[tip:perf/urgent] perf syscalltbl: Support glob matching on syscall names

[tip-bot for Arnaldo Carvalho de Melo]

Commit-ID:  89be3f8ab701180fc0329eff1b076528d64ac56b
Gitweb:     http://git.kernel.org/tip/89be3f8ab701180fc0329eff1b076528d64ac56b
Author:     Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
AuthorDate: Thu, 31 Aug 2017 11:46:49 -0300
Committer:  Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Fri, 1 Sep 2017 14:45:48 -0300

perf syscalltbl: Support glob matching on syscall names

With two new methods, one to find the first match, returning its syscall
id and its index in whatever internal database it keeps the syscall
into, then one to find the next match, if any.

Implemented only on arches where we actually read the syscall table from
the kernel sources, i.e. x86-64 for now, all the others use the libaudit
method for which this returns -1, i.e. just stubs were added, with the
actual implementation using whatever libaudit functions for matching
that may be available.

Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Wang Nan <wangnan0@xxxxxxxxxx>
Link: http://lkml.kernel.org/n/tip-i0sj4rxk1a63pfe9gl8z8irs@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 tools/perf/util/syscalltbl.c | 33 +++++++++++++++++++++++++++++++++
 tools/perf/util/syscalltbl.h |  3 +++
 2 files changed, 36 insertions(+)

diff --git a/tools/perf/util/syscalltbl.c b/tools/perf/util/syscalltbl.c
index bbb4c19..19e5db9 100644
--- a/tools/perf/util/syscalltbl.c
+++ b/tools/perf/util/syscalltbl.c
@@ -19,6 +19,7 @@
 #ifdef HAVE_SYSCALL_TABLE
 #include <linux/compiler.h>
 #include <string.h>
+#include "string2.h"
 #include "util.h"
 
 #if defined(__x86_64__)
@@ -105,6 +106,27 @@ int syscalltbl__id(struct syscalltbl *tbl, const char *name)
 	return sc ? sc->id : -1;
 }
 
+int syscalltbl__strglobmatch_next(struct syscalltbl *tbl, const char *syscall_glob, int *idx)
+{
+	int i;
+	struct syscall *syscalls = tbl->syscalls.entries;
+
+	for (i = *idx + 1; i < tbl->syscalls.nr_entries; ++i) {
+		if (strglobmatch(syscalls[i].name, syscall_glob)) {
+			*idx = i;
+			return syscalls[i].id;
+		}
+	}
+
+	return -1;
+}
+
+int syscalltbl__strglobmatch_first(struct syscalltbl *tbl, const char *syscall_glob, int *idx)
+{
+	*idx = -1;
+	return syscalltbl__strglobmatch_next(tbl, syscall_glob, idx);
+}
+
 #else /* HAVE_SYSCALL_TABLE */
 
 #include <libaudit.h>
@@ -131,4 +153,15 @@ int syscalltbl__id(struct syscalltbl *tbl, const char *name)
 {
 	return audit_name_to_syscall(name, tbl->audit_machine);
 }
+
+int syscalltbl__strglobmatch_next(struct syscalltbl *tbl __maybe_unused,
+				  const char *syscall_glob __maybe_unused, int *idx __maybe_unused)
+{
+	return -1;
+}
+
+int syscalltbl__strglobmatch_first(struct syscalltbl *tbl, const char *syscall_glob, int *idx)
+{
+	return syscalltbl__strglobmatch_next(tbl, syscall_glob, idx);
+}
 #endif /* HAVE_SYSCALL_TABLE */
diff --git a/tools/perf/util/syscalltbl.h b/tools/perf/util/syscalltbl.h
index e295151..e9fb878 100644
--- a/tools/perf/util/syscalltbl.h
+++ b/tools/perf/util/syscalltbl.h
@@ -17,4 +17,7 @@ void syscalltbl__delete(struct syscalltbl *tbl);
 const char *syscalltbl__name(const struct syscalltbl *tbl, int id);
 int syscalltbl__id(struct syscalltbl *tbl, const char *name);
 
+int syscalltbl__strglobmatch_first(struct syscalltbl *tbl, const char *syscall_glob, int *idx);
+int syscalltbl__strglobmatch_next(struct syscalltbl *tbl, const char *syscall_glob, int *idx);
+
 #endif /* __PERF_SYSCALLTBL_H */