Now that we have two mountpoints, one for debugfs and another, for
tracefs, we end up needing to check permissions for both, so, on
a system with default config we were always asking the user to
check the permission of the debugfs mountpoint, even when it was
already sufficient. Fix it.
E.g.:
$ trace -e nanosleep usleep 1
Error: No permissions to read /sys/kernel/debug/tracing/events/raw_syscalls/sys_(enter|exit)
Hint: Try 'sudo mount -o remount,mode=755 /sys/kernel/debug'
$ sudo mount -o remount,mode=755 /sys/kernel/debug
$ trace -e nanosleep usleep 1
Error: No permissions to read /sys/kernel/debug/tracing/events/raw_syscalls/sys_(enter|exit)
Hint: Try 'sudo mount -o remount,mode=755 /sys/kernel/debug/tracing'
$ sudo mount -o remount,mode=755 /sys/kernel/debug/tracing
$ trace -e nanosleep usleep 1
0.326 ( 0.061 ms): usleep/11961 nanosleep(rqtp: 0x7ffef1081c50) = 0
$
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/n/tip-0viljeuhc7q84ic8kobsna43@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
ab85785aa1