linux/kernel/time, branch v2.6.22.19

Fix timer_stats printout of events/sec

2007-10-10T17:50:16Z

commit 74922be1485818ed368c4cf4f0b100f70bf01e08 upstream. When using /proc/timer_stats on ppc64 I noticed the events/sec field wasnt accurate. Sometimes the integer part was incorrect due to rounding (we werent taking the fractional seconds into consideration). The fraction part is also wrong, we need to pad the printf statement and take the bottom three digits of 1000 times the value. Signed-off-by: Anton Blanchard Acked-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Fix leaks on /proc/{*/sched, sched_debug, timer_list, timer_stats}

2007-08-09T21:27:36Z

On every open/close one struct seq_operations leaks. Kudos to /proc/slab_allocators. Signed-off-by: Alexey Dobriyan Acked-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

NTP: remove clock_was_set() call to prevent deadlock

2007-07-03T20:54:27Z

The clock_was_set() call in seconds_overflow() which happens only when leap seconds are inserted / deleted is wrong in two aspects: 1. it results in a call to on_each_cpu() with interrupts disabled 2. it is potential deadlock source vs. call_lock in smp_call_function() The only possible side effect of the removal might be, that an absolute CLOCK_REALTIME timer fires 1 second too late, in the rare case of leap second deletion and an absolute CLOCK_REALTIME timer which expires in the affected time frame. It will never fire too early. This was probably observed by the reporter of a June 30th -> July 1st hang: http://lkml.org/lkml/2007/7/3/103 A similar problem was observed by Dave Jones, who provided a screen shot with a lockdep back trace, which allowed to analyse the problem. Signed-off-by: Thomas Gleixner Acked-by: Ingo Molnar Signed-off-by: Linus Torvalds

timer stats: speedups

2007-06-01T15:18:30Z

Make timer-stats have almost zero overhead when enabled in the config but not used. (this way distros can enable it more easily) Also update the documentation about overhead of timer_stats - it was written for the first version which had a global lock and a linear list walk based lookup ;-) Signed-off-by: Ingo Molnar Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

timer statistics: fix race

2007-06-01T15:18:30Z

Fix two races in the timer stats lookup code. One by ensuring that the initialization of a new entry is finished upon insertion of that entry. The other by cleaning up the hash table when the entries array is cleared, so that we don't have any "pre-inserted" entries. Thanks to Eric Dumazet for reminding me of the memory barriers. Signed-off-by: Bjorn Steinbrink Signed-off-by: Ian Kumlien Acked-by: Ingo Molnar Cc: Eric Dumazet Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

NOHZ: prevent multiplication overflow - stop timer for huge timeouts

2007-05-30T01:11:10Z

get_next_timer_interrupt() returns a delta of (LONG_MAX > 1) in case there is no timer pending. On 64 bit machines this results in a multiplication overflow in tick_nohz_stop_sched_tick(). Reported by: Dave Miller Make the return value a constant and limit the return value to a 32 bit value. When the max timeout value is returned, we can safely stop the tick timer device. The max jiffies delta results in a 12 days timeout for HZ=1000. In the long term the get_next_timer_interrupt() code needs to be reworked to return ktime instead of jiffies, but we have to wait until the last users of the original NO_IDLE_HZ code are converted. Signed-off-by: Thomas Gleixner Acked-off-by: David S. Miller Signed-off-by: Linus Torvalds

NOHZ: Rate limit the local softirq pending warning output

2007-05-24T03:14:11Z

The warning in the NOHZ code, which triggers when a CPU goes idle with softirqs pending can fill up the logs quite quickly. Rate limit the output until we found the root cause of that problem. Signed-off-by: Thomas Gleixner Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Ignore bogus ACPI info for offline CPUs

2007-05-24T03:14:11Z

Booting a SMP kernel with maxcpus=1 on a SMP system leads to a hard hang, because ACPI ignores the maxcpus setting and sends timer broadcast info for the offline CPUs. This results in a stuck for ever call to smp_call_function_single() on an offline CPU. Ignore the bogus information and print a kernel error to remind ACPI folks to fix it. Signed-off-by: Thomas Gleixner Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Detach sched.h from mm.h

2007-05-21T16:18:19Z

First thing mm.h does is including sched.h solely for can_do_mlock() inline function which has "current" dereference inside. By dealing with can_do_mlock() mm.h can be detached from sched.h which is good. See below, why. This patch a) removes unconditional inclusion of sched.h from mm.h b) makes can_do_mlock() normal function in mm/mlock.c c) exports can_do_mlock() to not break compilation d) adds sched.h inclusions back to files that were getting it indirectly. e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were getting them indirectly Net result is: a) mm.h users would get less code to open, read, preprocess, parse, ... if they don't need sched.h b) sched.h stops being dependency for significant number of files: on x86_64 allmodconfig touching sched.h results in recompile of 4083 files, after patch it's only 3744 (-8.3%). Cross-compile tested on all arm defconfigs, all mips defconfigs, all powerpc defconfigs, alpha alpha-up arm i386 i386-up i386-defconfig i386-allnoconfig ia64 ia64-up m68k mips parisc parisc-up powerpc powerpc-up s390 s390-up sparc sparc-up sparc64 sparc64-up um-x86_64 x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig as well as my two usual configs. Signed-off-by: Alexey Dobriyan Signed-off-by: Linus Torvalds

clocksource: fix lock order in the resume path

2007-05-15T15:54:00Z

lockdep complains about the lock nesting of clocksource and watchdog lock in the resume path. Change the resume marker to a bit operation and remove the lock from this path. Signed-off-by: Thomas Gleixner Cc: john stultz Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds