cvs commit: src/sys/dev/acpica acpi_timer.c

[Nate Lawson]

njl         2004/04/24 09:25:00 PDT

  FreeBSD src repository

  Modified files:
    sys/dev/acpica       acpi_timer.c 
  Log:
  Disable interrupts while testing the timer.  Not doing this unnecessarily
  added an arbitrary delay to our readings, causing us to use the ACPI-safe
  read method when not necessary.  Submitted by: bde
  
  Old:
  ACPI timer looks GOOD min = 3, max = 5, width = 2
  ACPI timer looks BAD  min = 3, max = 19, width = 16
  ACPI timer looks GOOD min = 3, max = 5, width = 2
  ACPI timer looks GOOD min = 3, max = 5, width = 2
  ACPI timer looks GOOD min = 3, max = 5, width = 2
  ACPI timer looks GOOD min = 3, max = 4, width = 1
  ACPI timer looks GOOD min = 3, max = 5, width = 2
  ACPI timer looks BAD  min = 3, max = 19, width = 16
  ACPI timer looks GOOD min = 3, max = 5, width = 2
  ACPI timer looks GOOD min = 3, max = 4, width = 1
  Timecounter "ACPI-safe" frequency 3579545 Hz quality 1000
  
  New:
  ACPI timer looks GOOD min = 3, max = 4, width = 1
  ACPI timer looks GOOD min = 3, max = 4, width = 1
  ACPI timer looks GOOD min = 3, max = 4, width = 1
  ACPI timer looks GOOD min = 3, max = 4, width = 1
  ACPI timer looks GOOD min = 3, max = 4, width = 1
  ACPI timer looks GOOD min = 3, max = 4, width = 1
  ACPI timer looks GOOD min = 3, max = 4, width = 1
  ACPI timer looks GOOD min = 3, max = 4, width = 1
  ACPI timer looks GOOD min = 3, max = 4, width = 1
  ACPI timer looks GOOD min = 3, max = 4, width = 1
  Timecounter "ACPI-fast" frequency 3579545 Hz quality 1000
  
  Also, reduce unnecesary overhead in ACPI-fast by remove the barrier for
  reads.  The timer in the ACPI-fast case is known to increase monotonically
  so there is no need to serialize access to it.
  
  Revision  Changes    Path
  1.32      +7 -6      src/sys/dev/acpica/acpi_timer.c