On 4/12/2017 6:58 PM, Jiri Olsa wrote:

On Wed, Apr 12, 2017 at 06:21:01AM +0800, Jin Yao wrote:

SNIP

quoted

3. Use 2 bits in perf_branch_entry for a "cross" metrics checking
    for branch cross 4K or 2M area. It's an approximate computing
    for checking if the branch cross 4K page or 2MB page.

For example:

perf record -g --branch-filter any,save_type <command>

perf report --stdio

      JCC forward:  27.7%
     JCC backward:   9.8%
              JMP:   0.0%
          IND_JMP:   6.5%
             CALL:  26.6%
         IND_CALL:   0.0%
              RET:  29.3%
             IRET:   0.0%
         CROSS_4K:   0.0%
         CROSS_2M:  14.3%

got mangled perf report --stdio output for:


[root@ibm-x3650m4-02 perf]# ./perf record -j any,save_type kill
kill: not enough arguments
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.013 MB perf.data (18 samples) ]

[root@ibm-x3650m4-02 perf]# ./perf report --stdio -f | head -30
# To display the perf.data header info, please use --header/--header-only options.
#
#
# Total Lost Samples: 0
#
# Samples: 253  of event 'cycles'
# Event count (approx.): 253
#
# Overhead  Command  Source Shared Object  Source Symbol                            Target Symbol                            Basic Block Cycles
# ........  .......  ....................  .......................................  .......................................  ..................
#
      8.30%  perf
Um  [kernel.vmlinux]      [k] __intel_pmu_enable_all.constprop.17  [k] native_write_msr                     -
      7.91%  perf
Um  [kernel.vmlinux]      [k] intel_pmu_lbr_enable_all             [k] __intel_pmu_enable_all.constprop.17  -
      7.91%  perf
Um  [kernel.vmlinux]      [k] native_write_msr                     [k] intel_pmu_lbr_enable_all             -
      6.32%  kill     libc-2.24.so          [.] _dl_addr                             [.] _dl_addr                             -
      5.93%  perf
Um  [kernel.vmlinux]      [k] perf_iterate_ctx                     [k] perf_iterate_ctx                     -
      2.77%  kill     libc-2.24.so          [.] malloc                               [.] malloc                               -
      1.98%  kill     libc-2.24.so          [.] _int_malloc                          [.] _int_malloc                          -
      1.58%  kill     [kernel.vmlinux]      [k] __rb_insert_augmented                [k] __rb_insert_augmented                -
      1.58%  perf
Um  [kernel.vmlinux]      [k] perf_event_exec                      [k] perf_event_exec                      -
      1.19%  kill     [kernel.vmlinux]      [k] anon_vma_interval_tree_insert        [k] anon_vma_interval_tree_insert        -
      1.19%  kill     [kernel.vmlinux]      [k] free_pgd_range                       [k] free_pgd_range                       -
      1.19%  kill     [kernel.vmlinux]      [k] n_tty_write                          [k] n_tty_write                          -
      1.19%  perf
Um  [kernel.vmlinux]      [k] native_sched_clock                   [k] sched_clock                          -
...
SNIP


jirka

Sorry, I look at this issue at midnight in Shanghai. I misunderstood 
that the above output was only a mail format issue. Sorry about that.

Now I recheck the output, and yes, the perf report output is mangled. 
But my patch doesn't touch the associated code.

Anyway I remove my patches, pull the latest update from perf/core branch 
and run tests to check if its a regression issue. I test on HSW and SKL 
both.

1. On HSW.

root@hsw:/tmp# perf record -j any kill
...... /* SNIP */
For more details see kill(1).
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.014 MB perf.data (9 samples) ]

root@hsw:/tmp# perf report --stdio
# To display the perf.data header info, please use 
--header/--header-only options.
#
#
# Total Lost Samples: 0
#
# Samples: 144  of event 'cycles'
# Event count (approx.): 144
#
# Overhead  Command  Source Shared Object  Source 
Symbol                    Target Symbol                    Basic Block 
Cycles
# ........  .......  .................... 
...............................  ............................... 
..................
#
     10.42%  kill     libc-2.23.so          [.] 
read_alias_file              [.] read_alias_file              -
      9.72%  kill     [kernel.vmlinux]      [k] 
update_load_avg              [k] update_load_avg              -
      9.03%  perf
Um  [unknown]             [k] 0000000000000000             [k] 
0000000000000000             -
      8.33%  kill     libc-2.23.so          [.] 
_int_malloc                  [.] _int_malloc                  -
...... /* SNIP */
      0.69%  kill     [kernel.vmlinux]      [k] 
_raw_spin_lock               [k] unmap_page_range             -
      0.69%  perf
Um  [kernel.vmlinux]      [k] __intel_pmu_enable_all       [k] 
native_write_msr             -
      0.69%  perf
Um  [kernel.vmlinux]      [k] intel_pmu_lbr_enable_all     [k] 
__intel_pmu_enable_all       -
      0.69%  perf
Um  [kernel.vmlinux]      [k] native_write_msr             [k] 
intel_pmu_lbr_enable_all     -

The issue is still there.

2. On SKL

root@skl:/tmp# perf record -j any kill
...... /* SNIP */
For more details see kill(1).
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.012 MB perf.data (1 samples) ]

root@skl:/tmp# perf report --stdio

# To display the perf.data header info, please use 
--header/--header-only options.
#
#
# Total Lost Samples: 0
#
# Samples: 32  of event 'cycles'
# Event count (approx.): 32
#
# Overhead  Command  Source Shared Object  Source Symbol                 
Target Symbol                 Basic Block Cycles
# ........  .......  .................... ............................  
............................ ..................
#
     90.62%  perf
Um  [unknown]             [k] 0000000000000000          [k] 
0000000000000000          -
      3.12%  perf
Um  [kernel.vmlinux]      [k] __intel_pmu_enable_all    [k] 
native_write_msr          11
      3.12%  perf
Um  [kernel.vmlinux]      [k] intel_pmu_lbr_enable_all  [k] 
__intel_pmu_enable_all    4
      3.12%  perf
Um  [kernel.vmlinux]      [k] native_write_msr          [k] 
intel_pmu_lbr_enable_all  -

The issue is there too.

Now it works without my patch and it runs with latest perf/core branch. 
So it looks like a regression issue.

Thanks
Jin Yao