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  1. 16 Sep, 2007 3 commits
    • Thomas Gleixner's avatar
      timekeeping: Prevent time going backwards on resume · 6a669ee8
      Thomas Gleixner authored 
      Timekeeping resume adjusts xtime by adding the slept time in seconds and
resets the reference value of the clock source (clock->cycle_last).
clock->cycle last is used to calculate the delta between the last xtime
update and the readout of the clock source in __get_nsec_offset(). xtime
plus the offset is the current time. The resume code ignores the delta
which had already elapsed between the last xtime update and the actual
time of suspend. If the suspend time is short, then we can see time
going backwards on resume.

Suspend:
offs_s = clock->read() - clock->cycle_last;
now = xtime + offs_s;
timekeeping_suspend_time = read_rtc();

Resume:
sleep_time = read_rtc() - timekeeping_suspend_time;
xtime.tv_sec += sleep_time;
clock->cycle_last = clock->read();
offs_r = clock->read() - clock->cycle_last;
now = xtime + offs_r;

if sleep_time_seconds == 0 and offs_r < offs_s, then time goes
backwards.

Fix this by storing the offset from the last xtime update and add it to
xtime during resume, when we reset clock->cycle_last:

sleep_time = read_rtc() - timekeeping_suspend_time;
xtime.tv_sec += sleep_time;
xtime += offs_s;	/* Fixup xtime offset at suspend time */
clock->cycle_last = clock->read();
offs_r = clock->read() - clock->cycle_last;
now = xtime + offs_r;

Thanks to Marcelo for tracking this down on the OLPC and providing the
necessary details to analyze the root cause.
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Tosatti <marcelo@kvack.org>
      6a669ee8
    • Thomas Gleixner's avatar
      timekeeping: access rtc outside of xtime lock · 3be90950
      Thomas Gleixner authored 
      Lockdep complains about the access of rtc in timekeeping_suspend
inside the interrupt disabled region of the write locked xtime lock.
Move the access outside.
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <johnstul@us.ibm.com>
      3be90950
    • Linus Torvalds's avatar
      Merge branch 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/netdev-2.6 · d0174640
      Linus Torvalds authored 
      * 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/netdev-2.6:
  drivers/net/pcmcia/3c589_cs: fix port configuration switcheroo
  sk98lin: resurrect driver
  ucc_geth: fix compilation
  mv643xx_eth: Fix tx_bytes stats calculation
  As struct iw_point is bi-directional payload, we should copy back the content
  [PATCH] bcm43xx: Fix cancellation of work queue crashes
  spidernet: fix interrupt reason recognition
  ehea: fix last_rx update
  ehea: propagate physical port state
  Fix a lock problem in generic phy code
  sky2: restore multicast list on resume and other ops
  atl1: disable broken 64-bit DMA
      d0174640
  3. 15 Sep, 2007 7 commits
  5. 14 Sep, 2007 25 commits
  7. 13 Sep, 2007 5 commits
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