• Andrew Morton's avatar
    [PATCH] MSEC_TO_JIFFIES consolidation · 5b59eadf
    Andrew Morton authored
    From: Ingo Molnar <mingo@elte.hu>
    
    We have various different implementations of MSEC[S]_TO_JIFFIES and
    JIFFIES_TO_MSEC[S].  We recently had a compile-time clash in USB.
    
    Fix all that up.
    
    - The SCTP version was very inefficient.  Hopefully this version is accurate
      enough.
    
    - Optimise for the HZ=100 and HZ=1000 cases
    
    - This version does round-up, so sleep(9 milliseconds) works OK on 100HZ.
    
    - We still have lots of jiffies_to_msec and msec_to_jiffies implementations.
    
    From: William Lee Irwin III <wli@holomorphy.com>
    
      Optimize the cases where HZ is a divisor of 1000 or vice-versa in
      JIFFIES_TO_MSECS() and MSECS_TO_JIFFIES() by allowing the nonvanishing(!)
      integral ratios to appear as a parenthesized expressions eligible for
      constant folding optimizations.
    
    From: me
    
      Use typesafe inlines for the jiffies-to-millisecond conversion functions.
    
      This means that milliseconds officially takes the type `unsigned int'.
      All current callers seem to be OK with that.
    
      Drivers need to be fixed up to use this instead of their private versions.
    5b59eadf
irda.h 3.27 KB