[PATCH 1/6] tracing/filters: refactor subsystem filter code

Li Zefan
2009-09-07T08:13:40Z

Change:
for_each_pred
for_each_subsystem
To:
for_each_subsystem
for_each_pred

This change also prepares for the next patch.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
---
kernel/trace/trace.h | 1 -
kernel/trace/trace_events_filter.c | 124 +++++++++++++-----------------------
2 files changed, 45 insertions(+), 80 deletions(-)

diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index ea7e0bc..2b47eba 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -790,7 +790,6 @@ 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 93660fb..f9afbdf 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -458,14 +458,7 @@ 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;

@@ -476,14 +469,6 @@ 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);
}
@@ -657,44 +642,6 @@ 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)
@@ -1048,8 +995,7 @@ 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)
@@ -1096,11 +1042,7 @@ 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;
@@ -1111,6 +1053,44 @@ 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;
@@ -1145,7 +1125,7 @@ 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);

@@ -1173,7 +1153,7 @@ 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;
@@ -1193,23 +1173,9 @@ 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);
--
1.6.3