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-rw-r--r--kernel/trace/trace_events_filter.c283
1 files changed, 142 insertions, 141 deletions
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index f04cc3136bd..24aee712745 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -1738,11 +1738,121 @@ static int replace_system_preds(struct event_subsystem *system,
return -ENOMEM;
}
+static int create_filter_start(char *filter_str, bool set_str,
+ struct filter_parse_state **psp,
+ struct event_filter **filterp)
+{
+ struct event_filter *filter;
+ struct filter_parse_state *ps = NULL;
+ int err = 0;
+
+ WARN_ON_ONCE(*psp || *filterp);
+
+ /* allocate everything, and if any fails, free all and fail */
+ filter = __alloc_filter();
+ if (filter && set_str)
+ err = replace_filter_string(filter, filter_str);
+
+ ps = kzalloc(sizeof(*ps), GFP_KERNEL);
+
+ if (!filter || !ps || err) {
+ kfree(ps);
+ __free_filter(filter);
+ return -ENOMEM;
+ }
+
+ /* we're committed to creating a new filter */
+ *filterp = filter;
+ *psp = ps;
+
+ parse_init(ps, filter_ops, filter_str);
+ err = filter_parse(ps);
+ if (err && set_str)
+ append_filter_err(ps, filter);
+ return err;
+}
+
+static void create_filter_finish(struct filter_parse_state *ps)
+{
+ if (ps) {
+ filter_opstack_clear(ps);
+ postfix_clear(ps);
+ kfree(ps);
+ }
+}
+
+/**
+ * create_filter - create a filter for a ftrace_event_call
+ * @call: ftrace_event_call to create a filter for
+ * @filter_str: filter string
+ * @set_str: remember @filter_str and enable detailed error in filter
+ * @filterp: out param for created filter (always updated on return)
+ *
+ * Creates a filter for @call with @filter_str. If @set_str is %true,
+ * @filter_str is copied and recorded in the new filter.
+ *
+ * On success, returns 0 and *@filterp points to the new filter. On
+ * failure, returns -errno and *@filterp may point to %NULL or to a new
+ * filter. In the latter case, the returned filter contains error
+ * information if @set_str is %true and the caller is responsible for
+ * freeing it.
+ */
+static int create_filter(struct ftrace_event_call *call,
+ char *filter_str, bool set_str,
+ struct event_filter **filterp)
+{
+ struct event_filter *filter = NULL;
+ struct filter_parse_state *ps = NULL;
+ int err;
+
+ err = create_filter_start(filter_str, set_str, &ps, &filter);
+ if (!err) {
+ err = replace_preds(call, filter, ps, filter_str, false);
+ if (err && set_str)
+ append_filter_err(ps, filter);
+ }
+ create_filter_finish(ps);
+
+ *filterp = filter;
+ return err;
+}
+
+/**
+ * create_system_filter - create a filter for an event_subsystem
+ * @system: event_subsystem to create a filter for
+ * @filter_str: filter string
+ * @filterp: out param for created filter (always updated on return)
+ *
+ * Identical to create_filter() except that it creates a subsystem filter
+ * and always remembers @filter_str.
+ */
+static int create_system_filter(struct event_subsystem *system,
+ char *filter_str, struct event_filter **filterp)
+{
+ struct event_filter *filter = NULL;
+ struct filter_parse_state *ps = NULL;
+ int err;
+
+ err = create_filter_start(filter_str, true, &ps, &filter);
+ if (!err) {
+ err = replace_system_preds(system, ps, filter_str);
+ if (!err) {
+ /* System filters just show a default message */
+ kfree(filter->filter_string);
+ filter->filter_string = NULL;
+ } else {
+ append_filter_err(ps, filter);
+ }
+ }
+ create_filter_finish(ps);
+
+ *filterp = filter;
+ return err;
+}
+
int apply_event_filter(struct ftrace_event_call *call, char *filter_string)
{
- struct filter_parse_state *ps;
struct event_filter *filter;
- struct event_filter *tmp;
int err = 0;
mutex_lock(&event_mutex);
@@ -1759,49 +1869,30 @@ int apply_event_filter(struct ftrace_event_call *call, char *filter_string)
goto out_unlock;
}
- err = -ENOMEM;
- ps = kzalloc(sizeof(*ps), GFP_KERNEL);
- if (!ps)
- goto out_unlock;
-
- filter = __alloc_filter();
- if (!filter) {
- kfree(ps);
- goto out_unlock;
- }
-
- replace_filter_string(filter, filter_string);
-
- parse_init(ps, filter_ops, filter_string);
- err = filter_parse(ps);
- if (err) {
- append_filter_err(ps, filter);
- goto out;
- }
+ err = create_filter(call, filter_string, true, &filter);
- err = replace_preds(call, filter, ps, filter_string, false);
- if (err) {
- filter_disable(call);
- append_filter_err(ps, filter);
- } else
- call->flags |= TRACE_EVENT_FL_FILTERED;
-out:
/*
* Always swap the call filter with the new filter
* even if there was an error. If there was an error
* in the filter, we disable the filter and show the error
* string
*/
- tmp = call->filter;
- rcu_assign_pointer(call->filter, filter);
- if (tmp) {
- /* Make sure the call is done with the filter */
- synchronize_sched();
- __free_filter(tmp);
+ if (filter) {
+ struct event_filter *tmp = call->filter;
+
+ if (!err)
+ call->flags |= TRACE_EVENT_FL_FILTERED;
+ else
+ filter_disable(call);
+
+ rcu_assign_pointer(call->filter, filter);
+
+ if (tmp) {
+ /* Make sure the call is done with the filter */
+ synchronize_sched();
+ __free_filter(tmp);
+ }
}
- filter_opstack_clear(ps);
- postfix_clear(ps);
- kfree(ps);
out_unlock:
mutex_unlock(&event_mutex);
@@ -1811,7 +1902,6 @@ out_unlock:
int apply_subsystem_event_filter(struct event_subsystem *system,
char *filter_string)
{
- struct filter_parse_state *ps;
struct event_filter *filter;
int err = 0;
@@ -1835,48 +1925,19 @@ int apply_subsystem_event_filter(struct event_subsystem *system,
goto out_unlock;
}
- err = -ENOMEM;
- ps = kzalloc(sizeof(*ps), GFP_KERNEL);
- if (!ps)
- goto out_unlock;
-
- filter = __alloc_filter();
- if (!filter)
- goto out;
-
- /* System filters just show a default message */
- kfree(filter->filter_string);
- filter->filter_string = NULL;
-
- /*
- * No event actually uses the system filter
- * we can free it without synchronize_sched().
- */
- __free_filter(system->filter);
- system->filter = filter;
-
- parse_init(ps, filter_ops, filter_string);
- err = filter_parse(ps);
- if (err)
- goto err_filter;
-
- err = replace_system_preds(system, ps, filter_string);
- if (err)
- goto err_filter;
-
-out:
- filter_opstack_clear(ps);
- postfix_clear(ps);
- kfree(ps);
+ err = create_system_filter(system, filter_string, &filter);
+ if (filter) {
+ /*
+ * No event actually uses the system filter
+ * we can free it without synchronize_sched().
+ */
+ __free_filter(system->filter);
+ system->filter = filter;
+ }
out_unlock:
mutex_unlock(&event_mutex);
return err;
-
-err_filter:
- replace_filter_string(filter, filter_string);
- append_filter_err(ps, system->filter);
- goto out;
}
#ifdef CONFIG_PERF_EVENTS
@@ -1894,7 +1955,6 @@ int ftrace_profile_set_filter(struct perf_event *event, int event_id,
{
int err;
struct event_filter *filter;
- struct filter_parse_state *ps;
struct ftrace_event_call *call;
mutex_lock(&event_mutex);
@@ -1909,33 +1969,10 @@ int ftrace_profile_set_filter(struct perf_event *event, int event_id,
if (event->filter)
goto out_unlock;
- filter = __alloc_filter();
- if (!filter) {
- err = PTR_ERR(filter);
- goto out_unlock;
- }
-
- err = -ENOMEM;
- ps = kzalloc(sizeof(*ps), GFP_KERNEL);
- if (!ps)
- goto free_filter;
-
- parse_init(ps, filter_ops, filter_str);
- err = filter_parse(ps);
- if (err)
- goto free_ps;
-
- err = replace_preds(call, filter, ps, filter_str, false);
+ err = create_filter(call, filter_str, false, &filter);
if (!err)
event->filter = filter;
-
-free_ps:
- filter_opstack_clear(ps);
- postfix_clear(ps);
- kfree(ps);
-
-free_filter:
- if (err)
+ else
__free_filter(filter);
out_unlock:
@@ -1954,43 +1991,6 @@ out_unlock:
#define CREATE_TRACE_POINTS
#include "trace_events_filter_test.h"
-static int test_get_filter(char *filter_str, struct ftrace_event_call *call,
- struct event_filter **pfilter)
-{
- struct event_filter *filter;
- struct filter_parse_state *ps;
- int err = -ENOMEM;
-
- filter = __alloc_filter();
- if (!filter)
- goto out;
-
- ps = kzalloc(sizeof(*ps), GFP_KERNEL);
- if (!ps)
- goto free_filter;
-
- parse_init(ps, filter_ops, filter_str);
- err = filter_parse(ps);
- if (err)
- goto free_ps;
-
- err = replace_preds(call, filter, ps, filter_str, false);
- if (!err)
- *pfilter = filter;
-
- free_ps:
- filter_opstack_clear(ps);
- postfix_clear(ps);
- kfree(ps);
-
- free_filter:
- if (err)
- __free_filter(filter);
-
- out:
- return err;
-}
-
#define DATA_REC(m, va, vb, vc, vd, ve, vf, vg, vh, nvisit) \
{ \
.filter = FILTER, \
@@ -2109,12 +2109,13 @@ static __init int ftrace_test_event_filter(void)
struct test_filter_data_t *d = &test_filter_data[i];
int err;
- err = test_get_filter(d->filter, &event_ftrace_test_filter,
- &filter);
+ err = create_filter(&event_ftrace_test_filter, d->filter,
+ false, &filter);
if (err) {
printk(KERN_INFO
"Failed to get filter for '%s', err %d\n",
d->filter, err);
+ __free_filter(filter);
break;
}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-11 10:06:16 +0000