perf hists browser: Fix event group display
commit d9ea48bc 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 <milian.wolff@kdab.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Fixes: 89fee709 ("perf hists: Do column alignment on the format iterator") Link: http://lkml.kernel.org/r/20160912061958.16656-2-namhyung@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Showing
Please register or sign in to comment