The mmap_pages default value is not power of 2 (UINT_MAX).

Together with perf_evlist__mmap function returning error value
different from EPERM, we get misleading error message:
"--mmap_pages/-m value must be a power of two."

Fixing this by adding extra check for UINT_MAX value for this
error condition.

Signed-off-by: Jiri Olsa <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Corey Ashford <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: Namhyung Kim <[email protected]>
---
 tools/perf/builtin-record.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 3cf7fe2..93dc67e 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -358,7 +358,8 @@ try_again:
                               "or try again with a smaller value of 
-m/--mmap_pages.\n"
                               "(current value: %d)\n", opts->mmap_pages);
                        rc = -errno;
-               } else if (!is_power_of_2(opts->mmap_pages)) {
+               } else if (!is_power_of_2(opts->mmap_pages) &&
+                          (opts->mmap_pages != UINT_MAX)) {
                        pr_err("--mmap_pages/-m value must be a power of two.");
                        rc = -EINVAL;
                } else {
-- 
1.7.11.4

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