25 Nov, 2008
1 commit
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Impact: cleanup, move all hrtimer processing into hardirq context
This is an attempt at removing some of the hrtimer complexity by
reducing the number of callback modes to 1.This means that all hrtimer callback functions will be ran from HARD-irq
context.I went through all the 30 odd hrtimer callback functions in the kernel
and saw only one that I'm not quite sure of, which is the one in
net/can/bcm.c - hence I'm CC-ing the folks responsible for that code.Furthermore, the hrtimer core now calls callbacks directly with IRQs
disabled in case you try to enqueue an expired timer. If this timer is a
periodic timer (which should use hrtimer_forward() to advance its time)
then it might be possible to end up in an inf. recursive loop due to the
fact that hrtimer_forward() doesn't round up to the next timer
granularity, and therefore keeps on calling the callback - obviously
this needs a fix.Aside from that, this seems to compile and actually boot on my dual core
test box - although I'm sure there are some bugs in, me not hitting any
makes me certain :-)Signed-off-by: Peter Zijlstra
Signed-off-by: Ingo Molnar
12 Nov, 2008
1 commit
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Impact: cleanup
git grep HRTIMER_CB_IRQSAFE revealed half the callback modes are actually
unused.Signed-off-by: Peter Zijlstra
Signed-off-by: Ingo Molnar
07 Nov, 2008
1 commit
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Fix the hrtimer_add_expires_ns() function. It should take a 'u64 ns' argument,
but rather takes an 'unsigned long ns' argument - which might only be 32-bits.On FRV, this results in the kernel locking up because hrtimer_forward() passes
the result of a 64-bit multiplication to this function, for which the compiler
discards the top 32-bits - something that didn't happen when ktime_add_ns() was
called directly.Signed-off-by: David Howells
Acked-by: Arjan van de Ven
Signed-off-by: Linus Torvalds
22 Oct, 2008
1 commit
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Conflicts:
kernel/time/tick-sched.c
Signed-off-by: Thomas Gleixner
20 Oct, 2008
2 commits
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Signed-off-by: Thomas Gleixner
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…tp', 'timers/posixtimers' and 'timers/debug' into v28-timers-for-linus
18 Oct, 2008
1 commit
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Conflicts:
arch/x86/kvm/i8254.c
15 Oct, 2008
1 commit
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Signed-off-by: Stephen Rothwell
08 Oct, 2008
1 commit
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the timer peek function was on the wrong side of an ifdef,
breaking for the !HRTIMERs case. Just provide an empty inline
for that case since it doesn't make sense in that scenario.Signed-off-by: Arjan van de Ven
29 Sep, 2008
2 commits
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Impact: per CPU hrtimers can be migrated from a dead CPU
The hrtimer code has no knowledge about per CPU timers, but we need to
prevent the migration of such timers and warn when such a timer is
active at migration time.Explicitely mark the timers as per CPU and use a more understandable
mode descriptor for the interrupts safe unlocked callback mode, which
is used by hrtimer_sleeper and the scheduler code.Signed-off-by: Thomas Gleixner
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Impact: during migration active hrtimers can be seen as inactive
The migration code removes the hrtimers from the queues of the dead
CPU and sets the state temporary to INACTIVE. The enqueue code sets it
to ACTIVE/PENDING again.Prevent that the wrong state can be seen by using a separate migration
state bit.Signed-off-by: Thomas Gleixner
24 Sep, 2008
1 commit
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reorder struct hrtimer to save 8 bytes on 64 bit builds when
CONFIG_TIMER_STATS selected. (also removes 8 bytes from signal_struct)Signed-off-by: Richard Kennedy
Signed-off-by: Andrew Morton
Signed-off-by: Thomas Gleixner
22 Sep, 2008
2 commits
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hrtimer_clock_base::reprogram() also appears to never
have been used, so remove it.Signed-off-by: Mark McLoughlin
Signed-off-by: Ingo Molnar -
Peter Zijlstra noticed this 8 months ago and I just noticed
it again.hrtimer_clock_base::get_softirq_time() is currently unused
in the entire tree. In fact, looking at the logs, it appears
as if it was never used. Remove it.Signed-off-by: Mark McLoughlin
Signed-off-by: Ingo Molnar
11 Sep, 2008
1 commit
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As part of going idle, we already look at the time of the next timer event to determine
which C-state to select etc.This patch adds functionality that causes the timers that are past their
soft expire time, to fire at this time, before we calculate the next wakeup
time. This functionality will thus avoid wakeups by running timers before
going idle rather than specially waking up for it.Signed-off-by: Arjan van de Ven
08 Sep, 2008
2 commits
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(based on lkml review)
* use rt_task()
* task_nice() has a signSigned-off-by: Arjan van de Ven
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this patch adds a _range version of hrtimer_start() so that range timers
can be created; the hrtimer_start() function is just a wrapper around this.In addition, hrtimer_start_expires() will now preserve existing ranges.
Signed-off-by: Arjan van de Ven
07 Sep, 2008
1 commit
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More randconfig testing
Signed-off-by: Arjan van de Ven
06 Sep, 2008
5 commits
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in some randconfig configurations, hrtimers are used even though
the hrtimer config if off; and it broke the build due to some of
the new functions being on the wrong side of the ifdef.This patch moves the functions to the other side of the ifdef, fixing
the build bug.Signed-off-by: Arjan van de Ven
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this patch turns hrtimers into range timers; they have 2 expire points
1) the soft expire point
2) the hard expire pointthe kernel will do it's regular best effort attempt to get the timer run
at the hard expire point. However, if some other time fires after the soft
expire point, the kernel now has the freedom to fire this timer at this point,
and thus grouping the events and preventing a power-expensive wakeup in the
future.Signed-off-by: Arjan van de Ven
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To catch code that still touches the "expires" memory directly, rename it
to have the compiler complain rather than get nasty, hard to explain,
runtime behaviorSigned-off-by: Arjan van de Ven
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In order to be able to turn hrtimers into range based, we need to provide
accessor functions for getting to the "expires" ktime_t member of the
struct hrtimer.This patch adds a set of accessors for this purpose:
* hrtimer_set_expires
* hrtimer_set_expires_tv64
* hrtimer_add_expires
* hrtimer_add_expires_ns
* hrtimer_get_expires
* hrtimer_get_expires_tv64
* hrtimer_get_expires_ns
* hrtimer_expires_remaining
* hrtimer_start_expiresNo users of these new accessors are added yet; these follow in later patches.
Hopefully this patch can even go into 2.6.27-rc so that the conversions will
not have a bottleneck in -nextSigned-off-by: Arjan van de Ven
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This patch adds a schedule_hrtimeout() function, to be used by select() and
poll() in a later patch. This function works similar to schedule_timeout()
in most ways, but takes a timespec rather than jiffies.With a lot of contributions/fixes from Thomas
Signed-off-by: Arjan van de Ven
Signed-off-by: Thomas Gleixner
04 May, 2008
1 commit
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The helper function hrtimer_callback_running() is used in
kernel/hrtimer.c as well as in the updated net/can/bcm.c which now
supports hrtimers. Moving the helper function to hrtimer.h removes the
duplicate definition in the C-files.Signed-off-by: Oliver Hartkopp
Cc: David Miller
Signed-off-by: Thomas Gleixner
30 Apr, 2008
1 commit
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hrtimers have now dynamic users in the network code. Put them under
debugobjects surveillance as well.Add calls to the generic object debugging infrastructure and provide fixup
functions which allow to keep the system alive when recoverable problems have
been detected by the object debugging core code.Signed-off-by: Thomas Gleixner
Cc: Greg KH
Cc: Randy Dunlap
Cc: Kay Sievers
Cc: Ingo Molnar
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
17 Apr, 2008
1 commit
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In order to avoid the false positive from lockdep, each per-cpu base->lock has
the separate lock class and migrate_hrtimers() uses double_spin_lock().This is overcomplicated: except for migrate_hrtimers() we never take 2 locks
at once, and migrate_hrtimers() can use spin_lock_nested().Signed-off-by: Oleg Nesterov
Cc: Arjan van de Ven
Cc: Heiko Carstens
Cc: Ingo Molnar
Cc: Peter Zijlstra
Signed-off-by: Andrew Morton
Signed-off-by: Thomas Gleixner
10 Feb, 2008
1 commit
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Spotted by Pavel Emelyanov and Alexey Dobriyan.
hrtimer_nanosleep() sets restart_block->arg1 = rmtp, but this rmtp points to
the local variable which lives in the caller's stack frame. This means that
if sys_restart_syscall() actually happens and it is interrupted as well, we
don't update the user-space variable, but write into the already dead stack
frame.Introduced by commit 04c227140fed77587432667a574b14736a06dd7f
hrtimer: Rework hrtimer_nanosleep to make sys_compat_nanosleep easierChange the callers to pass "__user *rmtp" to hrtimer_nanosleep(), and change
hrtimer_nanosleep() to use copy_to_user() to actually update *rmtp.Small problem remains. man 2 nanosleep states that *rtmp should be written if
nanosleep() was interrupted (it says nothing whether it is OK to update *rmtp
if nanosleep returns 0), but (with or without this patch) we can dirty *rem
even if nanosleep() returns 0.NOTE: this patch doesn't change compat_sys_nanosleep(), because it has other
bugs. Fixed by the next patch.Signed-off-by: Oleg Nesterov
Cc: Alexey Dobriyan
Cc: Michael Kerrisk
Cc: Pavel Emelyanov
Cc: Peter Zijlstra
Cc: Toyo Abe
Cc: Andrew Morton
Signed-off-by: Thomas Gleixnerinclude/linux/hrtimer.h | 2 -
kernel/hrtimer.c | 51 +++++++++++++++++++++++++-----------------------
kernel/posix-timers.c | 14 +------------
3 files changed, 30 insertions(+), 37 deletions(-)
09 Feb, 2008
1 commit
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Fix typo in comments.
BTW: I have to fix coding style in arch/ia64/kernel/time.c also, otherwise
checkpatch.pl will be complaining.Signed-off-by: Li Zefan
Cc: Thomas Gleixner
Cc: Ingo Molnar
Cc: john stultz
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
08 Feb, 2008
1 commit
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Commit ad7f71674ad7c3c4467e48f6ab9e85516dae2720 ("[POWERPC] Use a
sensible default for clock_getres() in the VDSO") corrected the clock
resolution reported by the VDSO clock_getres() but introduced another
problem in that older versions of gcc (gcc-4.0 and earlier) fail to
compile the new code in arch/powerpc/kernel/asm-offsets.c.This fixes it by introducing a new MONOTONIC_RES_NSEC define in the
generic code which is equivalent to KTIME_MONOTONIC_RES but is just an
integer constant, not a ktime union.Signed-off-by: Tony Breeds
Signed-off-by: Paul Mackerras
Signed-off-by: Linus Torvalds
06 Feb, 2008
2 commits
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This is the new timerfd API as it is implemented by the following patch:
int timerfd_create(int clockid, int flags);
int timerfd_settime(int ufd, int flags,
const struct itimerspec *utmr,
struct itimerspec *otmr);
int timerfd_gettime(int ufd, struct itimerspec *otmr);The timerfd_create() API creates an un-programmed timerfd fd. The "clockid"
parameter can be either CLOCK_MONOTONIC or CLOCK_REALTIME.The timerfd_settime() API give new settings by the timerfd fd, by optionally
retrieving the previous expiration time (in case the "otmr" parameter is not
NULL).The time value specified in "utmr" is absolute, if the TFD_TIMER_ABSTIME bit
is set in the "flags" parameter. Otherwise it's a relative time.The timerfd_gettime() API returns the next expiration time of the timer, or
{0, 0} if the timerfd has not been set yet.Like the previous timerfd API implementation, read(2) and poll(2) are
supported (with the same interface). Here's a simple test program I used to
exercise the new timerfd APIs:http://www.xmailserver.org/timerfd-test2.c
[akpm@linux-foundation.org: coding-style cleanups]
[akpm@linux-foundation.org: fix ia64 build]
[akpm@linux-foundation.org: fix m68k build]
[akpm@linux-foundation.org: fix mips build]
[akpm@linux-foundation.org: fix alpha, arm, blackfin, cris, m68k, s390, sparc and sparc64 builds]
[heiko.carstens@de.ibm.com: fix s390]
[akpm@linux-foundation.org: fix powerpc build]
[akpm@linux-foundation.org: fix sparc64 more]
Signed-off-by: Davide Libenzi
Cc: Michael Kerrisk
Cc: Thomas Gleixner
Cc: Davide Libenzi
Cc: Michael Kerrisk
Cc: Martin Schwidefsky
Signed-off-by: Heiko Carstens
Cc: Michael Kerrisk
Cc: Davide Libenzi
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
I think that advancing the timer against the timer's current "now" can be a
pretty common usage, so, w/out exposing hrtimer's internals, we add a new
hrtimer_forward_now() function.Signed-off-by: Davide Libenzi
Cc: Michael Kerrisk
Cc: Thomas Gleixner
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
03 Feb, 2008
1 commit
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Function do_timer_interrupt_hook() don't take argument regs,
and structure hrtimer_sleeper don't have member cb_pending.
So delete comments refering to these symbols.Signed-off-by: Li Zefan
Signed-off-by: Adrian Bunk
26 Jan, 2008
2 commits
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Currently all highres=off timers are run from softirq context, but
HRTIMER_CB_IRQSAFE_NO_SOFTIRQ timers expect to run from irq context.Fix this up by splitting it similar to the highres=on case.
Signed-off-by: Peter Zijlstra
Signed-off-by: Ingo Molnar -
Use HR-timers (when available) to deliver an accurate preemption tick.
The regular scheduler tick that runs at 1/HZ can be too coarse when nice
level are used. The fairness system will still keep the cpu utilisation 'fair'
by then delaying the task that got an excessive amount of CPU time but try to
minimize this by delivering preemption points spot-on.The average frequency of this extra interrupt is sched_latency / nr_latency.
Which need not be higher than 1/HZ, its just that the distribution within the
sched_latency period is important.Signed-off-by: Peter Zijlstra
Signed-off-by: Ingo Molnar
19 Oct, 2007
1 commit
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Pull the copy_to_user out of hrtimer_nanosleep and into the callers
(common_nsleep, sys_nanosleep) in preparation for converting
compat_sys_nanosleep to use hrtimers.Signed-off-by: Anton Blanchard
Acked-by: Arnd Bergmann
Signed-off-by: Thomas Gleixner
17 Jul, 2007
1 commit
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Add a flag in /proc/timer_stats to indicate deferrable timers. This will
let developers/users to differentiate between types of tiemrs in
/proc/timer_stats.Deferrable timer and normal timer will appear in /proc/timer_stats as below.
10D, 1 swapper queue_delayed_work_on (delayed_work_timer_fn)
10, 1 swapper queue_delayed_work_on (delayed_work_timer_fn)Also version of timer_stats changes from v0.1 to v0.2
Signed-off-by: Venkatesh Pallipadi
Acked-by: Ingo Molnar
Cc: Thomas Gleixner
Cc: john stultz
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
08 Apr, 2007
1 commit
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Soeren Sonnenburg reported that upon resume he is getting
this backtrace:[] smp_apic_timer_interrupt+0x57/0x90
[] retrigger_next_event+0x0/0xb0
[] apic_timer_interrupt+0x28/0x30
[] retrigger_next_event+0x0/0xb0
[] __kfifo_put+0x8/0x90
[] on_each_cpu+0x35/0x60
[] clock_was_set+0x18/0x20
[] timekeeping_resume+0x7c/0xa0
[] __sysdev_resume+0x11/0x80
[] sysdev_resume+0x47/0x80
[] device_power_up+0x5/0x10it turns out that on resume we mistakenly re-enable interrupts too
early. Do the timer retrigger only on the current CPU.Signed-off-by: Ingo Molnar
Acked-by: Thomas Gleixner
Acked-by: Soeren Sonnenburg
Signed-off-by: Linus Torvalds
07 Mar, 2007
2 commits
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The description for the hrtimer_clock_base struct describes "hrtimer_base".
That should be hrtimer_clock_base.Signed-off-by: Andres Salomon
Acked-by: Thomas Gleixner
Acked-by: Ingo Molnar
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The description for HRTIMER_CB_IRQSAFE_NO_SOFTIRQ is backwards; "NO
SOFTIRQ" sounds a whole lot like it means it must not be run in a softirq.Signed-off-by: Andres Salomon
Acked-by: Thomas Gleixner
Acked-by: Ingo Molnar
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
02 Mar, 2007
1 commit
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Fix kernel-doc warnings in 2.6.20-git15 (lib/, mm/, kernel/, include/).
Signed-off-by: Randy Dunlap
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
