aboutsummaryrefslogtreecommitdiffstats
path: root/kernel/trace/trace_events_hist.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/trace/trace_events_hist.c')
-rw-r--r--kernel/trace/trace_events_hist.c1755
1 files changed, 1755 insertions, 0 deletions
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
new file mode 100644
index 000000000000..0c05b8a99806
--- /dev/null
+++ b/kernel/trace/trace_events_hist.c
@@ -0,0 +1,1755 @@
+/*
+ * 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 "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 (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 (hist_data->attrs->pause)
+ data->paused = true;
+
+ 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;
+
+ list_for_each_entry_rcu(test, &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;
+
+ list_for_each_entry_rcu(test, &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;
+}