src/patches/suse-2.6.27.31/patches.arch/s390-09-04-topology.diff

   1 From: Gerald Schaefer <geraldsc@de.ibm.com>
   2 Subject: topology: introduce arch specific SD_MC_INIT initializer
   3 References: bnc#477666,LTC#51049
   4
   5 Symptom:     Up to 30% more cpu usage for some workloads.
   6 Problem:     For some workloads the extra multicore scheduling domain causes
   7              additional cpu usage because of too optimistic assumptions when
   8              it is ok to migrate processes from one cpu to another. The default
   9              values for SD_MC_INIT don't work well on s390.
  10 Solution:    Define an architecure specific SD_MC_INIT scheduling domain
  11              initializer which fixes the regression.
  12
  13 Acked-by: John Jolly <jjolly@suse.de>
  14 ---
  15  arch/s390/include/asm/topology.h |    2 ++
  16  1 file changed, 2 insertions(+)
  17
  18 Index: linux-sles11/arch/s390/include/asm/topology.h
  19 ===================================================================
  20 --- linux-sles11.orig/arch/s390/include/asm/topology.h
  21 +++ linux-sles11/arch/s390/include/asm/topology.h
  22 @@ -28,6 +28,8 @@ static inline void s390_init_cpu_topolog
  23  };
  24  #endif
  25
  26 +#define SD_MC_INIT SD_CPU_INIT
  27 +
  28  #include <asm-generic/topology.h>
  29
  30  #endif /* _ASM_S390_TOPOLOGY_H */