perf probe: Fix concat_probe_trace_events

[ Upstream commit f0a30dca5f84fe8048271799b56677ac2279de66 ]

'*ntevs' contains number of elements present in 'tevs' array. If there
are no elements in array, 'tevs2' can be directly assigned to 'tevs'
without allocating more space. So the condition should be  '*ntevs == 0'
not  'ntevs == 0'.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: 42bba263eb58 ("perf probe: Allow wildcard for cached events")
Link: http://lkml.kernel.org/r/20170308065908.4128-1-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 6a6f44d..4d2e22f 100644 (file)
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -3060,7 +3060,7 @@ concat_probe_trace_events(struct probe_trace_event **tevs, int *ntevs,
        struct probe_trace_event *new_tevs;
        int ret = 0;
 
-       if (ntevs == 0) {
+       if (*ntevs == 0) {
                *tevs = *tevs2;
                *ntevs = ntevs2;
                *tevs2 = NULL;