#include <linux/uaccess.h>
#include <linux/module.h>
#include <linux/ctype.h>
#include <linux/mutex.h>
#include <linux/perf_event.h>
#include <linux/slab.h>
#include "trace.h"
#include "trace_output.h"
#define DEFAULT_SYS_FILTER_MESSAGE \
"### global filter ###\n" \
"# Use this to set filters for multiple events.\n" \
"# Only events with the given fields will be affected.\n" \
"# If no events are modified, an error message will be displayed here"
#define OPS \
C( OP_GLOB, "~" ), \
C( OP_NE, "!=" ), \
C( OP_EQ, "==" ), \
C( OP_LE, "<=" ), \
C( OP_LT, "<" ), \
C( OP_GE, ">=" ), \
C( OP_GT, ">" ), \
C( OP_BAND, "&" ), \
C( OP_MAX, NULL )
#undef C
#define C(a, b) a
enum filter_op_ids { OPS };
#undef C
#define C(a, b) b
static const char * ops[] = { OPS };
enum filter_pred_fn {
FILTER_PRED_FN_NOP,
FILTER_PRED_FN_64,
FILTER_PRED_FN_64_CPUMASK,
FILTER_PRED_FN_S64,
FILTER_PRED_FN_U64,
FILTER_PRED_FN_32,
FILTER_PRED_FN_32_CPUMASK,
FILTER_PRED_FN_S32,
FILTER_PRED_FN_U32,
FILTER_PRED_FN_16,
FILTER_PRED_FN_16_CPUMASK,
FILTER_PRED_FN_S16,
FILTER_PRED_FN_U16,
FILTER_PRED_FN_8,
FILTER_PRED_FN_8_CPUMASK,
FILTER_PRED_FN_S8,
FILTER_PRED_FN_U8,
FILTER_PRED_FN_COMM,
FILTER_PRED_FN_STRING,
FILTER_PRED_FN_STRLOC,
FILTER_PRED_FN_STRRELLOC,
FILTER_PRED_FN_PCHAR_USER,
FILTER_PRED_FN_PCHAR,
FILTER_PRED_FN_CPU,
FILTER_PRED_FN_CPU_CPUMASK,
FILTER_PRED_FN_CPUMASK,
FILTER_PRED_FN_CPUMASK_CPU,
FILTER_PRED_FN_FUNCTION,
FILTER_PRED_FN_,
FILTER_PRED_TEST_VISITED,
};
struct filter_pred {
struct regex *regex;
struct cpumask *mask;
unsigned short *ops;
struct ftrace_event_field *field;
u64 val;
u64 val2;
enum filter_pred_fn fn_num;
int offset;
int not;
int op;
};
#define PRED_FUNC_START OP_LE
#define PRED_FUNC_MAX (OP_BAND - PRED_FUNC_START)
#define ERRORS \
C(NONE, "No error"), \
C(INVALID_OP, "Invalid operator"), \
C(TOO_MANY_OPEN, "Too many '('"), \
C(TOO_MANY_CLOSE, "Too few '('"), \
C(MISSING_QUOTE, "Missing matching quote"), \
C(MISSING_BRACE_OPEN, "Missing '{'"), \
C(MISSING_BRACE_CLOSE, "Missing '}'"), \
C(OPERAND_TOO_LONG, "Operand too long"), \
C(EXPECT_STRING, "Expecting string field"), \
C(EXPECT_DIGIT, "Expecting numeric field"), \
C(ILLEGAL_FIELD_OP, "Illegal operation for field type"), \
C(FIELD_NOT_FOUND, "Field not found"), \
C(ILLEGAL_INTVAL, "Illegal integer value"), \
C(BAD_SUBSYS_FILTER, "Couldn't find or set field in one of a subsystem's events"), \
C(TOO_MANY_PREDS, "Too many terms in predicate expression"), \
C(INVALID_FILTER, "Meaningless filter expression"), \
C(INVALID_CPULIST, "Invalid cpulist"), \
C(IP_FIELD_ONLY, "Only 'ip' field is supported for function trace"), \
C(INVALID_VALUE, "Invalid value (did you forget quotes)?"), \
C(NO_FUNCTION, "Function not found"), \
C(ERRNO, "Error"), \
C(NO_FILTER, "No filter found")
#undef C
#define C(a, b) FILT_ERR_##a
enum { ERRORS };
#undef C
#define C(a, b) b
static const char *err_text[] = { ERRORS };
static bool is_not(const char *str)
{
switch (str[1]) {
case '=':
case '~':
return false;
}
return true;
}
struct prog_entry {
int target;
int when_to_branch;
struct filter_pred *pred;
};
static void update_preds(struct prog_entry *prog, int N, int invert)
{
int t, s;
t = prog[N].target;
s = prog[t].target;
prog[t].when_to_branch = invert;
prog[t].target = N;
prog[N].target = s;
}
struct filter_parse_error {
int lasterr;
int lasterr_pos;
};
static void parse_error(struct filter_parse_error *pe, int err, int pos)
{
pe->lasterr = err;
pe->lasterr_pos = pos;
}
typedef int (*parse_pred_fn)(const char *str, void *data, int pos,
struct filter_parse_error *pe,
struct filter_pred **pred);
enum {
INVERT = 1,
PROCESS_AND = 2,
PROCESS_OR = 4,
};
static void free_predicate(struct filter_pred *pred)
{
if (pred) {
kfree(pred->regex);
kfree(pred->mask);
kfree(pred);
}
}
static struct prog_entry *
predicate_parse(const char *str, int nr_parens, int nr_preds,
parse_pred_fn parse_pred, void *data,
struct filter_parse_error *pe)
{
struct prog_entry *prog_stack;
struct prog_entry *prog;
const char *ptr = str;
char *inverts = NULL;
int *op_stack;
int *top;
int invert = 0;
int ret = -ENOMEM;
int len;
int N = 0;
int i;
nr_preds += 2;
op_stack = kmalloc_objs(*op_stack, nr_parens);
if (!op_stack)
return ERR_PTR(-ENOMEM);
prog_stack = kzalloc_objs(*prog_stack, nr_preds);
if (!prog_stack) {
parse_error(pe, -ENOMEM, 0);
goto out_free;
}
inverts = kmalloc_array(nr_preds, sizeof(*inverts), GFP_KERNEL);
if (!inverts) {
parse_error(pe, -ENOMEM, 0);
goto out_free;
}
top = op_stack;
prog = prog_stack;
*top = 0;
while (*ptr) {
const char *next = ptr++;
if (isspace(*next))
continue;
switch (*next) {
case '(':
if (top - op_stack > nr_parens) {
ret = -EINVAL;
goto out_free;
}
*(++top) = invert;
continue;
case '!':
if (!is_not(next))
break;
invert = !invert;
continue;
}
if (N >= nr_preds) {
parse_error(pe, FILT_ERR_TOO_MANY_PREDS, next - str);
goto out_free;
}
inverts[N] = invert;
prog[N].target = N-1;
len = parse_pred(next, data, ptr - str, pe, &prog[N].pred);
if (len < 0) {
ret = len;
goto out_free;
}
ptr = next + len;
N++;
ret = -1;
while (1) {
next = ptr++;
if (isspace(*next))
continue;
switch (*next) {
case ')':
case '\0':
break;
case '&':
case '|':
if (next[1] == next[0]) {
ptr++;
break;
}
fallthrough;
default:
parse_error(pe, FILT_ERR_TOO_MANY_PREDS,
next - str);
goto out_free;
}
invert = *top & INVERT;
if (*top & PROCESS_AND) {
update_preds(prog, N - 1, invert);
*top &= ~PROCESS_AND;
}
if (*next == '&') {
*top |= PROCESS_AND;
break;
}
if (*top & PROCESS_OR) {
update_preds(prog, N - 1, !invert);
*top &= ~PROCESS_OR;
}
if (*next == '|') {
*top |= PROCESS_OR;
break;
}
if (!*next)
goto out;
if (top == op_stack) {
ret = -1;
parse_error(pe, FILT_ERR_TOO_MANY_CLOSE, ptr - str);
goto out_free;
}
top--;
}
}
out:
if (top != op_stack) {
parse_error(pe, FILT_ERR_TOO_MANY_OPEN, ptr - str);
goto out_free;
}
if (!N) {
ret = -EINVAL;
parse_error(pe, FILT_ERR_NO_FILTER, ptr - str);
goto out_free;
}
prog[N].pred = NULL;
prog[N].target = 1;
prog[N+1].pred = NULL;
prog[N+1].target = 0;
prog[N-1].target = N;
prog[N-1].when_to_branch = false;
for (i = N-1 ; i--; ) {
int target = prog[i].target;
if (prog[i].when_to_branch == prog[target].when_to_branch)
prog[i].target = prog[target].target;
}
for (i = 0; i < N; i++) {
invert = inverts[i] ^ prog[i].when_to_branch;
prog[i].when_to_branch = invert;
if (WARN_ON(prog[i].target <= i)) {
ret = -EINVAL;
goto out_free;
}
}
kfree(op_stack);
kfree(inverts);
return prog;
out_free:
kfree(op_stack);
kfree(inverts);
if (prog_stack) {
for (i = 0; prog_stack[i].pred; i++)
free_predicate(prog_stack[i].pred);
kfree(prog_stack);
}
return ERR_PTR(ret);
}
static inline int
do_filter_cpumask(int op, const struct cpumask *mask, const struct cpumask *cmp)
{
switch (op) {
case OP_EQ:
return cpumask_equal(mask, cmp);
case OP_NE:
return !cpumask_equal(mask, cmp);
case OP_BAND:
return cpumask_intersects(mask, cmp);
default:
return 0;
}
}
static inline int
do_filter_scalar_cpumask(int op, unsigned int cpu, const struct cpumask *mask)
{
switch (op) {
case OP_EQ:
return false;
case OP_NE:
return true;
case OP_BAND:
return cpumask_test_cpu(cpu, mask);
default:
return 0;
}
}
static inline int
do_filter_cpumask_scalar(int op, const struct cpumask *mask, unsigned int cpu)
{
switch (op) {
case OP_EQ:
return cpumask_test_cpu(cpu, mask) &&
cpumask_nth(1, mask) >= nr_cpu_ids;
case OP_NE:
return !cpumask_test_cpu(cpu, mask) ||
cpumask_nth(1, mask) < nr_cpu_ids;
case OP_BAND:
return cpumask_test_cpu(cpu, mask);
default:
return 0;
}
}
enum pred_cmp_types {
PRED_CMP_TYPE_NOP,
PRED_CMP_TYPE_LT,
PRED_CMP_TYPE_LE,
PRED_CMP_TYPE_GT,
PRED_CMP_TYPE_GE,
PRED_CMP_TYPE_BAND,
};
#define DEFINE_COMPARISON_PRED(type) \
static int filter_pred_##type(struct filter_pred *pred, void *event) \
{ \
switch (pred->op) { \
case OP_LT: { \
type *addr = (type *)(event + pred->offset); \
type val = (type)pred->val; \
return *addr < val; \
} \
case OP_LE: { \
type *addr = (type *)(event + pred->offset); \
type val = (type)pred->val; \
return *addr <= val; \
} \
case OP_GT: { \
type *addr = (type *)(event + pred->offset); \
type val = (type)pred->val; \
return *addr > val; \
} \
case OP_GE: { \
type *addr = (type *)(event + pred->offset); \
type val = (type)pred->val; \
return *addr >= val; \
} \
case OP_BAND: { \
type *addr = (type *)(event + pred->offset); \
type val = (type)pred->val; \
return !!(*addr & val); \
} \
default: \
return 0; \
} \
}
#define DEFINE_CPUMASK_COMPARISON_PRED(size) \
static int filter_pred_##size##_cpumask(struct filter_pred *pred, void *event) \
{ \
u##size *addr = (u##size *)(event + pred->offset); \
unsigned int cpu = *addr; \
\
if (cpu >= nr_cpu_ids) \
return 0; \
\
return do_filter_scalar_cpumask(pred->op, cpu, pred->mask); \
}
#define DEFINE_EQUALITY_PRED(size) \
static int filter_pred_##size(struct filter_pred *pred, void *event) \
{ \
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);
DEFINE_COMPARISON_PRED(u32);
DEFINE_COMPARISON_PRED(s16);
DEFINE_COMPARISON_PRED(u16);
DEFINE_COMPARISON_PRED(s8);
DEFINE_COMPARISON_PRED(u8);
DEFINE_CPUMASK_COMPARISON_PRED(64);
DEFINE_CPUMASK_COMPARISON_PRED(32);
DEFINE_CPUMASK_COMPARISON_PRED(16);
DEFINE_CPUMASK_COMPARISON_PRED(8);
DEFINE_EQUALITY_PRED(64);
DEFINE_EQUALITY_PRED(32);
DEFINE_EQUALITY_PRED(16);
DEFINE_EQUALITY_PRED(8);
#define USTRING_BUF_SIZE 1024
struct ustring_buffer {
char buffer[USTRING_BUF_SIZE];
};
static __percpu struct ustring_buffer *ustring_per_cpu;
static __always_inline char *test_string(char *str)
{
struct ustring_buffer *ubuf;
char *kstr;
if (!ustring_per_cpu)
return NULL;
ubuf = this_cpu_ptr(ustring_per_cpu);
kstr = ubuf->buffer;
if (strncpy_from_kernel_nofault(kstr, str, USTRING_BUF_SIZE) < 0)
return NULL;
return kstr;
}
static __always_inline char *test_ustring(char *str)
{
struct ustring_buffer *ubuf;
char __user *ustr;
char *kstr;
if (!ustring_per_cpu)
return NULL;
ubuf = this_cpu_ptr(ustring_per_cpu);
kstr = ubuf->buffer;
ustr = (char __user *)str;
if (strncpy_from_user_nofault(kstr, ustr, USTRING_BUF_SIZE) < 0)
return NULL;
return kstr;
}
static int filter_pred_string(struct filter_pred *pred, void *event)
{
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 __always_inline int filter_pchar(struct filter_pred *pred, char *str)
{
int cmp, match;
int len;
len = strlen(str) + 1;
cmp = pred->regex->match(str, pred->regex, len);
match = cmp ^ pred->not;
return match;
}
static int filter_pred_pchar(struct filter_pred *pred, void *event)
{
char **addr = (char **)(event + pred->offset);
char *str;
str = test_string(*addr);
if (!str)
return 0;
return filter_pchar(pred, str);
}
static int filter_pred_pchar_user(struct filter_pred *pred, void *event)
{
char **addr = (char **)(event + pred->offset);
char *str;
str = test_ustring(*addr);
if (!str)
return 0;
return filter_pchar(pred, str);
}
static int filter_pred_strloc(struct filter_pred *pred, void *event)
{
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;
return match;
}
static int filter_pred_strrelloc(struct filter_pred *pred, void *event)
{
u32 *item = (u32 *)(event + pred->offset);
u32 str_item = *item;
int str_loc = str_item & 0xffff;
int str_len = str_item >> 16;
char *addr = (char *)(&item[1]) + str_loc;
int cmp, match;
cmp = pred->regex->match(addr, pred->regex, str_len);
match = cmp ^ pred->not;
return match;
}
static int filter_pred_cpu(struct filter_pred *pred, void *event)
{
int cpu, cmp;
cpu = raw_smp_processor_id();
cmp = pred->val;
switch (pred->op) {
case OP_EQ:
return cpu == cmp;
case OP_NE:
return cpu != cmp;
case OP_LT:
return cpu < cmp;
case OP_LE:
return cpu <= cmp;
case OP_GT:
return cpu > cmp;
case OP_GE:
return cpu >= cmp;
default:
return 0;
}
}
static int filter_pred_cpu_cpumask(struct filter_pred *pred, void *event)
{
int cpu = raw_smp_processor_id();
return do_filter_scalar_cpumask(pred->op, cpu, pred->mask);
}
static int filter_pred_cpumask(struct filter_pred *pred, void *event)
{
u32 item = *(u32 *)(event + pred->offset);
int loc = item & 0xffff;
const struct cpumask *mask = (event + loc);
const struct cpumask *cmp = pred->mask;
return do_filter_cpumask(pred->op, mask, cmp);
}
static int filter_pred_cpumask_cpu(struct filter_pred *pred, void *event)
{
u32 item = *(u32 *)(event + pred->offset);
int loc = item & 0xffff;
const struct cpumask *mask = (event + loc);
unsigned int cpu = pred->val;
return do_filter_cpumask_scalar(pred->op, mask, cpu);
}
static int filter_pred_comm(struct filter_pred *pred, void *event)
{
int cmp;
cmp = pred->regex->match(current->comm, pred->regex,
TASK_COMM_LEN);
return cmp ^ pred->not;
}
static int filter_pred_function(struct filter_pred *pred, void *event)
{
unsigned long *addr = (unsigned long *)(event + pred->offset);
unsigned long start = (unsigned long)pred->val;
unsigned long end = (unsigned long)pred->val2;
int ret = *addr >= start && *addr < end;
return pred->op == OP_EQ ? ret : !ret;
}
static int regex_match_full(char *str, struct regex *r, int len)
{
if (!len)
return strcmp(str, r->pattern) == 0;
return strncmp(str, r->pattern, len) == 0;
}
static int regex_match_front(char *str, struct regex *r, int len)
{
if (len && len < r->len)
return 0;
return strncmp(str, r->pattern, r->len) == 0;
}
static int regex_match_middle(char *str, struct regex *r, int len)
{
if (!len)
return strstr(str, r->pattern) != NULL;
return strnstr(str, r->pattern, len) != NULL;
}
static int regex_match_end(char *str, struct regex *r, int len)
{
int strlen = len - 1;
if (strlen >= r->len &&
memcmp(str + strlen - r->len, r->pattern, r->len) == 0)
return 1;
return 0;
}
static int regex_match_glob(char *str, struct regex *r, int len __maybe_unused)
{
if (glob_match(r->pattern, str))
return 1;
return 0;
}
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;
if (isdigit(buff[0]))
return MATCH_INDEX;
for (i = 0; i < len; i++) {
if (buff[i] == '*') {
if (!i) {
type = MATCH_END_ONLY;
} else if (i == len - 1) {
if (type == MATCH_END_ONLY)
type = MATCH_MIDDLE_ONLY;
else
type = MATCH_FRONT_ONLY;
buff[i] = 0;
break;
} else {
return MATCH_GLOB;
}
} else if (strchr("[?\\", buff[i])) {
return MATCH_GLOB;
}
}
if (buff[0] == '*')
*search = buff + 1;
return type;
}
static void filter_build_regex(struct filter_pred *pred)
{
struct regex *r = pred->regex;
char *search;
enum regex_type type = MATCH_FULL;
if (pred->op == OP_GLOB) {
type = filter_parse_regex(r->pattern, r->len, &search, &pred->not);
r->len = strlen(search);
memmove(r->pattern, search, r->len+1);
}
switch (type) {
case MATCH_INDEX:
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;
case MATCH_GLOB:
r->match = regex_match_glob;
break;
}
}
#ifdef CONFIG_FTRACE_STARTUP_TEST
static int test_pred_visited_fn(struct filter_pred *pred, void *event);
#else
static int test_pred_visited_fn(struct filter_pred *pred, void *event)
{
return 0;
}
#endif
static int filter_pred_fn_call(struct filter_pred *pred, void *event);
int filter_match_preds(struct event_filter *filter, void *rec)
{
struct prog_entry *prog;
int i;
if (!filter)
return 1;
prog = rcu_dereference_raw(filter->prog);
if (!prog)
return 1;
for (i = 0; prog[i].pred; i++) {
struct filter_pred *pred = prog[i].pred;
int match = filter_pred_fn_call(pred, rec);
if (match == prog[i].when_to_branch)
i = prog[i].target;
}
return prog[i].target;
}
EXPORT_SYMBOL_GPL(filter_match_preds);
static void remove_filter_string(struct event_filter *filter)
{
if (!filter)
return;
kfree(filter->filter_string);
filter->filter_string = NULL;
}
static void append_filter_err(struct trace_array *tr,
struct filter_parse_error *pe,
struct event_filter *filter)
{
struct trace_seq *s;
int pos = pe->lasterr_pos;
char *buf;
int len;
if (WARN_ON(!filter->filter_string))
return;
s = kmalloc_obj(*s);
if (!s)
return;
trace_seq_init(s);
len = strlen(filter->filter_string);
if (pos > len)
pos = len;
if (pos)
pos++;
trace_seq_puts(s, filter->filter_string);
if (pe->lasterr > 0) {
trace_seq_printf(s, "\n%*s", pos, "^");
trace_seq_printf(s, "\nparse_error: %s\n", err_text[pe->lasterr]);
tracing_log_err(tr, "event filter parse error",
filter->filter_string, err_text,
pe->lasterr, pe->lasterr_pos);
} else {
trace_seq_printf(s, "\nError: (%d)\n", pe->lasterr);
tracing_log_err(tr, "event filter parse error",
filter->filter_string, err_text,
FILT_ERR_ERRNO, 0);
}
trace_seq_putc(s, 0);
buf = kmemdup_nul(s->buffer, s->seq.len, GFP_KERNEL);
if (buf) {
kfree(filter->filter_string);
filter->filter_string = buf;
}
kfree(s);
}
static inline struct event_filter *event_filter(struct trace_event_file *file)
{
return rcu_dereference_protected(file->filter,
lockdep_is_held(&event_mutex));
}
void print_event_filter(struct trace_event_file *file, struct trace_seq *s)
{
struct event_filter *filter = event_filter(file);
if (filter && filter->filter_string)
trace_seq_printf(s, "%s\n", filter->filter_string);
else
trace_seq_puts(s, "none\n");
}
void print_subsystem_event_filter(struct event_subsystem *system,
struct trace_seq *s)
{
struct event_filter *filter;
mutex_lock(&event_mutex);
filter = system->filter;
if (filter && filter->filter_string)
trace_seq_printf(s, "%s\n", filter->filter_string);
else
trace_seq_puts(s, DEFAULT_SYS_FILTER_MESSAGE "\n");
mutex_unlock(&event_mutex);
}
static void free_prog(struct event_filter *filter)
{
struct prog_entry *prog;
int i;
prog = rcu_access_pointer(filter->prog);
if (!prog)
return;
for (i = 0; prog[i].pred; i++)
free_predicate(prog[i].pred);
kfree(prog);
}
static void filter_disable(struct trace_event_file *file)
{
unsigned long old_flags = file->flags;
file->flags &= ~EVENT_FILE_FL_FILTERED;
if (old_flags != file->flags)
trace_buffered_event_disable();
}
static void __free_filter(struct event_filter *filter)
{
if (!filter)
return;
free_prog(filter);
kfree(filter->filter_string);
kfree(filter);
}
void free_event_filter(struct event_filter *filter)
{
__free_filter(filter);
}
static inline void __remove_filter(struct trace_event_file *file)
{
filter_disable(file);
remove_filter_string(event_filter(file));
}
static void filter_free_subsystem_preds(struct trace_subsystem_dir *dir,
struct trace_array *tr)
{
struct trace_event_file *file;
list_for_each_entry(file, &tr->events, list) {
if (file->system != dir)
continue;
__remove_filter(file);
}
}
struct filter_list {
struct list_head list;
struct event_filter *filter;
};
struct filter_head {
struct list_head list;
union {
struct rcu_head rcu;
struct rcu_work rwork;
};
};
static void free_filter_list(struct filter_head *filter_list)
{
struct filter_list *filter_item, *tmp;
list_for_each_entry_safe(filter_item, tmp, &filter_list->list, list) {
__free_filter(filter_item->filter);
list_del(&filter_item->list);
kfree(filter_item);
}
kfree(filter_list);
}
static void free_filter_list_work(struct work_struct *work)
{
struct filter_head *filter_list;
filter_list = container_of(to_rcu_work(work), struct filter_head, rwork);
free_filter_list(filter_list);
}
static void free_filter_list_tasks(struct rcu_head *rhp)
{
struct filter_head *filter_list = container_of(rhp, struct filter_head, rcu);
INIT_RCU_WORK(&filter_list->rwork, free_filter_list_work);
queue_rcu_work(system_dfl_wq, &filter_list->rwork);
}
static void delay_free_filter(struct filter_head *head)
{
call_rcu_tasks_trace(&head->rcu, free_filter_list_tasks);
}
static void try_delay_free_filter(struct event_filter *filter)
{
struct filter_head *head;
struct filter_list *item;
head = kmalloc_obj(*head);
if (!head)
goto free_now;
INIT_LIST_HEAD(&head->list);
item = kmalloc_obj(*item);
if (!item) {
kfree(head);
goto free_now;
}
item->filter = filter;
list_add_tail(&item->list, &head->list);
delay_free_filter(head);
return;
free_now:
tracepoint_synchronize_unregister();
__free_filter(filter);
}
static inline void __free_subsystem_filter(struct trace_event_file *file)
{
__free_filter(event_filter(file));
file->filter = NULL;
}
static inline void event_set_filter(struct trace_event_file *file,
struct event_filter *filter)
{
rcu_assign_pointer(file->filter, filter);
}
static inline void event_clear_filter(struct trace_event_file *file)
{
RCU_INIT_POINTER(file->filter, NULL);
}
static void filter_free_subsystem_filters(struct trace_subsystem_dir *dir,
struct trace_array *tr,
struct event_filter *filter)
{
struct trace_event_file *file;
struct filter_head *head;
struct filter_list *item;
head = kmalloc_obj(*head);
if (!head)
goto free_now;
INIT_LIST_HEAD(&head->list);
list_for_each_entry(file, &tr->events, list) {
if (file->system != dir)
continue;
item = kmalloc_obj(*item);
if (!item)
goto free_now;
item->filter = event_filter(file);
list_add_tail(&item->list, &head->list);
event_clear_filter(file);
}
item = kmalloc_obj(*item);
if (!item)
goto free_now;
item->filter = filter;
list_add_tail(&item->list, &head->list);
delay_free_filter(head);
return;
free_now:
tracepoint_synchronize_unregister();
if (head)
free_filter_list(head);
list_for_each_entry(file, &tr->events, list) {
if (file->system != dir || !file->filter)
continue;
__free_subsystem_filter(file);
}
__free_filter(filter);
}
int filter_assign_type(const char *type)
{
if (strstr(type, "__data_loc")) {
if (strstr(type, "char"))
return FILTER_DYN_STRING;
if (strstr(type, "cpumask_t"))
return FILTER_CPUMASK;
}
if (strstr(type, "__rel_loc") && strstr(type, "char"))
return FILTER_RDYN_STRING;
if (strchr(type, '[') && strstr(type, "char"))
return FILTER_STATIC_STRING;
if (strcmp(type, "char *") == 0 || strcmp(type, "const char *") == 0)
return FILTER_PTR_STRING;
return FILTER_OTHER;
}
static enum filter_pred_fn select_comparison_fn(enum filter_op_ids op,
int field_size, int field_is_signed)
{
enum filter_pred_fn fn = FILTER_PRED_FN_NOP;
int pred_func_index = -1;
switch (op) {
case OP_EQ:
case OP_NE:
break;
default:
if (WARN_ON_ONCE(op < PRED_FUNC_START))
return fn;
pred_func_index = op - PRED_FUNC_START;
if (WARN_ON_ONCE(pred_func_index > PRED_FUNC_MAX))
return fn;
}
switch (field_size) {
case 8:
if (pred_func_index < 0)
fn = FILTER_PRED_FN_64;
else if (field_is_signed)
fn = FILTER_PRED_FN_S64;
else
fn = FILTER_PRED_FN_U64;
break;
case 4:
if (pred_func_index < 0)
fn = FILTER_PRED_FN_32;
else if (field_is_signed)
fn = FILTER_PRED_FN_S32;
else
fn = FILTER_PRED_FN_U32;
break;
case 2:
if (pred_func_index < 0)
fn = FILTER_PRED_FN_16;
else if (field_is_signed)
fn = FILTER_PRED_FN_S16;
else
fn = FILTER_PRED_FN_U16;
break;
case 1:
if (pred_func_index < 0)
fn = FILTER_PRED_FN_8;
else if (field_is_signed)
fn = FILTER_PRED_FN_S8;
else
fn = FILTER_PRED_FN_U8;
break;
}
return fn;
}
static int filter_pred_fn_call(struct filter_pred *pred, void *event)
{
switch (pred->fn_num) {
case FILTER_PRED_FN_64:
return filter_pred_64(pred, event);
case FILTER_PRED_FN_64_CPUMASK:
return filter_pred_64_cpumask(pred, event);
case FILTER_PRED_FN_S64:
return filter_pred_s64(pred, event);
case FILTER_PRED_FN_U64:
return filter_pred_u64(pred, event);
case FILTER_PRED_FN_32:
return filter_pred_32(pred, event);
case FILTER_PRED_FN_32_CPUMASK:
return filter_pred_32_cpumask(pred, event);
case FILTER_PRED_FN_S32:
return filter_pred_s32(pred, event);
case FILTER_PRED_FN_U32:
return filter_pred_u32(pred, event);
case FILTER_PRED_FN_16:
return filter_pred_16(pred, event);
case FILTER_PRED_FN_16_CPUMASK:
return filter_pred_16_cpumask(pred, event);
case FILTER_PRED_FN_S16:
return filter_pred_s16(pred, event);
case FILTER_PRED_FN_U16:
return filter_pred_u16(pred, event);
case FILTER_PRED_FN_8:
return filter_pred_8(pred, event);
case FILTER_PRED_FN_8_CPUMASK:
return filter_pred_8_cpumask(pred, event);
case FILTER_PRED_FN_S8:
return filter_pred_s8(pred, event);
case FILTER_PRED_FN_U8:
return filter_pred_u8(pred, event);
case FILTER_PRED_FN_COMM:
return filter_pred_comm(pred, event);
case FILTER_PRED_FN_STRING:
return filter_pred_string(pred, event);
case FILTER_PRED_FN_STRLOC:
return filter_pred_strloc(pred, event);
case FILTER_PRED_FN_STRRELLOC:
return filter_pred_strrelloc(pred, event);
case FILTER_PRED_FN_PCHAR_USER:
return filter_pred_pchar_user(pred, event);
case FILTER_PRED_FN_PCHAR:
return filter_pred_pchar(pred, event);
case FILTER_PRED_FN_CPU:
return filter_pred_cpu(pred, event);
case FILTER_PRED_FN_CPU_CPUMASK:
return filter_pred_cpu_cpumask(pred, event);
case FILTER_PRED_FN_CPUMASK:
return filter_pred_cpumask(pred, event);
case FILTER_PRED_FN_CPUMASK_CPU:
return filter_pred_cpumask_cpu(pred, event);
case FILTER_PRED_FN_FUNCTION:
return filter_pred_function(pred, event);
case FILTER_PRED_TEST_VISITED:
return test_pred_visited_fn(pred, event);
default:
return 0;
}
}
static int parse_pred(const char *str, void *data,
int pos, struct filter_parse_error *pe,
struct filter_pred **pred_ptr)
{
struct trace_event_call *call = data;
struct ftrace_event_field *field;
struct filter_pred *pred = NULL;
unsigned long offset;
unsigned long size;
unsigned long ip;
char num_buf[24];
char *field_name;
char *name;
bool function = false;
bool ustring = false;
char q;
u64 val;
int len;
int ret;
int op;
int s;
int i = 0;
while (isspace(str[i]))
i++;
s = i;
while (isalnum(str[i]) || str[i] == '_')
i++;
len = i - s;
if (!len)
return -1;
field_name = kmemdup_nul(str + s, len, GFP_KERNEL);
if (!field_name)
return -ENOMEM;
field = trace_find_event_field(call, field_name);
kfree(field_name);
if (!field) {
parse_error(pe, FILT_ERR_FIELD_NOT_FOUND, pos + i);
return -EINVAL;
}
if ((len = str_has_prefix(str + i, ".ustring"))) {
ustring = true;
i += len;
}
if ((len = str_has_prefix(str + i, ".function"))) {
function = true;
i += len;
}
while (isspace(str[i]))
i++;
for (op = 0; ops[op]; op++) {
if (strncmp(str + i, ops[op], strlen(ops[op])) == 0)
break;
}
if (!ops[op]) {
parse_error(pe, FILT_ERR_INVALID_OP, pos + i);
goto err_free;
}
i += strlen(ops[op]);
while (isspace(str[i]))
i++;
s = i;
pred = kzalloc_obj(*pred);
if (!pred)
return -ENOMEM;
pred->field = field;
pred->offset = field->offset;
pred->op = op;
if (function) {
if (field->size != sizeof(long)) {
parse_error(pe, FILT_ERR_ILLEGAL_FIELD_OP, pos + i);
goto err_free;
}
switch (op) {
case OP_NE:
case OP_EQ:
break;
default:
parse_error(pe, FILT_ERR_INVALID_OP, pos + i);
goto err_free;
}
if (isdigit(str[i])) {
while (isalnum(str[i]))
i++;
len = i - s;
if (len >= sizeof(num_buf)) {
parse_error(pe, FILT_ERR_OPERAND_TOO_LONG, pos + i);
goto err_free;
}
memcpy(num_buf, str + s, len);
num_buf[len] = 0;
ret = kstrtoul(num_buf, 0, &ip);
if (ret) {
parse_error(pe, FILT_ERR_INVALID_VALUE, pos + i);
goto err_free;
}
} else {
s = i;
for (; str[i] && !isspace(str[i]); i++)
;
len = i - s;
name = kmemdup_nul(str + s, len, GFP_KERNEL);
if (!name)
goto err_mem;
ip = kallsyms_lookup_name(name);
kfree(name);
if (!ip) {
parse_error(pe, FILT_ERR_NO_FUNCTION, pos + i);
goto err_free;
}
}
if (!kallsyms_lookup_size_offset(ip, &size, &offset)) {
parse_error(pe, FILT_ERR_NO_FUNCTION, pos + i);
goto err_free;
}
pred->fn_num = FILTER_PRED_FN_FUNCTION;
pred->val = ip - offset;
pred->val2 = pred->val + size;
} else if (ftrace_event_is_function(call)) {
if (strcmp(field->name, "ip") != 0) {
parse_error(pe, FILT_ERR_IP_FIELD_ONLY, pos + i);
goto err_free;
}
pred->fn_num = FILTER_PRED_FN_NOP;
if (str[i] == '\'' || str[i] == '"')
q = str[i];
else
q = 0;
for (i++; str[i]; i++) {
if (q && str[i] == q)
break;
if (!q && (str[i] == ')' || str[i] == '&' ||
str[i] == '|'))
break;
}
if (q)
s++;
len = i - s;
if (len >= MAX_FILTER_STR_VAL) {
parse_error(pe, FILT_ERR_OPERAND_TOO_LONG, pos + i);
goto err_free;
}
pred->regex = kzalloc_obj(*pred->regex);
if (!pred->regex)
goto err_mem;
pred->regex->len = len;
memcpy(pred->regex->pattern, str + s, len);
pred->regex->pattern[len] = 0;
} else if (!strncmp(str + i, "CPUS", 4)) {
unsigned int maskstart;
bool single;
char *tmp;
switch (field->filter_type) {
case FILTER_CPUMASK:
case FILTER_CPU:
case FILTER_OTHER:
break;
default:
parse_error(pe, FILT_ERR_ILLEGAL_FIELD_OP, pos + i);
goto err_free;
}
switch (op) {
case OP_EQ:
case OP_NE:
case OP_BAND:
break;
default:
parse_error(pe, FILT_ERR_ILLEGAL_FIELD_OP, pos + i);
goto err_free;
}
i += 4;
if (str[i++] != '{') {
parse_error(pe, FILT_ERR_MISSING_BRACE_OPEN, pos + i);
goto err_free;
}
maskstart = i;
for (; str[i] && str[i] != '}'; i++)
;
if (str[i] != '}') {
parse_error(pe, FILT_ERR_MISSING_BRACE_CLOSE, pos + i);
goto err_free;
}
if (maskstart == i) {
parse_error(pe, FILT_ERR_INVALID_CPULIST, pos + i);
goto err_free;
}
tmp = kmalloc((i - maskstart) + 1, GFP_KERNEL);
if (!tmp)
goto err_mem;
strscpy(tmp, str + maskstart, (i - maskstart) + 1);
pred->mask = kzalloc(cpumask_size(), GFP_KERNEL);
if (!pred->mask) {
kfree(tmp);
goto err_mem;
}
if (cpulist_parse(tmp, pred->mask)) {
kfree(tmp);
parse_error(pe, FILT_ERR_INVALID_CPULIST, pos + i);
goto err_free;
}
kfree(tmp);
i++;
single = cpumask_weight(pred->mask) == 1;
if (single) {
pred->val = cpumask_first(pred->mask);
kfree(pred->mask);
pred->mask = NULL;
}
if (field->filter_type == FILTER_CPUMASK) {
pred->fn_num = single ?
FILTER_PRED_FN_CPUMASK_CPU :
FILTER_PRED_FN_CPUMASK;
} else if (field->filter_type == FILTER_CPU) {
if (single) {
if (pred->op == OP_BAND)
pred->op = OP_EQ;
pred->fn_num = FILTER_PRED_FN_CPU;
} else {
pred->fn_num = FILTER_PRED_FN_CPU_CPUMASK;
}
} else if (single) {
if (pred->op == OP_BAND)
pred->op = OP_EQ;
pred->fn_num = select_comparison_fn(pred->op, field->size, false);
if (pred->op == OP_NE)
pred->not = 1;
} else {
switch (field->size) {
case 8:
pred->fn_num = FILTER_PRED_FN_64_CPUMASK;
break;
case 4:
pred->fn_num = FILTER_PRED_FN_32_CPUMASK;
break;
case 2:
pred->fn_num = FILTER_PRED_FN_16_CPUMASK;
break;
case 1:
pred->fn_num = FILTER_PRED_FN_8_CPUMASK;
break;
}
}
} else if (str[i] == '\'' || str[i] == '"') {
char q = str[i];
switch (op) {
case OP_NE:
pred->not = 1;
fallthrough;
case OP_GLOB:
case OP_EQ:
break;
default:
parse_error(pe, FILT_ERR_ILLEGAL_FIELD_OP, pos + i);
goto err_free;
}
if (!is_string_field(field)) {
parse_error(pe, FILT_ERR_EXPECT_DIGIT, pos + i);
goto err_free;
}
for (i++; str[i]; i++) {
if (str[i] == q)
break;
}
if (!str[i]) {
parse_error(pe, FILT_ERR_MISSING_QUOTE, pos + i);
goto err_free;
}
s++;
len = i - s;
if (len >= MAX_FILTER_STR_VAL) {
parse_error(pe, FILT_ERR_OPERAND_TOO_LONG, pos + i);
goto err_free;
}
pred->regex = kzalloc_obj(*pred->regex);
if (!pred->regex)
goto err_mem;
pred->regex->len = len;
memcpy(pred->regex->pattern, str + s, len);
pred->regex->pattern[len] = 0;
filter_build_regex(pred);
if (field->filter_type == FILTER_COMM) {
pred->fn_num = FILTER_PRED_FN_COMM;
} else if (field->filter_type == FILTER_STATIC_STRING) {
pred->fn_num = FILTER_PRED_FN_STRING;
pred->regex->field_len = field->size;
} else if (field->filter_type == FILTER_DYN_STRING) {
pred->fn_num = FILTER_PRED_FN_STRLOC;
} else if (field->filter_type == FILTER_RDYN_STRING)
pred->fn_num = FILTER_PRED_FN_STRRELLOC;
else {
if (!ustring_per_cpu) {
ustring_per_cpu = alloc_percpu(struct ustring_buffer);
if (!ustring_per_cpu)
goto err_mem;
}
if (ustring)
pred->fn_num = FILTER_PRED_FN_PCHAR_USER;
else
pred->fn_num = FILTER_PRED_FN_PCHAR;
}
i++;
} else if (isdigit(str[i]) || str[i] == '-') {
if (is_string_field(field)) {
parse_error(pe, FILT_ERR_EXPECT_STRING, pos + i);
goto err_free;
}
if (op == OP_GLOB) {
parse_error(pe, FILT_ERR_ILLEGAL_FIELD_OP, pos + i);
goto err_free;
}
if (str[i] == '-')
i++;
while (isalnum(str[i]))
i++;
len = i - s;
if (len >= sizeof(num_buf)) {
parse_error(pe, FILT_ERR_OPERAND_TOO_LONG, pos + i);
goto err_free;
}
memcpy(num_buf, str + s, len);
num_buf[len] = 0;
if (field->is_signed)
ret = kstrtoll(num_buf, 0, &val);
else
ret = kstrtoull(num_buf, 0, &val);
if (ret) {
parse_error(pe, FILT_ERR_ILLEGAL_INTVAL, pos + s);
goto err_free;
}
pred->val = val;
if (field->filter_type == FILTER_CPU)
pred->fn_num = FILTER_PRED_FN_CPU;
else {
pred->fn_num = select_comparison_fn(pred->op, field->size,
field->is_signed);
if (pred->op == OP_NE)
pred->not = 1;
}
} else {
parse_error(pe, FILT_ERR_INVALID_VALUE, pos + i);
goto err_free;
}
*pred_ptr = pred;
return i;
err_free:
free_predicate(pred);
return -EINVAL;
err_mem:
free_predicate(pred);
return -ENOMEM;
}
enum {
TOO_MANY_CLOSE = -1,
TOO_MANY_OPEN = -2,
MISSING_QUOTE = -3,
};
static int calc_stack(const char *str, int *parens, int *preds, int *err)
{
bool is_pred = false;
int nr_preds = 0;
int open = 1;
int last_quote = 0;
int max_open = 1;
int quote = 0;
int i;
*err = 0;
for (i = 0; str[i]; i++) {
if (isspace(str[i]))
continue;
if (quote) {
if (str[i] == quote)
quote = 0;
continue;
}
switch (str[i]) {
case '\'':
case '"':
quote = str[i];
last_quote = i;
break;
case '|':
case '&':
if (str[i+1] != str[i])
break;
is_pred = false;
continue;
case '(':
is_pred = false;
open++;
if (open > max_open)
max_open = open;
continue;
case ')':
is_pred = false;
if (open == 1) {
*err = i;
return TOO_MANY_CLOSE;
}
open--;
continue;
}
if (!is_pred) {
nr_preds++;
is_pred = true;
}
}
if (quote) {
*err = last_quote;
return MISSING_QUOTE;
}
if (open != 1) {
int level = open;
for (i--; i; i--) {
if (quote) {
if (str[i] == quote)
quote = 0;
continue;
}
switch (str[i]) {
case '(':
if (level == open) {
*err = i;
return TOO_MANY_OPEN;
}
level--;
break;
case ')':
level++;
break;
case '\'':
case '"':
quote = str[i];
break;
}
}
*err = 0;
return TOO_MANY_OPEN;
}
*parens = max_open;
*preds = nr_preds;
return 0;
}
static int process_preds(struct trace_event_call *call,
const char *filter_string,
struct event_filter *filter,
struct filter_parse_error *pe)
{
struct prog_entry *prog;
int nr_parens;
int nr_preds;
int index;
int ret;
ret = calc_stack(filter_string, &nr_parens, &nr_preds, &index);
if (ret < 0) {
switch (ret) {
case MISSING_QUOTE:
parse_error(pe, FILT_ERR_MISSING_QUOTE, index);
break;
case TOO_MANY_OPEN:
parse_error(pe, FILT_ERR_TOO_MANY_OPEN, index);
break;
default:
parse_error(pe, FILT_ERR_TOO_MANY_CLOSE, index);
}
return ret;
}
if (!nr_preds)
return -EINVAL;
prog = predicate_parse(filter_string, nr_parens, nr_preds,
parse_pred, call, pe);
if (IS_ERR(prog))
return PTR_ERR(prog);
rcu_assign_pointer(filter->prog, prog);
return 0;
}
static inline void event_set_filtered_flag(struct trace_event_file *file)
{
unsigned long old_flags = file->flags;
file->flags |= EVENT_FILE_FL_FILTERED;
if (old_flags != file->flags)
trace_buffered_event_enable();
}
static int process_system_preds(struct trace_subsystem_dir *dir,
struct trace_array *tr,
struct filter_parse_error *pe,
char *filter_string)
{
struct trace_event_file *file;
struct filter_list *filter_item;
struct event_filter *filter = NULL;
struct filter_head *filter_list;
bool fail = true;
int err;
filter_list = kmalloc_obj(*filter_list);
if (!filter_list)
return -ENOMEM;
INIT_LIST_HEAD(&filter_list->list);
list_for_each_entry(file, &tr->events, list) {
if (file->system != dir)
continue;
filter = kzalloc_obj(*filter);
if (!filter)
goto fail_mem;
filter->filter_string = kstrdup(filter_string, GFP_KERNEL);
if (!filter->filter_string)
goto fail_mem;
err = process_preds(file->event_call, filter_string, filter, pe);
if (err) {
filter_disable(file);
parse_error(pe, FILT_ERR_BAD_SUBSYS_FILTER, 0);
append_filter_err(tr, pe, filter);
} else
event_set_filtered_flag(file);
filter_item = kzalloc_obj(*filter_item);
if (!filter_item)
goto fail_mem;
list_add_tail(&filter_item->list, &filter_list->list);
filter_item->filter = event_filter(file);
event_set_filter(file, filter);
filter = NULL;
fail = false;
}
if (fail)
goto fail;
delay_free_filter(filter_list);
return 0;
fail:
free_filter_list(filter_list);
parse_error(pe, FILT_ERR_BAD_SUBSYS_FILTER, 0);
return -EINVAL;
fail_mem:
__free_filter(filter);
if (!fail)
delay_free_filter(filter_list);
else
free_filter_list(filter_list);
return -ENOMEM;
}
static int create_filter_start(char *filter_string, bool set_str,
struct filter_parse_error **pse,
struct event_filter **filterp)
{
struct event_filter *filter;
struct filter_parse_error *pe = NULL;
int err = 0;
if (WARN_ON_ONCE(*pse || *filterp))
return -EINVAL;
filter = kzalloc_obj(*filter);
if (filter && set_str) {
filter->filter_string = kstrdup(filter_string, GFP_KERNEL);
if (!filter->filter_string)
err = -ENOMEM;
}
pe = kzalloc_obj(*pe);
if (!filter || !pe || err) {
kfree(pe);
__free_filter(filter);
return -ENOMEM;
}
*filterp = filter;
*pse = pe;
return 0;
}
static void create_filter_finish(struct filter_parse_error *pe)
{
kfree(pe);
}
static int create_filter(struct trace_array *tr,
struct trace_event_call *call,
char *filter_string, bool set_str,
struct event_filter **filterp)
{
struct filter_parse_error *pe = NULL;
int err;
if (WARN_ON(*filterp))
*filterp = NULL;
err = create_filter_start(filter_string, set_str, &pe, filterp);
if (err)
return err;
err = process_preds(call, filter_string, *filterp, pe);
if (err && set_str)
append_filter_err(tr, pe, *filterp);
create_filter_finish(pe);
return err;
}
int create_event_filter(struct trace_array *tr,
struct trace_event_call *call,
char *filter_str, bool set_str,
struct event_filter **filterp)
{
return create_filter(tr, call, filter_str, set_str, filterp);
}
static int create_system_filter(struct trace_subsystem_dir *dir,
char *filter_str, struct event_filter **filterp)
{
struct filter_parse_error *pe = NULL;
int err;
err = create_filter_start(filter_str, true, &pe, filterp);
if (!err) {
err = process_system_preds(dir, dir->tr, pe, filter_str);
if (!err) {
kfree((*filterp)->filter_string);
(*filterp)->filter_string = NULL;
} else {
append_filter_err(dir->tr, pe, *filterp);
}
}
create_filter_finish(pe);
return err;
}
int apply_event_filter(struct trace_event_file *file, char *filter_string)
{
struct trace_event_call *call = file->event_call;
struct event_filter *filter = NULL;
int err;
if (file->flags & EVENT_FILE_FL_FREED)
return -ENODEV;
if (!strcmp(strstrip(filter_string), "0")) {
filter_disable(file);
filter = event_filter(file);
if (!filter)
return 0;
event_clear_filter(file);
try_delay_free_filter(filter);
return 0;
}
err = create_filter(file->tr, call, filter_string, true, &filter);
if (filter) {
struct event_filter *tmp;
tmp = event_filter(file);
if (!err)
event_set_filtered_flag(file);
else
filter_disable(file);
event_set_filter(file, filter);
if (tmp)
try_delay_free_filter(tmp);
}
return err;
}
int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
char *filter_string)
{
struct event_subsystem *system = dir->subsystem;
struct trace_array *tr = dir->tr;
struct event_filter *filter = NULL;
int err = 0;
guard(mutex)(&event_mutex);
if (!dir->nr_events)
return -ENODEV;
if (!strcmp(strstrip(filter_string), "0")) {
filter_free_subsystem_preds(dir, tr);
remove_filter_string(system->filter);
filter = system->filter;
system->filter = NULL;
filter_free_subsystem_filters(dir, tr, filter);
return 0;
}
err = create_system_filter(dir, filter_string, &filter);
if (filter) {
__free_filter(system->filter);
system->filter = filter;
}
return err;
}
#ifdef CONFIG_PERF_EVENTS
void ftrace_profile_free_filter(struct perf_event *event)
{
struct event_filter *filter = event->filter;
event->filter = NULL;
__free_filter(filter);
}
struct function_filter_data {
struct ftrace_ops *ops;
int first_filter;
int first_notrace;
};
#ifdef CONFIG_FUNCTION_TRACER
static char **
ftrace_function_filter_re(char *buf, int len, int *count)
{
char *str, **re;
str = kstrndup(buf, len, GFP_KERNEL);
if (!str)
return NULL;
strreplace(str, ',', ' ');
re = argv_split(GFP_KERNEL, str, count);
kfree(str);
return re;
}
static int ftrace_function_set_regexp(struct ftrace_ops *ops, int filter,
int reset, char *re, int len)
{
int ret;
if (filter)
ret = ftrace_set_filter(ops, re, len, reset);
else
ret = ftrace_set_notrace(ops, re, len, reset);
return ret;
}
static int __ftrace_function_set_filter(int filter, char *buf, int len,
struct function_filter_data *data)
{
int i, re_cnt, ret = -EINVAL;
int *reset;
char **re;
reset = filter ? &data->first_filter : &data->first_notrace;
re = ftrace_function_filter_re(buf, len, &re_cnt);
if (!re)
return -EINVAL;
for (i = 0; i < re_cnt; i++) {
ret = ftrace_function_set_regexp(data->ops, filter, *reset,
re[i], strlen(re[i]));
if (ret)
break;
if (*reset)
*reset = 0;
}
argv_free(re);
return ret;
}
static int ftrace_function_check_pred(struct filter_pred *pred)
{
struct ftrace_event_field *field = pred->field;
if ((pred->op != OP_EQ) && (pred->op != OP_NE))
return -EINVAL;
if (strcmp(field->name, "ip"))
return -EINVAL;
return 0;
}
static int ftrace_function_set_filter_pred(struct filter_pred *pred,
struct function_filter_data *data)
{
int ret;
ret = ftrace_function_check_pred(pred);
if (ret)
return ret;
return __ftrace_function_set_filter(pred->op == OP_EQ,
pred->regex->pattern,
pred->regex->len,
data);
}
static bool is_or(struct prog_entry *prog, int i)
{
int target;
target = prog[i].target + 1;
if (prog[target].pred)
return false;
return prog[i].when_to_branch == prog[target].target;
}
static int ftrace_function_set_filter(struct perf_event *event,
struct event_filter *filter)
{
struct prog_entry *prog = rcu_dereference_protected(filter->prog,
lockdep_is_held(&event_mutex));
struct function_filter_data data = {
.first_filter = 1,
.first_notrace = 1,
.ops = &event->ftrace_ops,
};
int i;
for (i = 0; prog[i].pred; i++) {
struct filter_pred *pred = prog[i].pred;
if (!is_or(prog, i))
return -EINVAL;
if (ftrace_function_set_filter_pred(pred, &data) < 0)
return -EINVAL;
}
return 0;
}
#else
static int ftrace_function_set_filter(struct perf_event *event,
struct event_filter *filter)
{
return -ENODEV;
}
#endif
int ftrace_profile_set_filter(struct perf_event *event, int event_id,
char *filter_str)
{
int err;
struct event_filter *filter = NULL;
struct trace_event_call *call;
guard(mutex)(&event_mutex);
call = event->tp_event;
if (!call)
return -EINVAL;
if (event->filter)
return -EEXIST;
err = create_filter(NULL, call, filter_str, false, &filter);
if (err)
goto free_filter;
if (ftrace_event_is_function(call))
err = ftrace_function_set_filter(event, filter);
else
event->filter = filter;
free_filter:
if (err || ftrace_event_is_function(call))
__free_filter(filter);
return err;
}
#endif
#ifdef CONFIG_FTRACE_STARTUP_TEST
#include <linux/types.h>
#include <linux/tracepoint.h>
#define CREATE_TRACE_POINTS
#include "trace_events_filter_test.h"
#define DATA_REC(m, va, vb, vc, vd, ve, vf, vg, vh, nvisit) \
{ \
.filter = FILTER, \
.rec = { .a = va, .b = vb, .c = vc, .d = vd, \
.e = ve, .f = vf, .g = vg, .h = vh }, \
.match = m, \
.not_visited = nvisit, \
}
#define YES 1
#define NO 0
static struct test_filter_data_t {
char *filter;
struct trace_event_raw_ftrace_test_filter rec;
int match;
char *not_visited;
} test_filter_data[] = {
#define FILTER "a == 1 && b == 1 && c == 1 && d == 1 && " \
"e == 1 && f == 1 && g == 1 && h == 1"
DATA_REC(YES, 1, 1, 1, 1, 1, 1, 1, 1, ""),
DATA_REC(NO, 0, 1, 1, 1, 1, 1, 1, 1, "bcdefgh"),
DATA_REC(NO, 1, 1, 1, 1, 1, 1, 1, 0, ""),
#undef FILTER
#define FILTER "a == 1 || b == 1 || c == 1 || d == 1 || " \
"e == 1 || f == 1 || g == 1 || h == 1"
DATA_REC(NO, 0, 0, 0, 0, 0, 0, 0, 0, ""),
DATA_REC(YES, 0, 0, 0, 0, 0, 0, 0, 1, ""),
DATA_REC(YES, 1, 0, 0, 0, 0, 0, 0, 0, "bcdefgh"),
#undef FILTER
#define FILTER "(a == 1 || b == 1) && (c == 1 || d == 1) && " \
"(e == 1 || f == 1) && (g == 1 || h == 1)"
DATA_REC(NO, 0, 0, 1, 1, 1, 1, 1, 1, "dfh"),
DATA_REC(YES, 0, 1, 0, 1, 0, 1, 0, 1, ""),
DATA_REC(YES, 1, 0, 1, 0, 0, 1, 0, 1, "bd"),
DATA_REC(NO, 1, 0, 1, 0, 0, 1, 0, 0, "bd"),
#undef FILTER
#define FILTER "(a == 1 && b == 1) || (c == 1 && d == 1) || " \
"(e == 1 && f == 1) || (g == 1 && h == 1)"
DATA_REC(YES, 1, 0, 1, 1, 1, 1, 1, 1, "efgh"),
DATA_REC(YES, 0, 0, 0, 0, 0, 0, 1, 1, ""),
DATA_REC(NO, 0, 0, 0, 0, 0, 0, 0, 1, ""),
#undef FILTER
#define FILTER "(a == 1 && b == 1) && (c == 1 && d == 1) && " \
"(e == 1 && f == 1) || (g == 1 && h == 1)"
DATA_REC(YES, 1, 1, 1, 1, 1, 1, 0, 0, "gh"),
DATA_REC(NO, 0, 0, 0, 0, 0, 0, 0, 1, ""),
DATA_REC(YES, 1, 1, 1, 1, 1, 0, 1, 1, ""),
#undef FILTER
#define FILTER "((a == 1 || b == 1) || (c == 1 || d == 1) || " \
"(e == 1 || f == 1)) && (g == 1 || h == 1)"
DATA_REC(YES, 1, 1, 1, 1, 1, 1, 0, 1, "bcdef"),
DATA_REC(NO, 0, 0, 0, 0, 0, 0, 0, 0, ""),
DATA_REC(YES, 1, 1, 1, 1, 1, 0, 1, 1, "h"),
#undef FILTER
#define FILTER "((((((((a == 1) && (b == 1)) || (c == 1)) && (d == 1)) || " \
"(e == 1)) && (f == 1)) || (g == 1)) && (h == 1))"
DATA_REC(YES, 1, 1, 1, 1, 1, 1, 1, 1, "ceg"),
DATA_REC(NO, 0, 1, 0, 1, 0, 1, 0, 1, ""),
DATA_REC(NO, 1, 0, 1, 0, 1, 0, 1, 0, ""),
#undef FILTER
#define FILTER "((((((((a == 1) || (b == 1)) && (c == 1)) || (d == 1)) && " \
"(e == 1)) || (f == 1)) && (g == 1)) || (h == 1))"
DATA_REC(YES, 1, 1, 1, 1, 1, 1, 1, 1, "bdfh"),
DATA_REC(YES, 0, 1, 0, 1, 0, 1, 0, 1, ""),
DATA_REC(YES, 1, 0, 1, 0, 1, 0, 1, 0, "bdfh"),
};
#undef DATA_REC
#undef FILTER
#undef YES
#undef NO
#define DATA_CNT ARRAY_SIZE(test_filter_data)
static int test_pred_visited;
static int test_pred_visited_fn(struct filter_pred *pred, void *event)
{
struct ftrace_event_field *field = pred->field;
test_pred_visited = 1;
printk(KERN_INFO "\npred visited %s\n", field->name);
return 1;
}
static void update_pred_fn(struct event_filter *filter, char *fields)
{
struct prog_entry *prog = rcu_dereference_protected(filter->prog,
lockdep_is_held(&event_mutex));
int i;
for (i = 0; prog[i].pred; i++) {
struct filter_pred *pred = prog[i].pred;
struct ftrace_event_field *field = pred->field;
WARN_ON_ONCE(pred->fn_num == FILTER_PRED_FN_NOP);
if (!field) {
WARN_ONCE(1, "all leafs should have field defined %d", i);
continue;
}
if (!strchr(fields, *field->name))
continue;
pred->fn_num = FILTER_PRED_TEST_VISITED;
}
}
static __init int ftrace_test_event_filter(void)
{
int i;
printk(KERN_INFO "Testing ftrace filter: ");
for (i = 0; i < DATA_CNT; i++) {
struct event_filter *filter = NULL;
struct test_filter_data_t *d = &test_filter_data[i];
int err;
err = create_filter(NULL, &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;
}
mutex_lock(&event_mutex);
preempt_disable();
if (*d->not_visited)
update_pred_fn(filter, d->not_visited);
test_pred_visited = 0;
err = filter_match_preds(filter, &d->rec);
preempt_enable();
mutex_unlock(&event_mutex);
__free_filter(filter);
if (test_pred_visited) {
printk(KERN_INFO
"Failed, unwanted pred visited for filter %s\n",
d->filter);
break;
}
if (err != d->match) {
printk(KERN_INFO
"Failed to match filter '%s', expected %d\n",
d->filter, d->match);
break;
}
}
if (i == DATA_CNT)
printk(KERN_CONT "OK\n");
if (!trace_ftrace_test_filter_enabled())
trace_ftrace_test_filter(1, 2, 3, 4, 5, 6, 7, 8);
return 0;
}
late_initcall(ftrace_test_event_filter);
#endif
