• Tetsuo Handa's avatar
    kernel/hung_task.c: use timeout diff when timeout is updated · b4aa14a6
    Tetsuo Handa authored
    When new timeout is written to /proc/sys/kernel/hung_task_timeout_secs,
    khungtaskd is interrupted and again sleeps for full timeout duration.
    This means that hang task will not be checked if new timeout is written
    periodically within old timeout duration and/or checking of hang task
    will be delayed for up to previous timeout duration.  Fix this by
    remembering last time khungtaskd checked hang task.
    This change will allow other watchdog tasks (if any) to share khungtaskd
    by sleeping for minimal timeout diff of all watchdog tasks.  Doing more
    watchdog tasks from khungtaskd will reduce the possibility of printk()
    collisions by multiple watchdog threads.
    Signed-off-by: default avatarTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
    Cc: Oleg Nesterov <oleg@redhat.com>
    Cc: Aaron Tomlin <atomlin@redhat.com>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
hung_task.c 5.85 KB