[PATCH 19/19] perf report: Fix branch stack mode cannot be set

From: Arnaldo Carvalho de Melo
Date: Fri Feb 27 2015 - 14:24:54 EST


From: He Kuang <hekuang@xxxxxxxxxx>

When perf.data file is obtained using 'perf record -b', perf report
should use branch stack mode to generate output. But this function is
broken by improper comparison between boolean and constant -1.

before this patch:

$ perf report -b -i perf.data
Samples: 16 of event 'cycles', Event count (approx.): 3171896
Overhead Command Shared Object Symbol
13.59% ls [kernel.kallsyms] [k] prio_tree_remove
13.16% ls [kernel.kallsyms] [k] change_pte_range
12.09% ls [kernel.kallsyms] [k] page_fault
12.02% ls [kernel.kallsyms] [k] zap_pte_range
...

after this patch:

$ perf report -b -i perf.data
Samples: 256 of event 'cycles', Event count (approx.): 256
Overhead Command Source Shared Object Source Symbol Target Shared Object Target Symbol
9.38% ls [unknown] [k] 0000000000000000 [unknown] [k] 0000000000000000
6.25% ls libc-2.19.so [.] _dl_addr libc-2.19.so [.] _dl_addr
6.25% ls [kernel.kallsyms] [k] zap_pte_range [kernel.kallsyms] [k] zap_pte_range
6.25% ls [kernel.kallsyms] [k] change_pte_range [kernel.kallsyms] [k] change_pte_range
0.39% ls [kernel.kallsyms] [k] prio_tree_remove [kernel.kallsyms] [k] prio_tree_remove
...

Signed-off-by: He Kuang <hekuang@xxxxxxxxxx>
Tested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Wang Nan <wangnan0@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/1423967617-28879-1-git-send-email-hekuang@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/builtin-report.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 0ba5f07906fb..fb350343b1d7 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -768,7 +768,7 @@ repeat:
* 0/1 means the user chose a mode.
*/
if (((branch_mode == -1 && has_br_stack) || branch_mode == 1) &&
- branch_call_mode == -1) {
+ !branch_call_mode) {
sort__mode = SORT_MODE__BRANCH;
symbol_conf.cumulate_callchain = false;
}
--
1.9.3

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