--- /dev/null
+/*
+ * trace_events_filter - generic event filtering
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright (C) 2009 Tom Zanussi <tzanussi@gmail.com>
+ */
+
+#include <linux/debugfs.h>
+#include <linux/uaccess.h>
+#include <linux/module.h>
+#include <linux/ctype.h>
+
+#include "trace.h"
+#include "trace_output.h"
+
+static int filter_pred_64(struct filter_pred *pred, void *event)
+{
+ u64 *addr = (u64 *)(event + pred->offset);
+ u64 val = (u64)pred->val;
+ int match;
+
+ match = (val == *addr) ^ pred->not;
+
+ return match;
+}
+
+static int filter_pred_32(struct filter_pred *pred, void *event)
+{
+ u32 *addr = (u32 *)(event + pred->offset);
+ u32 val = (u32)pred->val;
+ int match;
+
+ match = (val == *addr) ^ pred->not;
+
+ return match;
+}
+
+static int filter_pred_16(struct filter_pred *pred, void *event)
+{
+ u16 *addr = (u16 *)(event + pred->offset);
+ u16 val = (u16)pred->val;
+ int match;
+
+ match = (val == *addr) ^ pred->not;
+
+ return match;
+}
+
+static int filter_pred_8(struct filter_pred *pred, void *event)
+{
+ u8 *addr = (u8 *)(event + pred->offset);
+ u8 val = (u8)pred->val;
+ int match;
+
+ match = (val == *addr) ^ pred->not;
+
+ return match;
+}
+
+static int filter_pred_string(struct filter_pred *pred, void *event)
+{
+ char *addr = (char *)(event + pred->offset);
+ int cmp, match;
+
+ cmp = strncmp(addr, pred->str_val, pred->str_len);
+
+ match = (!cmp) ^ pred->not;
+
+ return match;
+}
+
+/* return 1 if event matches, 0 otherwise (discard) */
+int filter_match_preds(struct ftrace_event_call *call, void *rec)
+{
+ int i, matched, and_failed = 0;
+ struct filter_pred *pred;
+
+ for (i = 0; i < MAX_FILTER_PRED; i++) {
+ if (call->preds[i]) {
+ pred = call->preds[i];
+ if (and_failed && !pred->or)
+ continue;
+ matched = pred->fn(pred, rec);
+ if (!matched && !pred->or) {
+ and_failed = 1;
+ continue;
+ } else if (matched && pred->or)
+ return 1;
+ } else
+ break;
+ }
+
+ if (and_failed)
+ return 0;
+
+ return 1;
+}
+
+void filter_print_preds(struct filter_pred **preds, struct trace_seq *s)
+{
+ char *field_name;
+ struct filter_pred *pred;
+ int i;
+
+ if (!preds) {
+ trace_seq_printf(s, "none\n");
+ return;
+ }
+
+ for (i = 0; i < MAX_FILTER_PRED; i++) {
+ if (preds[i]) {
+ pred = preds[i];
+ field_name = pred->field_name;
+ if (i)
+ trace_seq_printf(s, pred->or ? "|| " : "&& ");
+ trace_seq_printf(s, "%s ", field_name);
+ trace_seq_printf(s, pred->not ? "!= " : "== ");
+ if (pred->str_val)
+ trace_seq_printf(s, "%s\n", pred->str_val);
+ else
+ trace_seq_printf(s, "%llu\n", pred->val);
+ } else
+ break;
+ }
+}
+
+static struct ftrace_event_field *
+find_event_field(struct ftrace_event_call *call, char *name)
+{
+ struct ftrace_event_field *field;
+
+ list_for_each_entry(field, &call->fields, link) {
+ if (!strcmp(field->name, name))
+ return field;
+ }
+
+ return NULL;
+}
+
+void filter_free_pred(struct filter_pred *pred)
+{
+ if (!pred)
+ return;
+
+ kfree(pred->field_name);
+ kfree(pred->str_val);
+ kfree(pred);
+}
+
+void filter_free_preds(struct ftrace_event_call *call)
+{
+ int i;
+
+ if (call->preds) {
+ for (i = 0; i < MAX_FILTER_PRED; i++)
+ filter_free_pred(call->preds[i]);
+ kfree(call->preds);
+ call->preds = NULL;
+ }
+}
+
+void filter_free_subsystem_preds(struct event_subsystem *system)
+{
+ struct ftrace_event_call *call = __start_ftrace_events;
+ int i;
+
+ if (system->preds) {
+ for (i = 0; i < MAX_FILTER_PRED; i++)
+ filter_free_pred(system->preds[i]);
+ kfree(system->preds);
+ system->preds = NULL;
+ }
+
+ events_for_each(call) {
+ if (!call->name || !call->regfunc)
+ continue;
+
+ if (!strcmp(call->system, system->name))
+ filter_free_preds(call);
+ }
+}
+
+static int __filter_add_pred(struct ftrace_event_call *call,
+ struct filter_pred *pred)
+{
+ int i;
+
+ if (call->preds && !pred->compound)
+ filter_free_preds(call);
+
+ if (!call->preds) {
+ call->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred),
+ GFP_KERNEL);
+ if (!call->preds)
+ return -ENOMEM;
+ }
+
+ for (i = 0; i < MAX_FILTER_PRED; i++) {
+ if (!call->preds[i]) {
+ call->preds[i] = pred;
+ return 0;
+ }
+ }
+
+ return -ENOMEM;
+}
+
+static int is_string_field(const char *type)
+{
+ if (strchr(type, '[') && strstr(type, "char"))
+ return 1;
+
+ return 0;
+}
+
+int filter_add_pred(struct ftrace_event_call *call, struct filter_pred *pred)
+{
+ struct ftrace_event_field *field;
+
+ field = find_event_field(call, pred->field_name);
+ if (!field)
+ return -EINVAL;
+
+ pred->offset = field->offset;
+
+ if (is_string_field(field->type)) {
+ if (!pred->str_val)
+ return -EINVAL;
+ pred->fn = filter_pred_string;
+ pred->str_len = field->size;
+ return __filter_add_pred(call, pred);
+ } else {
+ if (pred->str_val)
+ return -EINVAL;
+ }
+
+ switch (field->size) {
+ case 8:
+ pred->fn = filter_pred_64;
+ break;
+ case 4:
+ pred->fn = filter_pred_32;
+ break;
+ case 2:
+ pred->fn = filter_pred_16;
+ break;
+ case 1:
+ pred->fn = filter_pred_8;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return __filter_add_pred(call, pred);
+}
+
+static struct filter_pred *copy_pred(struct filter_pred *pred)
+{
+ struct filter_pred *new_pred = kmalloc(sizeof(*pred), GFP_KERNEL);
+ if (!new_pred)
+ return NULL;
+
+ memcpy(new_pred, pred, sizeof(*pred));
+
+ if (pred->field_name) {
+ new_pred->field_name = kstrdup(pred->field_name, GFP_KERNEL);
+ if (!new_pred->field_name) {
+ kfree(new_pred);
+ return NULL;
+ }
+ }
+
+ if (pred->str_val) {
+ new_pred->str_val = kstrdup(pred->str_val, GFP_KERNEL);
+ if (!new_pred->str_val) {
+ filter_free_pred(new_pred);
+ return NULL;
+ }
+ }
+
+ return new_pred;
+}
+
+int filter_add_subsystem_pred(struct event_subsystem *system,
+ struct filter_pred *pred)
+{
+ struct ftrace_event_call *call = __start_ftrace_events;
+ struct filter_pred *event_pred;
+ int i;
+
+ if (system->preds && !pred->compound)
+ filter_free_subsystem_preds(system);
+
+ if (!system->preds) {
+ system->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred),
+ GFP_KERNEL);
+ if (!system->preds)
+ return -ENOMEM;
+ }
+
+ for (i = 0; i < MAX_FILTER_PRED; i++) {
+ if (!system->preds[i]) {
+ system->preds[i] = pred;
+ break;
+ }
+ }
+
+ if (i == MAX_FILTER_PRED)
+ return -EINVAL;
+
+ events_for_each(call) {
+ int err;
+
+ if (!call->name || !call->regfunc)
+ continue;
+
+ if (strcmp(call->system, system->name))
+ continue;
+
+ if (!find_event_field(call, pred->field_name))
+ continue;
+
+ event_pred = copy_pred(pred);
+ if (!event_pred)
+ goto oom;
+
+ err = filter_add_pred(call, event_pred);
+ if (err)
+ filter_free_pred(event_pred);
+ if (err == -ENOMEM)
+ goto oom;
+ }
+
+ return 0;
+
+oom:
+ system->preds[i] = NULL;
+ return -ENOMEM;
+}
+
+int filter_parse(char **pbuf, struct filter_pred *pred)
+{
+ char *tmp, *tok, *val_str = NULL;
+ int tok_n = 0;
+
+ /* field ==/!= number, or/and field ==/!= number, number */
+ while ((tok = strsep(pbuf, " \n"))) {
+ if (tok_n == 0) {
+ if (!strcmp(tok, "0")) {
+ pred->clear = 1;
+ return 0;
+ } else if (!strcmp(tok, "&&")) {
+ pred->or = 0;
+ pred->compound = 1;
+ } else if (!strcmp(tok, "||")) {
+ pred->or = 1;
+ pred->compound = 1;
+ } else
+ pred->field_name = tok;
+ tok_n = 1;
+ continue;
+ }
+ if (tok_n == 1) {
+ if (!pred->field_name)
+ pred->field_name = tok;
+ else if (!strcmp(tok, "!="))
+ pred->not = 1;
+ else if (!strcmp(tok, "=="))
+ pred->not = 0;
+ else {
+ pred->field_name = NULL;
+ return -EINVAL;
+ }
+ tok_n = 2;
+ continue;
+ }
+ if (tok_n == 2) {
+ if (pred->compound) {
+ if (!strcmp(tok, "!="))
+ pred->not = 1;
+ else if (!strcmp(tok, "=="))
+ pred->not = 0;
+ else {
+ pred->field_name = NULL;
+ return -EINVAL;
+ }
+ } else {
+ val_str = tok;
+ break; /* done */
+ }
+ tok_n = 3;
+ continue;
+ }
+ if (tok_n == 3) {
+ val_str = tok;
+ break; /* done */
+ }
+ }
+
+ pred->field_name = kstrdup(pred->field_name, GFP_KERNEL);
+ if (!pred->field_name)
+ return -ENOMEM;
+
+ pred->val = simple_strtoull(val_str, &tmp, 10);
+ if (tmp == val_str) {
+ pred->str_val = kstrdup(val_str, GFP_KERNEL);
+ if (!pred->str_val)
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+
projects / linux-2.6-omap-h63xx.git / blobdiff