- 27 1月, 2012 8 次提交
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由 John Stultz 提交于
Now that ntp.c's locking is reworked, we can remove most of the xtime_lock usage in timekeeping.c The remaining xtime_lock presence is really for jiffies access and the global load calculation. CC: Thomas Gleixner <tglx@linutronix.de> CC: Eric Dumazet <eric.dumazet@gmail.com> CC: Richard Cochran <richardcochran@gmail.com> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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由 John Stultz 提交于
Currently the NTP managed tick_length value is accessed globally, in preparations for locking cleanups, make sure it is accessed via a function and mark it as static. CC: Thomas Gleixner <tglx@linutronix.de> CC: Eric Dumazet <eric.dumazet@gmail.com> CC: Richard Cochran <richardcochran@gmail.com> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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由 John Stultz 提交于
Now that all the timekeeping variables are stored in the timekeeper structure, add a new lock to protect the structure. For now, this lock nests under the xtime_lock for writes. For readers, we don't need to take xtime_lock anymore. CC: Thomas Gleixner <tglx@linutronix.de> CC: Eric Dumazet <eric.dumazet@gmail.com> CC: Richard Cochran <richardcochran@gmail.com> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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由 John Stultz 提交于
Move global xtime_lock and timekeeping_suspended values up to the top of timekeeping.c CC: Thomas Gleixner <tglx@linutronix.de> CC: Eric Dumazet <eric.dumazet@gmail.com> CC: Richard Cochran <richardcochran@gmail.com> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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由 John Stultz 提交于
In preparation for locking cleanups, move raw_time into timekeeper structure. CC: Thomas Gleixner <tglx@linutronix.de> CC: Eric Dumazet <eric.dumazet@gmail.com> CC: Richard Cochran <richardcochran@gmail.com> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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由 John Stultz 提交于
In preparation for locking cleanups, move xtime into timekeeper structure. CC: Thomas Gleixner <tglx@linutronix.de> CC: Eric Dumazet <eric.dumazet@gmail.com> CC: Richard Cochran <richardcochran@gmail.com> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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由 John Stultz 提交于
In preparation for locking cleanups, move wall_to_monotonic into the timekeeper structure. CC: Thomas Gleixner <tglx@linutronix.de> CC: Eric Dumazet <eric.dumazet@gmail.com> CC: Richard Cochran <richardcochran@gmail.com> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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由 John Stultz 提交于
Move total_sleep_time into the timekeeper structure in preparation for locking cleanups CC: Thomas Gleixner <tglx@linutronix.de> CC: Eric Dumazet <eric.dumazet@gmail.com> CC: Richard Cochran <richardcochran@gmail.com> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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- 22 11月, 2011 2 次提交
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由 John Stultz 提交于
Fixup spelling issues caught by Richard CC: Richard Cochran <richardcochran@gmail.com> CC: Chen Jie <chenj@lemote.com> CC: Steven Rostedt <rostedt@goodmis.org> CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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由 Dan McGee 提交于
The whole point of this function is to return a value not touched by NTP; unfortunately the comment got copied wholesale without adjustment from the timekeeping_get_ns function above. Signed-off-by: NDan McGee <dpmcgee@gmail.com> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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- 18 11月, 2011 1 次提交
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由 Hector Palacios 提交于
ktime_get and ktime_get_ts were calling timekeeping_get_ns() but later they were not calling arch_gettimeoffset() so architectures using this mechanism returned 0 ns when calling these functions. This happened for example when running Busybox's ping which calls syscall(__NR_clock_gettime, CLOCK_MONOTONIC, ts) which eventually calls ktime_get. As a result the returned ping travel time was zero. CC: stable@kernel.org Signed-off-by: NHector Palacios <hector.palacios@digi.com> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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- 11 11月, 2011 1 次提交
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由 John Stultz 提交于
For some frequencies, the clocks_calc_mult_shift() function will unfortunately select mult values very close to 0xffffffff. This has the potential to overflow when NTP adjusts the clock, adding to the mult value. This patch adds a clocksource.maxadj value, which provides an approximation of an 11% adjustment(NTP limits adjustments to 500ppm and the tick adjustment is limited to 10%), which could be made to the clocksource.mult value. This is then used to both check that the current mult value won't overflow/underflow, as well as warning us if the timekeeping_adjust() code pushes over that 11% boundary. v2: Fix max_adjustment calculation, and improve WARN_ONCE messages. v3: Don't warn before maxadj has actually been set CC: Yong Zhang <yong.zhang0@gmail.com> CC: David Daney <ddaney.cavm@gmail.com> CC: Thomas Gleixner <tglx@linutronix.de> CC: Chen Jie <chenj@lemote.com> CC: zhangfx <zhangfx@lemote.com> CC: stable@kernel.org Reported-by: NChen Jie <chenj@lemote.com> Reported-by: Nzhangfx <zhangfx@lemote.com> Tested-by: NYong Zhang <yong.zhang0@gmail.com> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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- 28 10月, 2011 1 次提交
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由 John Stultz 提交于
After getting a number of questions in private emails about the math around admittedly very complex timekeeping_adjust() and timekeeping_big_adjust(), I figure the code needs some better comments. Hopefully the explanations are clear enough and don't muddy the water any worse. Still needs documentation for ntp_error, but I couldn't recall exactly the full explanation behind the code that's there (although I do recall once working it out when Roman first proposed it). Given a bit more time I can probably work it out, but I don't want to hold back this documentation until then. Signed-off-by: NJohn Stultz <john.stultz@linaro.org> Cc: Chen Jie <chenj@lemote.com> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1319764362-32367-1-git-send-email-john.stultz@linaro.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>
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- 21 7月, 2011 1 次提交
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由 John Stultz 提交于
Terribly embarassing. Don't know how I committed this, but its KERN_WARNING not KERN_WARN. This fixes the following compile error: kernel/time/timekeeping.c: In function ‘__timekeeping_inject_sleeptime’: kernel/time/timekeeping.c:608: error: ‘KERN_WARN’ undeclared (first use in this function) kernel/time/timekeeping.c:608: error: (Each undeclared identifier is reported only once kernel/time/timekeeping.c:608: error: for each function it appears in.) kernel/time/timekeeping.c:608: error: expected ‘)’ before string constant make[2]: *** [kernel/time/timekeeping.o] Error 1 Reported-by: NIngo Molnar <mingo@elte.hu> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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- 22 6月, 2011 2 次提交
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由 John Stultz 提交于
Because the read_persistent_clock interface is usually backed by only a second granular interface, each time we read from the persistent clock for suspend/resume, we introduce a half second (on average) of error. In order to avoid this error accumulating as the system is suspended over and over, this patch measures the time delta between the persistent clock and the system CLOCK_REALTIME. If the delta is less then 2 seconds from the last suspend, we compensate by using the previous time delta (keeping it close). If it is larger then 2 seconds, we assume the clock was set or has been changed, so we do no correction and update the delta. Note: If NTP is running, ths could seem to "fight" with the NTP corrected time, where as if the system time was off by 1 second, and NTP slewed the value in, a suspend/resume cycle could undo this correction, by trying to restore the previous offset from the persistent clock. However, without this patch, since each read could cause almost a full second worth of error, its possible to get almost 2 seconds of error just from the suspend/resume cycle alone, so this about equal to any offset added by the compensation. Further on systems that suspend/resume frequently, this should keep time closer then NTP could compensate for if the errors were allowed to accumulate. Credits to Arve Hjønnevåg for suggesting this solution. CC: Arve Hjønnevåg <arve@android.com> CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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由 John Stultz 提交于
Arve suggested making sure we catch possible negative sleep time intervals that could be passed into timekeeping_inject_sleeptime. CC: Arve Hjønnevåg <arve@android.com> CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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- 03 5月, 2011 2 次提交
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由 Thomas Gleixner 提交于
Some applications must be aware of clock realtime being set backward. A simple example is a clock applet which arms a timer for the next minute display. If clock realtime is set backward then the applet displays a stale time for the amount of time which the clock was set backwards. Due to that applications poll the time because we don't have an interface. Extend the timerfd interface by adding a flag which puts the timer onto a different internal realtime clock. All timers on this clock are expired whenever the clock was set. The timerfd core records the monotonic offset when the timer is created. When the timer is armed, then the current offset is compared to the previous recorded offset. When it has changed, then timerfd_settime returns -ECANCELED. When a timer is read the offset is compared and if it changed -ECANCELED returned to user space. Periodic timers are not rearmed in the cancelation case. Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Acked-by: NJohn Stultz <johnstul@us.ibm.com> Cc: Chris Friesen <chris.friesen@genband.com> Tested-by: NKay Sievers <kay.sievers@vrfy.org> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Davide Libenzi <davidel@xmailserver.org> Reviewed-by: NAlexander Shishkin <virtuoso@slind.org> Link: http://lkml.kernel.org/r/%3Calpine.LFD.2.02.1104271359580.3323%40ionos%3ESigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 Thomas Gleixner 提交于
Make clock_was_set() unconditional and rename hres_timers_resume to hrtimers_resume. This is a preparatory patch for hrtimers which are cancelled when clock realtime was set. Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 27 4月, 2011 1 次提交
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由 John Stultz 提交于
Some platforms cannot implement read_persistent_clock, as their RTC devices are only accessible when interrupts are enabled. This keeps them from being used by the timekeeping code on resume to measure the time in suspend. The RTC layer tries to work around this, by calling do_settimeofday on resume after irqs are reenabled to set the time properly. However, this only corrects CLOCK_REALTIME, and does not properly adjust the sleep time value. This causes btime in /proc/stat to be incorrect as well as making the new CLOCK_BOTTTIME inaccurate. This patch resolves the issue by introducing a new timekeeping hook to allow the RTC layer to inject the sleep time on resume. The code also checks to make sure that read_persistent_clock is nonfunctional before setting the sleep time, so that should the RTC's HCTOSYS option be configured in on a system that does support read_persistent_clock we will not increase the total_sleep_time twice. CC: Arve Hjønnevåg <arve@android.com> CC: Thomas Gleixner <tglx@linutronix.de> Acked-by: NArnd Bergmann <arnd@arndb.de> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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- 24 3月, 2011 1 次提交
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由 Rafael J. Wysocki 提交于
The timekeeping subsystem uses a sysdev class and a sysdev for executing timekeeping_suspend() after interrupts have been turned off on the boot CPU (during system suspend) and for executing timekeeping_resume() before turning on interrupts on the boot CPU (during system resume). However, since both of these functions ignore their arguments, the entire mechanism may be replaced with a struct syscore_ops object which is simpler. Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl> Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
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- 22 2月, 2011 2 次提交
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由 John Stultz 提交于
Extend get_xtime_and_monotonic_offset to get_xtime_and_monotonic_and_sleep_offset(). CC: Jamie Lokier <jamie@shareable.org> CC: Thomas Gleixner <tglx@linutronix.de> CC: Alexander Shishkin <virtuoso@slind.org> CC: Arve Hjønnevåg <arve@android.com> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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由 John Stultz 提交于
This adds new functions that return the monotonic time since boot (in other words, CLOCK_MONOTONIC + suspend time). CC: Jamie Lokier <jamie@shareable.org> CC: Thomas Gleixner <tglx@linutronix.de> CC: Alexander Shishkin <virtuoso@slind.org> CC: Arve Hjønnevåg <arve@android.com> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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- 02 2月, 2011 2 次提交
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由 John Stultz 提交于
This adds a kernel-internal timekeeping interface to add or subtract a fixed amount from CLOCK_REALTIME. This makes it so kernel users or interfaces trying to do so do not have to read the time, then add an offset and then call settimeofday(), which adds some extra error in comparision to just simply adding the offset in the kernel timekeeping core. Signed-off-by: NJohn Stultz <john.stultz@linaro.org> Signed-off-by: NRichard Cochran <richard.cochran@omicron.at> LKML-Reference: <20110201134419.584311693@linutronix.de> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 Richard Cochran 提交于
Both settimeofday() and clock_settime() promise with a 'const' attribute not to alter the arguments passed in. This patch adds the missing 'const' attribute into the various kernel functions implementing these calls. Signed-off-by: NRichard Cochran <richard.cochran@omicron.at> Acked-by: NJohn Stultz <johnstul@us.ibm.com> LKML-Reference: <20110201134417.545698637@linutronix.de> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 31 1月, 2011 4 次提交
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由 Torben Hohn 提交于
xtime_update() takes xtime_lock write locked and calls do_timer(). Provided to replace the do_timer() calls in the architecture code. Signed-off-by: NTorben Hohn <torbenh@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: johnstul@us.ibm.com Cc: yong.zhang0@gmail.com Cc: hch@infradead.org LKML-Reference: <20110127145910.23248.21379.stgit@localhost> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 Thomas Gleixner 提交于
No users left. Remove it. Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 Torben Hohn 提交于
The hrtimer code accesses timekeeping variables under xtime_lock. Provide a sensible accessor function and use it. [ tglx: Removed the conditionals, unused variable, fixed codingstyle and massaged changelog ] Signed-off-by: NTorben Hohn <torbenh@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: johnstul@us.ibm.com Cc: yong.zhang0@gmail.com Cc: hch@infradead.org LKML-Reference: <20110127145905.23248.30458.stgit@localhost> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 Torben Hohn 提交于
do_timer() is primary timekeeping related. calc_global_load() is called from do_timer() as well, but that's more for historical reasons. [ tglx: Fixed up the calc_global_load() reject andmassaged changelog ] Signed-off-by: NTorben Hohn <torbenh@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: johnstul@us.ibm.com Cc: yong.zhang0@gmail.com Cc: hch@infradead.org LKML-Reference: <20110127145855.23248.56933.stgit@localhost> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 14 1月, 2011 1 次提交
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由 Alexander Gordeev 提交于
MONOTONIC_RAW clock timestamps are ideally suited for frequency calculation and also fit well into the original NTP hardpps design. Now phase and frequency can be adjusted separately: the former based on REALTIME clock and the latter based on MONOTONIC_RAW clock. A new function getnstime_raw_and_real is added to timekeeping subsystem to capture both timestamps at the same time and atomically. Signed-off-by: NAlexander Gordeev <lasaine@lvk.cs.msu.su> Acked-by: NJohn Stultz <johnstul@us.ibm.com> Cc: Rodolfo Giometti <giometti@enneenne.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 12 1月, 2011 1 次提交
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由 H Hartley Sweeten 提交于
Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com> Cc: John Stultz <johnstul@us.ibm.com> LKML-Reference: <0D753D10438DA54287A00B027084269764CE0E54B7@AUSP01VMBX24.collaborationhost.net> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 21 10月, 2010 1 次提交
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由 Kasper Pedersen 提交于
When the clocksource is not a multiple of HZ, the clock will be off. For acpi_pm, HZ=1000 the error is 127.111 ppm: The rounding of cycle_interval ends up generating a false error term in ntp_error accumulation since xtime_interval is not exactly 1/HZ. So, we subtract out the error caused by the rounding. This has been visible since 2.6.32-rc2 commit a092ff0f time: Implement logarithmic time accumulation That commit raised NTP_INTERVAL_FREQ and exposed the rounding error. testing tool: http://n1.taur.dk/permanent/testpmt.c Also tested with ntpd and a frequency counter. Signed-off-by: NKasper Pedersen <kkp2010@kasperkp.dk> Acked-by: Njohn stultz <johnstul@us.ibm.com> Cc: John Kacur <jkacur@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 14 8月, 2010 1 次提交
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由 John Stultz 提交于
Early 4.3 versions of gcc apparently aggressively optimize the raw time accumulation loop, replacing it with a divide. On 32bit systems, this causes the following link errors: undefined reference to `__umoddi3' undefined reference to `__udivdi3' The gcc issue has been fixed in 4.4 and greater. This patch replaces the accumulation loop with a do_div, as suggested by Linus. Signed-off-by: NJohn Stultz <johnstul@us.ibm.com> CC: Jason Wessel <jason.wessel@windriver.com> CC: Larry Finger <Larry.Finger@lwfinger.net> CC: Ingo Molnar <mingo@elte.hu> CC: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 13 8月, 2010 1 次提交
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由 Jason Wessel 提交于
The tv_nsec is a long and when added to the shifted interval it can wrap and become negative which later causes looping problems in the getrawmonotonic(). The edge case occurs when the system has slept for a short period of time of ~2 seconds. A trace printk of the values in this patch illustrate the problem: ftrace time stamp: log 43.716079: logarithmic_accumulation: raw: 3d0913 tv_nsec d687faa 43.718513: logarithmic_accumulation: raw: 3d0913 tv_nsec da588bd 43.722161: logarithmic_accumulation: raw: 3d0913 tv_nsec de291d0 46.349925: logarithmic_accumulation: raw: 7a122600 tv_nsec e1f9ae3b 46.349930: logarithmic_accumulation: raw: 1e848980 tv_nsec 8831c0e3 The kernel starts looping at 46.349925 in the getrawmonotonic() due to the negative value from adding the raw value to tv_nsec. A simple solution is to accumulate into a u64, and then normalize it to a timespec_t. Signed-off-by: NJason Wessel <jason.wessel@windriver.com> [ Reworked variable names and simplified some of the code. - John ] Signed-off-by: NJohn Stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: H. Peter Anvin <hpa@zytor.com> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 27 7月, 2010 5 次提交
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由 John Stultz 提交于
This patch makes xtime and wall_to_monotonic static, as planned in Documentation/feature-removal-schedule.txt. This will allow for further cleanups to the timekeeping core. Signed-off-by: NJohn Stultz <johnstul@us.ibm.com> LKML-Reference: <1279068988-21864-10-git-send-email-johnstul@us.ibm.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 John Stultz 提交于
Provides an accessor function to replace hrtimer.c's direct access of wall_to_monotonic. This will allow wall_to_monotonic to be made static as planned in Documentation/feature-removal-schedule.txt Signed-off-by: NJohn Stultz <johnstul@us.ibm.com> LKML-Reference: <1279068988-21864-9-git-send-email-johnstul@us.ibm.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 John Stultz 提交于
update_vsyscall() did not provide the wall_to_monotoinc offset, so arch specific implementations tend to reference wall_to_monotonic directly. This limits future cleanups in the timekeeping core, so this patch fixes the update_vsyscall interface to provide wall_to_monotonic, allowing wall_to_monotonic to be made static as planned in Documentation/feature-removal-schedule.txt Signed-off-by: NJohn Stultz <johnstul@us.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Anton Blanchard <anton@samba.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Tony Luck <tony.luck@intel.com> LKML-Reference: <1279068988-21864-7-git-send-email-johnstul@us.ibm.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 John Stultz 提交于
Now that all arches have been converted over to use generic time via clocksources or arch_gettimeoffset(), we can remove the GENERIC_TIME config option and simplify the generic code. Signed-off-by: NJohn Stultz <johnstul@us.ibm.com> LKML-Reference: <1279068988-21864-4-git-send-email-johnstul@us.ibm.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 John Stultz 提交于
After accidentally misusing timespec_add_safe, I wanted to make sure we don't accidently trip over that issue again, so I created a simple timespec_add() function which we can use to replace the instances of timespec_add_safe() that don't want the overflow detection. Signed-off-by: NJohn Stultz <johnstul@us.ibm.com> LKML-Reference: <1279068988-21864-3-git-send-email-johnstul@us.ibm.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 13 4月, 2010 1 次提交
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由 John Stultz 提交于
With the earlier logarithmic time accumulation patch, xtime will now always be within one "tick" of the current time, instead of possibly half a second off. This removes the need for the xtime_cache value, which always stored the time at the last interrupt, so this patch cleans that up removing the xtime_cache related code. This patch also addresses an issue with an earlier version of this change, where xtime_cache was normalizing xtime, which could in some cases be not valid (ie: tv_nsec == NSEC_PER_SEC). This is fixed by handling the edge case in update_wall_time(). Signed-off-by: NJohn Stultz <johnstul@us.ibm.com> Cc: Petr Titěra <P.Titera@century.cz> LKML-Reference: <1270589451-30773-1-git-send-email-johnstul@us.ibm.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 23 3月, 2010 1 次提交
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由 John Stultz 提交于
The logarithmic accumulation done in the timekeeping has some overflow protection that limits the max shift value. That means it will take more then shift loops to accumulate all of the cycles. This causes the shift decrement to underflow, which causes the loop to never exit. The simplest fix would be simply to do a: if (shift) shift--; However that is not optimal, as we know the cycle offset is larger then the interval << shift, the above would make shift drop to zero, then we would be spinning for quite awhile accumulating at interval chunks at a time. Instead, this patch only decreases shift if the offset is smaller then cycle_interval << shift. This makes sure we accumulate using the largest chunks possible without overflowing tick_length, and limits the number of iterations through the loop. This issue was found and reported by Sonic Zhang, who also tested the fix. Many thanks your explanation and testing! Reported-by: NSonic Zhang <sonic.adi@gmail.com> Signed-off-by: NJohn Stultz <johnstul@us.ibm.com> Tested-by: NSonic Zhang <sonic.adi@gmail.com> LKML-Reference: <1268948850-5225-1-git-send-email-johnstul@us.ibm.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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