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Subject[PATCH -tip v5 0/5] perf script: add BTS analysis features
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Hi Frederic, David,

This patch series adds the functions to analyze BTS logs to perf-script and,
makes perf-script more informative version 5.
The patches add the following functions.
- Unify the expression to "[unknown]"
- Fix BTS record header to resolve DSOs and symbols of user-space
- Resolve DSOs and symbols for BTS's branch_from addresses
- Show the offset of symbols with the 'symoff' field specifier.
- Resolve the real path of [kernel.kallsym] using
'--show-kernel-path' option.

Usage:
First, get the BTS log with the following command.
# perf record -e branches:u -c 1 -d <command>

Second, analyze that trace data.
# perf script -f ip,addr,sym,symoff,dso [--show-kernel-path]
This command's output format is:
<branch_from addr> <branch_from function+offset> <branch_from DSO> => <branch_to addr> <branch_to function+offset> <branch_to DSO>

Output sample:
# perf record -e branches:u -c 1 -d ls
[snip]
# perf script -f ip,addr,sym,dso,symoff --show-kernel-path
[snip]
3430c21399 __libc_start_main+0xe9 (/lib64/libc-2.14.so) => 402c1c main+0x0 (/root/bin/ls)
402c41 main+0x25 (/root/bin/ls) => 40b390 set_program_name+0x0 (/root/bin/ls)
ffffffff814ac5ed irq_return+0x0 (/lib/modules/3.2.0+/build/vmlinux) => 40b390 set_program_name+0x0 (/root/bin/ls)
40b39e set_program_name+0xe (/root/bin/ls) => 401e20 strrchr@plt+0x0 (/root/bin/ls)
401e20 strrchr@plt+0x0 (/root/bin/ls) => 401e26 strrchr@plt+0x6 (/root/bin/ls)
401e2b strrchr@plt+0xb (/root/bin/ls) => 401b80 _init+0x18 (/root/bin/ls)
401b86 _init+0x1e (/root/bin/ls) => 3430813850 _dl_runtime_resolve+0x0 (/lib64/ld-2.14.so)
[snip]

It shows the tracee application's execution path.


Future Works:
- add source code path field, line number field ...etc.
- add record/report script to use easily and, show human-friendly output.
- filtering kernel functions using scripts

Changes in v5:
- Use fprintf() instead of printf() in struct map/symbol's functions
to print something.
- Abolish using 'self' in function's paramater
e.g. map__print_dsoname(self) => map__fprintf_dsoname(map, fp)
- Change the specifier to print symbol_offset 'offs' to 'symoff'
- Change the output format "<branch_to> <branch_from>" to
"<branch_from> => <branch_to>"

Changes in v4:
- add check routine to set correct perf_sample's header.

Changes in v3:
- remove the bug fix patch already fixed.
- unify the "[unknown]" expressions in perf-script.
- fix perf_event_header of BTS events.
- fix patch's descriptions

Changes in v2:
- add a bug fix patch that prints correct IP address
- output the magic word "(unknown)" as symbol name when perf-script can't
resolve symbols.
- output "[unknown]" as DSO name when perf-script can't resolve DSO path.
- change the way to output offset of symbols from '--show-symbol-offset' to
'offs' field.
- clean up codes.

Thanks,

---

Akihiro Nagai (5):
perf script: add option resolving vmlinux path
perf script: add the offset field specifier
perf script: print branch_from and branch_to of BTS events
perf: set correct value to perf_event_header.misc for BTS
perf-script: unify the expressions indicate "unknown"


arch/x86/kernel/cpu/perf_event_intel_ds.c | 31 +++++++----
tools/perf/Documentation/perf-script.txt | 5 +-
tools/perf/builtin-script.c | 80 ++++++++++++++++++++++++-----
tools/perf/util/map.c | 15 +++++
tools/perf/util/map.h | 1
tools/perf/util/session.c | 39 +++++---------
tools/perf/util/session.h | 2 -
tools/perf/util/symbol.c | 22 ++++++++
tools/perf/util/symbol.h | 4 +
9 files changed, 147 insertions(+), 52 deletions(-)

--
Akihiro Nagai (akihiro.nagai.hw@hitachi.com)


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