* 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 <linux/perf_event.h>
#include "trace.h"
#include "trace_output.h"
-static int filter_pred_64(struct filter_pred *pred, void *event)
+enum filter_op_ids
{
- u64 *addr = (u64 *)(event + pred->offset);
- u64 val = (u64)pred->val;
- int match;
+ OP_OR,
+ OP_AND,
+ OP_GLOB,
+ OP_NE,
+ OP_EQ,
+ OP_LT,
+ OP_LE,
+ OP_GT,
+ OP_GE,
+ OP_NONE,
+ OP_OPEN_PAREN,
+};
+
+struct filter_op {
+ int id;
+ char *string;
+ int precedence;
+};
+
+static struct filter_op filter_ops[] = {
+ { OP_OR, "||", 1 },
+ { OP_AND, "&&", 2 },
+ { OP_GLOB, "~", 4 },
+ { OP_NE, "!=", 4 },
+ { OP_EQ, "==", 4 },
+ { OP_LT, "<", 5 },
+ { OP_LE, "<=", 5 },
+ { OP_GT, ">", 5 },
+ { OP_GE, ">=", 5 },
+ { OP_NONE, "OP_NONE", 0 },
+ { OP_OPEN_PAREN, "(", 0 },
+};
+
+enum {
+ FILT_ERR_NONE,
+ FILT_ERR_INVALID_OP,
+ FILT_ERR_UNBALANCED_PAREN,
+ FILT_ERR_TOO_MANY_OPERANDS,
+ FILT_ERR_OPERAND_TOO_LONG,
+ FILT_ERR_FIELD_NOT_FOUND,
+ FILT_ERR_ILLEGAL_FIELD_OP,
+ FILT_ERR_ILLEGAL_INTVAL,
+ FILT_ERR_BAD_SUBSYS_FILTER,
+ FILT_ERR_TOO_MANY_PREDS,
+ FILT_ERR_MISSING_FIELD,
+ FILT_ERR_INVALID_FILTER,
+};
+
+static char *err_text[] = {
+ "No error",
+ "Invalid operator",
+ "Unbalanced parens",
+ "Too many operands",
+ "Operand too long",
+ "Field not found",
+ "Illegal operation for field type",
+ "Illegal integer value",
+ "Couldn't find or set field in one of a subsystem's events",
+ "Too many terms in predicate expression",
+ "Missing field name and/or value",
+ "Meaningless filter expression",
+};
+
+struct opstack_op {
+ int op;
+ struct list_head list;
+};
+
+struct postfix_elt {
+ int op;
+ char *operand;
+ struct list_head list;
+};
+
+struct filter_parse_state {
+ struct filter_op *ops;
+ struct list_head opstack;
+ struct list_head postfix;
+ int lasterr;
+ int lasterr_pos;
+
+ struct {
+ char *string;
+ unsigned int cnt;
+ unsigned int tail;
+ } infix;
+
+ struct {
+ char string[MAX_FILTER_STR_VAL];
+ int pos;
+ unsigned int tail;
+ } 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; \
+}
- match = (val == *addr) ^ pred->not;
+#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; \
+}
- return match;
+DEFINE_COMPARISON_PRED(s64);
+DEFINE_COMPARISON_PRED(u64);
+DEFINE_COMPARISON_PRED(s32);
+DEFINE_COMPARISON_PRED(u32);
+DEFINE_COMPARISON_PRED(s16);
+DEFINE_COMPARISON_PRED(u16);
+DEFINE_COMPARISON_PRED(s8);
+DEFINE_COMPARISON_PRED(u8);
+
+DEFINE_EQUALITY_PRED(64);
+DEFINE_EQUALITY_PRED(32);
+DEFINE_EQUALITY_PRED(16);
+DEFINE_EQUALITY_PRED(8);
+
+static int filter_pred_and(struct filter_pred *pred __attribute((unused)),
+ void *event __attribute((unused)),
+ int val1, int val2)
+{
+ return val1 && val2;
}
-static int filter_pred_32(struct filter_pred *pred, void *event)
+static int filter_pred_or(struct filter_pred *pred __attribute((unused)),
+ void *event __attribute((unused)),
+ int val1, int val2)
{
- u32 *addr = (u32 *)(event + pred->offset);
- u32 val = (u32)pred->val;
- int match;
+ return val1 || val2;
+}
- match = (val == *addr) ^ pred->not;
+/* 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 = pred->regex.match(addr, &pred->regex, pred->regex.field_len);
+
+ match = cmp ^ pred->not;
return match;
}
-static int filter_pred_16(struct filter_pred *pred, void *event)
+/* Filter predicate for char * pointers */
+static int filter_pred_pchar(struct filter_pred *pred, void *event,
+ int val1, int val2)
{
- u16 *addr = (u16 *)(event + pred->offset);
- u16 val = (u16)pred->val;
- int match;
+ char **addr = (char **)(event + pred->offset);
+ int cmp, match;
+ int len = strlen(*addr) + 1; /* including tailing '\0' */
+
+ cmp = pred->regex.match(*addr, &pred->regex, len);
- match = (val == *addr) ^ pred->not;
+ match = cmp ^ pred->not;
return match;
}
-static int filter_pred_8(struct filter_pred *pred, void *event)
+/*
+ * 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)
{
- u8 *addr = (u8 *)(event + pred->offset);
- u8 val = (u8)pred->val;
- int match;
+ 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;
- match = (val == *addr) ^ pred->not;
+ cmp = pred->regex.match(addr, &pred->regex, str_len);
+
+ match = cmp ^ pred->not;
return match;
}
-static int filter_pred_string(struct filter_pred *pred, void *event)
+static int filter_pred_none(struct filter_pred *pred, void *event,
+ int val1, int val2)
{
- char *addr = (char *)(event + pred->offset);
- int cmp, match;
+ return 0;
+}
- cmp = strncmp(addr, pred->str_val, pred->str_len);
+/* 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;
+}
- match = (!cmp) ^ pred->not;
+static int regex_match_front(char *str, struct regex *r, int len)
+{
+ if (strncmp(str, r->pattern, r->len) == 0)
+ return 1;
+ return 0;
+}
- return match;
+static int regex_match_middle(char *str, struct regex *r, int len)
+{
+ if (strnstr(str, r->pattern, len))
+ return 1;
+ return 0;
}
-/* return 1 if event matches, 0 otherwise (discard) */
-int filter_match_preds(struct ftrace_event_call *call, void *rec)
+static int regex_match_end(char *str, struct regex *r, int len)
{
- int i, matched, and_failed = 0;
- struct filter_pred *pred;
+ int strlen = len - 1;
- 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 (strlen >= r->len &&
+ memcmp(str + strlen - r->len, r->pattern, r->len) == 0)
+ return 1;
+ return 0;
+}
+
+/**
+ * filter_parse_regex - parse a basic regex
+ * @buff: the raw regex
+ * @len: length of the regex
+ * @search: will point to the beginning of the string to compare
+ * @not: tell whether the match will have to be inverted
+ *
+ * This passes 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.
+ */
+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;
+ }
+ }
}
- if (and_failed)
- return 0;
+ return type;
+}
- return 1;
+static void filter_build_regex(struct filter_pred *pred)
+{
+ struct regex *r = &pred->regex;
+ char *search;
+ enum regex_type type = MATCH_FULL;
+ int not = 0;
+
+ if (pred->op == OP_GLOB) {
+ type = filter_parse_regex(r->pattern, r->len, &search, ¬);
+ r->len = strlen(search);
+ memmove(r->pattern, search, r->len+1);
+ }
+
+ 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;
}
-void filter_print_preds(struct filter_pred **preds, struct trace_seq *s)
+/* return 1 if event matches, 0 otherwise (discard) */
+int filter_match_preds(struct event_filter *filter, void *rec)
{
- char *field_name;
+ int match, top = 0, val1 = 0, val2 = 0;
+ int stack[MAX_FILTER_PRED];
struct filter_pred *pred;
int i;
- if (!preds) {
- trace_seq_printf(s, "none\n");
- return;
+ for (i = 0; i < filter->n_preds; i++) {
+ pred = filter->preds[i];
+ if (!pred->pop_n) {
+ match = pred->fn(pred, rec, val1, val2);
+ stack[top++] = match;
+ continue;
+ }
+ if (pred->pop_n > top) {
+ WARN_ON_ONCE(1);
+ return 0;
+ }
+ val1 = stack[--top];
+ val2 = stack[--top];
+ match = pred->fn(pred, rec, val1, val2);
+ stack[top++] = match;
}
- 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;
- }
+ return stack[--top];
+}
+EXPORT_SYMBOL_GPL(filter_match_preds);
+
+static void parse_error(struct filter_parse_state *ps, int err, int pos)
+{
+ ps->lasterr = err;
+ ps->lasterr_pos = pos;
+}
+
+static void remove_filter_string(struct event_filter *filter)
+{
+ kfree(filter->filter_string);
+ filter->filter_string = NULL;
+}
+
+static int replace_filter_string(struct event_filter *filter,
+ char *filter_string)
+{
+ kfree(filter->filter_string);
+ filter->filter_string = kstrdup(filter_string, GFP_KERNEL);
+ if (!filter->filter_string)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static int append_filter_string(struct event_filter *filter,
+ char *string)
+{
+ int newlen;
+ char *new_filter_string;
+
+ BUG_ON(!filter->filter_string);
+ newlen = strlen(filter->filter_string) + strlen(string) + 1;
+ new_filter_string = kmalloc(newlen, GFP_KERNEL);
+ if (!new_filter_string)
+ return -ENOMEM;
+
+ strcpy(new_filter_string, filter->filter_string);
+ strcat(new_filter_string, string);
+ kfree(filter->filter_string);
+ filter->filter_string = new_filter_string;
+
+ return 0;
+}
+
+static void append_filter_err(struct filter_parse_state *ps,
+ struct event_filter *filter)
+{
+ int pos = ps->lasterr_pos;
+ char *buf, *pbuf;
+
+ buf = (char *)__get_free_page(GFP_TEMPORARY);
+ if (!buf)
+ return;
+
+ append_filter_string(filter, "\n");
+ memset(buf, ' ', PAGE_SIZE);
+ if (pos > PAGE_SIZE - 128)
+ pos = 0;
+ buf[pos] = '^';
+ pbuf = &buf[pos] + 1;
+
+ sprintf(pbuf, "\nparse_error: %s\n", err_text[ps->lasterr]);
+ append_filter_string(filter, buf);
+ free_page((unsigned long) buf);
+}
+
+void print_event_filter(struct ftrace_event_call *call, struct trace_seq *s)
+{
+ struct event_filter *filter = call->filter;
+
+ 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(&event_mutex);
+}
+
+void print_subsystem_event_filter(struct event_subsystem *system,
+ struct trace_seq *s)
+{
+ struct event_filter *filter = system->filter;
+
+ 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(&event_mutex);
}
static struct ftrace_event_field *
return NULL;
}
-void filter_free_pred(struct filter_pred *pred)
+static 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)
+static void filter_clear_pred(struct filter_pred *pred)
{
+ kfree(pred->field_name);
+ pred->field_name = NULL;
+ pred->regex.len = 0;
+}
+
+static int filter_set_pred(struct filter_pred *dest,
+ struct filter_pred *src,
+ filter_pred_fn_t fn)
+{
+ *dest = *src;
+ if (src->field_name) {
+ dest->field_name = kstrdup(src->field_name, GFP_KERNEL);
+ if (!dest->field_name)
+ return -ENOMEM;
+ }
+ dest->fn = fn;
+
+ return 0;
+}
+
+static void filter_disable_preds(struct ftrace_event_call *call)
+{
+ struct event_filter *filter = call->filter;
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;
+ call->filter_active = 0;
+ filter->n_preds = 0;
+
+ for (i = 0; i < MAX_FILTER_PRED; i++)
+ filter->preds[i]->fn = filter_pred_none;
+}
+
+static void __free_preds(struct event_filter *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);
}
-void filter_free_subsystem_preds(struct event_subsystem *system)
+void destroy_preds(struct ftrace_event_call *call)
{
- struct ftrace_event_call *call = __start_ftrace_events;
+ __free_preds(call->filter);
+ call->filter = NULL;
+ call->filter_active = 0;
+}
+
+static struct event_filter *__alloc_preds(void)
+{
+ struct event_filter *filter;
+ struct filter_pred *pred;
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;
+ filter = kzalloc(sizeof(*filter), GFP_KERNEL);
+ if (!filter)
+ return ERR_PTR(-ENOMEM);
+
+ filter->n_preds = 0;
+
+ filter->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred), GFP_KERNEL);
+ if (!filter->preds)
+ goto oom;
+
+ for (i = 0; i < MAX_FILTER_PRED; i++) {
+ pred = kzalloc(sizeof(*pred), GFP_KERNEL);
+ if (!pred)
+ goto oom;
+ pred->fn = filter_pred_none;
+ filter->preds[i] = pred;
}
- events_for_each(call) {
- if (!call->name || !call->regfunc)
+ return filter;
+
+oom:
+ __free_preds(filter);
+ return ERR_PTR(-ENOMEM);
+}
+
+static int init_preds(struct ftrace_event_call *call)
+{
+ if (call->filter)
+ return 0;
+
+ call->filter_active = 0;
+ call->filter = __alloc_preds();
+ if (IS_ERR(call->filter))
+ return PTR_ERR(call->filter);
+
+ return 0;
+}
+
+static int init_subsystem_preds(struct event_subsystem *system)
+{
+ struct ftrace_event_call *call;
+ int err;
+
+ list_for_each_entry(call, &ftrace_events, list) {
+ if (!call->define_fields)
+ continue;
+
+ if (strcmp(call->system, system->name) != 0)
continue;
- if (!strcmp(call->system, system->name))
- filter_free_preds(call);
+ err = init_preds(call);
+ if (err)
+ return err;
}
+
+ return 0;
}
-static int __filter_add_pred(struct ftrace_event_call *call,
- struct filter_pred *pred)
+static void filter_free_subsystem_preds(struct event_subsystem *system)
{
- int i;
+ struct ftrace_event_call *call;
- if (call->preds && !pred->compound)
- filter_free_preds(call);
+ list_for_each_entry(call, &ftrace_events, list) {
+ if (!call->define_fields)
+ continue;
- if (!call->preds) {
- call->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred),
- GFP_KERNEL);
- if (!call->preds)
- return -ENOMEM;
+ if (strcmp(call->system, system->name) != 0)
+ continue;
+
+ filter_disable_preds(call);
+ remove_filter_string(call->filter);
}
+}
- for (i = 0; i < MAX_FILTER_PRED; i++) {
- if (!call->preds[i]) {
- call->preds[i] = pred;
- return 0;
- }
+static int filter_add_pred_fn(struct filter_parse_state *ps,
+ struct ftrace_event_call *call,
+ struct event_filter *filter,
+ struct filter_pred *pred,
+ filter_pred_fn_t fn)
+{
+ int idx, err;
+
+ if (filter->n_preds == MAX_FILTER_PRED) {
+ parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0);
+ return -ENOSPC;
}
- return -ENOMEM;
+ idx = filter->n_preds;
+ filter_clear_pred(filter->preds[idx]);
+ err = filter_set_pred(filter->preds[idx], pred, fn);
+ if (err)
+ return err;
+
+ filter->n_preds++;
+
+ 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;
}
-int filter_add_pred(struct ftrace_event_call *call, struct filter_pred *pred)
+static bool is_string_field(struct ftrace_event_field *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;
+}
- field = find_event_field(call, pred->field_name);
- if (!field)
- return -EINVAL;
+static int is_legal_op(struct ftrace_event_field *field, int op)
+{
+ if (is_string_field(field) &&
+ (op != OP_EQ && op != OP_NE && op != OP_GLOB))
+ return 0;
+ if (!is_string_field(field) && op == OP_GLOB)
+ return 0;
- pred->offset = field->offset;
+ return 1;
+}
- 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;
- }
+static filter_pred_fn_t select_comparison_fn(int op, int field_size,
+ int field_is_signed)
+{
+ filter_pred_fn_t fn = NULL;
- switch (field->size) {
+ switch (field_size) {
case 8:
- pred->fn = filter_pred_64;
+ if (op == OP_EQ || op == OP_NE)
+ fn = filter_pred_64;
+ else if (field_is_signed)
+ fn = filter_pred_s64;
+ else
+ fn = filter_pred_u64;
break;
case 4:
- pred->fn = filter_pred_32;
+ if (op == OP_EQ || op == OP_NE)
+ fn = filter_pred_32;
+ else if (field_is_signed)
+ fn = filter_pred_s32;
+ else
+ fn = filter_pred_u32;
break;
case 2:
- pred->fn = filter_pred_16;
+ if (op == OP_EQ || op == OP_NE)
+ fn = filter_pred_16;
+ else if (field_is_signed)
+ fn = filter_pred_s16;
+ else
+ fn = filter_pred_u16;
break;
case 1:
- pred->fn = filter_pred_8;
+ if (op == OP_EQ || op == OP_NE)
+ fn = filter_pred_8;
+ else if (field_is_signed)
+ fn = filter_pred_s8;
+ else
+ fn = filter_pred_u8;
break;
- default:
- return -EINVAL;
}
- return __filter_add_pred(call, pred);
+ return fn;
}
-static struct filter_pred *copy_pred(struct filter_pred *pred)
+static int filter_add_pred(struct filter_parse_state *ps,
+ struct ftrace_event_call *call,
+ struct event_filter *filter,
+ struct filter_pred *pred,
+ bool dry_run)
{
- struct filter_pred *new_pred = kmalloc(sizeof(*pred), GFP_KERNEL);
- if (!new_pred)
- return NULL;
+ 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;
+ fn = filter_pred_and;
+ goto add_pred_fn;
+ } else if (pred->op == OP_OR) {
+ pred->pop_n = 2;
+ fn = filter_pred_or;
+ goto add_pred_fn;
+ }
+
+ field = find_event_field(call, pred->field_name);
+ if (!field) {
+ parse_error(ps, FILT_ERR_FIELD_NOT_FOUND, 0);
+ return -EINVAL;
+ }
- memcpy(new_pred, pred, sizeof(*pred));
+ pred->offset = field->offset;
- 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 (!is_legal_op(field, pred->op)) {
+ parse_error(ps, FILT_ERR_ILLEGAL_FIELD_OP, 0);
+ return -EINVAL;
}
- 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;
+ if (is_string_field(field)) {
+ filter_build_regex(pred);
+
+ 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;
+ } else {
+ 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;
}
}
- return new_pred;
+ if (pred->op == OP_NE)
+ pred->not = 1;
+
+add_pred_fn:
+ if (!dry_run)
+ return filter_add_pred_fn(ps, call, filter, pred, fn);
+ return 0;
}
-int filter_add_subsystem_pred(struct event_subsystem *system,
- struct filter_pred *pred)
+static void parse_init(struct filter_parse_state *ps,
+ struct filter_op *ops,
+ char *infix_string)
{
- struct ftrace_event_call *call = __start_ftrace_events;
- struct filter_pred *event_pred;
- int i;
+ memset(ps, '\0', sizeof(*ps));
- if (system->preds && !pred->compound)
- filter_free_subsystem_preds(system);
+ ps->infix.string = infix_string;
+ ps->infix.cnt = strlen(infix_string);
+ ps->ops = ops;
- if (!system->preds) {
- system->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred),
- GFP_KERNEL);
- if (!system->preds)
- return -ENOMEM;
+ INIT_LIST_HEAD(&ps->opstack);
+ INIT_LIST_HEAD(&ps->postfix);
+}
+
+static char infix_next(struct filter_parse_state *ps)
+{
+ ps->infix.cnt--;
+
+ return ps->infix.string[ps->infix.tail++];
+}
+
+static char infix_peek(struct filter_parse_state *ps)
+{
+ if (ps->infix.tail == strlen(ps->infix.string))
+ return 0;
+
+ return ps->infix.string[ps->infix.tail];
+}
+
+static void infix_advance(struct filter_parse_state *ps)
+{
+ ps->infix.cnt--;
+ ps->infix.tail++;
+}
+
+static inline int is_precedence_lower(struct filter_parse_state *ps,
+ int a, int b)
+{
+ return ps->ops[a].precedence < ps->ops[b].precedence;
+}
+
+static inline int is_op_char(struct filter_parse_state *ps, char c)
+{
+ int i;
+
+ for (i = 0; strcmp(ps->ops[i].string, "OP_NONE"); i++) {
+ if (ps->ops[i].string[0] == c)
+ return 1;
}
- for (i = 0; i < MAX_FILTER_PRED; i++) {
- if (!system->preds[i]) {
- system->preds[i] = pred;
- break;
+ return 0;
+}
+
+static int infix_get_op(struct filter_parse_state *ps, char firstc)
+{
+ char nextc = infix_peek(ps);
+ char opstr[3];
+ int i;
+
+ opstr[0] = firstc;
+ opstr[1] = nextc;
+ opstr[2] = '\0';
+
+ for (i = 0; strcmp(ps->ops[i].string, "OP_NONE"); i++) {
+ if (!strcmp(opstr, ps->ops[i].string)) {
+ infix_advance(ps);
+ return ps->ops[i].id;
}
}
- if (i == MAX_FILTER_PRED)
+ opstr[1] = '\0';
+
+ for (i = 0; strcmp(ps->ops[i].string, "OP_NONE"); i++) {
+ if (!strcmp(opstr, ps->ops[i].string))
+ return ps->ops[i].id;
+ }
+
+ return OP_NONE;
+}
+
+static inline void clear_operand_string(struct filter_parse_state *ps)
+{
+ memset(ps->operand.string, '\0', MAX_FILTER_STR_VAL);
+ ps->operand.tail = 0;
+}
+
+static inline int append_operand_char(struct filter_parse_state *ps, char c)
+{
+ if (ps->operand.tail == MAX_FILTER_STR_VAL - 1)
return -EINVAL;
- events_for_each(call) {
- int err;
+ ps->operand.string[ps->operand.tail++] = c;
- if (!call->name || !call->regfunc)
- continue;
+ return 0;
+}
- if (strcmp(call->system, system->name))
- continue;
+static int filter_opstack_push(struct filter_parse_state *ps, int op)
+{
+ struct opstack_op *opstack_op;
- if (!find_event_field(call, pred->field_name))
- continue;
+ opstack_op = kmalloc(sizeof(*opstack_op), GFP_KERNEL);
+ if (!opstack_op)
+ return -ENOMEM;
- event_pred = copy_pred(pred);
- if (!event_pred)
- goto oom;
+ opstack_op->op = op;
+ list_add(&opstack_op->list, &ps->opstack);
- err = filter_add_pred(call, event_pred);
- if (err)
- filter_free_pred(event_pred);
- if (err == -ENOMEM)
- goto oom;
+ return 0;
+}
+
+static int filter_opstack_empty(struct filter_parse_state *ps)
+{
+ return list_empty(&ps->opstack);
+}
+
+static int filter_opstack_top(struct filter_parse_state *ps)
+{
+ struct opstack_op *opstack_op;
+
+ if (filter_opstack_empty(ps))
+ return OP_NONE;
+
+ opstack_op = list_first_entry(&ps->opstack, struct opstack_op, list);
+
+ return opstack_op->op;
+}
+
+static int filter_opstack_pop(struct filter_parse_state *ps)
+{
+ struct opstack_op *opstack_op;
+ int op;
+
+ if (filter_opstack_empty(ps))
+ return OP_NONE;
+
+ opstack_op = list_first_entry(&ps->opstack, struct opstack_op, list);
+ op = opstack_op->op;
+ list_del(&opstack_op->list);
+
+ kfree(opstack_op);
+
+ return op;
+}
+
+static void filter_opstack_clear(struct filter_parse_state *ps)
+{
+ while (!filter_opstack_empty(ps))
+ filter_opstack_pop(ps);
+}
+
+static char *curr_operand(struct filter_parse_state *ps)
+{
+ return ps->operand.string;
+}
+
+static int postfix_append_operand(struct filter_parse_state *ps, char *operand)
+{
+ struct postfix_elt *elt;
+
+ elt = kmalloc(sizeof(*elt), GFP_KERNEL);
+ if (!elt)
+ return -ENOMEM;
+
+ elt->op = OP_NONE;
+ elt->operand = kstrdup(operand, GFP_KERNEL);
+ if (!elt->operand) {
+ kfree(elt);
+ return -ENOMEM;
}
+ list_add_tail(&elt->list, &ps->postfix);
+
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;
+static int postfix_append_op(struct filter_parse_state *ps, int op)
+{
+ struct postfix_elt *elt;
+
+ elt = kmalloc(sizeof(*elt), GFP_KERNEL);
+ if (!elt)
+ return -ENOMEM;
+
+ elt->op = op;
+ elt->operand = NULL;
+
+ list_add_tail(&elt->list, &ps->postfix);
+
+ return 0;
+}
+
+static void postfix_clear(struct filter_parse_state *ps)
+{
+ struct postfix_elt *elt;
+
+ while (!list_empty(&ps->postfix)) {
+ elt = list_first_entry(&ps->postfix, struct postfix_elt, list);
+ list_del(&elt->list);
+ kfree(elt->operand);
+ kfree(elt);
+ }
+}
+
+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 (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;
+
+ if (in_string)
+ goto parse_operand;
+
+ if (isspace(ch))
+ continue;
+
+ if (is_op_char(ps, ch)) {
+ op = infix_get_op(ps, ch);
+ if (op == OP_NONE) {
+ parse_error(ps, FILT_ERR_INVALID_OP, 0);
return -EINVAL;
}
- tok_n = 2;
+
+ if (strlen(curr_operand(ps))) {
+ postfix_append_operand(ps, curr_operand(ps));
+ clear_operand_string(ps);
+ }
+
+ while (!filter_opstack_empty(ps)) {
+ top_op = filter_opstack_top(ps);
+ if (!is_precedence_lower(ps, top_op, op)) {
+ top_op = filter_opstack_pop(ps);
+ postfix_append_op(ps, top_op);
+ continue;
+ }
+ break;
+ }
+
+ filter_opstack_push(ps, op);
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 */
+
+ if (ch == '(') {
+ filter_opstack_push(ps, OP_OPEN_PAREN);
+ continue;
+ }
+
+ if (ch == ')') {
+ if (strlen(curr_operand(ps))) {
+ postfix_append_operand(ps, curr_operand(ps));
+ clear_operand_string(ps);
+ }
+
+ top_op = filter_opstack_pop(ps);
+ while (top_op != OP_NONE) {
+ if (top_op == OP_OPEN_PAREN)
+ break;
+ postfix_append_op(ps, top_op);
+ top_op = filter_opstack_pop(ps);
+ }
+ if (top_op == OP_NONE) {
+ parse_error(ps, FILT_ERR_UNBALANCED_PAREN, 0);
+ return -EINVAL;
}
- tok_n = 3;
continue;
}
- if (tok_n == 3) {
- val_str = tok;
- break; /* done */
+parse_operand:
+ if (append_operand_char(ps, ch)) {
+ parse_error(ps, FILT_ERR_OPERAND_TOO_LONG, 0);
+ return -EINVAL;
+ }
+ }
+
+ if (strlen(curr_operand(ps)))
+ postfix_append_operand(ps, curr_operand(ps));
+
+ while (!filter_opstack_empty(ps)) {
+ top_op = filter_opstack_pop(ps);
+ if (top_op == OP_NONE)
+ break;
+ if (top_op == OP_OPEN_PAREN) {
+ parse_error(ps, FILT_ERR_UNBALANCED_PAREN, 0);
+ return -EINVAL;
}
+ postfix_append_op(ps, top_op);
}
- if (!val_str) {
- pred->field_name = NULL;
+ return 0;
+}
+
+static struct filter_pred *create_pred(int op, char *operand1, char *operand2)
+{
+ struct filter_pred *pred;
+
+ pred = kzalloc(sizeof(*pred), GFP_KERNEL);
+ if (!pred)
+ return NULL;
+
+ pred->field_name = kstrdup(operand1, GFP_KERNEL);
+ if (!pred->field_name) {
+ kfree(pred);
+ return NULL;
+ }
+
+ strcpy(pred->regex.pattern, operand2);
+ pred->regex.len = strlen(pred->regex.pattern);
+
+ pred->op = op;
+
+ return pred;
+}
+
+static struct filter_pred *create_logical_pred(int op)
+{
+ struct filter_pred *pred;
+
+ pred = kzalloc(sizeof(*pred), GFP_KERNEL);
+ if (!pred)
+ return NULL;
+
+ pred->op = op;
+
+ return pred;
+}
+
+static int check_preds(struct filter_parse_state *ps)
+{
+ int n_normal_preds = 0, n_logical_preds = 0;
+ struct postfix_elt *elt;
+
+ list_for_each_entry(elt, &ps->postfix, list) {
+ if (elt->op == OP_NONE)
+ continue;
+
+ if (elt->op == OP_AND || elt->op == OP_OR) {
+ n_logical_preds++;
+ continue;
+ }
+ n_normal_preds++;
+ }
+
+ if (!n_normal_preds || n_logical_preds >= n_normal_preds) {
+ parse_error(ps, FILT_ERR_INVALID_FILTER, 0);
return -EINVAL;
}
- pred->field_name = kstrdup(pred->field_name, GFP_KERNEL);
- if (!pred->field_name)
- return -ENOMEM;
+ return 0;
+}
- pred->val = simple_strtoull(val_str, &tmp, 10);
- if (tmp == val_str) {
- pred->str_val = kstrdup(val_str, GFP_KERNEL);
- if (!pred->str_val)
+static int replace_preds(struct ftrace_event_call *call,
+ struct event_filter *filter,
+ struct filter_parse_state *ps,
+ 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)
+ return err;
+
+ list_for_each_entry(elt, &ps->postfix, list) {
+ if (elt->op == OP_NONE) {
+ if (!operand1)
+ operand1 = elt->operand;
+ else if (!operand2)
+ operand2 = elt->operand;
+ else {
+ parse_error(ps, FILT_ERR_TOO_MANY_OPERANDS, 0);
+ return -EINVAL;
+ }
+ 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);
+ goto add_pred;
+ }
+
+ if (!operand1 || !operand2) {
+ parse_error(ps, FILT_ERR_MISSING_FIELD, 0);
+ return -EINVAL;
+ }
+
+ pred = create_pred(elt->op, operand1, operand2);
+add_pred:
+ if (!pred)
return -ENOMEM;
+ err = filter_add_pred(ps, call, filter, pred, dry_run);
+ filter_free_pred(pred);
+ if (err)
+ return err;
+
+ operand1 = operand2 = NULL;
+ }
+
+ return 0;
+}
+
+static int replace_system_preds(struct event_subsystem *system,
+ struct filter_parse_state *ps,
+ char *filter_string)
+{
+ struct ftrace_event_call *call;
+ bool fail = true;
+ int err;
+
+ list_for_each_entry(call, &ftrace_events, list) {
+ struct event_filter *filter = call->filter;
+
+ 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, filter, ps, filter_string, true);
+ if (err)
+ continue;
+
+ /* really apply the filter */
+ filter_disable_preds(call);
+ err = replace_preds(call, filter, ps, filter_string, false);
+ if (err)
+ filter_disable_preds(call);
+ else {
+ call->filter_active = 1;
+ replace_filter_string(filter, filter_string);
+ }
+ fail = false;
}
+ if (fail) {
+ parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0);
+ return -EINVAL;
+ }
return 0;
}
+int apply_event_filter(struct ftrace_event_call *call, char *filter_string)
+{
+ int err;
+ struct filter_parse_state *ps;
+
+ 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);
+ goto out_unlock;
+ }
+
+ err = -ENOMEM;
+ ps = kzalloc(sizeof(*ps), GFP_KERNEL);
+ if (!ps)
+ goto out_unlock;
+
+ filter_disable_preds(call);
+ replace_filter_string(call->filter, filter_string);
+
+ parse_init(ps, filter_ops, filter_string);
+ err = filter_parse(ps);
+ if (err) {
+ append_filter_err(ps, call->filter);
+ goto out;
+ }
+
+ err = replace_preds(call, call->filter, ps, filter_string, false);
+ if (err)
+ append_filter_err(ps, call->filter);
+ else
+ call->filter_active = 1;
+out:
+ filter_opstack_clear(ps);
+ postfix_clear(ps);
+ kfree(ps);
+out_unlock:
+ mutex_unlock(&event_mutex);
+
+ return err;
+}
+
+int apply_subsystem_event_filter(struct event_subsystem *system,
+ char *filter_string)
+{
+ int err;
+ struct filter_parse_state *ps;
+
+ 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);
+ remove_filter_string(system->filter);
+ goto out_unlock;
+ }
+
+ err = -ENOMEM;
+ ps = kzalloc(sizeof(*ps), GFP_KERNEL);
+ if (!ps)
+ goto out_unlock;
+
+ replace_filter_string(system->filter, filter_string);
+
+ parse_init(ps, filter_ops, filter_string);
+ err = filter_parse(ps);
+ if (err) {
+ append_filter_err(ps, system->filter);
+ goto out;
+ }
+
+ err = replace_system_preds(system, ps, filter_string);
+ if (err)
+ append_filter_err(ps, system->filter);
+
+out:
+ filter_opstack_clear(ps);
+ postfix_clear(ps);
+ kfree(ps);
+out_unlock:
+ mutex_unlock(&event_mutex);
+
+ return err;
+}
+
+#ifdef CONFIG_EVENT_PROFILE
+
+void ftrace_profile_free_filter(struct perf_event *event)
+{
+ struct event_filter *filter = event->filter;
+
+ event->filter = NULL;
+ __free_preds(filter);
+}
+
+int ftrace_profile_set_filter(struct perf_event *event, int event_id,
+ char *filter_str)
+{
+ int err;
+ struct event_filter *filter;
+ struct filter_parse_state *ps;
+ struct ftrace_event_call *call = NULL;
+
+ mutex_lock(&event_mutex);
+
+ list_for_each_entry(call, &ftrace_events, list) {
+ if (call->id == event_id)
+ break;
+ }
+
+ err = -EINVAL;
+ if (!call)
+ goto out_unlock;
+
+ err = -EEXIST;
+ if (event->filter)
+ goto out_unlock;
+
+ filter = __alloc_preds();
+ if (IS_ERR(filter)) {
+ err = PTR_ERR(filter);
+ goto out_unlock;
+ }
+
+ err = -ENOMEM;
+ ps = kzalloc(sizeof(*ps), GFP_KERNEL);
+ if (!ps)
+ goto free_preds;
+
+ 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)
+ event->filter = filter;
+
+free_ps:
+ filter_opstack_clear(ps);
+ postfix_clear(ps);
+ kfree(ps);
+
+free_preds:
+ if (err)
+ __free_preds(filter);
+
+out_unlock:
+ mutex_unlock(&event_mutex);
+
+ return err;
+}
+
+#endif /* CONFIG_EVENT_PROFILE */
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff