[PATCH 4/5] perf trace: Obtain errno values by using arch_errno_to_name()

[Hendrik Brueckner <brueckner@linux.vnet.ibm.com>]

Replace the errno_to_name() from the audit-libs with the newly
introduced arch_errno_to_name() function.

With this change:

1.  With replacing errno_to_name() from audit-libs, perf trace
    does no longer require audit-lib interfaces.

2. In addition to 1, the audit-libs dependency can be removed
   for architectures that support syscall tables in perf.
   This is achieved in a follow-up commit.

3. With the architecture specific errno number/name mapping,
   perf trace reports can work across architectures.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
---
 tools/perf/builtin-trace.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index 0362974..f7a57b6 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -21,6 +21,7 @@
 #include "builtin.h"
 #include "util/color.h"
 #include "util/debug.h"
+#include "util/env.h"
 #include "util/event.h"
 #include "util/evlist.h"
 #include <subcmd/exec-cmd.h>
@@ -42,17 +43,16 @@
 #include "string2.h"
 #include "syscalltbl.h"
 #include "rb_resort.h"
+#include "util/errno-names.h"
 
 #include <errno.h>
 #include <inttypes.h>
-#include <libaudit.h> /* FIXME: Still needed for audit_errno_to_name */
 #include <poll.h>
 #include <signal.h>
 #include <stdlib.h>
 #include <string.h>
 #include <linux/err.h>
 #include <linux/filter.h>
-#include <linux/audit.h>
 #include <linux/kernel.h>
 #include <linux/random.h>
 #include <linux/stringify.h>
@@ -1660,6 +1660,14 @@ static int trace__fprintf_callchain(struct trace *trace, struct perf_sample *sam
 	return sample__fprintf_callchain(sample, 38, print_opts, &callchain_cursor, trace->output);
 }
 
+static const char *errno_to_name(struct perf_evsel *evsel, int err)
+{
+	struct perf_env *env = perf_evsel__env(evsel);
+	const char *arch_name = perf_env__arch(env);
+
+	return arch_errno_to_name(arch_name, err);
+}
+
 static int trace__sys_exit(struct trace *trace, struct perf_evsel *evsel,
 			   union perf_event *event __maybe_unused,
 			   struct perf_sample *sample)
@@ -1730,7 +1738,7 @@ static int trace__sys_exit(struct trace *trace, struct perf_evsel *evsel,
 errno_print: {
 		char bf[STRERR_BUFSIZE];
 		const char *emsg = str_error_r(-ret, bf, sizeof(bf)),
-			   *e = audit_errno_to_name(-ret);
+			   *e = errno_to_name(evsel, -ret);
 
 		fprintf(trace->output, ") = -1 %s %s", e, emsg);
 	}
-- 
1.8.3.1