• Jeff Dike's avatar
    uml: tickless support · d2753a6d
    Jeff Dike authored
    Enable tickless support.
    
    CONFIG_TICK_ONESHOT and CONFIG_NO_HZ are enabled.
    
    itimer_clockevent gets CLOCK_EVT_FEAT_ONESHOT and an implementation of
    .set_next_event.
    
    CONFIG_UML_REAL_TIME_CLOCK goes away because it only makes sense when there is
    a clock ticking away all the time.  timer_handler now just calls do_IRQ once
    without trying to figure out how many ticks to emulate.
    
    The idle loop now needs to turn ticking on and off.
    
    Userspace ticks keep happening as usual.  However, the userspace loop keep
    track of when the next wakeup should happen and suppresses process ticks until
    that happens.
    Signed-off-by: default avatarJeff Dike <jdike@linux.intel.com>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    d2753a6d
defconfig 11.1 KB