perf tools: Just pr_debug() about not being able to read cacheline_size

So far the cacheline_size is only useful for the "dcacheline" --sort
order, i.e. if that is not used, which is the norm, then the user
shouldn't care that he is running this, say, on an Android system where
sysconf(_SC_LEVEL1_DCACHE_LINESIZE) and the
/sys/devices/system/cpu/cpu0/cache/index0/coherency_line_size sysfs file
isn't available.

An upcoming patch will emit an warning only for "--sort ...,dcacheline,...".

Cc: Adrian Hunter <[email protected]>
Cc: Chris Phlipot <[email protected]>
Cc: David Ahern <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Wang Nan <[email protected]>
Link: http://lkml.kernel.org/n/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

diff --git a/tools/perf/perf.c b/tools/perf/perf.c
index 4b2ff021434c29a35450d03c4c610a59c319884e..64c06961bfe495341c954ffced4aa5e06d5e380e 100644 (file)
--- a/tools/perf/perf.c
+++ b/tools/perf/perf.c
@@ -503,7 +503,7 @@ void pthread__unblock_sigwinch(void)
 static void cache_line_size(int *cacheline_sizep)
 {
        if (sysfs__read_int("devices/system/cpu/cpu0/cache/index0/coherency_line_size", cacheline_sizep))
-               perror("cannot determine cache line size");
+               pr_debug("cannot determine cache line size");
 }
 #endif