[RFC PATCH 7/9] perf: Support for error passed over pointers

[Frederic Weisbecker <fweisbec@gmail.com>]

Export the linux/err.h that carries the ERR_PTR/PTR_ERR/IS_ERR
macros so that they also become usable by perf.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Robert Richter <robert.richter@amd.com>
---
 tools/perf/Makefile                 |    1 +
 tools/perf/util/include/linux/err.h |   24 ++++++++++++++++++++++++
 2 files changed, 25 insertions(+), 0 deletions(-)
 create mode 100644 tools/perf/util/include/linux/err.h

diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index 28de60b..1146195 100644
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -375,6 +375,7 @@ LIB_H += util/include/linux/prefetch.h
 LIB_H += util/include/linux/rbtree.h
 LIB_H += util/include/linux/string.h
 LIB_H += util/include/linux/types.h
+LIB_H += util/include/linux/err.h
 LIB_H += util/include/asm/asm-offsets.h
 LIB_H += util/include/asm/bug.h
 LIB_H += util/include/asm/byteorder.h
diff --git a/tools/perf/util/include/linux/err.h b/tools/perf/util/include/linux/err.h
new file mode 100644
index 0000000..4e6dc36
--- /dev/null
+++ b/tools/perf/util/include/linux/err.h
@@ -0,0 +1,24 @@
+#ifndef PERF_ERR_H
+#define PERF_ERR_H
+
+
+#define MAX_ERRNO	4095
+
+#define IS_ERR_VALUE(x) ((x) >= (unsigned long)-MAX_ERRNO)
+
+static inline void *ERR_PTR(long err)
+{
+	return (void *) err;
+}
+
+static inline long PTR_ERR(const void *ptr)
+{
+	return (long) ptr;
+}
+
+static inline long IS_ERR(const void *ptr)
+{
+	return IS_ERR_VALUE((unsigned long)ptr);
+}
+
+#endif /* PERF_ERR_H */
-- 
1.6.2.3