[PATCH 25/32] tracing: Allow whitespace to surround hist trigger filter

[Tom Zanussi]

The existing code only allows for one space before and after the 'if'
specifying the filter for a hist trigger.  Add code to make that more
permissive as far as whitespace goes.

Signed-off-by: Tom Zanussi <tom.zanu...@linux.intel.com>
---
 kernel/trace/trace_events_hist.c | 19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index d191f1a..53a0634 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -4632,7 +4632,7 @@ static int event_hist_trigger_func(struct event_command 
*cmd_ops,
        struct event_trigger_ops *trigger_ops;
        struct hist_trigger_data *hist_data;
        bool remove = false;
-       char *trigger;
+       char *trigger, *p;
        int ret = 0;
 
        if (!param)
@@ -4642,9 +4642,19 @@ static int event_hist_trigger_func(struct event_command 
*cmd_ops,
                remove = true;
 
        /* separate the trigger from the filter (k:v [if filter]) */
-       trigger = strsep(&param, " \t");
-       if (!trigger)
-               return -EINVAL;
+       trigger = param;
+       p = strstr(param, " if");
+       if (!p)
+               p = strstr(param, "\tif");
+       if (p) {
+               if (p == trigger)
+                       return -EINVAL;
+               param = p + 1;
+               param = strstrip(param);
+               *p = '\0';
+               trigger = strstrip(trigger);
+       } else
+               param = NULL;
 
        attrs = parse_hist_trigger_attrs(trigger);
        if (IS_ERR(attrs))
@@ -4694,6 +4704,7 @@ static int event_hist_trigger_func(struct event_command 
*cmd_ops,
        }
 
        ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file);
+
        /*
         * The above returns on success the # of triggers registered,
         * but if it didn't register any it returns zero.  Consider no
-- 
1.9.3