[PATCH 4.8 094/125] perf hists browser: Fix event group display
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2016-10-29 14:05:45
Also in:
lkml
4.8-stable review patch. If anyone has any objections, please let me know.
------------------
From: Namhyung Kim <namhyung@kernel.org>
commit d9ea48bc4e7cc297ca1073fa3f90ed80d964b7b4 upstream.
Milian reported that the event group on TUI shows duplicated overhead.
This was due to a bug on calculating hpp->buf position. The
hpp_advance() was called from __hpp__slsmg_color_printf() on TUI but
it's already called from the hpp__call_print_fn macro in __hpp__fmt().
The end result is that the print function returns number of bytes it
printed but the buffer advanced twice of the length.
This is generally not a problem since it doesn't need to access the
buffer again. But with event group, overhead needs to be printed
multiple times and hist_entry__snprintf_alignment() tries to fill the
space with buffer after it printed. So it (brokenly) showed the last
overhead again.
The bug was there from the beginning, but I think it's only revealed
when the alignment function was added.
Reported-by: Milian Wolff <redacted>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Andi Kleen <redacted>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <redacted>
Fixes: 89fee7094323 ("perf hists: Do column alignment on the format iterator")
Link: http://lkml.kernel.org/r/20160912061958.16656-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <redacted>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
tools/perf/ui/browsers/hists.c | 1 -
1 file changed, 1 deletion(-)
--- a/tools/perf/ui/browsers/hists.c
+++ b/tools/perf/ui/browsers/hists.c@@ -1091,7 +1091,6 @@ static int __hpp__slsmg_color_printf(str ret = scnprintf(hpp->buf, hpp->size, fmt, len, percent); ui_browser__printf(arg->b, "%s", hpp->buf); - advance_hpp(hpp, ret); return ret; }