2 * trace_events_filter - generic event filtering
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
18 * Copyright (C) 2009 Tom Zanussi <tzanussi@gmail.com>
21 #include <linux/debugfs.h>
22 #include <linux/uaccess.h>
23 #include <linux/module.h>
24 #include <linux/ctype.h>
25 #include <linux/mutex.h>
28 #include "trace_output.h"
50 static struct filter_op filter_ops[] = {
59 { OP_NONE, "OP_NONE", 0 },
60 { OP_OPEN_PAREN, "(", 0 },
66 FILT_ERR_UNBALANCED_PAREN,
67 FILT_ERR_TOO_MANY_OPERANDS,
68 FILT_ERR_OPERAND_TOO_LONG,
69 FILT_ERR_FIELD_NOT_FOUND,
70 FILT_ERR_ILLEGAL_FIELD_OP,
71 FILT_ERR_ILLEGAL_INTVAL,
72 FILT_ERR_BAD_SUBSYS_FILTER,
73 FILT_ERR_TOO_MANY_PREDS,
74 FILT_ERR_MISSING_FIELD,
75 FILT_ERR_INVALID_FILTER,
78 static char *err_text[] = {
85 "Illegal operation for field type",
86 "Illegal integer value",
87 "Couldn't find or set field in one of a subsystem's events",
88 "Too many terms in predicate expression",
89 "Missing field name and/or value",
90 "Meaningless filter expression",
95 struct list_head list;
101 struct list_head list;
104 struct filter_parse_state {
105 struct filter_op *ops;
106 struct list_head opstack;
107 struct list_head postfix;
118 char string[MAX_FILTER_STR_VAL];
124 #define DEFINE_COMPARISON_PRED(type) \
125 static int filter_pred_##type(struct filter_pred *pred, void *event, \
126 int val1, int val2) \
128 type *addr = (type *)(event + pred->offset); \
129 type val = (type)pred->val; \
132 switch (pred->op) { \
134 match = (*addr < val); \
137 match = (*addr <= val); \
140 match = (*addr > val); \
143 match = (*addr >= val); \
152 #define DEFINE_EQUALITY_PRED(size) \
153 static int filter_pred_##size(struct filter_pred *pred, void *event, \
154 int val1, int val2) \
156 u##size *addr = (u##size *)(event + pred->offset); \
157 u##size val = (u##size)pred->val; \
160 match = (val == *addr) ^ pred->not; \
165 DEFINE_COMPARISON_PRED(s64);
166 DEFINE_COMPARISON_PRED(u64);
167 DEFINE_COMPARISON_PRED(s32);
168 DEFINE_COMPARISON_PRED(u32);
169 DEFINE_COMPARISON_PRED(s16);
170 DEFINE_COMPARISON_PRED(u16);
171 DEFINE_COMPARISON_PRED(s8);
172 DEFINE_COMPARISON_PRED(u8);
174 DEFINE_EQUALITY_PRED(64);
175 DEFINE_EQUALITY_PRED(32);
176 DEFINE_EQUALITY_PRED(16);
177 DEFINE_EQUALITY_PRED(8);
179 static int filter_pred_and(struct filter_pred *pred __attribute((unused)),
180 void *event __attribute((unused)),
186 static int filter_pred_or(struct filter_pred *pred __attribute((unused)),
187 void *event __attribute((unused)),
193 /* Filter predicate for fixed sized arrays of characters */
194 static int filter_pred_string(struct filter_pred *pred, void *event,
197 char *addr = (char *)(event + pred->offset);
200 cmp = strncmp(addr, pred->str_val, pred->str_len);
202 match = (!cmp) ^ pred->not;
207 /* Filter predicate for char * pointers */
208 static int filter_pred_pchar(struct filter_pred *pred, void *event,
211 char **addr = (char **)(event + pred->offset);
214 cmp = strncmp(*addr, pred->str_val, pred->str_len);
216 match = (!cmp) ^ pred->not;
222 * Filter predicate for dynamic sized arrays of characters.
223 * These are implemented through a list of strings at the end
225 * Also each of these strings have a field in the entry which
226 * contains its offset from the beginning of the entry.
227 * We have then first to get this field, dereference it
228 * and add it to the address of the entry, and at last we have
229 * the address of the string.
231 static int filter_pred_strloc(struct filter_pred *pred, void *event,
234 u32 str_item = *(u32 *)(event + pred->offset);
235 int str_loc = str_item & 0xffff;
236 int str_len = str_item >> 16;
237 char *addr = (char *)(event + str_loc);
240 cmp = strncmp(addr, pred->str_val, str_len);
242 match = (!cmp) ^ pred->not;
247 static int filter_pred_none(struct filter_pred *pred, void *event,
253 /* return 1 if event matches, 0 otherwise (discard) */
254 int filter_match_preds(struct ftrace_event_call *call, void *rec)
256 struct event_filter *filter = call->filter;
257 int match, top = 0, val1 = 0, val2 = 0;
258 int stack[MAX_FILTER_PRED];
259 struct filter_pred *pred;
262 for (i = 0; i < filter->n_preds; i++) {
263 pred = filter->preds[i];
265 match = pred->fn(pred, rec, val1, val2);
266 stack[top++] = match;
269 if (pred->pop_n > top) {
275 match = pred->fn(pred, rec, val1, val2);
276 stack[top++] = match;
281 EXPORT_SYMBOL_GPL(filter_match_preds);
283 static void parse_error(struct filter_parse_state *ps, int err, int pos)
286 ps->lasterr_pos = pos;
289 static void remove_filter_string(struct event_filter *filter)
291 kfree(filter->filter_string);
292 filter->filter_string = NULL;
295 static int replace_filter_string(struct event_filter *filter,
298 kfree(filter->filter_string);
299 filter->filter_string = kstrdup(filter_string, GFP_KERNEL);
300 if (!filter->filter_string)
306 static int append_filter_string(struct event_filter *filter,
310 char *new_filter_string;
312 BUG_ON(!filter->filter_string);
313 newlen = strlen(filter->filter_string) + strlen(string) + 1;
314 new_filter_string = kmalloc(newlen, GFP_KERNEL);
315 if (!new_filter_string)
318 strcpy(new_filter_string, filter->filter_string);
319 strcat(new_filter_string, string);
320 kfree(filter->filter_string);
321 filter->filter_string = new_filter_string;
326 static void append_filter_err(struct filter_parse_state *ps,
327 struct event_filter *filter)
329 int pos = ps->lasterr_pos;
332 buf = (char *)__get_free_page(GFP_TEMPORARY);
336 append_filter_string(filter, "\n");
337 memset(buf, ' ', PAGE_SIZE);
338 if (pos > PAGE_SIZE - 128)
341 pbuf = &buf[pos] + 1;
343 sprintf(pbuf, "\nparse_error: %s\n", err_text[ps->lasterr]);
344 append_filter_string(filter, buf);
345 free_page((unsigned long) buf);
348 void print_event_filter(struct ftrace_event_call *call, struct trace_seq *s)
350 struct event_filter *filter = call->filter;
352 mutex_lock(&event_mutex);
353 if (filter && filter->filter_string)
354 trace_seq_printf(s, "%s\n", filter->filter_string);
356 trace_seq_printf(s, "none\n");
357 mutex_unlock(&event_mutex);
360 void print_subsystem_event_filter(struct event_subsystem *system,
363 struct event_filter *filter = system->filter;
365 mutex_lock(&event_mutex);
366 if (filter && filter->filter_string)
367 trace_seq_printf(s, "%s\n", filter->filter_string);
369 trace_seq_printf(s, "none\n");
370 mutex_unlock(&event_mutex);
373 static struct ftrace_event_field *
374 find_event_field(struct ftrace_event_call *call, char *name)
376 struct ftrace_event_field *field;
378 list_for_each_entry(field, &call->fields, link) {
379 if (!strcmp(field->name, name))
386 static void filter_free_pred(struct filter_pred *pred)
391 kfree(pred->field_name);
395 static void filter_clear_pred(struct filter_pred *pred)
397 kfree(pred->field_name);
398 pred->field_name = NULL;
402 static int filter_set_pred(struct filter_pred *dest,
403 struct filter_pred *src,
407 if (src->field_name) {
408 dest->field_name = kstrdup(src->field_name, GFP_KERNEL);
409 if (!dest->field_name)
417 static void filter_disable_preds(struct ftrace_event_call *call)
419 struct event_filter *filter = call->filter;
422 call->filter_active = 0;
425 for (i = 0; i < MAX_FILTER_PRED; i++)
426 filter->preds[i]->fn = filter_pred_none;
429 void destroy_preds(struct ftrace_event_call *call)
431 struct event_filter *filter = call->filter;
437 for (i = 0; i < MAX_FILTER_PRED; i++) {
438 if (filter->preds[i])
439 filter_free_pred(filter->preds[i]);
441 kfree(filter->preds);
442 kfree(filter->filter_string);
447 static int init_preds(struct ftrace_event_call *call)
449 struct event_filter *filter;
450 struct filter_pred *pred;
456 filter = call->filter = kzalloc(sizeof(*filter), GFP_KERNEL);
462 filter->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred), GFP_KERNEL);
466 for (i = 0; i < MAX_FILTER_PRED; i++) {
467 pred = kzalloc(sizeof(*pred), GFP_KERNEL);
470 pred->fn = filter_pred_none;
471 filter->preds[i] = pred;
482 static int init_subsystem_preds(struct event_subsystem *system)
484 struct ftrace_event_call *call;
487 list_for_each_entry(call, &ftrace_events, list) {
488 if (!call->define_fields)
491 if (strcmp(call->system, system->name) != 0)
494 err = init_preds(call);
504 FILTER_INIT_NO_RESET,
505 FILTER_SKIP_NO_RESET,
508 static void filter_free_subsystem_preds(struct event_subsystem *system,
511 struct ftrace_event_call *call;
513 list_for_each_entry(call, &ftrace_events, list) {
514 if (!call->define_fields)
517 if (strcmp(call->system, system->name) != 0)
520 if (flag == FILTER_INIT_NO_RESET) {
521 call->filter->no_reset = false;
525 if (flag == FILTER_SKIP_NO_RESET && call->filter->no_reset)
528 filter_disable_preds(call);
529 remove_filter_string(call->filter);
533 static int filter_add_pred_fn(struct filter_parse_state *ps,
534 struct ftrace_event_call *call,
535 struct filter_pred *pred,
538 struct event_filter *filter = call->filter;
541 if (filter->n_preds == MAX_FILTER_PRED) {
542 parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0);
546 idx = filter->n_preds;
547 filter_clear_pred(filter->preds[idx]);
548 err = filter_set_pred(filter->preds[idx], pred, fn);
553 call->filter_active = 1;
558 int filter_assign_type(const char *type)
560 if (strstr(type, "__data_loc") && strstr(type, "char"))
561 return FILTER_DYN_STRING;
563 if (strchr(type, '[') && strstr(type, "char"))
564 return FILTER_STATIC_STRING;
569 static bool is_string_field(struct ftrace_event_field *field)
571 return field->filter_type == FILTER_DYN_STRING ||
572 field->filter_type == FILTER_STATIC_STRING ||
573 field->filter_type == FILTER_PTR_STRING;
576 static int is_legal_op(struct ftrace_event_field *field, int op)
578 if (is_string_field(field) && (op != OP_EQ && op != OP_NE))
584 static filter_pred_fn_t select_comparison_fn(int op, int field_size,
587 filter_pred_fn_t fn = NULL;
589 switch (field_size) {
591 if (op == OP_EQ || op == OP_NE)
593 else if (field_is_signed)
594 fn = filter_pred_s64;
596 fn = filter_pred_u64;
599 if (op == OP_EQ || op == OP_NE)
601 else if (field_is_signed)
602 fn = filter_pred_s32;
604 fn = filter_pred_u32;
607 if (op == OP_EQ || op == OP_NE)
609 else if (field_is_signed)
610 fn = filter_pred_s16;
612 fn = filter_pred_u16;
615 if (op == OP_EQ || op == OP_NE)
617 else if (field_is_signed)
627 static int filter_add_pred(struct filter_parse_state *ps,
628 struct ftrace_event_call *call,
629 struct filter_pred *pred,
632 struct ftrace_event_field *field;
634 unsigned long long val;
637 pred->fn = filter_pred_none;
639 if (pred->op == OP_AND) {
641 fn = filter_pred_and;
643 } else if (pred->op == OP_OR) {
649 field = find_event_field(call, pred->field_name);
651 parse_error(ps, FILT_ERR_FIELD_NOT_FOUND, 0);
655 pred->offset = field->offset;
657 if (!is_legal_op(field, pred->op)) {
658 parse_error(ps, FILT_ERR_ILLEGAL_FIELD_OP, 0);
662 if (is_string_field(field)) {
663 pred->str_len = field->size;
665 if (field->filter_type == FILTER_STATIC_STRING)
666 fn = filter_pred_string;
667 else if (field->filter_type == FILTER_DYN_STRING)
668 fn = filter_pred_strloc;
670 fn = filter_pred_pchar;
671 pred->str_len = strlen(pred->str_val);
674 if (field->is_signed)
675 ret = strict_strtoll(pred->str_val, 0, &val);
677 ret = strict_strtoull(pred->str_val, 0, &val);
679 parse_error(ps, FILT_ERR_ILLEGAL_INTVAL, 0);
684 fn = select_comparison_fn(pred->op, field->size,
687 parse_error(ps, FILT_ERR_INVALID_OP, 0);
692 if (pred->op == OP_NE)
697 return filter_add_pred_fn(ps, call, pred, fn);
701 static int filter_add_subsystem_pred(struct filter_parse_state *ps,
702 struct event_subsystem *system,
703 struct filter_pred *pred,
707 struct ftrace_event_call *call;
711 list_for_each_entry(call, &ftrace_events, list) {
713 if (!call->define_fields)
716 if (strcmp(call->system, system->name))
719 if (call->filter->no_reset)
722 err = filter_add_pred(ps, call, pred, dry_run);
724 call->filter->no_reset = true;
729 replace_filter_string(call->filter, filter_string);
733 parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0);
739 static void parse_init(struct filter_parse_state *ps,
740 struct filter_op *ops,
743 memset(ps, '\0', sizeof(*ps));
745 ps->infix.string = infix_string;
746 ps->infix.cnt = strlen(infix_string);
749 INIT_LIST_HEAD(&ps->opstack);
750 INIT_LIST_HEAD(&ps->postfix);
753 static char infix_next(struct filter_parse_state *ps)
757 return ps->infix.string[ps->infix.tail++];
760 static char infix_peek(struct filter_parse_state *ps)
762 if (ps->infix.tail == strlen(ps->infix.string))
765 return ps->infix.string[ps->infix.tail];
768 static void infix_advance(struct filter_parse_state *ps)
774 static inline int is_precedence_lower(struct filter_parse_state *ps,
777 return ps->ops[a].precedence < ps->ops[b].precedence;
780 static inline int is_op_char(struct filter_parse_state *ps, char c)
784 for (i = 0; strcmp(ps->ops[i].string, "OP_NONE"); i++) {
785 if (ps->ops[i].string[0] == c)
792 static int infix_get_op(struct filter_parse_state *ps, char firstc)
794 char nextc = infix_peek(ps);
802 for (i = 0; strcmp(ps->ops[i].string, "OP_NONE"); i++) {
803 if (!strcmp(opstr, ps->ops[i].string)) {
805 return ps->ops[i].id;
811 for (i = 0; strcmp(ps->ops[i].string, "OP_NONE"); i++) {
812 if (!strcmp(opstr, ps->ops[i].string))
813 return ps->ops[i].id;
819 static inline void clear_operand_string(struct filter_parse_state *ps)
821 memset(ps->operand.string, '\0', MAX_FILTER_STR_VAL);
822 ps->operand.tail = 0;
825 static inline int append_operand_char(struct filter_parse_state *ps, char c)
827 if (ps->operand.tail == MAX_FILTER_STR_VAL - 1)
830 ps->operand.string[ps->operand.tail++] = c;
835 static int filter_opstack_push(struct filter_parse_state *ps, int op)
837 struct opstack_op *opstack_op;
839 opstack_op = kmalloc(sizeof(*opstack_op), GFP_KERNEL);
844 list_add(&opstack_op->list, &ps->opstack);
849 static int filter_opstack_empty(struct filter_parse_state *ps)
851 return list_empty(&ps->opstack);
854 static int filter_opstack_top(struct filter_parse_state *ps)
856 struct opstack_op *opstack_op;
858 if (filter_opstack_empty(ps))
861 opstack_op = list_first_entry(&ps->opstack, struct opstack_op, list);
863 return opstack_op->op;
866 static int filter_opstack_pop(struct filter_parse_state *ps)
868 struct opstack_op *opstack_op;
871 if (filter_opstack_empty(ps))
874 opstack_op = list_first_entry(&ps->opstack, struct opstack_op, list);
876 list_del(&opstack_op->list);
883 static void filter_opstack_clear(struct filter_parse_state *ps)
885 while (!filter_opstack_empty(ps))
886 filter_opstack_pop(ps);
889 static char *curr_operand(struct filter_parse_state *ps)
891 return ps->operand.string;
894 static int postfix_append_operand(struct filter_parse_state *ps, char *operand)
896 struct postfix_elt *elt;
898 elt = kmalloc(sizeof(*elt), GFP_KERNEL);
903 elt->operand = kstrdup(operand, GFP_KERNEL);
909 list_add_tail(&elt->list, &ps->postfix);
914 static int postfix_append_op(struct filter_parse_state *ps, int op)
916 struct postfix_elt *elt;
918 elt = kmalloc(sizeof(*elt), GFP_KERNEL);
925 list_add_tail(&elt->list, &ps->postfix);
930 static void postfix_clear(struct filter_parse_state *ps)
932 struct postfix_elt *elt;
934 while (!list_empty(&ps->postfix)) {
935 elt = list_first_entry(&ps->postfix, struct postfix_elt, list);
936 list_del(&elt->list);
942 static int filter_parse(struct filter_parse_state *ps)
948 while ((ch = infix_next(ps))) {
960 if (is_op_char(ps, ch)) {
961 op = infix_get_op(ps, ch);
963 parse_error(ps, FILT_ERR_INVALID_OP, 0);
967 if (strlen(curr_operand(ps))) {
968 postfix_append_operand(ps, curr_operand(ps));
969 clear_operand_string(ps);
972 while (!filter_opstack_empty(ps)) {
973 top_op = filter_opstack_top(ps);
974 if (!is_precedence_lower(ps, top_op, op)) {
975 top_op = filter_opstack_pop(ps);
976 postfix_append_op(ps, top_op);
982 filter_opstack_push(ps, op);
987 filter_opstack_push(ps, OP_OPEN_PAREN);
992 if (strlen(curr_operand(ps))) {
993 postfix_append_operand(ps, curr_operand(ps));
994 clear_operand_string(ps);
997 top_op = filter_opstack_pop(ps);
998 while (top_op != OP_NONE) {
999 if (top_op == OP_OPEN_PAREN)
1001 postfix_append_op(ps, top_op);
1002 top_op = filter_opstack_pop(ps);
1004 if (top_op == OP_NONE) {
1005 parse_error(ps, FILT_ERR_UNBALANCED_PAREN, 0);
1011 if (append_operand_char(ps, ch)) {
1012 parse_error(ps, FILT_ERR_OPERAND_TOO_LONG, 0);
1017 if (strlen(curr_operand(ps)))
1018 postfix_append_operand(ps, curr_operand(ps));
1020 while (!filter_opstack_empty(ps)) {
1021 top_op = filter_opstack_pop(ps);
1022 if (top_op == OP_NONE)
1024 if (top_op == OP_OPEN_PAREN) {
1025 parse_error(ps, FILT_ERR_UNBALANCED_PAREN, 0);
1028 postfix_append_op(ps, top_op);
1034 static struct filter_pred *create_pred(int op, char *operand1, char *operand2)
1036 struct filter_pred *pred;
1038 pred = kzalloc(sizeof(*pred), GFP_KERNEL);
1042 pred->field_name = kstrdup(operand1, GFP_KERNEL);
1043 if (!pred->field_name) {
1048 strcpy(pred->str_val, operand2);
1049 pred->str_len = strlen(operand2);
1056 static struct filter_pred *create_logical_pred(int op)
1058 struct filter_pred *pred;
1060 pred = kzalloc(sizeof(*pred), GFP_KERNEL);
1069 static int check_preds(struct filter_parse_state *ps)
1071 int n_normal_preds = 0, n_logical_preds = 0;
1072 struct postfix_elt *elt;
1074 list_for_each_entry(elt, &ps->postfix, list) {
1075 if (elt->op == OP_NONE)
1078 if (elt->op == OP_AND || elt->op == OP_OR) {
1085 if (!n_normal_preds || n_logical_preds >= n_normal_preds) {
1086 parse_error(ps, FILT_ERR_INVALID_FILTER, 0);
1093 static int replace_preds(struct event_subsystem *system,
1094 struct ftrace_event_call *call,
1095 struct filter_parse_state *ps,
1096 char *filter_string,
1099 char *operand1 = NULL, *operand2 = NULL;
1100 struct filter_pred *pred;
1101 struct postfix_elt *elt;
1105 err = check_preds(ps);
1109 list_for_each_entry(elt, &ps->postfix, list) {
1110 if (elt->op == OP_NONE) {
1112 operand1 = elt->operand;
1114 operand2 = elt->operand;
1116 parse_error(ps, FILT_ERR_TOO_MANY_OPERANDS, 0);
1122 if (n_preds++ == MAX_FILTER_PRED) {
1123 parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0);
1127 if (elt->op == OP_AND || elt->op == OP_OR) {
1128 pred = create_logical_pred(elt->op);
1132 if (!operand1 || !operand2) {
1133 parse_error(ps, FILT_ERR_MISSING_FIELD, 0);
1137 pred = create_pred(elt->op, operand1, operand2);
1142 err = filter_add_pred(ps, call, pred, false);
1144 err = filter_add_subsystem_pred(ps, system, pred,
1145 filter_string, dry_run);
1146 filter_free_pred(pred);
1150 operand1 = operand2 = NULL;
1156 int apply_event_filter(struct ftrace_event_call *call, char *filter_string)
1160 struct filter_parse_state *ps;
1162 mutex_lock(&event_mutex);
1164 err = init_preds(call);
1168 if (!strcmp(strstrip(filter_string), "0")) {
1169 filter_disable_preds(call);
1170 remove_filter_string(call->filter);
1171 mutex_unlock(&event_mutex);
1176 ps = kzalloc(sizeof(*ps), GFP_KERNEL);
1180 filter_disable_preds(call);
1181 replace_filter_string(call->filter, filter_string);
1183 parse_init(ps, filter_ops, filter_string);
1184 err = filter_parse(ps);
1186 append_filter_err(ps, call->filter);
1190 err = replace_preds(NULL, call, ps, filter_string, false);
1192 append_filter_err(ps, call->filter);
1195 filter_opstack_clear(ps);
1199 mutex_unlock(&event_mutex);
1204 int apply_subsystem_event_filter(struct event_subsystem *system,
1205 char *filter_string)
1209 struct filter_parse_state *ps;
1211 mutex_lock(&event_mutex);
1213 err = init_subsystem_preds(system);
1217 if (!strcmp(strstrip(filter_string), "0")) {
1218 filter_free_subsystem_preds(system, FILTER_DISABLE_ALL);
1219 remove_filter_string(system->filter);
1220 mutex_unlock(&event_mutex);
1225 ps = kzalloc(sizeof(*ps), GFP_KERNEL);
1229 replace_filter_string(system->filter, filter_string);
1231 parse_init(ps, filter_ops, filter_string);
1232 err = filter_parse(ps);
1234 append_filter_err(ps, system->filter);
1238 filter_free_subsystem_preds(system, FILTER_INIT_NO_RESET);
1240 /* try to see the filter can be applied to which events */
1241 err = replace_preds(system, NULL, ps, filter_string, true);
1243 append_filter_err(ps, system->filter);
1247 filter_free_subsystem_preds(system, FILTER_SKIP_NO_RESET);
1249 /* really apply the filter to the events */
1250 err = replace_preds(system, NULL, ps, filter_string, false);
1252 append_filter_err(ps, system->filter);
1253 filter_free_subsystem_preds(system, 2);
1257 filter_opstack_clear(ps);
1261 mutex_unlock(&event_mutex);