perf trace: Move syscall table id <-> name routines to separate class

We're using libaudit for doing name to id and id to syscall name
translations, but that makes 'perf trace' to have to wait for newer
libaudit versions supporting recently added syscalls, such as
"userfaultfd" at the time of this changeset.

We have all the information right there, in the kernel sources, so move
this code to a separate place, wrapped behind functions that will
progressively use the kernel source files to extract the syscall table
for use in 'perf trace'.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-i38opd09ow25mmyrvfwnbvkj@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index 8440e2b..11290b5 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -34,8 +34,9 @@
 #include "trace-event.h"
 #include "util/parse-events.h"
 #include "util/bpf-loader.h"
+#include "syscalltbl.h"
 
-#include <libaudit.h>
+#include <libaudit.h> /* FIXME: Still needed for audit_errno_to_name */
 #include <stdlib.h>
 #include <sys/mman.h>
 #include <linux/futex.h>
@@ -114,10 +115,7 @@
 
 struct trace {
 	struct perf_tool	tool;
-	struct {
-		int		machine;
-		int		open_id;
-	}			audit;
+	struct syscalltbl	*sctbl;
 	struct {
 		int		max;
 		struct syscall  *table;
@@ -163,6 +161,7 @@
 	bool			force;
 	bool			vfs_getname;
 	int			trace_pgfaults;
+	int			open_id;
 };
 
 struct tp_field {
@@ -1780,7 +1779,7 @@
 {
 	char tp_name[128];
 	struct syscall *sc;
-	const char *name = audit_syscall_to_name(id, trace->audit.machine);
+	const char *name = syscalltbl__name(trace->sctbl, id);
 
 	if (name == NULL)
 		return -1;
@@ -1855,7 +1854,7 @@
 
 	strlist__for_each(pos, trace->ev_qualifier) {
 		const char *sc = pos->s;
-		int id = audit_name_to_syscall(sc, trace->audit.machine);
+		int id = syscalltbl__id(trace->sctbl, sc);
 
 		if (id < 0) {
 			if (err == 0) {
@@ -2137,7 +2136,7 @@
 
 	ret = perf_evsel__sc_tp_uint(evsel, ret, sample);
 
-	if (id == trace->audit.open_id && ret >= 0 && ttrace->filename.pending_open) {
+	if (id == trace->open_id && ret >= 0 && ttrace->filename.pending_open) {
 		trace__set_fd_pathname(thread, ret, ttrace->filename.name);
 		ttrace->filename.pending_open = false;
 		++trace->stats.vfs_getname;
@@ -3189,10 +3188,6 @@
 		NULL
 	};
 	struct trace trace = {
-		.audit = {
-			.machine = audit_detect_machine(),
-			.open_id = audit_name_to_syscall("open", trace.audit.machine),
-		},
 		.syscalls = {
 			. max = -1,
 		},
@@ -3267,8 +3262,9 @@
 	signal(SIGFPE, sighandler_dump_stack);
 
 	trace.evlist = perf_evlist__new();
+	trace.sctbl = syscalltbl__new();
 
-	if (trace.evlist == NULL) {
+	if (trace.evlist == NULL || trace.sctbl == NULL) {
 		pr_err("Not enough memory to run!\n");
 		err = -ENOMEM;
 		goto out;
@@ -3306,6 +3302,8 @@
 		}
 	}
 
+	trace.open_id = syscalltbl__id(trace.sctbl, "open");
+
 	if (ev_qualifier_str != NULL) {
 		const char *s = ev_qualifier_str;
 		struct strlist_config slist_config = {