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Date: Tue, 25 Sep 2012 13:57:26 +0900
From: Namhyung Kim <namhyung@...nel.org>
To: Arnaldo Carvalho de Melo <acme@...stprotocols.net>,
Arun Sharma <asharma@...com>
Cc: Peter Zijlstra <a.p.zijlstra@...llo.nl>,
Paul Mackerras <paulus@...ba.org>,
Ingo Molnar <mingo@...nel.org>,
LKML <linux-kernel@...r.kernel.org>,
Frederic Weisbecker <fweisbec@...il.com>,
David Ahern <dsahern@...il.com>, Jiri Olsa <jolsa@...hat.com>
Subject: Re: [RFC/PATCHSET 00/15] perf report: Add support to accumulate hist periods
Ping. Any comments for this?
Arun, thanks for testing!
Namhyung
On Thu, 13 Sep 2012 16:19:56 +0900, Namhyung Kim wrote:
> Hi,
>
> This is my first attempt to implement cumulative hist period report.
> This work begins from Arun's SORT_INCLUSIVE patch [1] but I completely
> rewrote it from scratch.
>
> It basically adds period in a sample to every node in the callchain.
> A hist_entry now has an additional fields to keep the cumulative
> period if --cumulate option is given on perf report.
>
> Let me show you an example:
>
> $ cat abc.c
> #define barrier() asm volatile("" ::: "memory")
>
> void a(void)
> {
> int i;
>
> for (i = 0; i < 1000000; i++)
> barrier();
> }
>
> void b(void)
> {
> a();
> }
>
> void c(void)
> {
> b();
> }
>
> int main(void)
> {
> c();
>
> return 0;
> }
>
> With this simple program I ran perf record and report:
>
> $ perf record -g -e cycles:u ./abc
> $ perf report -g none --stdio
> [snip]
> # Overhead Command Shared Object Symbol
> # ........ ....... .................. ..........................
> #
> 93.35% abc abc [.] a
> 5.17% abc ld-2.15.so [.] _dl_map_object_from_fd
> 1.13% abc ld-2.15.so [.] _dl_start
> 0.29% abc libpthread-2.15.so [.] __libc_close
> 0.07% abc [kernel.kallsyms] [k] page_fault
> 0.00% abc ld-2.15.so [.] _start
>
> When --cumulate option is given, it'll be shown like this:
>
> $ perf report --cumulate
> (...)
> + 93.63% abc libc-2.15.so [.] __libc_start_main
> + 93.35% abc abc [.] main
> + 93.35% abc abc [.] c
> + 93.35% abc abc [.] b
> + 93.35% abc abc [.] a
> + 5.17% abc ld-2.15.so [.] _dl_map_object
> + 5.17% abc ld-2.15.so [.] _dl_map_object_from_fd
> + 1.13% abc ld-2.15.so [.] _dl_start_user
> + 1.13% abc ld-2.15.so [.] _dl_start
> + 0.29% abc perf [.] main
> + 0.29% abc perf [.] run_builtin
> + 0.29% abc perf [.] cmd_record
> + 0.29% abc libpthread-2.15.so [.] __libc_close
> + 0.07% abc ld-2.15.so [.] _start
> + 0.07% abc [kernel.kallsyms] [k] page_fault
>
> (This output came from TUI since stdio bothered by callchains)
>
> As you can see __libc_start_main -> main -> c -> b -> a callchain show
> up in the output.
>
> It might have some rough edges or even bugs, but I really want to
> release it and get reviews. In fact I saw some very large percentage
> or 'inf' on some callchain nodes when expanding.
>
> It currently ignores samples don't have symbol info when accumulating
> periods along the callchain. Otherwise it resulted in very strangely
> large output since every node in the callchain would be added into a
> single entry which has NULL dso/sym. Simply ignoring them solved the
> problem and I couldn't come up with a better solution.
>
> This patchset is based on current acme/perf/core + my small fixes [2],[3].
> You can also get this series on my tree at:
>
> git://git.kernel.org/pub/scm/linux/kernel/git/namhyung/linux-perf.git perf/cumulate-v1
>
> Any comments are welcome, thanks.
> Namhyung
>
> [1] https://lkml.org/lkml/2012/3/31/6
> [2] https://lkml.org/lkml/2012/9/11/546
> [3] https://lkml.org/lkml/2012/9/12/51
>
>
> Namhyung Kim (15):
> perf hists: Add missing period_* fields when collapsing a hist entry
> perf hists: Introduce struct he_stat
> perf hists: Move he->stat.nr_events initialization to a template
> perf hists: Convert hist entry functions to use struct he_stat
> perf hists: Add more helpers for hist entry stat
> perf hists: Add support for accumulated stat of hist entry
> perf hists: Check if accumulated when adding a hist entry
> perf callchain: Add a couple of callchain helpers
> perf hists: Let add_hist_entry to make a hist entry template
> perf hists: Accumulate hist entry stat based on the callchain
> perf hists: Sort hist entries by accumulated period
> perf ui/hist: Add support to accumulated hist stat
> perf ui/browser: Add support to accumulated hist stat
> perf ui/gtk: Add support to accumulated hist stat
> perf report: Add --cumulate option
>
> tools/perf/builtin-report.c | 8 ++
> tools/perf/ui/browsers/hists.c | 12 +-
> tools/perf/ui/gtk/browser.c | 5 +-
> tools/perf/ui/hist.c | 74 ++++++++++---
> tools/perf/ui/stdio/hist.c | 2 +-
> tools/perf/util/callchain.c | 15 +++
> tools/perf/util/callchain.h | 17 +++
> tools/perf/util/hist.c | 242 +++++++++++++++++++++++++++++++++--------
> tools/perf/util/sort.h | 17 ++-
> tools/perf/util/symbol.h | 1 +
> 10 files changed, 318 insertions(+), 75 deletions(-)
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