perf target: Introduce perf_target_errno

The perf_target_errno enumerations are used to indicate specific error
cases on perf target operations. It'd help libperf being a more generic
library.

Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Suggested-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Reviewed-by: David Ahern <dsahern@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1336367344-28071-4-git-send-email-namhyung.kim@lge.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

2 files changed, 46 insertions, 12 deletions

diff --git a/tools/perf/util/target.c b/tools/perf/util/target.c
index 3fadf85dd7e3..5c59dcfc8f8d 100644
--- a/tools/perf/util/target.c
+++ b/tools/perf/util/target.c
@@ -10,36 +10,47 @@
 #include "debug.h"
 
 
-void perf_target__validate(struct perf_target *target)
+enum perf_target_errno perf_target__validate(struct perf_target *target)
 {
+        enum perf_target_errno ret = PERF_ERRNO_TARGET__SUCCESS;
+
         if (target->pid)
                 target->tid = target->pid;
 
         /* CPU and PID are mutually exclusive */
         if (target->tid && target->cpu_list) {
-                ui__warning("WARNING: PID switch overriding CPU\n");
-                sleep(1);
                 target->cpu_list = NULL;
+                if (ret == PERF_ERRNO_TARGET__SUCCESS)
+                        ret = PERF_ERRNO_TARGET__PID_OVERRIDE_CPU;
         }
 
         /* UID and PID are mutually exclusive */
         if (target->tid && target->uid_str) {
-                ui__warning("PID/TID switch overriding UID\n");
-                sleep(1);
                 target->uid_str = NULL;
+                if (ret == PERF_ERRNO_TARGET__SUCCESS)
+                        ret = PERF_ERRNO_TARGET__PID_OVERRIDE_UID;
         }
 
         /* UID and CPU are mutually exclusive */
         if (target->uid_str && target->cpu_list) {
-                ui__warning("UID switch overriding CPU\n");
-                sleep(1);
                 target->cpu_list = NULL;
+                if (ret == PERF_ERRNO_TARGET__SUCCESS)
+                        ret = PERF_ERRNO_TARGET__UID_OVERRIDE_CPU;
         }
 
-        /* PID/UID and SYSTEM are mutually exclusive */
-        if ((target->tid || target->uid_str) && target->system_wide) {
-                ui__warning("PID/TID/UID switch overriding CPU\n");
-                sleep(1);
+        /* PID and SYSTEM are mutually exclusive */
+        if (target->tid && target->system_wide) {
                 target->system_wide = false;
+                if (ret == PERF_ERRNO_TARGET__SUCCESS)
+                        ret = PERF_ERRNO_TARGET__PID_OVERRIDE_SYSTEM;
         }
+
+        /* UID and SYSTEM are mutually exclusive */
+        if (target->uid_str && target->system_wide) {
+                target->system_wide = false;
+                if (ret == PERF_ERRNO_TARGET__SUCCESS)
+                        ret = PERF_ERRNO_TARGET__UID_OVERRIDE_SYSTEM;
+        }
+
+        return ret;
 }
diff --git a/tools/perf/util/target.h b/tools/perf/util/target.h
index 218291f921ed..eb0d2101154a 100644
--- a/tools/perf/util/target.h
+++ b/tools/perf/util/target.h
@@ -13,6 +13,29 @@ struct perf_target {
         bool         system_wide;
 };
 
-void perf_target__validate(struct perf_target *target);
+enum perf_target_errno {
+        PERF_ERRNO_TARGET__SUCCESS              = 0,
+
+        /*
+         * Choose an arbitrary negative big number not to clash with standard
+         * errno since SUS requires the errno has distinct positive values.
+         * See 'Issue 6' in the link below.
+         *
+         * http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/errno.h.html
+         */
+        __PERF_ERRNO_TARGET__START              = -10000,
+
+
+        /* for perf_target__validate() */
+        PERF_ERRNO_TARGET__PID_OVERRIDE_CPU     = __PERF_ERRNO_TARGET__START,
+        PERF_ERRNO_TARGET__PID_OVERRIDE_UID,
+        PERF_ERRNO_TARGET__UID_OVERRIDE_CPU,
+        PERF_ERRNO_TARGET__PID_OVERRIDE_SYSTEM,
+        PERF_ERRNO_TARGET__UID_OVERRIDE_SYSTEM,
+
+        __PERF_ERRNO_TARGET__END,
+};
+
+enum perf_target_errno perf_target__validate(struct perf_target *target);
 
 #endif /* _PERF_TARGET_H */