78532aba | delta |
+----------------------------------+----------+----------+-------+
| bzImage                          | 495904   | 495968   | 64    |
| nm.t.tsc_setup                   | 103      | 129      | 26    |
| nm.t.init_tsc_clocksource        | 111      | 132      | 21    |
| nm.t.tsc_refine_calibration_work | 427      | 440      | 13    |
| nm.d.tsc_force_recalibrate       | 0        | 4        | 4     |
+----------------------------------+----------+----------+-------+



Thanks


^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [lkp] [+64 bytes kernel size regression] [i386-tinyconfig] [78532abaf5] x86/tsc: Add option to force frequency recalibration with HW timer
  2023-01-07  9:03 [lkp] [+64 bytes kernel size regression] [i386-tinyconfig] [78532abaf5] x86/tsc: Add option to force frequency recalibration with HW timer kernel test robot
@ 2023-01-07 16:01 ` Paul E. McKenney
  2023-01-08  9:14   ` Feng Tang
  0 siblings, 1 reply; 4+ messages in thread
From: Paul E. McKenney @ 2023-01-07 16:01 UTC (permalink / raw)
  To: kernel test robot; +Cc: Feng Tang, oe-kbuild-all

On Sat, Jan 07, 2023 at 05:03:05PM +0800, kernel test robot wrote:
> 
> FYI, we noticed a +64 bytes kernel size regression due to commit:
> 
> commit: 78532abaf5f1c973c99680960ae22bd797951ddf (x86/tsc: Add option to force frequency recalibration with HW timer)
> https://git.kernel.org/cgit/linux/kernel/git/paulmck/linux-rcu.git workqueue.2023.01.06a
> 
> 
> Details as below (size data is obtained by `nm --size-sort vmlinux`):
> 
> 8913f44d: clocksource: Permit limited-duration clocksource watchdogging
> 78532aba: x86/tsc: Add option to force frequency recalibration with HW timer

Perhaps there should be a Kconfig option to disable the clocksource
watchdog?  Not sure that a minimal kernel would worry about such things.

							Thanx, Paul

> +----------------------------------+----------+----------+-------+
> |              symbol              | 8913f44d | 78532aba | delta |
> +----------------------------------+----------+----------+-------+
> | bzImage                          | 495904   | 495968   | 64    |
> | nm.t.tsc_setup                   | 103      | 129      | 26    |
> | nm.t.init_tsc_clocksource        | 111      | 132      | 21    |
> | nm.t.tsc_refine_calibration_work | 427      | 440      | 13    |
> | nm.d.tsc_force_recalibrate       | 0        | 4        | 4     |
> +----------------------------------+----------+----------+-------+
> 
> 
> 
> Thanks
> 

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [lkp] [+64 bytes kernel size regression] [i386-tinyconfig] [78532abaf5] x86/tsc: Add option to force frequency recalibration with HW timer
  2023-01-07 16:01 ` Paul E. McKenney
@ 2023-01-08  9:14   ` Feng Tang
  2023-01-08 17:05     ` Paul E. McKenney
  0 siblings, 1 reply; 4+ messages in thread
From: Feng Tang @ 2023-01-08  9:14 UTC (permalink / raw)
  To: Paul E. McKenney; +Cc: kernel test robot, oe-kbuild-all

On Sat, Jan 07, 2023 at 08:01:32AM -0800, Paul E. McKenney wrote:
> On Sat, Jan 07, 2023 at 05:03:05PM +0800, kernel test robot wrote:
> > 
> > FYI, we noticed a +64 bytes kernel size regression due to commit:
> > 
> > commit: 78532abaf5f1c973c99680960ae22bd797951ddf (x86/tsc: Add option to force frequency recalibration with HW timer)
> > https://git.kernel.org/cgit/linux/kernel/git/paulmck/linux-rcu.git workqueue.2023.01.06a
> > 
> > 
> > Details as below (size data is obtained by `nm --size-sort vmlinux`):
> > 
> > 8913f44d: clocksource: Permit limited-duration clocksource watchdogging
> > 78532aba: x86/tsc: Add option to force frequency recalibration with HW timer
> 
> Perhaps there should be a Kconfig option to disable the clocksource
> watchdog?  Not sure that a minimal kernel would worry about such things.

Yes, there is a CONFIG_CLOCKSOURCE_WATCHDOG option. For 78532aba, IMHO,
64 bytes is a relatively small cost comparing to its potential value.

Thanks,
Feng

> 
> 							Thanx, Paul
> 
> > +----------------------------------+----------+----------+-------+
> > |              symbol              | 8913f44d | 78532aba | delta |
> > +----------------------------------+----------+----------+-------+
> > | bzImage                          | 495904   | 495968   | 64    |
> > | nm.t.tsc_setup                   | 103      | 129      | 26    |
> > | nm.t.init_tsc_clocksource        | 111      | 132      | 21    |
> > | nm.t.tsc_refine_calibration_work | 427      | 440      | 13    |
> > | nm.d.tsc_force_recalibrate       | 0        | 4        | 4     |
> > +----------------------------------+----------+----------+-------+
> > 
> > 
> > 
> > Thanks
> > 

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [lkp] [+64 bytes kernel size regression] [i386-tinyconfig] [78532abaf5] x86/tsc: Add option to force frequency recalibration with HW timer
  2023-01-08  9:14   ` Feng Tang
@ 2023-01-08 17:05     ` Paul E. McKenney
  0 siblings, 0 replies; 4+ messages in thread
From: Paul E. McKenney @ 2023-01-08 17:05 UTC (permalink / raw)
  To: Feng Tang; +Cc: kernel test robot, oe-kbuild-all

On Sun, Jan 08, 2023 at 05:14:30PM +0800, Feng Tang wrote:
> On Sat, Jan 07, 2023 at 08:01:32AM -0800, Paul E. McKenney wrote:
> > On Sat, Jan 07, 2023 at 05:03:05PM +0800, kernel test robot wrote:
> > > 
> > > FYI, we noticed a +64 bytes kernel size regression due to commit:
> > > 
> > > commit: 78532abaf5f1c973c99680960ae22bd797951ddf (x86/tsc: Add option to force frequency recalibration with HW timer)
> > > https://git.kernel.org/cgit/linux/kernel/git/paulmck/linux-rcu.git workqueue.2023.01.06a
> > > 
> > > 
> > > Details as below (size data is obtained by `nm --size-sort vmlinux`):
> > > 
> > > 8913f44d: clocksource: Permit limited-duration clocksource watchdogging
> > > 78532aba: x86/tsc: Add option to force frequency recalibration with HW timer
> > 
> > Perhaps there should be a Kconfig option to disable the clocksource
> > watchdog?  Not sure that a minimal kernel would worry about such things.
> 
> Yes, there is a CONFIG_CLOCKSOURCE_WATCHDOG option. For 78532aba, IMHO,
> 64 bytes is a relatively small cost comparing to its potential value.

Agreed!

It seems to me that the fix here is to make the minimal kernel used for
these stats be built with CONFIG_CLOCKSOURCE_WATCHDOG=n.  Similar to the
way that RCU CPU stall warnings are not enabled in Tiny RCU.

							Thanx, Paul

> Thanks,
> Feng
> 
> > 
> > 							Thanx, Paul
> > 
> > > +----------------------------------+----------+----------+-------+
> > > |              symbol              | 8913f44d | 78532aba | delta |
> > > +----------------------------------+----------+----------+-------+
> > > | bzImage                          | 495904   | 495968   | 64    |
> > > | nm.t.tsc_setup                   | 103      | 129      | 26    |
> > > | nm.t.init_tsc_clocksource        | 111      | 132      | 21    |
> > > | nm.t.tsc_refine_calibration_work | 427      | 440      | 13    |
> > > | nm.d.tsc_force_recalibrate       | 0        | 4        | 4     |
> > > +----------------------------------+----------+----------+-------+
> > > 
> > > 
> > > 
> > > Thanks
> > > 

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2023-01-08 17:05 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2023-01-07  9:03 [lkp] [+64 bytes kernel size regression] [i386-tinyconfig] [78532abaf5] x86/tsc: Add option to force frequency recalibration with HW timer kernel test robot
2023-01-07 16:01 ` Paul E. McKenney
2023-01-08  9:14   ` Feng Tang
2023-01-08 17:05     ` Paul E. McKenney

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.