src/patches/suse-2.6.27.25/patches.suse/apm_setup_UP.diff

   1 From: Olaf Dabrunz <od@suse.de>
   2 Subject: [apm] default to "power_off" when SMP kernel is used on single processor machines
   3 Reference: SUSE221667
   4
   5 This patch turns on support for the APM power_off function by default when the
   6 SMP kernel is used on single processor machines.
   7
   8 It is a bit ugly to use a separate variable to make sure the default value is
   9 only used when needed and the power_off variable is not initialized twice. But
  10 I did not find a better way to do this with the way the current initialization
  11 system works.
  12
  13 Signed-off-by: Olaf Dabrunz <od@suse.de>
  14
  15
  16  arch/x86/kernel/apm_32.c |   15 ++++++++++++++-
  17  1 file changed, 14 insertions(+), 1 deletion(-)
  18
  19 --- a/arch/x86/kernel/apm_32.c
  20 +++ b/arch/x86/kernel/apm_32.c
  21 @@ -389,6 +389,7 @@ static int smp __read_mostly;
  22  static int apm_disabled = -1;
  23  #ifdef CONFIG_SMP
  24  static int power_off;
  25 +static int power_off_set;
  26  #else
  27  static int power_off = 1;
  28  #endif
  29 @@ -1797,6 +1798,14 @@ static int apm(void *unused)
  30                 }
  31         }
  32
  33 +#ifdef CONFIG_SMP
  34 +       if (!power_off_set) {
  35 +               power_off = (num_online_cpus() == 1);
  36 +               /* remember not to initialize (with default value) again */
  37 +               power_off_set = 1;
  38 +       }
  39 +#endif
  40 +
  41         /* Install our power off handler.. */
  42         if (power_off)
  43                 pm_power_off = apm_power_off;
  44 @@ -1840,8 +1849,12 @@ static int __init apm_setup(char *str)
  45                 if (strncmp(str, "debug", 5) == 0)
  46                         debug = !invert;
  47                 if ((strncmp(str, "power-off", 9) == 0) ||
  48 -                   (strncmp(str, "power_off", 9) == 0))
  49 +                   (strncmp(str, "power_off", 9) == 0)) {
  50                         power_off = !invert;
  51 +#ifdef CONFIG_SMP
  52 +                       power_off_set = 1;
  53 +#endif
  54 +               }
  55                 if (strncmp(str, "smp", 3) == 0) {
  56                         smp = !invert;
  57                         idle_threshold = 100;