[PATCH v3 1/6] perf cs-etm: Fix unsigned variable comparison to zero

Leo Yan
2019-10-05T09:17:06Z

If the u64 variable 'offset' is a negative integer, comparison it with
bigger than zero is always going to be true because it is unsigned.
Fix this by using s64 type for variable 'offset'.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
---
tools/perf/util/cs-etm.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index 4ba0f871f086..4bc2d9709d4f 100644
--- a/tools/perf/util/cs-etm.c
+++ b/tools/perf/util/cs-etm.c
@@ -940,7 +940,7 @@ u64 cs_etm__last_executed_instr(const struct cs_etm_packet *packet)
static inline u64 cs_etm__instr_addr(struct cs_etm_queue *etmq,
u64 trace_chan_id,
const struct cs_etm_packet *packet,
- u64 offset)
+ s64 offset)
{
if (packet->isa == CS_ETM_ISA_T32) {
u64 addr = packet->start_addr;
@@ -1372,7 +1372,7 @@ static int cs_etm__sample(struct cs_etm_queue *etmq,
* sample is reported as though instruction has just been
* executed, but PC has not advanced to next instruction)
*/
- u64 offset = (instrs_executed - instrs_over - 1);
+ s64 offset = (instrs_executed - instrs_over - 1);
u64 addr = cs_etm__instr_addr(etmq, trace_chan_id,
tidq->packet, offset);

--
2.17.1