Re: [PATCH v4 0/5] perf report: Show branch type

From: Jin, Yao
Date: Wed Apr 12 2017 - 23:26:03 EST



On 4/13/2017 10:00 AM, Jin, Yao wrote:


On 4/12/2017 6:58 PM, Jiri Olsa wrote:
On Wed, Apr 12, 2017 at 06:21:01AM +0800, Jin Yao wrote:

SNIP

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



I have tested, the regression issue is happened after this commit:

bdd97ca perf tools: Refactor the code to strip command name with {l,r}trim()

CC to the author for double checking.

Thanks
Jin Yao