linux/kernel/trace/trace_events_hist.c

1757 lines
41 KiB
C

/*
* trace_events_hist - trace event hist triggers
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* Copyright (C) 2015 Tom Zanussi <tom.zanussi@linux.intel.com>
*/
#include <linux/module.h>
#include <linux/kallsyms.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/stacktrace.h>
#include <linux/rculist.h>
#include "tracing_map.h"
#include "trace.h"
struct hist_field;
typedef u64 (*hist_field_fn_t) (struct hist_field *field, void *event);
struct hist_field {
struct ftrace_event_field *field;
unsigned long flags;
hist_field_fn_t fn;
unsigned int size;
unsigned int offset;
};
static u64 hist_field_none(struct hist_field *field, void *event)
{
return 0;
}
static u64 hist_field_counter(struct hist_field *field, void *event)
{
return 1;
}
static u64 hist_field_string(struct hist_field *hist_field, void *event)
{
char *addr = (char *)(event + hist_field->field->offset);
return (u64)(unsigned long)addr;
}
static u64 hist_field_dynstring(struct hist_field *hist_field, void *event)
{
u32 str_item = *(u32 *)(event + hist_field->field->offset);
int str_loc = str_item & 0xffff;
char *addr = (char *)(event + str_loc);
return (u64)(unsigned long)addr;
}
static u64 hist_field_pstring(struct hist_field *hist_field, void *event)
{
char **addr = (char **)(event + hist_field->field->offset);
return (u64)(unsigned long)*addr;
}
static u64 hist_field_log2(struct hist_field *hist_field, void *event)
{
u64 val = *(u64 *)(event + hist_field->field->offset);
return (u64) ilog2(roundup_pow_of_two(val));
}
#define DEFINE_HIST_FIELD_FN(type) \
static u64 hist_field_##type(struct hist_field *hist_field, void *event)\
{ \
type *addr = (type *)(event + hist_field->field->offset); \
\
return (u64)(unsigned long)*addr; \
}
DEFINE_HIST_FIELD_FN(s64);
DEFINE_HIST_FIELD_FN(u64);
DEFINE_HIST_FIELD_FN(s32);
DEFINE_HIST_FIELD_FN(u32);
DEFINE_HIST_FIELD_FN(s16);
DEFINE_HIST_FIELD_FN(u16);
DEFINE_HIST_FIELD_FN(s8);
DEFINE_HIST_FIELD_FN(u8);
#define for_each_hist_field(i, hist_data) \
for ((i) = 0; (i) < (hist_data)->n_fields; (i)++)
#define for_each_hist_val_field(i, hist_data) \
for ((i) = 0; (i) < (hist_data)->n_vals; (i)++)
#define for_each_hist_key_field(i, hist_data) \
for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++)
#define HIST_STACKTRACE_DEPTH 16
#define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long))
#define HIST_STACKTRACE_SKIP 5
#define HITCOUNT_IDX 0
#define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE)
enum hist_field_flags {
HIST_FIELD_FL_HITCOUNT = 1,
HIST_FIELD_FL_KEY = 2,
HIST_FIELD_FL_STRING = 4,
HIST_FIELD_FL_HEX = 8,
HIST_FIELD_FL_SYM = 16,
HIST_FIELD_FL_SYM_OFFSET = 32,
HIST_FIELD_FL_EXECNAME = 64,
HIST_FIELD_FL_SYSCALL = 128,
HIST_FIELD_FL_STACKTRACE = 256,
HIST_FIELD_FL_LOG2 = 512,
};
struct hist_trigger_attrs {
char *keys_str;
char *vals_str;
char *sort_key_str;
char *name;
bool pause;
bool cont;
bool clear;
unsigned int map_bits;
};
struct hist_trigger_data {
struct hist_field *fields[TRACING_MAP_FIELDS_MAX];
unsigned int n_vals;
unsigned int n_keys;
unsigned int n_fields;
unsigned int key_size;
struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX];
unsigned int n_sort_keys;
struct trace_event_file *event_file;
struct hist_trigger_attrs *attrs;
struct tracing_map *map;
};
static hist_field_fn_t select_value_fn(int field_size, int field_is_signed)
{
hist_field_fn_t fn = NULL;
switch (field_size) {
case 8:
if (field_is_signed)
fn = hist_field_s64;
else
fn = hist_field_u64;
break;
case 4:
if (field_is_signed)
fn = hist_field_s32;
else
fn = hist_field_u32;
break;
case 2:
if (field_is_signed)
fn = hist_field_s16;
else
fn = hist_field_u16;
break;
case 1:
if (field_is_signed)
fn = hist_field_s8;
else
fn = hist_field_u8;
break;
}
return fn;
}
static int parse_map_size(char *str)
{
unsigned long size, map_bits;
int ret;
strsep(&str, "=");
if (!str) {
ret = -EINVAL;
goto out;
}
ret = kstrtoul(str, 0, &size);
if (ret)
goto out;
map_bits = ilog2(roundup_pow_of_two(size));
if (map_bits < TRACING_MAP_BITS_MIN ||
map_bits > TRACING_MAP_BITS_MAX)
ret = -EINVAL;
else
ret = map_bits;
out:
return ret;
}
static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs)
{
if (!attrs)
return;
kfree(attrs->name);
kfree(attrs->sort_key_str);
kfree(attrs->keys_str);
kfree(attrs->vals_str);
kfree(attrs);
}
static struct hist_trigger_attrs *parse_hist_trigger_attrs(char *trigger_str)
{
struct hist_trigger_attrs *attrs;
int ret = 0;
attrs = kzalloc(sizeof(*attrs), GFP_KERNEL);
if (!attrs)
return ERR_PTR(-ENOMEM);
while (trigger_str) {
char *str = strsep(&trigger_str, ":");
if ((strncmp(str, "key=", strlen("key=")) == 0) ||
(strncmp(str, "keys=", strlen("keys=")) == 0))
attrs->keys_str = kstrdup(str, GFP_KERNEL);
else if ((strncmp(str, "val=", strlen("val=")) == 0) ||
(strncmp(str, "vals=", strlen("vals=")) == 0) ||
(strncmp(str, "values=", strlen("values=")) == 0))
attrs->vals_str = kstrdup(str, GFP_KERNEL);
else if (strncmp(str, "sort=", strlen("sort=")) == 0)
attrs->sort_key_str = kstrdup(str, GFP_KERNEL);
else if (strncmp(str, "name=", strlen("name=")) == 0)
attrs->name = kstrdup(str, GFP_KERNEL);
else if (strcmp(str, "pause") == 0)
attrs->pause = true;
else if ((strcmp(str, "cont") == 0) ||
(strcmp(str, "continue") == 0))
attrs->cont = true;
else if (strcmp(str, "clear") == 0)
attrs->clear = true;
else if (strncmp(str, "size=", strlen("size=")) == 0) {
int map_bits = parse_map_size(str);
if (map_bits < 0) {
ret = map_bits;
goto free;
}
attrs->map_bits = map_bits;
} else {
ret = -EINVAL;
goto free;
}
}
if (!attrs->keys_str) {
ret = -EINVAL;
goto free;
}
return attrs;
free:
destroy_hist_trigger_attrs(attrs);
return ERR_PTR(ret);
}
static inline void save_comm(char *comm, struct task_struct *task)
{
if (!task->pid) {
strcpy(comm, "<idle>");
return;
}
if (WARN_ON_ONCE(task->pid < 0)) {
strcpy(comm, "<XXX>");
return;
}
memcpy(comm, task->comm, TASK_COMM_LEN);
}
static void hist_trigger_elt_comm_free(struct tracing_map_elt *elt)
{
kfree((char *)elt->private_data);
}
static int hist_trigger_elt_comm_alloc(struct tracing_map_elt *elt)
{
struct hist_trigger_data *hist_data = elt->map->private_data;
struct hist_field *key_field;
unsigned int i;
for_each_hist_key_field(i, hist_data) {
key_field = hist_data->fields[i];
if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
unsigned int size = TASK_COMM_LEN + 1;
elt->private_data = kzalloc(size, GFP_KERNEL);
if (!elt->private_data)
return -ENOMEM;
break;
}
}
return 0;
}
static void hist_trigger_elt_comm_copy(struct tracing_map_elt *to,
struct tracing_map_elt *from)
{
char *comm_from = from->private_data;
char *comm_to = to->private_data;
if (comm_from)
memcpy(comm_to, comm_from, TASK_COMM_LEN + 1);
}
static void hist_trigger_elt_comm_init(struct tracing_map_elt *elt)
{
char *comm = elt->private_data;
if (comm)
save_comm(comm, current);
}
static const struct tracing_map_ops hist_trigger_elt_comm_ops = {
.elt_alloc = hist_trigger_elt_comm_alloc,
.elt_copy = hist_trigger_elt_comm_copy,
.elt_free = hist_trigger_elt_comm_free,
.elt_init = hist_trigger_elt_comm_init,
};
static void destroy_hist_field(struct hist_field *hist_field)
{
kfree(hist_field);
}
static struct hist_field *create_hist_field(struct ftrace_event_field *field,
unsigned long flags)
{
struct hist_field *hist_field;
if (field && is_function_field(field))
return NULL;
hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL);
if (!hist_field)
return NULL;
if (flags & HIST_FIELD_FL_HITCOUNT) {
hist_field->fn = hist_field_counter;
goto out;
}
if (flags & HIST_FIELD_FL_STACKTRACE) {
hist_field->fn = hist_field_none;
goto out;
}
if (flags & HIST_FIELD_FL_LOG2) {
hist_field->fn = hist_field_log2;
goto out;
}
if (WARN_ON_ONCE(!field))
goto out;
if (is_string_field(field)) {
flags |= HIST_FIELD_FL_STRING;
if (field->filter_type == FILTER_STATIC_STRING)
hist_field->fn = hist_field_string;
else if (field->filter_type == FILTER_DYN_STRING)
hist_field->fn = hist_field_dynstring;
else
hist_field->fn = hist_field_pstring;
} else {
hist_field->fn = select_value_fn(field->size,
field->is_signed);
if (!hist_field->fn) {
destroy_hist_field(hist_field);
return NULL;
}
}
out:
hist_field->field = field;
hist_field->flags = flags;
return hist_field;
}
static void destroy_hist_fields(struct hist_trigger_data *hist_data)
{
unsigned int i;
for (i = 0; i < TRACING_MAP_FIELDS_MAX; i++) {
if (hist_data->fields[i]) {
destroy_hist_field(hist_data->fields[i]);
hist_data->fields[i] = NULL;
}
}
}
static int create_hitcount_val(struct hist_trigger_data *hist_data)
{
hist_data->fields[HITCOUNT_IDX] =
create_hist_field(NULL, HIST_FIELD_FL_HITCOUNT);
if (!hist_data->fields[HITCOUNT_IDX])
return -ENOMEM;
hist_data->n_vals++;
if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX))
return -EINVAL;
return 0;
}
static int create_val_field(struct hist_trigger_data *hist_data,
unsigned int val_idx,
struct trace_event_file *file,
char *field_str)
{
struct ftrace_event_field *field = NULL;
unsigned long flags = 0;
char *field_name;
int ret = 0;
if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX))
return -EINVAL;
field_name = strsep(&field_str, ".");
if (field_str) {
if (strcmp(field_str, "hex") == 0)
flags |= HIST_FIELD_FL_HEX;
else {
ret = -EINVAL;
goto out;
}
}
field = trace_find_event_field(file->event_call, field_name);
if (!field) {
ret = -EINVAL;
goto out;
}
hist_data->fields[val_idx] = create_hist_field(field, flags);
if (!hist_data->fields[val_idx]) {
ret = -ENOMEM;
goto out;
}
++hist_data->n_vals;
if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX))
ret = -EINVAL;
out:
return ret;
}
static int create_val_fields(struct hist_trigger_data *hist_data,
struct trace_event_file *file)
{
char *fields_str, *field_str;
unsigned int i, j;
int ret;
ret = create_hitcount_val(hist_data);
if (ret)
goto out;
fields_str = hist_data->attrs->vals_str;
if (!fields_str)
goto out;
strsep(&fields_str, "=");
if (!fields_str)
goto out;
for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX &&
j < TRACING_MAP_VALS_MAX; i++) {
field_str = strsep(&fields_str, ",");
if (!field_str)
break;
if (strcmp(field_str, "hitcount") == 0)
continue;
ret = create_val_field(hist_data, j++, file, field_str);
if (ret)
goto out;
}
if (fields_str && (strcmp(fields_str, "hitcount") != 0))
ret = -EINVAL;
out:
return ret;
}
static int create_key_field(struct hist_trigger_data *hist_data,
unsigned int key_idx,
unsigned int key_offset,
struct trace_event_file *file,
char *field_str)
{
struct ftrace_event_field *field = NULL;
unsigned long flags = 0;
unsigned int key_size;
int ret = 0;
if (WARN_ON(key_idx >= TRACING_MAP_FIELDS_MAX))
return -EINVAL;
flags |= HIST_FIELD_FL_KEY;
if (strcmp(field_str, "stacktrace") == 0) {
flags |= HIST_FIELD_FL_STACKTRACE;
key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH;
} else {
char *field_name = strsep(&field_str, ".");
if (field_str) {
if (strcmp(field_str, "hex") == 0)
flags |= HIST_FIELD_FL_HEX;
else if (strcmp(field_str, "sym") == 0)
flags |= HIST_FIELD_FL_SYM;
else if (strcmp(field_str, "sym-offset") == 0)
flags |= HIST_FIELD_FL_SYM_OFFSET;
else if ((strcmp(field_str, "execname") == 0) &&
(strcmp(field_name, "common_pid") == 0))
flags |= HIST_FIELD_FL_EXECNAME;
else if (strcmp(field_str, "syscall") == 0)
flags |= HIST_FIELD_FL_SYSCALL;
else if (strcmp(field_str, "log2") == 0)
flags |= HIST_FIELD_FL_LOG2;
else {
ret = -EINVAL;
goto out;
}
}
field = trace_find_event_field(file->event_call, field_name);
if (!field) {
ret = -EINVAL;
goto out;
}
if (is_string_field(field))
key_size = MAX_FILTER_STR_VAL;
else
key_size = field->size;
}
hist_data->fields[key_idx] = create_hist_field(field, flags);
if (!hist_data->fields[key_idx]) {
ret = -ENOMEM;
goto out;
}
key_size = ALIGN(key_size, sizeof(u64));
hist_data->fields[key_idx]->size = key_size;
hist_data->fields[key_idx]->offset = key_offset;
hist_data->key_size += key_size;
if (hist_data->key_size > HIST_KEY_SIZE_MAX) {
ret = -EINVAL;
goto out;
}
hist_data->n_keys++;
if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX))
return -EINVAL;
ret = key_size;
out:
return ret;
}
static int create_key_fields(struct hist_trigger_data *hist_data,
struct trace_event_file *file)
{
unsigned int i, key_offset = 0, n_vals = hist_data->n_vals;
char *fields_str, *field_str;
int ret = -EINVAL;
fields_str = hist_data->attrs->keys_str;
if (!fields_str)
goto out;
strsep(&fields_str, "=");
if (!fields_str)
goto out;
for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) {
field_str = strsep(&fields_str, ",");
if (!field_str)
break;
ret = create_key_field(hist_data, i, key_offset,
file, field_str);
if (ret < 0)
goto out;
key_offset += ret;
}
if (fields_str) {
ret = -EINVAL;
goto out;
}
ret = 0;
out:
return ret;
}
static int create_hist_fields(struct hist_trigger_data *hist_data,
struct trace_event_file *file)
{
int ret;
ret = create_val_fields(hist_data, file);
if (ret)
goto out;
ret = create_key_fields(hist_data, file);
if (ret)
goto out;
hist_data->n_fields = hist_data->n_vals + hist_data->n_keys;
out:
return ret;
}
static int is_descending(const char *str)
{
if (!str)
return 0;
if (strcmp(str, "descending") == 0)
return 1;
if (strcmp(str, "ascending") == 0)
return 0;
return -EINVAL;
}
static int create_sort_keys(struct hist_trigger_data *hist_data)
{
char *fields_str = hist_data->attrs->sort_key_str;
struct ftrace_event_field *field = NULL;
struct tracing_map_sort_key *sort_key;
int descending, ret = 0;
unsigned int i, j;
hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */
if (!fields_str)
goto out;
strsep(&fields_str, "=");
if (!fields_str) {
ret = -EINVAL;
goto out;
}
for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) {
char *field_str, *field_name;
sort_key = &hist_data->sort_keys[i];
field_str = strsep(&fields_str, ",");
if (!field_str) {
if (i == 0)
ret = -EINVAL;
break;
}
if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) {
ret = -EINVAL;
break;
}
field_name = strsep(&field_str, ".");
if (!field_name) {
ret = -EINVAL;
break;
}
if (strcmp(field_name, "hitcount") == 0) {
descending = is_descending(field_str);
if (descending < 0) {
ret = descending;
break;
}
sort_key->descending = descending;
continue;
}
for (j = 1; j < hist_data->n_fields; j++) {
field = hist_data->fields[j]->field;
if (field && (strcmp(field_name, field->name) == 0)) {
sort_key->field_idx = j;
descending = is_descending(field_str);
if (descending < 0) {
ret = descending;
goto out;
}
sort_key->descending = descending;
break;
}
}
if (j == hist_data->n_fields) {
ret = -EINVAL;
break;
}
}
hist_data->n_sort_keys = i;
out:
return ret;
}
static void destroy_hist_data(struct hist_trigger_data *hist_data)
{
destroy_hist_trigger_attrs(hist_data->attrs);
destroy_hist_fields(hist_data);
tracing_map_destroy(hist_data->map);
kfree(hist_data);
}
static int create_tracing_map_fields(struct hist_trigger_data *hist_data)
{
struct tracing_map *map = hist_data->map;
struct ftrace_event_field *field;
struct hist_field *hist_field;
int i, idx;
for_each_hist_field(i, hist_data) {
hist_field = hist_data->fields[i];
if (hist_field->flags & HIST_FIELD_FL_KEY) {
tracing_map_cmp_fn_t cmp_fn;
field = hist_field->field;
if (hist_field->flags & HIST_FIELD_FL_STACKTRACE)
cmp_fn = tracing_map_cmp_none;
else if (is_string_field(field))
cmp_fn = tracing_map_cmp_string;
else
cmp_fn = tracing_map_cmp_num(field->size,
field->is_signed);
idx = tracing_map_add_key_field(map,
hist_field->offset,
cmp_fn);
} else
idx = tracing_map_add_sum_field(map);
if (idx < 0)
return idx;
}
return 0;
}
static bool need_tracing_map_ops(struct hist_trigger_data *hist_data)
{
struct hist_field *key_field;
unsigned int i;
for_each_hist_key_field(i, hist_data) {
key_field = hist_data->fields[i];
if (key_field->flags & HIST_FIELD_FL_EXECNAME)
return true;
}
return false;
}
static struct hist_trigger_data *
create_hist_data(unsigned int map_bits,
struct hist_trigger_attrs *attrs,
struct trace_event_file *file)
{
const struct tracing_map_ops *map_ops = NULL;
struct hist_trigger_data *hist_data;
int ret = 0;
hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL);
if (!hist_data)
return ERR_PTR(-ENOMEM);
hist_data->attrs = attrs;
ret = create_hist_fields(hist_data, file);
if (ret)
goto free;
ret = create_sort_keys(hist_data);
if (ret)
goto free;
if (need_tracing_map_ops(hist_data))
map_ops = &hist_trigger_elt_comm_ops;
hist_data->map = tracing_map_create(map_bits, hist_data->key_size,
map_ops, hist_data);
if (IS_ERR(hist_data->map)) {
ret = PTR_ERR(hist_data->map);
hist_data->map = NULL;
goto free;
}
ret = create_tracing_map_fields(hist_data);
if (ret)
goto free;
ret = tracing_map_init(hist_data->map);
if (ret)
goto free;
hist_data->event_file = file;
out:
return hist_data;
free:
hist_data->attrs = NULL;
destroy_hist_data(hist_data);
hist_data = ERR_PTR(ret);
goto out;
}
static void hist_trigger_elt_update(struct hist_trigger_data *hist_data,
struct tracing_map_elt *elt,
void *rec)
{
struct hist_field *hist_field;
unsigned int i;
u64 hist_val;
for_each_hist_val_field(i, hist_data) {
hist_field = hist_data->fields[i];
hist_val = hist_field->fn(hist_field, rec);
tracing_map_update_sum(elt, i, hist_val);
}
}
static inline void add_to_key(char *compound_key, void *key,
struct hist_field *key_field, void *rec)
{
size_t size = key_field->size;
if (key_field->flags & HIST_FIELD_FL_STRING) {
struct ftrace_event_field *field;
field = key_field->field;
if (field->filter_type == FILTER_DYN_STRING)
size = *(u32 *)(rec + field->offset) >> 16;
else if (field->filter_type == FILTER_PTR_STRING)
size = strlen(key);
else if (field->filter_type == FILTER_STATIC_STRING)
size = field->size;
/* ensure NULL-termination */
if (size > key_field->size - 1)
size = key_field->size - 1;
}
memcpy(compound_key + key_field->offset, key, size);
}
static void event_hist_trigger(struct event_trigger_data *data, void *rec)
{
struct hist_trigger_data *hist_data = data->private_data;
bool use_compound_key = (hist_data->n_keys > 1);
unsigned long entries[HIST_STACKTRACE_DEPTH];
char compound_key[HIST_KEY_SIZE_MAX];
struct stack_trace stacktrace;
struct hist_field *key_field;
struct tracing_map_elt *elt;
u64 field_contents;
void *key = NULL;
unsigned int i;
memset(compound_key, 0, hist_data->key_size);
for_each_hist_key_field(i, hist_data) {
key_field = hist_data->fields[i];
if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
stacktrace.max_entries = HIST_STACKTRACE_DEPTH;
stacktrace.entries = entries;
stacktrace.nr_entries = 0;
stacktrace.skip = HIST_STACKTRACE_SKIP;
memset(stacktrace.entries, 0, HIST_STACKTRACE_SIZE);
save_stack_trace(&stacktrace);
key = entries;
} else {
field_contents = key_field->fn(key_field, rec);
if (key_field->flags & HIST_FIELD_FL_STRING) {
key = (void *)(unsigned long)field_contents;
use_compound_key = true;
} else
key = (void *)&field_contents;
}
if (use_compound_key)
add_to_key(compound_key, key, key_field, rec);
}
if (use_compound_key)
key = compound_key;
elt = tracing_map_insert(hist_data->map, key);
if (elt)
hist_trigger_elt_update(hist_data, elt, rec);
}
static void hist_trigger_stacktrace_print(struct seq_file *m,
unsigned long *stacktrace_entries,
unsigned int max_entries)
{
char str[KSYM_SYMBOL_LEN];
unsigned int spaces = 8;
unsigned int i;
for (i = 0; i < max_entries; i++) {
if (stacktrace_entries[i] == ULONG_MAX)
return;
seq_printf(m, "%*c", 1 + spaces, ' ');
sprint_symbol(str, stacktrace_entries[i]);
seq_printf(m, "%s\n", str);
}
}
static void
hist_trigger_entry_print(struct seq_file *m,
struct hist_trigger_data *hist_data, void *key,
struct tracing_map_elt *elt)
{
struct hist_field *key_field;
char str[KSYM_SYMBOL_LEN];
bool multiline = false;
unsigned int i;
u64 uval;
seq_puts(m, "{ ");
for_each_hist_key_field(i, hist_data) {
key_field = hist_data->fields[i];
if (i > hist_data->n_vals)
seq_puts(m, ", ");
if (key_field->flags & HIST_FIELD_FL_HEX) {
uval = *(u64 *)(key + key_field->offset);
seq_printf(m, "%s: %llx",
key_field->field->name, uval);
} else if (key_field->flags & HIST_FIELD_FL_SYM) {
uval = *(u64 *)(key + key_field->offset);
sprint_symbol_no_offset(str, uval);
seq_printf(m, "%s: [%llx] %-45s",
key_field->field->name, uval, str);
} else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) {
uval = *(u64 *)(key + key_field->offset);
sprint_symbol(str, uval);
seq_printf(m, "%s: [%llx] %-55s",
key_field->field->name, uval, str);
} else if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
char *comm = elt->private_data;
uval = *(u64 *)(key + key_field->offset);
seq_printf(m, "%s: %-16s[%10llu]",
key_field->field->name, comm, uval);
} else if (key_field->flags & HIST_FIELD_FL_SYSCALL) {
const char *syscall_name;
uval = *(u64 *)(key + key_field->offset);
syscall_name = get_syscall_name(uval);
if (!syscall_name)
syscall_name = "unknown_syscall";
seq_printf(m, "%s: %-30s[%3llu]",
key_field->field->name, syscall_name, uval);
} else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
seq_puts(m, "stacktrace:\n");
hist_trigger_stacktrace_print(m,
key + key_field->offset,
HIST_STACKTRACE_DEPTH);
multiline = true;
} else if (key_field->flags & HIST_FIELD_FL_LOG2) {
seq_printf(m, "%s: ~ 2^%-2llu", key_field->field->name,
*(u64 *)(key + key_field->offset));
} else if (key_field->flags & HIST_FIELD_FL_STRING) {
seq_printf(m, "%s: %-50s", key_field->field->name,
(char *)(key + key_field->offset));
} else {
uval = *(u64 *)(key + key_field->offset);
seq_printf(m, "%s: %10llu", key_field->field->name,
uval);
}
}
if (!multiline)
seq_puts(m, " ");
seq_puts(m, "}");
seq_printf(m, " hitcount: %10llu",
tracing_map_read_sum(elt, HITCOUNT_IDX));
for (i = 1; i < hist_data->n_vals; i++) {
if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) {
seq_printf(m, " %s: %10llx",
hist_data->fields[i]->field->name,
tracing_map_read_sum(elt, i));
} else {
seq_printf(m, " %s: %10llu",
hist_data->fields[i]->field->name,
tracing_map_read_sum(elt, i));
}
}
seq_puts(m, "\n");
}
static int print_entries(struct seq_file *m,
struct hist_trigger_data *hist_data)
{
struct tracing_map_sort_entry **sort_entries = NULL;
struct tracing_map *map = hist_data->map;
int i, n_entries;
n_entries = tracing_map_sort_entries(map, hist_data->sort_keys,
hist_data->n_sort_keys,
&sort_entries);
if (n_entries < 0)
return n_entries;
for (i = 0; i < n_entries; i++)
hist_trigger_entry_print(m, hist_data,
sort_entries[i]->key,
sort_entries[i]->elt);
tracing_map_destroy_sort_entries(sort_entries, n_entries);
return n_entries;
}
static void hist_trigger_show(struct seq_file *m,
struct event_trigger_data *data, int n)
{
struct hist_trigger_data *hist_data;
int n_entries, ret = 0;
if (n > 0)
seq_puts(m, "\n\n");
seq_puts(m, "# event histogram\n#\n# trigger info: ");
data->ops->print(m, data->ops, data);
seq_puts(m, "#\n\n");
hist_data = data->private_data;
n_entries = print_entries(m, hist_data);
if (n_entries < 0) {
ret = n_entries;
n_entries = 0;
}
seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n",
(u64)atomic64_read(&hist_data->map->hits),
n_entries, (u64)atomic64_read(&hist_data->map->drops));
}
static int hist_show(struct seq_file *m, void *v)
{
struct event_trigger_data *data;
struct trace_event_file *event_file;
int n = 0, ret = 0;
mutex_lock(&event_mutex);
event_file = event_file_data(m->private);
if (unlikely(!event_file)) {
ret = -ENODEV;
goto out_unlock;
}
list_for_each_entry_rcu(data, &event_file->triggers, list) {
if (data->cmd_ops->trigger_type == ETT_EVENT_HIST)
hist_trigger_show(m, data, n++);
}
out_unlock:
mutex_unlock(&event_mutex);
return ret;
}
static int event_hist_open(struct inode *inode, struct file *file)
{
return single_open(file, hist_show, file);
}
const struct file_operations event_hist_fops = {
.open = event_hist_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static const char *get_hist_field_flags(struct hist_field *hist_field)
{
const char *flags_str = NULL;
if (hist_field->flags & HIST_FIELD_FL_HEX)
flags_str = "hex";
else if (hist_field->flags & HIST_FIELD_FL_SYM)
flags_str = "sym";
else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET)
flags_str = "sym-offset";
else if (hist_field->flags & HIST_FIELD_FL_EXECNAME)
flags_str = "execname";
else if (hist_field->flags & HIST_FIELD_FL_SYSCALL)
flags_str = "syscall";
else if (hist_field->flags & HIST_FIELD_FL_LOG2)
flags_str = "log2";
return flags_str;
}
static void hist_field_print(struct seq_file *m, struct hist_field *hist_field)
{
seq_printf(m, "%s", hist_field->field->name);
if (hist_field->flags) {
const char *flags_str = get_hist_field_flags(hist_field);
if (flags_str)
seq_printf(m, ".%s", flags_str);
}
}
static int event_hist_trigger_print(struct seq_file *m,
struct event_trigger_ops *ops,
struct event_trigger_data *data)
{
struct hist_trigger_data *hist_data = data->private_data;
struct hist_field *key_field;
unsigned int i;
seq_puts(m, "hist:");
if (data->name)
seq_printf(m, "%s:", data->name);
seq_puts(m, "keys=");
for_each_hist_key_field(i, hist_data) {
key_field = hist_data->fields[i];
if (i > hist_data->n_vals)
seq_puts(m, ",");
if (key_field->flags & HIST_FIELD_FL_STACKTRACE)
seq_puts(m, "stacktrace");
else
hist_field_print(m, key_field);
}
seq_puts(m, ":vals=");
for_each_hist_val_field(i, hist_data) {
if (i == HITCOUNT_IDX)
seq_puts(m, "hitcount");
else {
seq_puts(m, ",");
hist_field_print(m, hist_data->fields[i]);
}
}
seq_puts(m, ":sort=");
for (i = 0; i < hist_data->n_sort_keys; i++) {
struct tracing_map_sort_key *sort_key;
sort_key = &hist_data->sort_keys[i];
if (i > 0)
seq_puts(m, ",");
if (sort_key->field_idx == HITCOUNT_IDX)
seq_puts(m, "hitcount");
else {
unsigned int idx = sort_key->field_idx;
if (WARN_ON(idx >= TRACING_MAP_FIELDS_MAX))
return -EINVAL;
hist_field_print(m, hist_data->fields[idx]);
}
if (sort_key->descending)
seq_puts(m, ".descending");
}
seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits));
if (data->filter_str)
seq_printf(m, " if %s", data->filter_str);
if (data->paused)
seq_puts(m, " [paused]");
else
seq_puts(m, " [active]");
seq_putc(m, '\n');
return 0;
}
static int event_hist_trigger_init(struct event_trigger_ops *ops,
struct event_trigger_data *data)
{
struct hist_trigger_data *hist_data = data->private_data;
if (!data->ref && hist_data->attrs->name)
save_named_trigger(hist_data->attrs->name, data);
data->ref++;
return 0;
}
static void event_hist_trigger_free(struct event_trigger_ops *ops,
struct event_trigger_data *data)
{
struct hist_trigger_data *hist_data = data->private_data;
if (WARN_ON_ONCE(data->ref <= 0))
return;
data->ref--;
if (!data->ref) {
if (data->name)
del_named_trigger(data);
trigger_data_free(data);
destroy_hist_data(hist_data);
}
}
static struct event_trigger_ops event_hist_trigger_ops = {
.func = event_hist_trigger,
.print = event_hist_trigger_print,
.init = event_hist_trigger_init,
.free = event_hist_trigger_free,
};
static int event_hist_trigger_named_init(struct event_trigger_ops *ops,
struct event_trigger_data *data)
{
data->ref++;
save_named_trigger(data->named_data->name, data);
event_hist_trigger_init(ops, data->named_data);
return 0;
}
static void event_hist_trigger_named_free(struct event_trigger_ops *ops,
struct event_trigger_data *data)
{
if (WARN_ON_ONCE(data->ref <= 0))
return;
event_hist_trigger_free(ops, data->named_data);
data->ref--;
if (!data->ref) {
del_named_trigger(data);
trigger_data_free(data);
}
}
static struct event_trigger_ops event_hist_trigger_named_ops = {
.func = event_hist_trigger,
.print = event_hist_trigger_print,
.init = event_hist_trigger_named_init,
.free = event_hist_trigger_named_free,
};
static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd,
char *param)
{
return &event_hist_trigger_ops;
}
static void hist_clear(struct event_trigger_data *data)
{
struct hist_trigger_data *hist_data = data->private_data;
if (data->name)
pause_named_trigger(data);
synchronize_sched();
tracing_map_clear(hist_data->map);
if (data->name)
unpause_named_trigger(data);
}
static bool compatible_field(struct ftrace_event_field *field,
struct ftrace_event_field *test_field)
{
if (field == test_field)
return true;
if (field == NULL || test_field == NULL)
return false;
if (strcmp(field->name, test_field->name) != 0)
return false;
if (strcmp(field->type, test_field->type) != 0)
return false;
if (field->size != test_field->size)
return false;
if (field->is_signed != test_field->is_signed)
return false;
return true;
}
static bool hist_trigger_match(struct event_trigger_data *data,
struct event_trigger_data *data_test,
struct event_trigger_data *named_data,
bool ignore_filter)
{
struct tracing_map_sort_key *sort_key, *sort_key_test;
struct hist_trigger_data *hist_data, *hist_data_test;
struct hist_field *key_field, *key_field_test;
unsigned int i;
if (named_data && (named_data != data_test) &&
(named_data != data_test->named_data))
return false;
if (!named_data && is_named_trigger(data_test))
return false;
hist_data = data->private_data;
hist_data_test = data_test->private_data;
if (hist_data->n_vals != hist_data_test->n_vals ||
hist_data->n_fields != hist_data_test->n_fields ||
hist_data->n_sort_keys != hist_data_test->n_sort_keys)
return false;
if (!ignore_filter) {
if ((data->filter_str && !data_test->filter_str) ||
(!data->filter_str && data_test->filter_str))
return false;
}
for_each_hist_field(i, hist_data) {
key_field = hist_data->fields[i];
key_field_test = hist_data_test->fields[i];
if (key_field->flags != key_field_test->flags)
return false;
if (!compatible_field(key_field->field, key_field_test->field))
return false;
if (key_field->offset != key_field_test->offset)
return false;
}
for (i = 0; i < hist_data->n_sort_keys; i++) {
sort_key = &hist_data->sort_keys[i];
sort_key_test = &hist_data_test->sort_keys[i];
if (sort_key->field_idx != sort_key_test->field_idx ||
sort_key->descending != sort_key_test->descending)
return false;
}
if (!ignore_filter && data->filter_str &&
(strcmp(data->filter_str, data_test->filter_str) != 0))
return false;
return true;
}
static int hist_register_trigger(char *glob, struct event_trigger_ops *ops,
struct event_trigger_data *data,
struct trace_event_file *file)
{
struct hist_trigger_data *hist_data = data->private_data;
struct event_trigger_data *test, *named_data = NULL;
int ret = 0;
if (hist_data->attrs->name) {
named_data = find_named_trigger(hist_data->attrs->name);
if (named_data) {
if (!hist_trigger_match(data, named_data, named_data,
true)) {
ret = -EINVAL;
goto out;
}
}
}
if (hist_data->attrs->name && !named_data)
goto new;
list_for_each_entry_rcu(test, &file->triggers, list) {
if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
if (!hist_trigger_match(data, test, named_data, false))
continue;
if (hist_data->attrs->pause)
test->paused = true;
else if (hist_data->attrs->cont)
test->paused = false;
else if (hist_data->attrs->clear)
hist_clear(test);
else
ret = -EEXIST;
goto out;
}
}
new:
if (hist_data->attrs->cont || hist_data->attrs->clear) {
ret = -ENOENT;
goto out;
}
if (hist_data->attrs->pause)
data->paused = true;
if (named_data) {
destroy_hist_data(data->private_data);
data->private_data = named_data->private_data;
set_named_trigger_data(data, named_data);
data->ops = &event_hist_trigger_named_ops;
}
if (data->ops->init) {
ret = data->ops->init(data->ops, data);
if (ret < 0)
goto out;
}
list_add_rcu(&data->list, &file->triggers);
ret++;
update_cond_flag(file);
if (trace_event_trigger_enable_disable(file, 1) < 0) {
list_del_rcu(&data->list);
update_cond_flag(file);
ret--;
}
out:
return ret;
}
static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops,
struct event_trigger_data *data,
struct trace_event_file *file)
{
struct hist_trigger_data *hist_data = data->private_data;
struct event_trigger_data *test, *named_data = NULL;
bool unregistered = false;
if (hist_data->attrs->name)
named_data = find_named_trigger(hist_data->attrs->name);
list_for_each_entry_rcu(test, &file->triggers, list) {
if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
if (!hist_trigger_match(data, test, named_data, false))
continue;
unregistered = true;
list_del_rcu(&test->list);
trace_event_trigger_enable_disable(file, 0);
update_cond_flag(file);
break;
}
}
if (unregistered && test->ops->free)
test->ops->free(test->ops, test);
}
static void hist_unreg_all(struct trace_event_file *file)
{
struct event_trigger_data *test, *n;
list_for_each_entry_safe(test, n, &file->triggers, list) {
if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
list_del_rcu(&test->list);
trace_event_trigger_enable_disable(file, 0);
update_cond_flag(file);
if (test->ops->free)
test->ops->free(test->ops, test);
}
}
}
static int event_hist_trigger_func(struct event_command *cmd_ops,
struct trace_event_file *file,
char *glob, char *cmd, char *param)
{
unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT;
struct event_trigger_data *trigger_data;
struct hist_trigger_attrs *attrs;
struct event_trigger_ops *trigger_ops;
struct hist_trigger_data *hist_data;
char *trigger;
int ret = 0;
if (!param)
return -EINVAL;
/* separate the trigger from the filter (k:v [if filter]) */
trigger = strsep(&param, " \t");
if (!trigger)
return -EINVAL;
attrs = parse_hist_trigger_attrs(trigger);
if (IS_ERR(attrs))
return PTR_ERR(attrs);
if (attrs->map_bits)
hist_trigger_bits = attrs->map_bits;
hist_data = create_hist_data(hist_trigger_bits, attrs, file);
if (IS_ERR(hist_data)) {
destroy_hist_trigger_attrs(attrs);
return PTR_ERR(hist_data);
}
trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger);
ret = -ENOMEM;
trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL);
if (!trigger_data)
goto out_free;
trigger_data->count = -1;
trigger_data->ops = trigger_ops;
trigger_data->cmd_ops = cmd_ops;
INIT_LIST_HEAD(&trigger_data->list);
RCU_INIT_POINTER(trigger_data->filter, NULL);
trigger_data->private_data = hist_data;
/* if param is non-empty, it's supposed to be a filter */
if (param && cmd_ops->set_filter) {
ret = cmd_ops->set_filter(param, trigger_data, file);
if (ret < 0)
goto out_free;
}
if (glob[0] == '!') {
cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file);
ret = 0;
goto out_free;
}
ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file);
/*
* The above returns on success the # of triggers registered,
* but if it didn't register any it returns zero. Consider no
* triggers registered a failure too.
*/
if (!ret) {
if (!(attrs->pause || attrs->cont || attrs->clear))
ret = -ENOENT;
goto out_free;
} else if (ret < 0)
goto out_free;
/* Just return zero, not the number of registered triggers */
ret = 0;
out:
return ret;
out_free:
if (cmd_ops->set_filter)
cmd_ops->set_filter(NULL, trigger_data, NULL);
kfree(trigger_data);
destroy_hist_data(hist_data);
goto out;
}
static struct event_command trigger_hist_cmd = {
.name = "hist",
.trigger_type = ETT_EVENT_HIST,
.flags = EVENT_CMD_FL_NEEDS_REC,
.func = event_hist_trigger_func,
.reg = hist_register_trigger,
.unreg = hist_unregister_trigger,
.unreg_all = hist_unreg_all,
.get_trigger_ops = event_hist_get_trigger_ops,
.set_filter = set_trigger_filter,
};
__init int register_trigger_hist_cmd(void)
{
int ret;
ret = register_event_command(&trigger_hist_cmd);
WARN_ON(ret < 0);
return ret;
}
static void
hist_enable_trigger(struct event_trigger_data *data, void *rec)
{
struct enable_trigger_data *enable_data = data->private_data;
struct event_trigger_data *test;
list_for_each_entry_rcu(test, &enable_data->file->triggers, list) {
if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
if (enable_data->enable)
test->paused = false;
else
test->paused = true;
}
}
}
static void
hist_enable_count_trigger(struct event_trigger_data *data, void *rec)
{
if (!data->count)
return;
if (data->count != -1)
(data->count)--;
hist_enable_trigger(data, rec);
}
static struct event_trigger_ops hist_enable_trigger_ops = {
.func = hist_enable_trigger,
.print = event_enable_trigger_print,
.init = event_trigger_init,
.free = event_enable_trigger_free,
};
static struct event_trigger_ops hist_enable_count_trigger_ops = {
.func = hist_enable_count_trigger,
.print = event_enable_trigger_print,
.init = event_trigger_init,
.free = event_enable_trigger_free,
};
static struct event_trigger_ops hist_disable_trigger_ops = {
.func = hist_enable_trigger,
.print = event_enable_trigger_print,
.init = event_trigger_init,
.free = event_enable_trigger_free,
};
static struct event_trigger_ops hist_disable_count_trigger_ops = {
.func = hist_enable_count_trigger,
.print = event_enable_trigger_print,
.init = event_trigger_init,
.free = event_enable_trigger_free,
};
static struct event_trigger_ops *
hist_enable_get_trigger_ops(char *cmd, char *param)
{
struct event_trigger_ops *ops;
bool enable;
enable = (strcmp(cmd, ENABLE_HIST_STR) == 0);
if (enable)
ops = param ? &hist_enable_count_trigger_ops :
&hist_enable_trigger_ops;
else
ops = param ? &hist_disable_count_trigger_ops :
&hist_disable_trigger_ops;
return ops;
}
static void hist_enable_unreg_all(struct trace_event_file *file)
{
struct event_trigger_data *test, *n;
list_for_each_entry_safe(test, n, &file->triggers, list) {
if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) {
list_del_rcu(&test->list);
update_cond_flag(file);
trace_event_trigger_enable_disable(file, 0);
if (test->ops->free)
test->ops->free(test->ops, test);
}
}
}
static struct event_command trigger_hist_enable_cmd = {
.name = ENABLE_HIST_STR,
.trigger_type = ETT_HIST_ENABLE,
.func = event_enable_trigger_func,
.reg = event_enable_register_trigger,
.unreg = event_enable_unregister_trigger,
.unreg_all = hist_enable_unreg_all,
.get_trigger_ops = hist_enable_get_trigger_ops,
.set_filter = set_trigger_filter,
};
static struct event_command trigger_hist_disable_cmd = {
.name = DISABLE_HIST_STR,
.trigger_type = ETT_HIST_ENABLE,
.func = event_enable_trigger_func,
.reg = event_enable_register_trigger,
.unreg = event_enable_unregister_trigger,
.unreg_all = hist_enable_unreg_all,
.get_trigger_ops = hist_enable_get_trigger_ops,
.set_filter = set_trigger_filter,
};
static __init void unregister_trigger_hist_enable_disable_cmds(void)
{
unregister_event_command(&trigger_hist_enable_cmd);
unregister_event_command(&trigger_hist_disable_cmd);
}
__init int register_trigger_hist_enable_disable_cmds(void)
{
int ret;
ret = register_event_command(&trigger_hist_enable_cmd);
if (WARN_ON(ret < 0))
return ret;
ret = register_event_command(&trigger_hist_disable_cmd);
if (WARN_ON(ret < 0))
unregister_trigger_hist_enable_disable_cmds();
return ret;
}