* 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 <linux/mutex.h>
#include "trace.h"
#include "trace_output.h"
-static DEFINE_MUTEX(filter_mutex);
-
enum filter_op_ids
{
OP_OR,
} operand;
};
+#define DEFINE_COMPARISON_PRED(type) \
+static int filter_pred_##type(struct filter_pred *pred, void *event, \
+ int val1, int val2) \
+{ \
+ type *addr = (type *)(event + pred->offset); \
+ type val = (type)pred->val; \
+ int match = 0; \
+ \
+ switch (pred->op) { \
+ case OP_LT: \
+ match = (*addr < val); \
+ break; \
+ case OP_LE: \
+ match = (*addr <= val); \
+ break; \
+ case OP_GT: \
+ match = (*addr > val); \
+ break; \
+ case OP_GE: \
+ match = (*addr >= val); \
+ break; \
+ default: \
+ break; \
+ } \
+ \
+ return match; \
+}
+
+#define DEFINE_EQUALITY_PRED(size) \
+static int filter_pred_##size(struct filter_pred *pred, void *event, \
+ int val1, int val2) \
+{ \
+ u##size *addr = (u##size *)(event + pred->offset); \
+ u##size val = (u##size)pred->val; \
+ int match; \
+ \
+ match = (val == *addr) ^ pred->not; \
+ \
+ return match; \
+}
+
DEFINE_COMPARISON_PRED(s64);
DEFINE_COMPARISON_PRED(u64);
DEFINE_COMPARISON_PRED(s32);
return val1 || val2;
}
+/* Filter predicate for fixed sized arrays of characters */
static int filter_pred_string(struct filter_pred *pred, void *event,
int val1, int val2)
{
char *addr = (char *)(event + pred->offset);
int cmp, match;
- cmp = strncmp(addr, pred->str_val, pred->str_len);
+ cmp = pred->regex.match(addr, &pred->regex, pred->regex.field_len);
+
+ match = cmp ^ pred->not;
+
+ return match;
+}
+
+/* Filter predicate for char * pointers */
+static int filter_pred_pchar(struct filter_pred *pred, void *event,
+ int val1, int val2)
+{
+ char **addr = (char **)(event + pred->offset);
+ int cmp, match;
+
+ cmp = pred->regex.match(*addr, &pred->regex, pred->regex.field_len);
+
+ match = cmp ^ pred->not;
+
+ return match;
+}
+
+/*
+ * Filter predicate for dynamic sized arrays of characters.
+ * These are implemented through a list of strings at the end
+ * of the entry.
+ * Also each of these strings have a field in the entry which
+ * contains its offset from the beginning of the entry.
+ * We have then first to get this field, dereference it
+ * and add it to the address of the entry, and at last we have
+ * the address of the string.
+ */
+static int filter_pred_strloc(struct filter_pred *pred, void *event,
+ int val1, int val2)
+{
+ u32 str_item = *(u32 *)(event + pred->offset);
+ int str_loc = str_item & 0xffff;
+ int str_len = str_item >> 16;
+ char *addr = (char *)(event + str_loc);
+ int cmp, match;
+
+ cmp = pred->regex.match(addr, &pred->regex, str_len);
- match = (!cmp) ^ pred->not;
+ match = cmp ^ pred->not;
return match;
}
return 0;
}
+/* Basic regex callbacks */
+static int regex_match_full(char *str, struct regex *r, int len)
+{
+ if (strncmp(str, r->pattern, len) == 0)
+ return 1;
+ return 0;
+}
+
+static int regex_match_front(char *str, struct regex *r, int len)
+{
+ if (strncmp(str, r->pattern, len) == 0)
+ return 1;
+ return 0;
+}
+
+static int regex_match_middle(char *str, struct regex *r, int len)
+{
+ if (strstr(str, r->pattern))
+ return 1;
+ return 0;
+}
+
+static int regex_match_end(char *str, struct regex *r, int len)
+{
+ char *ptr = strstr(str, r->pattern);
+
+ if (ptr && (ptr[r->len] == 0))
+ return 1;
+ return 0;
+}
+
+enum regex_type {
+ MATCH_FULL,
+ MATCH_FRONT_ONLY,
+ MATCH_MIDDLE_ONLY,
+ MATCH_END_ONLY,
+};
+
+/*
+ * Pass in a buffer containing a regex and this function will
+ * set search to point to the search part of the buffer and
+ * return the type of search it is (see enum above).
+ * This does modify buff.
+ *
+ * Returns enum type.
+ * search returns the pointer to use for comparison.
+ * not returns 1 if buff started with a '!'
+ * 0 otherwise.
+ */
+static enum regex_type
+filter_parse_regex(char *buff, int len, char **search, int *not)
+{
+ int type = MATCH_FULL;
+ int i;
+
+ if (buff[0] == '!') {
+ *not = 1;
+ buff++;
+ len--;
+ } else
+ *not = 0;
+
+ *search = buff;
+
+ for (i = 0; i < len; i++) {
+ if (buff[i] == '*') {
+ if (!i) {
+ *search = buff + 1;
+ type = MATCH_END_ONLY;
+ } else {
+ if (type == MATCH_END_ONLY)
+ type = MATCH_MIDDLE_ONLY;
+ else
+ type = MATCH_FRONT_ONLY;
+ buff[i] = 0;
+ break;
+ }
+ }
+ }
+
+ return type;
+}
+
+static int filter_build_regex(struct filter_pred *pred)
+{
+ struct regex *r = &pred->regex;
+ char *search, *dup;
+ enum regex_type type;
+ int not;
+
+ type = filter_parse_regex(r->pattern, r->len, &search, ¬);
+ dup = kstrdup(search, GFP_KERNEL);
+ if (!dup)
+ return -ENOMEM;
+
+ strcpy(r->pattern, dup);
+ kfree(dup);
+
+ r->len = strlen(r->pattern);
+
+ switch (type) {
+ case MATCH_FULL:
+ r->match = regex_match_full;
+ break;
+ case MATCH_FRONT_ONLY:
+ r->match = regex_match_front;
+ break;
+ case MATCH_MIDDLE_ONLY:
+ r->match = regex_match_middle;
+ break;
+ case MATCH_END_ONLY:
+ r->match = regex_match_end;
+ break;
+ }
+
+ pred->not ^= not;
+
+ return 0;
+}
+
/* return 1 if event matches, 0 otherwise (discard) */
int filter_match_preds(struct ftrace_event_call *call, void *rec)
{
{
struct event_filter *filter = call->filter;
- mutex_lock(&filter_mutex);
- if (filter->filter_string)
+ mutex_lock(&event_mutex);
+ if (filter && filter->filter_string)
trace_seq_printf(s, "%s\n", filter->filter_string);
else
trace_seq_printf(s, "none\n");
- mutex_unlock(&filter_mutex);
+ mutex_unlock(&event_mutex);
}
void print_subsystem_event_filter(struct event_subsystem *system,
{
struct event_filter *filter = system->filter;
- mutex_lock(&filter_mutex);
- if (filter->filter_string)
+ mutex_lock(&event_mutex);
+ if (filter && filter->filter_string)
trace_seq_printf(s, "%s\n", filter->filter_string);
else
trace_seq_printf(s, "none\n");
- mutex_unlock(&filter_mutex);
+ mutex_unlock(&event_mutex);
}
static struct ftrace_event_field *
{
kfree(pred->field_name);
pred->field_name = NULL;
- pred->str_len = 0;
+ pred->regex.len = 0;
}
static int filter_set_pred(struct filter_pred *dest,
struct event_filter *filter = call->filter;
int i;
+ if (!filter)
+ return;
+
for (i = 0; i < MAX_FILTER_PRED; i++) {
if (filter->preds[i])
filter_free_pred(filter->preds[i]);
}
kfree(filter->preds);
+ kfree(filter->filter_string);
kfree(filter);
call->filter = NULL;
}
-int init_preds(struct ftrace_event_call *call)
+static int init_preds(struct ftrace_event_call *call)
{
struct event_filter *filter;
struct filter_pred *pred;
int i;
+ if (call->filter)
+ return 0;
+
filter = call->filter = kzalloc(sizeof(*filter), GFP_KERNEL);
if (!call->filter)
return -ENOMEM;
- call->filter_active = 0;
filter->n_preds = 0;
filter->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred), GFP_KERNEL);
return -ENOMEM;
}
-EXPORT_SYMBOL_GPL(init_preds);
-static void filter_free_subsystem_preds(struct event_subsystem *system)
+static int init_subsystem_preds(struct event_subsystem *system)
{
- struct event_filter *filter = system->filter;
struct ftrace_event_call *call;
- int i;
+ int err;
- if (filter->n_preds) {
- for (i = 0; i < filter->n_preds; i++)
- filter_free_pred(filter->preds[i]);
- kfree(filter->preds);
- filter->preds = NULL;
- filter->n_preds = 0;
+ list_for_each_entry(call, &ftrace_events, list) {
+ if (!call->define_fields)
+ continue;
+
+ if (strcmp(call->system, system->name) != 0)
+ continue;
+
+ err = init_preds(call);
+ if (err)
+ return err;
}
+ 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)
+{
+ struct ftrace_event_call *call;
+
list_for_each_entry(call, &ftrace_events, list) {
if (!call->define_fields)
continue;
- if (!strcmp(call->system, system->name)) {
- filter_disable_preds(call);
- remove_filter_string(call->filter);
+ 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);
}
}
return 0;
}
-static int is_string_field(const char *type)
+int filter_assign_type(const char *type)
{
+ if (strstr(type, "__data_loc") && strstr(type, "char"))
+ return FILTER_DYN_STRING;
+
if (strchr(type, '[') && strstr(type, "char"))
- return 1;
+ return FILTER_STATIC_STRING;
- return 0;
+ return FILTER_OTHER;
+}
+
+static bool is_string_field(struct ftrace_event_field *field)
+{
+ return field->filter_type == FILTER_DYN_STRING ||
+ field->filter_type == FILTER_STATIC_STRING ||
+ field->filter_type == FILTER_PTR_STRING;
}
static int is_legal_op(struct ftrace_event_field *field, int op)
{
- if (is_string_field(field->type) && (op != OP_EQ && op != OP_NE))
+ if (is_string_field(field) && (op != OP_EQ && op != OP_NE))
return 0;
return 1;
static int filter_add_pred(struct filter_parse_state *ps,
struct ftrace_event_call *call,
- struct filter_pred *pred)
+ struct filter_pred *pred,
+ bool dry_run)
{
struct ftrace_event_field *field;
filter_pred_fn_t fn;
unsigned long long val;
+ int ret;
pred->fn = filter_pred_none;
if (pred->op == OP_AND) {
pred->pop_n = 2;
- return filter_add_pred_fn(ps, call, pred, filter_pred_and);
+ fn = filter_pred_and;
+ goto add_pred_fn;
} else if (pred->op == OP_OR) {
pred->pop_n = 2;
- return filter_add_pred_fn(ps, call, pred, filter_pred_or);
+ fn = filter_pred_or;
+ goto add_pred_fn;
}
field = find_event_field(call, pred->field_name);
return -EINVAL;
}
- if (is_string_field(field->type)) {
- fn = filter_pred_string;
- pred->str_len = field->size;
- if (pred->op == OP_NE)
- pred->not = 1;
- return filter_add_pred_fn(ps, call, pred, fn);
+ if (is_string_field(field)) {
+ ret = filter_build_regex(pred);
+ if (ret)
+ return ret;
+
+ if (field->filter_type == FILTER_STATIC_STRING) {
+ fn = filter_pred_string;
+ pred->regex.field_len = field->size;
+ } else if (field->filter_type == FILTER_DYN_STRING)
+ fn = filter_pred_strloc;
+ else {
+ fn = filter_pred_pchar;
+ pred->regex.field_len = strlen(pred->regex.pattern);
+ }
} else {
- if (strict_strtoull(pred->str_val, 0, &val)) {
+ if (field->is_signed)
+ ret = strict_strtoll(pred->regex.pattern, 0, &val);
+ else
+ ret = strict_strtoull(pred->regex.pattern, 0, &val);
+ if (ret) {
parse_error(ps, FILT_ERR_ILLEGAL_INTVAL, 0);
return -EINVAL;
}
pred->val = val;
- }
- fn = select_comparison_fn(pred->op, field->size, field->is_signed);
- if (!fn) {
- parse_error(ps, FILT_ERR_INVALID_OP, 0);
- return -EINVAL;
+ fn = select_comparison_fn(pred->op, field->size,
+ field->is_signed);
+ if (!fn) {
+ parse_error(ps, FILT_ERR_INVALID_OP, 0);
+ return -EINVAL;
+ }
}
if (pred->op == OP_NE)
pred->not = 1;
- return filter_add_pred_fn(ps, call, pred, fn);
+add_pred_fn:
+ if (!dry_run)
+ return filter_add_pred_fn(ps, call, 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)
+ char *filter_string,
+ bool dry_run)
{
- struct event_filter *filter = system->filter;
struct ftrace_event_call *call;
-
- if (!filter->preds) {
- filter->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred),
- GFP_KERNEL);
-
- if (!filter->preds)
- return -ENOMEM;
- }
-
- if (filter->n_preds == MAX_FILTER_PRED) {
- parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0);
- return -ENOSPC;
- }
-
- filter->preds[filter->n_preds] = pred;
- filter->n_preds++;
+ int err = 0;
+ bool fail = true;
list_for_each_entry(call, &ftrace_events, list) {
- int err;
if (!call->define_fields)
continue;
if (strcmp(call->system, system->name))
continue;
- err = filter_add_pred(ps, call, pred);
- if (err) {
- filter_free_subsystem_preds(system);
- parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0);
- return err;
- }
- replace_filter_string(call->filter, filter_string);
+ 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 inline int append_operand_char(struct filter_parse_state *ps, char c)
{
- if (ps->operand.tail == MAX_FILTER_STR_VAL)
+ if (ps->operand.tail == MAX_FILTER_STR_VAL - 1)
return -EINVAL;
ps->operand.string[ps->operand.tail++] = c;
static int filter_parse(struct filter_parse_state *ps)
{
+ int in_string = 0;
int op, top_op;
char ch;
while ((ch = infix_next(ps))) {
+ if (ch == '"') {
+ in_string ^= 1;
+ continue;
+ }
+
+ if (in_string)
+ goto parse_operand;
+
if (isspace(ch))
continue;
}
continue;
}
+parse_operand:
if (append_operand_char(ps, ch)) {
parse_error(ps, FILT_ERR_OPERAND_TOO_LONG, 0);
return -EINVAL;
return NULL;
}
- strcpy(pred->str_val, operand2);
- pred->str_len = strlen(operand2);
+ strcpy(pred->regex.pattern, operand2);
+ pred->regex.len = strlen(pred->regex.pattern);
pred->op = op;
static int replace_preds(struct event_subsystem *system,
struct ftrace_event_call *call,
struct filter_parse_state *ps,
- char *filter_string)
+ char *filter_string,
+ bool dry_run)
{
char *operand1 = NULL, *operand2 = NULL;
struct filter_pred *pred;
struct postfix_elt *elt;
int err;
+ int n_preds = 0;
err = check_preds(ps);
if (err)
continue;
}
+ if (n_preds++ == MAX_FILTER_PRED) {
+ parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0);
+ return -ENOSPC;
+ }
+
if (elt->op == OP_AND || elt->op == OP_OR) {
pred = create_logical_pred(elt->op);
- if (call) {
- err = filter_add_pred(ps, call, pred);
- filter_free_pred(pred);
- } else
- err = filter_add_subsystem_pred(ps, system,
- pred, filter_string);
- if (err)
- return err;
-
- operand1 = operand2 = NULL;
- continue;
+ goto add_pred;
}
if (!operand1 || !operand2) {
}
pred = create_pred(elt->op, operand1, operand2);
- if (call) {
- err = filter_add_pred(ps, call, pred);
- filter_free_pred(pred);
- } else
+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);
+ filter_string, dry_run);
+ filter_free_pred(pred);
if (err)
return err;
struct filter_parse_state *ps;
- mutex_lock(&filter_mutex);
+ mutex_lock(&event_mutex);
+
+ err = init_preds(call);
+ if (err)
+ goto out_unlock;
if (!strcmp(strstrip(filter_string), "0")) {
filter_disable_preds(call);
remove_filter_string(call->filter);
- mutex_unlock(&filter_mutex);
+ mutex_unlock(&event_mutex);
return 0;
}
+ err = -ENOMEM;
ps = kzalloc(sizeof(*ps), GFP_KERNEL);
if (!ps)
- return -ENOMEM;
+ goto out_unlock;
filter_disable_preds(call);
replace_filter_string(call->filter, filter_string);
goto out;
}
- err = replace_preds(NULL, call, ps, filter_string);
+ err = replace_preds(NULL, call, ps, filter_string, false);
if (err)
append_filter_err(ps, call->filter);
filter_opstack_clear(ps);
postfix_clear(ps);
kfree(ps);
-
- mutex_unlock(&filter_mutex);
+out_unlock:
+ mutex_unlock(&event_mutex);
return err;
}
struct filter_parse_state *ps;
- mutex_lock(&filter_mutex);
+ mutex_lock(&event_mutex);
+
+ err = init_subsystem_preds(system);
+ if (err)
+ goto out_unlock;
if (!strcmp(strstrip(filter_string), "0")) {
- filter_free_subsystem_preds(system);
+ filter_free_subsystem_preds(system, FILTER_DISABLE_ALL);
remove_filter_string(system->filter);
- mutex_unlock(&filter_mutex);
+ mutex_unlock(&event_mutex);
return 0;
}
+ err = -ENOMEM;
ps = kzalloc(sizeof(*ps), GFP_KERNEL);
if (!ps)
- return -ENOMEM;
+ goto out_unlock;
- filter_free_subsystem_preds(system);
replace_filter_string(system->filter, filter_string);
parse_init(ps, filter_ops, filter_string);
goto out;
}
- err = replace_preds(system, NULL, ps, filter_string);
- if (err)
+ 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) {
append_filter_err(ps, system->filter);
+ filter_free_subsystem_preds(system, 2);
+ }
out:
filter_opstack_clear(ps);
postfix_clear(ps);
kfree(ps);
-
- mutex_unlock(&filter_mutex);
+out_unlock:
+ mutex_unlock(&event_mutex);
return err;
}
Code Review / linux-2.6.git / blobdiff