Em Wed, Apr 22, 2020 at 05:44:02PM +0300, Alexey Budankov escreveu: > > Update error message to mention CAP_PERFMON only. CAP_SYS_ADMIN still > works in keeping with user space backward compatibility approach. This will confuse users that build the latest perf to use in older systems where CAP_PERFMON isn't available, probably we need to, in these cases, check for the existence of CAP_PERFMON to provide a better warning message, something like: You need CAP_ADMIN or update your kernel and libcap to one that supports CAP_PERFMON. For systems without CAP_PERFMON, while mentioning only CAP_PERFMON for systems where it is present, right? > Signed-off-by: Alexey Budankov <alexey.budankov@xxxxxxxxxxxxxxx> > --- > tools/perf/builtin-ftrace.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c > index 55eda54240fb..39d43ad02f30 100644 > --- a/tools/perf/builtin-ftrace.c > +++ b/tools/perf/builtin-ftrace.c > @@ -288,7 +288,7 @@ static int __cmd_ftrace(struct perf_ftrace *ftrace, int argc, const char **argv) > perf_cap__capable(CAP_SYS_ADMIN))) { > pr_err("ftrace only works for %s!\n", > #ifdef HAVE_LIBCAP_SUPPORT > - "users with the CAP_PERFMON or CAP_SYS_ADMIN capability" > + "users with the CAP_PERFMON capability" > #else > "root" > #endif > -- > 2.24.1 > -- - Arnaldo