[PATCH 0/5] powerpc, perf: BHRB based branch stack enablement on POWER8

Anshuman Khandual khandual at linux.vnet.ibm.com
Tue Apr 16 22:56:35 EST 2013


		Branch History Rolling Buffer (BHRB) is a new PMU feaure in IBM
POWER8 processor which records the branch instructions inside the execution
pipeline. This patchset enables the basic functionality of the feature through
generic perf branch stack sampling framework.

Sample output
-------------
$./perf record -b top
$./perf report

Overhead  Command  Source Shared Object                           Source Symbol  Target Shared Object                        Target Symbol
# ........  .......  ....................  ......................................  ....................  ...................................
#

     7.82%      top  libc-2.11.2.so        [k] _IO_vfscanf                         libc-2.11.2.so        [k] _IO_vfscanf                    
     6.17%      top  libc-2.11.2.so        [k] _IO_vfscanf                         [unknown]             [k] 00000000                       
     2.37%      top  [unknown]             [k] 0xf7aafb30                          [unknown]             [k] 00000000                       
     1.80%      top  [unknown]             [k] 0x0fe07978                          libc-2.11.2.so        [k] _IO_vfscanf                    
     1.60%      top  libc-2.11.2.so        [k] _IO_vfscanf                         [kernel.kallsyms]     [k] .do_task_stat                  
     1.20%      top  [kernel.kallsyms]     [k] .do_task_stat                       [kernel.kallsyms]     [k] .do_task_stat                  
     1.02%      top  libc-2.11.2.so        [k] vfprintf                            libc-2.11.2.so        [k] vfprintf                       
     0.92%      top  top                   [k] _init                               [unknown]             [k] 0x0fe037f4                     

Anshuman Khandual (5):
  powerpc, perf: Add new BHRB related instructions on POWER8
  powerpc, perf: Add basic assembly code to read BHRB entries on POWER8
  powerpc, perf: Add new BHRB related generic functions, data and flags
  powerpc, perf: Define BHRB generic functions, data and flags for POWER8
  powerpc, perf: Enable branch stack sampling framework support with BHRB

 arch/powerpc/include/asm/perf_event_server.h |  6 ++
 arch/powerpc/include/asm/ppc-opcode.h        |  7 ++
 arch/powerpc/perf/Makefile                   |  2 +-
 arch/powerpc/perf/bhrb.S                     | 34 ++++++++++
 arch/powerpc/perf/core-book3s.c              | 96 +++++++++++++++++++++++++++-
 arch/powerpc/perf/perf_event_bhrb.c          | 75 ++++++++++++++++++++++
 arch/powerpc/perf/power8-pmu.c               | 57 ++++++++++++++++-
 7 files changed, 272 insertions(+), 5 deletions(-)
 create mode 100644 arch/powerpc/perf/bhrb.S
 create mode 100644 arch/powerpc/perf/perf_event_bhrb.c

-- 
1.7.11.7



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