1. 20 Feb, 2008 1 commit
    • Hidetoshi Seto's avatar
      [IA64] VIRT_CPU_ACCOUNTING (accurate cpu time accounting) · b64f34cd
      Hidetoshi Seto authored
      
      
      This patch implements VIRT_CPU_ACCOUNTING for ia64,
      which enable us to use more accurate cpu time accounting.
      
      The VIRT_CPU_ACCOUNTING is an item of kernel config, which s390
      and powerpc arch have.  By turning this config on, these archs
      change the mechanism of cpu time accounting from tick-sampling
      based one to state-transition based one.
      
      The state-transition based accounting is done by checking time
      (cycle counter in processor) at every state-transition point,
      such as entrance/exit of kernel, interrupt, softirq etc.
      The difference between point to point is the actual time consumed
      during in the state. There is no doubt about that this value is
      more accurate than that of tick-sampling based accounting.
      Signed-off-by: default avatarHidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
      Signed-off-by: default avatarTony Luck <tony.luck@intel.com>
      b64f34cd
  2. 19 Feb, 2008 39 commits