tree 73ba840aa9a401befd3425d1eba0d7b63a81f851
parent d4ae0a6f7c79be64c8f3551dd149189f8c4480eb
author Runzhen Wang <runzhen@linux.vnet.ibm.com> 1372407297 +0800
committer Arnaldo Carvalho de Melo <acme@redhat.com> 1373647569 -0300

perf tools: Make Power7 events available for perf

Power7 supports over 530 different perf events but only a small subset
of these can be specified by name, for the remaining events, we must
specify them by their raw code:

        perf stat -e r2003c <application>

This patch makes all the POWER7 events available in sysfs.  So we can
instead specify these as:

        perf stat -e 'cpu/PM_CMPLU_STALL_DFU/' <application>

where PM_CMPLU_STALL_DFU is the r2003c in previous example.

Before this patch is applied, the size of power7-pmu.o is:

$ size arch/powerpc/perf/power7-pmu.o
   text	   data	    bss	    dec	    hex	filename
   3073	   2720	      0	   5793	   16a1	arch/powerpc/perf/power7-pmu.o

and after the patch is applied, it is:

$ size arch/powerpc/perf/power7-pmu.o
   text	   data	    bss	    dec	    hex	filename
  15950	  31112	      0	  47062	   b7d6	arch/powerpc/perf/power7-pmu.o

For the run time overhead, I use two scripts, one is "event_name.sh",
which contains 50 event names, it looks like:

 # ./perf record  -e 'cpu/PM_CMPLU_STALL_DFU/' -e .....  /bin/sleep 1

the other one is named "event_code.sh" which use corresponding  events
raw
code instead of events names, it looks like:

 # ./perf record -e r2003c -e ......  /bin/sleep 1

below is the result.

Using events name:

[root@localhost perf]# time ./event_name.sh
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.002 MB perf.data (~102 samples) ]

real	0m1.192s
user	0m0.028s
sys	0m0.106s

Using events raw code:

[root@localhost perf]# time ./event_code.sh
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.003 MB perf.data (~112 samples) ]

real	0m1.198s
user	0m0.028s
sys	0m0.105s

Signed-off-by: Runzhen Wang <runzhen@linux.vnet.ibm.com>
Acked-by: Michael Ellerman <michael@ellerman.id.au>
Cc: icycoder@gmail.com
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Runzhen Wang <runzhew@clemson.edu>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1372407297-6996-3-git-send-email-runzhen@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>