perf tools: Warn while running perf trace without sample

When a user runs perf trace using an input with logged
counters without PERF_SAMPLE_RAW attribute, warn by giving a
nice tip.

Signed-off-by: Frederic Weisbecker <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Steven Rostedt <[email protected]>
LKML-Reference: <1250543271[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>

diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index b160a9f61bf3ba39f69e677952b29203df45e901..88eef71bce6d63f7fd8d338e6979f58b0901d5ec 100644 (file)
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -184,6 +184,10 @@ static int __cmd_trace(void)
        header = perf_header__read(input);
        sample_type = perf_header__sample_type(header);
 
+       if (!(sample_type & PERF_SAMPLE_RAW))
+               die("No trace sample to read. Did you call perf record "
+                   "without -R?");
+
        if (load_kernel() < 0) {
                perror("failed to load kernel symbols");
                return EXIT_FAILURE;