Eric Lee / smarc-fsl-linux-kernel

05 Apr, 2011

2 commits

  • 21b86bd5a   Documentation: update kmemleak arch. info ... Browse Code »

    Besides x86 and arm, kmemleak now supports powerpc, sparc, sh,
    microblaze and tile.

    Signed-off-by: Daniel Baluta
    Acked-by: Catalin Marinas
    Signed-off-by: Randy Dunlap
    Signed-off-by: Linus Torvalds

    Daniel Baluta
     
  • a5660b41a   tty: fix endless work loop when the buffer fills up ... Browse Code »

    Commit f23eb2b2b285 ('tty: stop using "delayed_work" in the tty layer')
    ended up causing hung machines on UP with no preemption, because the
    work routine to flip the buffer data to the ldisc would endlessly re-arm
    itself if the destination buffer had filled up.

    With the delayed work, that only caused a timer-driving polling of the
    tty state every timer tick, but without the delay we just ended up with
    basically a busy loop instead.

    Stop the insane polling, and instead make the code that opens up the
    receive room re-schedule the buffer flip work. That's what we should
    have been doing anyway.

    This same "poll for tty room" issue is almost certainly also the cause
    of excessive kworker activity when idle reported by Dave Jones, who also
    reported "flush_to_ldisc executing 2500 times a second" back in Nov 2010:

    http://lkml.org/lkml/2010/11/30/592

    which is that silly flushing done every timer tick. Wasting both power
    and CPU for no good reason.

    Reported-and-tested-by: Alexander Beregalov
    Reported-and-tested-by: Sitsofe Wheeler
    Cc: Greg KH
    Cc: Alan Cox
    Cc: Dave Jones
    Signed-off-by: Linus Torvalds

    Linus Torvalds
     

04 Apr, 2011

10 commits

02 Apr, 2011

11 commits

01 Apr, 2011

17 commits