• Arjan van de Ven's avatar
    hrtimer: create a "timer_slack" field in the task struct · 6976675d
    Arjan van de Ven authored
    We want to be able to control the default "rounding" that is used by
    select() and poll() and friends. This is a per process property
    (so that we can have a "nice" like program to start certain programs with
    a looser or stricter rounding) that can be set/get via a prctl().
    
    For this purpose, a field called "timer_slack_ns" is added to the task
    struct. In addition, a field called "default_timer_slack"ns" is added
    so that tasks easily can temporarily to a more/less accurate slack and then
    back to the default.
    
    The default value of the slack is set to 50 usec; this is significantly less
    than 2.6.27's average select() and poll() timing error but still allows
    the kernel to group timers somewhat to preserve power behavior. Applications
    and admins can override this via the prctl()
    Signed-off-by: default avatarArjan van de Ven <arjan@linux.intel.com>
    6976675d
sys.c 42.4 KB