1. 02 9月, 2006 9 次提交
    • O
      [PATCH] exit early in floppy_init when no floppy exists · ef16b519
      Olaf Hering 提交于
      modprobe -v floppy on a Apple G5 writes incorrect stuff to dmesg:
      
      Floppy drive(s): fd0 is 2.88M
      
      The reason is that the legacy io check happens very late,
      when part of the floppy stuff is already initialized.
      check_legacy_ioport() returns either -ENODEV right away, or it walks
      the device-tree looking for a floppy node.
      Signed-off-by: NOlaf Hering <olaf@aepfle.de>
      Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      ef16b519
    • A
      [PATCH] x86: increase MAX_MP_BUSSES on default arch · a9aa141c
      Andrew Morton 提交于
      Vitezslav Samel <samel@mail.cz> reports that an HP DL380 g4 fails using the
      default arch due to the ISA bus having an ID of 32.
      
      It would have worked OK with the generic arch - for some reason the default
      arch doesn't support as many busses.
      
      So bump that up to support 256 busses, but leave it at 32 if we're building a
      tiny system to save a bit of memory.
      
      Cc: Vitezslav Samel <samel@mail.cz>
      Acked-by: NAndi Kleen <ak@muc.de>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      a9aa141c
    • B
      [PATCH] xtensa: ptrace: EXIT_ZOMBIE fix · d742eae8
      Bill Huey (hui 提交于
      We're testing the wrong task_struct field.
      Acked-by: NChris Zankel <chris@zankel.net>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      d742eae8
    • S
      [PATCH] task delay accounting fixes · 35df17c5
      Shailabh Nagar 提交于
      Cleanup allocation and freeing of tsk->delays used by delay accounting.
      This solves two problems reported for delay accounting:
      
      1. oops in __delayacct_blkio_ticks
      http://www.uwsg.indiana.edu/hypermail/linux/kernel/0608.2/1844.html
      
      Currently tsk->delays is getting freed too early in task exit which can
      cause a NULL tsk->delays to get accessed via reading of /proc/<tgid>/stats.
       The patch fixes this problem by freeing tsk->delays closer to when
      task_struct itself is freed up.  As a result, it also eliminates the use of
      tsk->delays_lock which was only being used (inadequately) to safeguard
      access to tsk->delays while a task was exiting.
      
      2. Possible memory leak in kernel/delayacct.c
      http://www.uwsg.indiana.edu/hypermail/linux/kernel/0608.2/1389.html
      
      The patch cleans up tsk->delays allocations after a bad fork which was
      missing earlier.
      
      The patch has been tested to fix the problems listed above and stress
      tested with rapid calls to delay accounting's taskstats command interface
      (which is the other path that can access the same data, besides the /proc
      interface causing the oops above).
      Signed-off-by: NShailabh Nagar <nagar@watson.ibm.com>
      Cc: Balbir Singh <balbir@in.ibm.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      35df17c5
    • J
      [PATCH] Fix faulty HPET clocksource usage (fix for bug #7062) · 30f3174d
      john stultz 提交于
      Apparently some systems export valid HPET addresses, but hpet_enable()
      fails.  Then when the HPET clocksource starts up, it only checks for a
      valid HPET address, and the result is a system where time does not advance.
      
      See http://bugme.osdl.org/show_bug.cgi?id=7062 for details.
      
      This patch just makes sure we better check that the HPET is functional
      before registering the HPET clocksource.
      Signed-off-by: NJohn Stultz <johnstul@us.ibm.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      30f3174d
    • P
      [PATCH] synclink_gt: fix receive tty error handling · 202af6d5
      Paul Fulghum 提交于
      Fix receive tty error handling in synclink_gt driver.  Adrian reported
      compiler warning for incorrect bit test against char variable.  I
      determined these and other device specific error bits were incorrectly
      defined.
      Signed-off-by: NPaul Fulghum <paulkf@microgate.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      202af6d5
    • N
      [PATCH] md: Fix issues with referencing rdev in md/raid1 · ddac7c7e
      NeilBrown 提交于
      We need to be careful when referencing mirrors[i].rdev.  It can disappear
      under us at various times.
      
      So:
        fix a couple of problem places.
        comment a couple of non-problem places
        move an 'atomic_add' which deferences rdev down a little
          way to some where where it is sure to not be NULL.
      Signed-off-by: NNeil Brown <neilb@suse.de>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      ddac7c7e
    • C
      [PATCH] ZVC: Scale thresholds depending on the size of the system · df9ecaba
      Christoph Lameter 提交于
      The ZVC counter update threshold is currently set to a fixed value of 32.
      This patch sets up the threshold depending on the number of processors and
      the sizes of the zones in the system.
      
      With the current threshold of 32, I was able to observe slight contention
      when more than 130-140 processors concurrently updated the counters.  The
      contention vanished when I either increased the threshold to 64 or used
      Andrew's idea of overstepping the interval (see ZVC overstep patch).
      
      However, we saw contention again at 220-230 processors.  So we need higher
      values for larger systems.
      
      But the current default is already a bit of an overkill for smaller
      systems.  Some systems have tiny zones where precision matters.  For
      example i386 and x86_64 have 16M DMA zones and either 900M ZONE_NORMAL or
      ZONE_DMA32.  These are even present on SMP and NUMA systems.
      
      The patch here sets up a threshold based on the number of processors in the
      system and the size of the zone that these counters are used for.  The
      threshold should grow logarithmically, so we use fls() as an easy
      approximation.
      
      Results of tests on a system with 1024 processors (4TB RAM)
      
      The following output is from a test allocating 1GB of memory concurrently
      on each processor (Forking the process.  So contention on mmap_sem and the
      pte locks is not a factor):
      
                             X                   MIN
      TYPE:               CPUS       WALL       WALL        SYS     USER     TOTCPU
      fork                   1      0.552      0.552      0.540    0.012      0.552
      fork                   4      0.552      0.548      2.164    0.036      2.200
      fork                  16      0.564      0.548      8.812    0.164      8.976
      fork                 128      0.580      0.572     72.204    1.208     73.412
      fork                 256      1.300      0.660    310.400    2.160    312.560
      fork                 512      3.512      0.696   1526.836    4.816   1531.652
      fork                1020     20.024      0.700  17243.176    6.688  17249.863
      
      So a threshold of 32 is fine up to 128 processors. At 256 processors contention
      becomes a factor.
      
      Overstepping the counter (earlier patch) improves the numbers a bit:
      
      fork                   4      0.552      0.548      2.164    0.040      2.204
      fork                  16      0.552      0.548      8.640    0.148      8.788
      fork                 128      0.556      0.548     69.676    0.956     70.632
      fork                 256      0.876      0.636    212.468    2.108    214.576
      fork                 512      2.276      0.672    997.324    4.260   1001.584
      fork                1020     13.564      0.680  11586.436    6.088  11592.523
      
      Still contention at 512 and 1020. Contention at 1020 is down by a third.
      256 still has a slight bit of contention.
      
      After this patch the counter threshold will be set to 125 which reduces
      contention significantly:
      
      fork                 128      0.560      0.548     69.776    0.932     70.708
      fork                 256      0.636      0.556    143.460    2.036    145.496
      fork                 512      0.640      0.548    284.244    4.236    288.480
      fork                1020      1.500      0.588   1326.152    8.892   1335.044
      
      [akpm@osdl.org: !SMP build fix]
      Signed-off-by: NChristoph Lameter <clameter@sgi.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      df9ecaba
    • C
      [PATCH] ZVC: Overstep counters · a302eb4e
      Christoph Lameter 提交于
      Increments and decrements are usually grouped rather than mixed.  We can
      optimize the inc and dec functions for that case.
      
      Increment and decrement the counters by 50% more than the threshold in
      those cases and set the differential accordingly.  This decreases the need
      to update the atomic counters.
      
      The idea came originally from Andrew Morton.  The overstepping alone was
      sufficient to address the contention issue found when updating the global
      and the per zone counters from 160 processors.
      
      Also remove some code in dec_zone_page_state.
      Signed-off-by: NChristoph Lameter <clameter@sgi.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      a302eb4e
  2. 01 9月, 2006 7 次提交
  3. 31 8月, 2006 24 次提交