1. 08 4月, 2007 1 次提交
    • I
      [PATCH] high-res timers: resume fix · 995f054f
      Ingo Molnar 提交于
      Soeren Sonnenburg reported that upon resume he is getting
      this backtrace:
      
       [<c0119637>] smp_apic_timer_interrupt+0x57/0x90
       [<c0142d30>] retrigger_next_event+0x0/0xb0
       [<c0104d30>] apic_timer_interrupt+0x28/0x30
       [<c0142d30>] retrigger_next_event+0x0/0xb0
       [<c0140068>] __kfifo_put+0x8/0x90
       [<c0130fe5>] on_each_cpu+0x35/0x60
       [<c0143538>] clock_was_set+0x18/0x20
       [<c0135cdc>] timekeeping_resume+0x7c/0xa0
       [<c02aabe1>] __sysdev_resume+0x11/0x80
       [<c02ab0c7>] sysdev_resume+0x47/0x80
       [<c02b0b05>] device_power_up+0x5/0x10
      
      it turns out that on resume we mistakenly re-enable interrupts too
      early.  Do the timer retrigger only on the current CPU.
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      Acked-by: NThomas Gleixner <tglx@linutronix.de>
      Acked-by: NSoeren Sonnenburg <kernel@nn7.de>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      995f054f
  2. 26 3月, 2007 1 次提交
  3. 07 3月, 2007 2 次提交
  4. 05 3月, 2007 1 次提交
    • H
      [PATCH] timer/hrtimer: take per cpu locks in sane order · e81ce1f7
      Heiko Carstens 提交于
      Doing something like this on a two cpu system
      
        # echo 0 > /sys/devices/system/cpu/cpu0/online
        # echo 1 > /sys/devices/system/cpu/cpu0/online
        # echo 0 > /sys/devices/system/cpu/cpu1/online
      
      will give me this:
      
        =======================================================
        [ INFO: possible circular locking dependency detected ]
        2.6.21-rc2-g562aa1d4-dirty #7
        -------------------------------------------------------
        bash/1282 is trying to acquire lock:
         (&cpu_base->lock_key){.+..}, at: [<000000000005f17e>] hrtimer_cpu_notify+0xc6/0x240
      
        but task is already holding lock:
         (&cpu_base->lock_key#2){.+..}, at: [<000000000005f174>] hrtimer_cpu_notify+0xbc/0x240
      
        which lock already depends on the new lock.
      
      This happens because we have the following code in kernel/hrtimer.c:
      
        migrate_hrtimers(int cpu)
        [...]
        old_base = &per_cpu(hrtimer_bases, cpu);
        new_base = &get_cpu_var(hrtimer_bases);
        [...]
        spin_lock(&new_base->lock);
        spin_lock(&old_base->lock);
      
      Which means the spinlocks are taken in an order which depends on which cpu
      gets shut down from which other cpu. Therefore lockdep complains that there
      might be an ABBA deadlock. Since migrate_hrtimers() gets only called on
      cpu hotplug it's safe to assume that it isn't executed concurrently on a
      
      The same problem exists in kernel/timer.c: migrate_timers().
      
      As pointed out by Christian Borntraeger one possible solution to avoid
      the locking order complaints would be to make sure that the locks are
      always taken in the same order. E.g. by taking the lock of the cpu with
      the lower number first.
      
      To achieve this we introduce two new spinlock functions double_spin_lock
      and double_spin_unlock which lock or unlock two locks in a given order.
      
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Roman Zippel <zippel@linux-m68k.org>
      Cc: John Stultz <johnstul@us.ibm.com>
      Cc: Christian Borntraeger <cborntra@de.ibm.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      e81ce1f7
  5. 02 3月, 2007 2 次提交
  6. 17 2月, 2007 11 次提交
  7. 13 2月, 2007 1 次提交
    • E
      [PATCH] x86-64: get rid of ARCH_HAVE_XTIME_LOCK · 5809f9d4
      Eric Dumazet 提交于
      ARCH_HAVE_XTIME_LOCK is used by x86_64 arch .  This arch needs to place a
      read only copy of xtime_lock into vsyscall page.  This read only copy is
      named __xtime_lock, and xtime_lock is defined in
      arch/x86_64/kernel/vmlinux.lds.S as an alias.  So the declaration of
      xtime_lock in kernel/timer.c was guarded by ARCH_HAVE_XTIME_LOCK define,
      defined to true on x86_64.
      
      We can get same result with _attribute__((weak)) in the declaration. linker
      should do the job.
      Signed-off-by: NEric Dumazet <dada1@cosmosbay.com>
      Signed-off-by: NAndi Kleen <ak@suse.de>
      Cc: Andi Kleen <ak@suse.de>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      5809f9d4
  8. 12 2月, 2007 3 次提交
  9. 23 12月, 2006 1 次提交
  10. 14 12月, 2006 1 次提交
    • E
      [PATCH] Optimize calc_load() · cd7175ed
      Eric Dumazet 提交于
      calc_load() is called by timer interrupt to update avenrun[].  It currently
      calls nr_active() at each timer tick (HZ per second), while the update of
      avenrun[] is done only once every 5 seconds.  (LOAD_FREQ=5 Hz)
      
      nr_active() is quite expensive on SMP machines, since it has to sum up
      nr_running and nr_uninterruptible of all online CPUS, bringing foreign
      dirty cache lines.
      
      This patch is an optimization of calc_load() so that nr_active() is called
      only if we need it.
      
      The use of unlikely() is welcome since the condition is true only once every
      5*HZ time.
      Signed-off-by: NEric Dumazet <dada1@cosmosbay.com>
      Cc: Ingo Molnar <mingo@elte.hu>
      Acked-by: N"Siddha, Suresh B" <suresh.b.siddha@intel.com>
      Cc: Nick Piggin <nickpiggin@yahoo.com.au>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      cd7175ed
  11. 11 12月, 2006 2 次提交
  12. 01 10月, 2006 4 次提交
    • A
      [PATCH] kill wall_jiffies · 8ef38609
      Atsushi Nemoto 提交于
      With 2.6.18-rc4-mm2, now wall_jiffies will always be the same as jiffies.
      So we can kill wall_jiffies completely.
      
      This is just a cleanup and logically should not change any real behavior
      except for one thing: RTC updating code in (old) ppc and xtensa use a
      condition "jiffies - wall_jiffies == 1".  This condition is never met so I
      suppose it is just a bug.  I just remove that condition only instead of
      kill the whole "if" block.
      
      [heiko.carstens@de.ibm.com: s390 build fix and cleanup]
      Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
      Cc: Andi Kleen <ak@muc.de>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Richard Henderson <rth@twiddle.net>
      Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
      Cc: Russell King <rmk@arm.linux.org.uk>
      Cc: Ian Molton <spyro@f2s.com>
      Cc: Mikael Starvik <starvik@axis.com>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Cc: Hirokazu Takata <takata.hirokazu@renesas.com>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Kyle McMartin <kyle@mcmartin.ca>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Paul Mundt <lethal@linux-sh.org>
      Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp>
      Cc: Richard Curnow <rc@rc0.org.uk>
      Cc: William Lee Irwin III <wli@holomorphy.com>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Jeff Dike <jdike@addtoit.com>
      Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
      Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp>
      Cc: Chris Zankel <chris@zankel.net>
      Cc: "Luck, Tony" <tony.luck@intel.com>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Roman Zippel <zippel@linux-m68k.org>
      Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      8ef38609
    • R
      [PATCH] ntp: add time_adjust to tick length · 8f807f8d
      Roman Zippel 提交于
      This folds update_ntp_one_tick() into second_overflow() and adds time_adjust
      to the tick length, this makes time_next_adjust unnecessary.  This slightly
      changes the adjtime() behaviour, instead of applying it to the next tick, it's
      applied to the next second.
      Signed-off-by: NRoman Zippel <zippel@linux-m68k.org>
      Cc: john stultz <johnstul@us.ibm.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      8f807f8d
    • R
      [PATCH] ntp: add ntp_update_frequency · b0ee7556
      Roman Zippel 提交于
      This introduces ntp_update_frequency() and deinlines ntp_clear() (as it's not
      performance critical).  ntp_update_frequency() calculates the base tick length
      using tick_usec and adds a base adjustment, in case the frequency doesn't
      divide evenly by HZ.
      Signed-off-by: NRoman Zippel <zippel@linux-m68k.org>
      Cc: john stultz <johnstul@us.ibm.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      b0ee7556
    • J
      [PATCH] NTP: Move all the NTP related code to ntp.c · 4c7ee8de
      john stultz 提交于
      Move all the NTP related code to ntp.c
      
      [akpm@osdl.org: cleanups, build fix]
      Signed-off-by: NJohn Stultz <johnstul@us.ibm.com>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Roman Zippel <zippel@linux-m68k.org>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      4c7ee8de
  13. 30 9月, 2006 4 次提交
  14. 15 8月, 2006 1 次提交
  15. 01 8月, 2006 3 次提交
  16. 15 7月, 2006 2 次提交