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    ARM: sched_clock: make minsec argument to clocks_calc_mult_shift() zero · edc4d272
    Russell King authored
    
    
    The purpose of the minsec argument is to prevent 64-bit math overflow
    when the number of cycles is multiplied up.  However, the multipler
    is 32-bit, and in the sched_clock() case, the cycle counter is up to
    32-bit as well.  So the math can never overflow.
    
    With a value of 60, and clock rates greater than 71MHz, the calculated
    multiplier is unnecessarily reduced in value, which reduces accuracy by
    maybe 70ppt.  It's almost not worth bothering with as the oscillator
    driving the counter won't be any more than 1ppm - unless you're using
    a rubidium lamp or caesium fountain frequency standard.
    
    So, set the minsec argument to zero.
    
    Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
    edc4d272