• Ryan Thibodeaux's avatar
    x86/xen: Add "xen_timer_slop" command line option · 2ec16bc0
    Ryan Thibodeaux authored
    Add a new command-line option "xen_timer_slop=<INT>" that sets the
    minimum delta of virtual Xen timers. This commit does not change the
    default timer slop value for virtual Xen timers.
    
    Lowering the timer slop value should improve the accuracy of virtual
    timers (e.g., better process dispatch latency), but it will likely
    increase the number of virtual timer interrupts (relative to the
    original slop setting).
    
    The original timer slop value has not changed since the introduction
    of the Xen-aware Linux kernel code. This commit provides users an
    opportunity to tune timer performance given the refinements to
    hardware and the Xen event channel processing. It also mirrors
    a feature in the Xen hypervisor - the "timer_slop" Xen command line
    option.
    
    [boris: updated comment describing TIMER_SLOP]
    Signed-off-by: default avatarRyan Thibodeaux <ryan.thibodeaux@starlab.io>
    Reviewed-by: default avatarBoris Ostrovsky <boris.ostrovsky@oracle.com>
    Signed-off-by: default avatarBoris Ostrovsky <boris.ostrovsky@oracle.com>
    2ec16bc0
time.c 14.9 KB