tracing/filters: Refactor subsystem filter code

Change:
	for_each_pred
		for_each_subsystem
To:
	for_each_subsystem
		for_each_pred

This change also prepares for later patches.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <4AD69502.8060903@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index acef8b4636f0b605d640567a29096fe6200cec19..628614532d160d0c0e3de07e99ac058433162cca 100644 (file)
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -683,7 +683,6 @@ struct event_filter {
        int                     n_preds;
        struct filter_pred      **preds;
        char                    *filter_string;
-       bool                    no_reset;
 };
 
 struct event_subsystem {

diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 92672016da284ddaa8a004237425d2d393995faf..9c4f9a0dae2b0917b019537520fc9fd056de0095 100644 (file)
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -615,14 +615,7 @@ static int init_subsystem_preds(struct event_subsystem *system)
        return 0;
 }
 
-enum {
-       FILTER_DISABLE_ALL,
-       FILTER_INIT_NO_RESET,
-       FILTER_SKIP_NO_RESET,
-};
-
-static void filter_free_subsystem_preds(struct event_subsystem *system,
-                                       int flag)
+static void filter_free_subsystem_preds(struct event_subsystem *system)
 {
        struct ftrace_event_call *call;
 
@@ -633,14 +626,6 @@ static void filter_free_subsystem_preds(struct event_subsystem *system,
                if (strcmp(call->system, system->name) != 0)
                        continue;
 
-               if (flag == FILTER_INIT_NO_RESET) {
-                       call->filter->no_reset = false;
-                       continue;
-               }
-
-               if (flag == FILTER_SKIP_NO_RESET && call->filter->no_reset)
-                       continue;
-
                filter_disable_preds(call);
                remove_filter_string(call->filter);
        }
@@ -817,44 +802,6 @@ add_pred_fn:
        return 0;
 }
 
-static int filter_add_subsystem_pred(struct filter_parse_state *ps,
-                                    struct event_subsystem *system,
-                                    struct filter_pred *pred,
-                                    char *filter_string,
-                                    bool dry_run)
-{
-       struct ftrace_event_call *call;
-       int err = 0;
-       bool fail = true;
-
-       list_for_each_entry(call, &ftrace_events, list) {
-
-               if (!call->define_fields)
-                       continue;
-
-               if (strcmp(call->system, system->name))
-                       continue;
-
-               if (call->filter->no_reset)
-                       continue;
-
-               err = filter_add_pred(ps, call, pred, dry_run);
-               if (err)
-                       call->filter->no_reset = true;
-               else
-                       fail = false;
-
-               if (!dry_run)
-                       replace_filter_string(call->filter, filter_string);
-       }
-
-       if (fail) {
-               parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0);
-               return err;
-       }
-       return 0;
-}
-
 static void parse_init(struct filter_parse_state *ps,
                       struct filter_op *ops,
                       char *infix_string)
@@ -1209,8 +1156,7 @@ static int check_preds(struct filter_parse_state *ps)
        return 0;
 }
 
-static int replace_preds(struct event_subsystem *system,
-                        struct ftrace_event_call *call,
+static int replace_preds(struct ftrace_event_call *call,
                         struct filter_parse_state *ps,
                         char *filter_string,
                         bool dry_run)
@@ -1257,11 +1203,7 @@ static int replace_preds(struct event_subsystem *system,
 add_pred:
                if (!pred)
                        return -ENOMEM;
-               if (call)
-                       err = filter_add_pred(ps, call, pred, false);
-               else
-                       err = filter_add_subsystem_pred(ps, system, pred,
-                                               filter_string, dry_run);
+               err = filter_add_pred(ps, call, pred, dry_run);
                filter_free_pred(pred);
                if (err)
                        return err;
@@ -1272,6 +1214,44 @@ add_pred:
        return 0;
 }
 
+static int replace_system_preds(struct event_subsystem *system,
+                               struct filter_parse_state *ps,
+                               char *filter_string)
+{
+       struct ftrace_event_call *call;
+       int err;
+       bool fail = true;
+
+       list_for_each_entry(call, &ftrace_events, list) {
+
+               if (!call->define_fields)
+                       continue;
+
+               if (strcmp(call->system, system->name) != 0)
+                       continue;
+
+               /* try to see if the filter can be applied */
+               err = replace_preds(call, ps, filter_string, true);
+               if (err)
+                       continue;
+
+               /* really apply the filter */
+               filter_disable_preds(call);
+               err = replace_preds(call, ps, filter_string, false);
+               if (err)
+                       filter_disable_preds(call);
+               else
+                       replace_filter_string(call->filter, filter_string);
+               fail = false;
+       }
+
+       if (fail) {
+               parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0);
+               return err;
+       }
+       return 0;
+}
+
 int apply_event_filter(struct ftrace_event_call *call, char *filter_string)
 {
        int err;
@@ -1306,7 +1286,7 @@ int apply_event_filter(struct ftrace_event_call *call, char *filter_string)
                goto out;
        }
 
-       err = replace_preds(NULL, call, ps, filter_string, false);
+       err = replace_preds(call, ps, filter_string, false);
        if (err)
                append_filter_err(ps, call->filter);
 
@@ -1334,7 +1314,7 @@ int apply_subsystem_event_filter(struct event_subsystem *system,
                goto out_unlock;
 
        if (!strcmp(strstrip(filter_string), "0")) {
-               filter_free_subsystem_preds(system, FILTER_DISABLE_ALL);
+               filter_free_subsystem_preds(system);
                remove_filter_string(system->filter);
                mutex_unlock(&event_mutex);
                return 0;
@@ -1354,23 +1334,9 @@ int apply_subsystem_event_filter(struct event_subsystem *system,
                goto out;
        }
 
-       filter_free_subsystem_preds(system, FILTER_INIT_NO_RESET);
-
-       /* try to see the filter can be applied to which events */
-       err = replace_preds(system, NULL, ps, filter_string, true);
-       if (err) {
-               append_filter_err(ps, system->filter);
-               goto out;
-       }
-
-       filter_free_subsystem_preds(system, FILTER_SKIP_NO_RESET);
-
-       /* really apply the filter to the events */
-       err = replace_preds(system, NULL, ps, filter_string, false);
-       if (err) {
+       err = replace_system_preds(system, ps, filter_string);
+       if (err)
                append_filter_err(ps, system->filter);
-               filter_free_subsystem_preds(system, 2);
-       }
 
 out:
        filter_opstack_clear(ps);