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Subject[tip:perf/core] perf report: Fix wrong jump arrow
Commit-ID:  b40982e8468b46b8f7f5bba5a7e541ec04a29d7d
Gitweb: https://git.kernel.org/tip/b40982e8468b46b8f7f5bba5a7e541ec04a29d7d
Author: Jin Yao <yao.jin@linux.intel.com>
AuthorDate: Mon, 29 Jan 2018 18:57:53 +0800
Committer: Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Fri, 16 Feb 2018 14:55:47 -0300

perf report: Fix wrong jump arrow

When we use perf report interactive annotate view, we can see
the position of jump arrow is not correct. For example,

1. perf record -b ...
2. perf report
3. In interactive mode, select Annotate 'function'

Percent│ IPC Cycle
│ if (flag)
1.37 │0.4┌── 1 ↓ je 82
│ │ x += x / y + y / x;
0.00 │0.4│ 1310 movsd (%rsp),%xmm0
0.00 │0.4│ 565 movsd 0x8(%rsp),%xmm4
│0.4│ movsd 0x8(%rsp),%xmm1
│0.4│ movsd (%rsp),%xmm3
│0.4│ divsd %xmm4,%xmm0
0.00 │0.4│ 579 divsd %xmm3,%xmm1
│0.4│ movsd (%rsp),%xmm2
│0.4│ addsd %xmm1,%xmm0
│0.4│ addsd %xmm2,%xmm0
0.00 │0.4│ movsd %xmm0,(%rsp)
│ │ volatile double x = 1212121212, y = 121212;
│ │
│ │ s_randseed = time(0);
│ │ srand(s_randseed);
│ │
│ │ for (i = 0; i < 2000000000; i++) {
1.37 │0.4└─→ 82: sub $0x1,%ebx
28.21 │0.48 17 ↑ jne 38

The jump arrow in above example is not correct. It should add the
width of IPC and Cycle.

With this patch, the result is:

Percent│ IPC Cycle
│ if (flag)
1.37 │0.48 1 ┌──je 82
│ │ x += x / y + y / x;
0.00 │0.48 1310 │ movsd (%rsp),%xmm0
0.00 │0.48 565 │ movsd 0x8(%rsp),%xmm4
│0.48 │ movsd 0x8(%rsp),%xmm1
│0.48 │ movsd (%rsp),%xmm3
│0.48 │ divsd %xmm4,%xmm0
0.00 │0.48 579 │ divsd %xmm3,%xmm1
│0.48 │ movsd (%rsp),%xmm2
│0.48 │ addsd %xmm1,%xmm0
│0.48 │ addsd %xmm2,%xmm0
0.00 │0.48 │ movsd %xmm0,(%rsp)
│ │ volatile double x = 1212121212, y = 121212;
│ │
│ │ s_randseed = time(0);
│ │ srand(s_randseed);
│ │
│ │ for (i = 0; i < 2000000000; i++) {
1.37 │0.48 82:└─→sub $0x1,%ebx
28.21 │0.48 17 ↑ jne 38

Committer notes:

Please note that only from LBRv5 (according to Jiri) onwards, i.e. >=
Skylake is that we'll have the cycles counts in each branch record
entry, so to see the Cycles and IPC columns, and be able to test this
patch, one need a capable hardware.

While applying this I first tested it on a Broadwell class machine and
couldn't get those columns, will add code to the annotate browser to
warn the user about that, i.e. you have branch records, but no cycles,
use a more recent hardware to get the cycles and IPC columns.

Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1517223473-14750-1-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/ui/browsers/annotate.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/tools/perf/ui/browsers/annotate.c b/tools/perf/ui/browsers/annotate.c
index 2864279..e2f6663 100644
--- a/tools/perf/ui/browsers/annotate.c
+++ b/tools/perf/ui/browsers/annotate.c
@@ -319,6 +319,7 @@ static void annotate_browser__draw_current_jump(struct ui_browser *browser)
struct map_symbol *ms = ab->b.priv;
struct symbol *sym = ms->sym;
u8 pcnt_width = annotate_browser__pcnt_width(ab);
+ int width = 0;

/* PLT symbols contain external offsets */
if (strstr(sym->name, "@plt"))
@@ -340,13 +341,17 @@ static void annotate_browser__draw_current_jump(struct ui_browser *browser)
to = (u64)btarget->idx;
}

+ if (ab->have_cycles)
+ width = IPC_WIDTH + CYCLES_WIDTH;
+
ui_browser__set_color(browser, HE_COLORSET_JUMP_ARROWS);
- __ui_browser__line_arrow(browser, pcnt_width + 2 + ab->addr_width,
+ __ui_browser__line_arrow(browser,
+ pcnt_width + 2 + ab->addr_width + width,
from, to);

if (is_fused(ab, cursor)) {
ui_browser__mark_fused(browser,
- pcnt_width + 3 + ab->addr_width,
+ pcnt_width + 3 + ab->addr_width + width,
from - 1,
to > from ? true : false);
}
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