perf_counter tools: Handle kernels with !CONFIG_PERF_COUNTER

If perf is run on a !CONFIG_PERF_COUNTER kernel right now it
bails out with no messages or with confusing messages.

Standardize this case some more and explain the situation.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

2 files changed, 8 insertions, 7 deletions

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 87866294a0e..deaee42d5eb 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -356,9 +356,6 @@ try_again:
 	if (fd[nr_cpu][counter] < 0) {
 		int err = errno;
 
-		if (verbose)
-			error("sys_perf_counter_open() syscall returned with %d (%s)\n",
-				fd[nr_cpu][counter], strerror(err));
 		if (err == EPERM)
 			die("Permission error - are you root?\n");
 
@@ -376,6 +373,10 @@ try_again:
 			attr->config = PERF_COUNT_CPU_CLOCK;
 			goto try_again;
 		}
+		printf("\n");
+		error("perfcounter syscall returned with %d (%s)\n",
+			fd[nr_cpu][counter], strerror(err));
+		die("No CONFIG_PERF_COUNTERS=y kernel support configured?\n");
 		exit(-1);
 	}
 
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 1f8c97d5c32..be1698f1189 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -551,10 +551,6 @@ try_again:
 	if (fd[i][counter] < 0) {
 		int err = errno;
 
-		if (verbose)
-			error("sys_perf_counter_open() syscall returned with %d (%s)\n",
-				fd[i][counter], strerror(err));
-
 		if (err == EPERM)
 			die("No permission - are you root?\n");
 		/*
@@ -572,6 +568,10 @@ try_again:
 			attr->config = PERF_COUNT_CPU_CLOCK;
 			goto try_again;
 		}
+		printf("\n");
+		error("perfcounter syscall returned with %d (%s)\n",
+			fd[i][counter], strerror(err));
+		die("No CONFIG_PERF_COUNTERS=y kernel support configured?\n");
 		exit(-1);
 	}
 	assert(fd[i][counter] >= 0);