Re: [PATCH] time: Remove CONFIG_TIMER_STATS

2017-02-08 Thread John Stultz 
On Wed, Feb 8, 2017 at 2:24 AM, Thomas Gleixner  wrote:
> On Tue, 7 Feb 2017, John Stultz wrote:
>> On Tue, Feb 7, 2017 at 3:40 PM, Kees Cook  wrote:
>> > Currently CONFIG_TIMER_STATS exposes process information across namespaces:
>> >
>> > kernel/time/timer_list.c print_timer():
>> >
>> > SEQ_printf(m, ", %s/%d", tmp, timer->start_pid);
>> >
>> > /proc/timer_list:
>> >
>> >  #11: <>, hrtimer_wakeup, S:01, do_nanosleep, cron/2570
>> >
>> > Given that the tracer can give the same information, this patch entirely
>> > removes CONFIG_TIMER_STATS.
>> >
>> > Suggested-by: Thomas Gleixner 
>> > Signed-off-by: Kees Cook 
>>
>> I don't have an issue with this, but I worry this would break some
>> tooling out there. Should it be marked as deprecated first?
>>
>> Or maybe just pulling the band-aid off is the best way?
>
> I think we should just kill it.
>
> No tools can really rely on the behaviour of that file because it depends
> on CONFIG_TIMER_STATS and the information available there is just a random
> snapshot of queued timers at a given point of time, which is in no way
> usefull.

Fair enough.

Acked-by: John Stultz

Re: [PATCH] time: Remove CONFIG_TIMER_STATS

2017-02-08 Thread John Stultz 
On Wed, Feb 8, 2017 at 2:24 AM, Thomas Gleixner  wrote:
> On Tue, 7 Feb 2017, John Stultz wrote:
>> On Tue, Feb 7, 2017 at 3:40 PM, Kees Cook  wrote:
>> > Currently CONFIG_TIMER_STATS exposes process information across namespaces:
>> >
>> > kernel/time/timer_list.c print_timer():
>> >
>> > SEQ_printf(m, ", %s/%d", tmp, timer->start_pid);
>> >
>> > /proc/timer_list:
>> >
>> >  #11: <>, hrtimer_wakeup, S:01, do_nanosleep, cron/2570
>> >
>> > Given that the tracer can give the same information, this patch entirely
>> > removes CONFIG_TIMER_STATS.
>> >
>> > Suggested-by: Thomas Gleixner 
>> > Signed-off-by: Kees Cook 
>>
>> I don't have an issue with this, but I worry this would break some
>> tooling out there. Should it be marked as deprecated first?
>>
>> Or maybe just pulling the band-aid off is the best way?
>
> I think we should just kill it.
>
> No tools can really rely on the behaviour of that file because it depends
> on CONFIG_TIMER_STATS and the information available there is just a random
> snapshot of queued timers at a given point of time, which is in no way
> usefull.

Fair enough.

Acked-by: John Stultz

Re: [PATCH] time: Remove CONFIG_TIMER_STATS

2017-02-08 Thread Thomas Gleixner 
On Tue, 7 Feb 2017, John Stultz wrote:
> On Tue, Feb 7, 2017 at 3:40 PM, Kees Cook  wrote:
> > Currently CONFIG_TIMER_STATS exposes process information across namespaces:
> >
> > kernel/time/timer_list.c print_timer():
> >
> > SEQ_printf(m, ", %s/%d", tmp, timer->start_pid);
> >
> > /proc/timer_list:
> >
> >  #11: <>, hrtimer_wakeup, S:01, do_nanosleep, cron/2570
> >
> > Given that the tracer can give the same information, this patch entirely
> > removes CONFIG_TIMER_STATS.
> >
> > Suggested-by: Thomas Gleixner 
> > Signed-off-by: Kees Cook 
> 
> I don't have an issue with this, but I worry this would break some
> tooling out there. Should it be marked as deprecated first?
> 
> Or maybe just pulling the band-aid off is the best way?

I think we should just kill it.

No tools can really rely on the behaviour of that file because it depends
on CONFIG_TIMER_STATS and the information available there is just a random
snapshot of queued timers at a given point of time, which is in no way
usefull.

Thanks,

tglx

Re: [PATCH] time: Remove CONFIG_TIMER_STATS

2017-02-08 Thread Thomas Gleixner 
On Tue, 7 Feb 2017, John Stultz wrote:
> On Tue, Feb 7, 2017 at 3:40 PM, Kees Cook  wrote:
> > Currently CONFIG_TIMER_STATS exposes process information across namespaces:
> >
> > kernel/time/timer_list.c print_timer():
> >
> > SEQ_printf(m, ", %s/%d", tmp, timer->start_pid);
> >
> > /proc/timer_list:
> >
> >  #11: <>, hrtimer_wakeup, S:01, do_nanosleep, cron/2570
> >
> > Given that the tracer can give the same information, this patch entirely
> > removes CONFIG_TIMER_STATS.
> >
> > Suggested-by: Thomas Gleixner 
> > Signed-off-by: Kees Cook 
> 
> I don't have an issue with this, but I worry this would break some
> tooling out there. Should it be marked as deprecated first?
> 
> Or maybe just pulling the band-aid off is the best way?

I think we should just kill it.

No tools can really rely on the behaviour of that file because it depends
on CONFIG_TIMER_STATS and the information available there is just a random
snapshot of queued timers at a given point of time, which is in no way
usefull.

Thanks,

tglx

Re: [PATCH] time: Remove CONFIG_TIMER_STATS

2017-02-07 Thread kbuild test robot 
Hi Kees,

[auto build test WARNING on tip/timers/core]
[also build test WARNING on v4.10-rc7 next-20170207]
[if your patch is applied to the wrong git tree, please drop us a note to help 
improve the system]

url:
https://github.com/0day-ci/linux/commits/Kees-Cook/time-Remove-CONFIG_TIMER_STATS/20170208-080916
reproduce: make htmldocs

All warnings (new ones prefixed by >>):

   make[3]: warning: jobserver unavailable: using -j1.  Add '+' to parent make 
rule.
   include/linux/init.h:1: warning: no structured comments found
>> include/linux/hrtimer.h:108: warning: Excess struct/union/enum/typedef 
>> member 'start_pid' description in 'hrtimer'
>> include/linux/hrtimer.h:108: warning: Excess struct/union/enum/typedef 
>> member 'start_site' description in 'hrtimer'
>> include/linux/hrtimer.h:108: warning: Excess struct/union/enum/typedef 
>> member 'start_comm' description in 'hrtimer'
   include/linux/kthread.h:26: warning: Excess function parameter '...' 
description in 'kthread_create'
   kernel/sys.c:1: warning: no structured comments found
   drivers/dma-buf/seqno-fence.c:1: warning: no structured comments found
   include/drm/drm_drv.h:409: warning: No description found for parameter 'load'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'firstopen'
   include/drm/drm_drv.h:409: warning: No description found for parameter 'open'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'preclose'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'postclose'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'lastclose'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'unload'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'dma_ioctl'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'dma_quiescent'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'context_dtor'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'set_busid'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'irq_handler'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'irq_preinstall'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'irq_postinstall'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'irq_uninstall'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'debugfs_init'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'debugfs_cleanup'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_open_object'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_close_object'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'prime_handle_to_fd'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'prime_fd_to_handle'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_prime_export'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_prime_import'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_prime_pin'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_prime_unpin'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_prime_res_obj'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_prime_get_sg_table'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_prime_import_sg_table'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_prime_vmap'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_prime_vunmap'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_prime_mmap'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'vgaarb_irq'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_vm_ops'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'major'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'minor'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'patchlevel'
   include/drm/drm_drv.h:409: warning: No description found for parameter 'name'
   include/drm/drm_drv.h:409: warning: No description found for parameter 'desc'
   include/drm/drm_drv.h:409: warning: No description found for parameter 'date'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'driver_features'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'dev_priv_size'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'ioctls'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'num_ioctls'

Re: [PATCH] time: Remove CONFIG_TIMER_STATS

2017-02-07 Thread kbuild test robot 
Hi Kees,

[auto build test WARNING on tip/timers/core]
[also build test WARNING on v4.10-rc7 next-20170207]
[if your patch is applied to the wrong git tree, please drop us a note to help 
improve the system]

url:
https://github.com/0day-ci/linux/commits/Kees-Cook/time-Remove-CONFIG_TIMER_STATS/20170208-080916
reproduce: make htmldocs

All warnings (new ones prefixed by >>):

   make[3]: warning: jobserver unavailable: using -j1.  Add '+' to parent make 
rule.
   include/linux/init.h:1: warning: no structured comments found
>> include/linux/hrtimer.h:108: warning: Excess struct/union/enum/typedef 
>> member 'start_pid' description in 'hrtimer'
>> include/linux/hrtimer.h:108: warning: Excess struct/union/enum/typedef 
>> member 'start_site' description in 'hrtimer'
>> include/linux/hrtimer.h:108: warning: Excess struct/union/enum/typedef 
>> member 'start_comm' description in 'hrtimer'
   include/linux/kthread.h:26: warning: Excess function parameter '...' 
description in 'kthread_create'
   kernel/sys.c:1: warning: no structured comments found
   drivers/dma-buf/seqno-fence.c:1: warning: no structured comments found
   include/drm/drm_drv.h:409: warning: No description found for parameter 'load'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'firstopen'
   include/drm/drm_drv.h:409: warning: No description found for parameter 'open'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'preclose'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'postclose'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'lastclose'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'unload'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'dma_ioctl'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'dma_quiescent'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'context_dtor'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'set_busid'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'irq_handler'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'irq_preinstall'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'irq_postinstall'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'irq_uninstall'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'debugfs_init'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'debugfs_cleanup'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_open_object'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_close_object'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'prime_handle_to_fd'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'prime_fd_to_handle'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_prime_export'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_prime_import'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_prime_pin'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_prime_unpin'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_prime_res_obj'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_prime_get_sg_table'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_prime_import_sg_table'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_prime_vmap'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_prime_vunmap'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_prime_mmap'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'vgaarb_irq'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'gem_vm_ops'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'major'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'minor'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'patchlevel'
   include/drm/drm_drv.h:409: warning: No description found for parameter 'name'
   include/drm/drm_drv.h:409: warning: No description found for parameter 'desc'
   include/drm/drm_drv.h:409: warning: No description found for parameter 'date'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'driver_features'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'dev_priv_size'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'ioctls'
   include/drm/drm_drv.h:409: warning: No description found for parameter 
'num_ioctls'

Re: [PATCH] time: Remove CONFIG_TIMER_STATS

2017-02-07 Thread John Stultz 
On Tue, Feb 7, 2017 at 3:40 PM, Kees Cook  wrote:
> Currently CONFIG_TIMER_STATS exposes process information across namespaces:
>
> kernel/time/timer_list.c print_timer():
>
> SEQ_printf(m, ", %s/%d", tmp, timer->start_pid);
>
> /proc/timer_list:
>
>  #11: <>, hrtimer_wakeup, S:01, do_nanosleep, cron/2570
>
> Given that the tracer can give the same information, this patch entirely
> removes CONFIG_TIMER_STATS.
>
> Suggested-by: Thomas Gleixner 
> Signed-off-by: Kees Cook 

I don't have an issue with this, but I worry this would break some
tooling out there. Should it be marked as deprecated first?

Or maybe just pulling the band-aid off is the best way?

thanks
-john

Re: [PATCH] time: Remove CONFIG_TIMER_STATS

2017-02-07 Thread John Stultz 
On Tue, Feb 7, 2017 at 3:40 PM, Kees Cook  wrote:
> Currently CONFIG_TIMER_STATS exposes process information across namespaces:
>
> kernel/time/timer_list.c print_timer():
>
> SEQ_printf(m, ", %s/%d", tmp, timer->start_pid);
>
> /proc/timer_list:
>
>  #11: <>, hrtimer_wakeup, S:01, do_nanosleep, cron/2570
>
> Given that the tracer can give the same information, this patch entirely
> removes CONFIG_TIMER_STATS.
>
> Suggested-by: Thomas Gleixner 
> Signed-off-by: Kees Cook 

I don't have an issue with this, but I worry this would break some
tooling out there. Should it be marked as deprecated first?

Or maybe just pulling the band-aid off is the best way?

thanks
-john

[PATCH] time: Remove CONFIG_TIMER_STATS

2017-02-07 Thread Kees Cook 
Currently CONFIG_TIMER_STATS exposes process information across namespaces:

kernel/time/timer_list.c print_timer():

SEQ_printf(m, ", %s/%d", tmp, timer->start_pid);

/proc/timer_list:

 #11: <>, hrtimer_wakeup, S:01, do_nanosleep, cron/2570

Given that the tracer can give the same information, this patch entirely
removes CONFIG_TIMER_STATS.

Suggested-by: Thomas Gleixner 
Signed-off-by: Kees Cook 
---
 Documentation/timers/timer_stats.txt |  73 --
 include/linux/hrtimer.h  |   5 -
 include/linux/timer.h|  45 
 kernel/kthread.c |   1 -
 kernel/time/Makefile |   1 -
 kernel/time/hrtimer.c|  38 
 kernel/time/timer.c  |  48 +---
 kernel/time/timer_list.c |  10 -
 kernel/time/timer_stats.c| 425 ---
 kernel/workqueue.c   |   2 -
 lib/Kconfig.debug|  14 --
 11 files changed, 2 insertions(+), 660 deletions(-)
 delete mode 100644 Documentation/timers/timer_stats.txt
 delete mode 100644 kernel/time/timer_stats.c

diff --git a/Documentation/timers/timer_stats.txt 
b/Documentation/timers/timer_stats.txt
deleted file mode 100644
index de835ee97455..
--- a/Documentation/timers/timer_stats.txt
+++ /dev/null
@@ -1,73 +0,0 @@
-timer_stats - timer usage statistics
-
-
-timer_stats is a debugging facility to make the timer (ab)usage in a Linux
-system visible to kernel and userspace developers. If enabled in the config
-but not used it has almost zero runtime overhead, and a relatively small
-data structure overhead. Even if collection is enabled runtime all the
-locking is per-CPU and lookup is hashed.
-
-timer_stats should be used by kernel and userspace developers to verify that
-their code does not make unduly use of timers. This helps to avoid unnecessary
-wakeups, which should be avoided to optimize power consumption.
-
-It can be enabled by CONFIG_TIMER_STATS in the "Kernel hacking" configuration
-section.
-
-timer_stats collects information about the timer events which are fired in a
-Linux system over a sample period:
-
-- the pid of the task(process) which initialized the timer
-- the name of the process which initialized the timer
-- the function where the timer was initialized
-- the callback function which is associated to the timer
-- the number of events (callbacks)
-
-timer_stats adds an entry to /proc: /proc/timer_stats
-
-This entry is used to control the statistics functionality and to read out the
-sampled information.
-
-The timer_stats functionality is inactive on bootup.
-
-To activate a sample period issue:
-# echo 1 >/proc/timer_stats
-
-To stop a sample period issue:
-# echo 0 >/proc/timer_stats
-
-The statistics can be retrieved by:
-# cat /proc/timer_stats
-
-While sampling is enabled, each readout from /proc/timer_stats will see
-newly updated statistics. Once sampling is disabled, the sampled information
-is kept until a new sample period is started. This allows multiple readouts.
-
-Sample output of /proc/timer_stats:
-
-Timerstats sample period: 3.888770 s
-  12, 0 swapper  hrtimer_stop_sched_tick (hrtimer_sched_tick)
-  15, 1 swapper  hcd_submit_urb (rh_timer_func)
-   4,   959 kedacschedule_timeout (process_timeout)
-   1, 0 swapper  page_writeback_init (wb_timer_fn)
-  28, 0 swapper  hrtimer_stop_sched_tick (hrtimer_sched_tick)
-  22,  2948 IRQ 4tty_flip_buffer_push (delayed_work_timer_fn)
-   3,  3100 bash schedule_timeout (process_timeout)
-   1, 1 swapper  queue_delayed_work_on (delayed_work_timer_fn)
-   1, 1 swapper  queue_delayed_work_on (delayed_work_timer_fn)
-   1, 1 swapper  neigh_table_init_no_netlink (neigh_periodic_timer)
-   1,  2292 ip   __netdev_watchdog_up (dev_watchdog)
-   1,23 events/1 do_cache_clean (delayed_work_timer_fn)
-90 total events, 30.0 events/sec
-
-The first column is the number of events, the second column the pid, the third
-column is the name of the process. The forth column shows the function which
-initialized the timer and in parenthesis the callback function which was
-executed on expiry.
-
-Thomas, Ingo
-
-Added flag to indicate 'deferrable timer' in /proc/timer_stats. A deferrable
-timer will appear as follows
-  10D, 1 swapper  queue_delayed_work_on (delayed_work_timer_fn)
-
diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index cdab81ba29f8..19c66b89899c 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -104,11 +104,6 @@ struct hrtimer {
struct hrtimer_clock_base   *base;
u8  state;
u8  is_rel;
-#ifdef CONFIG_TIMER_STATS
-   int

[PATCH] time: Remove CONFIG_TIMER_STATS

2017-02-07 Thread Kees Cook 
Currently CONFIG_TIMER_STATS exposes process information across namespaces:

kernel/time/timer_list.c print_timer():

SEQ_printf(m, ", %s/%d", tmp, timer->start_pid);

/proc/timer_list:

 #11: <>, hrtimer_wakeup, S:01, do_nanosleep, cron/2570

Given that the tracer can give the same information, this patch entirely
removes CONFIG_TIMER_STATS.

Suggested-by: Thomas Gleixner 
Signed-off-by: Kees Cook 
---
 Documentation/timers/timer_stats.txt |  73 --
 include/linux/hrtimer.h  |   5 -
 include/linux/timer.h|  45 
 kernel/kthread.c |   1 -
 kernel/time/Makefile |   1 -
 kernel/time/hrtimer.c|  38 
 kernel/time/timer.c  |  48 +---
 kernel/time/timer_list.c |  10 -
 kernel/time/timer_stats.c| 425 ---
 kernel/workqueue.c   |   2 -
 lib/Kconfig.debug|  14 --
 11 files changed, 2 insertions(+), 660 deletions(-)
 delete mode 100644 Documentation/timers/timer_stats.txt
 delete mode 100644 kernel/time/timer_stats.c

diff --git a/Documentation/timers/timer_stats.txt 
b/Documentation/timers/timer_stats.txt
deleted file mode 100644
index de835ee97455..
--- a/Documentation/timers/timer_stats.txt
+++ /dev/null
@@ -1,73 +0,0 @@
-timer_stats - timer usage statistics
-
-
-timer_stats is a debugging facility to make the timer (ab)usage in a Linux
-system visible to kernel and userspace developers. If enabled in the config
-but not used it has almost zero runtime overhead, and a relatively small
-data structure overhead. Even if collection is enabled runtime all the
-locking is per-CPU and lookup is hashed.
-
-timer_stats should be used by kernel and userspace developers to verify that
-their code does not make unduly use of timers. This helps to avoid unnecessary
-wakeups, which should be avoided to optimize power consumption.
-
-It can be enabled by CONFIG_TIMER_STATS in the "Kernel hacking" configuration
-section.
-
-timer_stats collects information about the timer events which are fired in a
-Linux system over a sample period:
-
-- the pid of the task(process) which initialized the timer
-- the name of the process which initialized the timer
-- the function where the timer was initialized
-- the callback function which is associated to the timer
-- the number of events (callbacks)
-
-timer_stats adds an entry to /proc: /proc/timer_stats
-
-This entry is used to control the statistics functionality and to read out the
-sampled information.
-
-The timer_stats functionality is inactive on bootup.
-
-To activate a sample period issue:
-# echo 1 >/proc/timer_stats
-
-To stop a sample period issue:
-# echo 0 >/proc/timer_stats
-
-The statistics can be retrieved by:
-# cat /proc/timer_stats
-
-While sampling is enabled, each readout from /proc/timer_stats will see
-newly updated statistics. Once sampling is disabled, the sampled information
-is kept until a new sample period is started. This allows multiple readouts.
-
-Sample output of /proc/timer_stats:
-
-Timerstats sample period: 3.888770 s
-  12, 0 swapper  hrtimer_stop_sched_tick (hrtimer_sched_tick)
-  15, 1 swapper  hcd_submit_urb (rh_timer_func)
-   4,   959 kedacschedule_timeout (process_timeout)
-   1, 0 swapper  page_writeback_init (wb_timer_fn)
-  28, 0 swapper  hrtimer_stop_sched_tick (hrtimer_sched_tick)
-  22,  2948 IRQ 4tty_flip_buffer_push (delayed_work_timer_fn)
-   3,  3100 bash schedule_timeout (process_timeout)
-   1, 1 swapper  queue_delayed_work_on (delayed_work_timer_fn)
-   1, 1 swapper  queue_delayed_work_on (delayed_work_timer_fn)
-   1, 1 swapper  neigh_table_init_no_netlink (neigh_periodic_timer)
-   1,  2292 ip   __netdev_watchdog_up (dev_watchdog)
-   1,23 events/1 do_cache_clean (delayed_work_timer_fn)
-90 total events, 30.0 events/sec
-
-The first column is the number of events, the second column the pid, the third
-column is the name of the process. The forth column shows the function which
-initialized the timer and in parenthesis the callback function which was
-executed on expiry.
-
-Thomas, Ingo
-
-Added flag to indicate 'deferrable timer' in /proc/timer_stats. A deferrable
-timer will appear as follows
-  10D, 1 swapper  queue_delayed_work_on (delayed_work_timer_fn)
-
diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index cdab81ba29f8..19c66b89899c 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -104,11 +104,6 @@ struct hrtimer {
struct hrtimer_clock_base   *base;
u8  state;
u8  is_rel;
-#ifdef CONFIG_TIMER_STATS
-   int start_pid;
-   void