v4.19.13 snapshot.
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
new file mode 100644
index 0000000..eb908ef
--- /dev/null
+++ b/kernel/trace/trace_events_hist.c
@@ -0,0 +1,5835 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * trace_events_hist - trace event hist triggers
+ *
+ * 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 <linux/tracefs.h>
+
+#include "tracing_map.h"
+#include "trace.h"
+
+#define SYNTH_SYSTEM "synthetic"
+#define SYNTH_FIELDS_MAX 16
+
+#define STR_VAR_LEN_MAX 32 /* must be multiple of sizeof(u64) */
+
+struct hist_field;
+
+typedef u64 (*hist_field_fn_t) (struct hist_field *field,
+ struct tracing_map_elt *elt,
+ struct ring_buffer_event *rbe,
+ void *event);
+
+#define HIST_FIELD_OPERANDS_MAX 2
+#define HIST_FIELDS_MAX (TRACING_MAP_FIELDS_MAX + TRACING_MAP_VARS_MAX)
+#define HIST_ACTIONS_MAX 8
+
+enum field_op_id {
+ FIELD_OP_NONE,
+ FIELD_OP_PLUS,
+ FIELD_OP_MINUS,
+ FIELD_OP_UNARY_MINUS,
+};
+
+struct hist_var {
+ char *name;
+ struct hist_trigger_data *hist_data;
+ unsigned int idx;
+};
+
+struct hist_field {
+ struct ftrace_event_field *field;
+ unsigned long flags;
+ hist_field_fn_t fn;
+ unsigned int size;
+ unsigned int offset;
+ unsigned int is_signed;
+ const char *type;
+ struct hist_field *operands[HIST_FIELD_OPERANDS_MAX];
+ struct hist_trigger_data *hist_data;
+ struct hist_var var;
+ enum field_op_id operator;
+ char *system;
+ char *event_name;
+ char *name;
+ unsigned int var_idx;
+ unsigned int var_ref_idx;
+ bool read_once;
+};
+
+static u64 hist_field_none(struct hist_field *field,
+ struct tracing_map_elt *elt,
+ struct ring_buffer_event *rbe,
+ void *event)
+{
+ return 0;
+}
+
+static u64 hist_field_counter(struct hist_field *field,
+ struct tracing_map_elt *elt,
+ struct ring_buffer_event *rbe,
+ void *event)
+{
+ return 1;
+}
+
+static u64 hist_field_string(struct hist_field *hist_field,
+ struct tracing_map_elt *elt,
+ struct ring_buffer_event *rbe,
+ 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,
+ struct tracing_map_elt *elt,
+ struct ring_buffer_event *rbe,
+ 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,
+ struct tracing_map_elt *elt,
+ struct ring_buffer_event *rbe,
+ 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,
+ struct tracing_map_elt *elt,
+ struct ring_buffer_event *rbe,
+ void *event)
+{
+ struct hist_field *operand = hist_field->operands[0];
+
+ u64 val = operand->fn(operand, elt, rbe, event);
+
+ return (u64) ilog2(roundup_pow_of_two(val));
+}
+
+static u64 hist_field_plus(struct hist_field *hist_field,
+ struct tracing_map_elt *elt,
+ struct ring_buffer_event *rbe,
+ void *event)
+{
+ struct hist_field *operand1 = hist_field->operands[0];
+ struct hist_field *operand2 = hist_field->operands[1];
+
+ u64 val1 = operand1->fn(operand1, elt, rbe, event);
+ u64 val2 = operand2->fn(operand2, elt, rbe, event);
+
+ return val1 + val2;
+}
+
+static u64 hist_field_minus(struct hist_field *hist_field,
+ struct tracing_map_elt *elt,
+ struct ring_buffer_event *rbe,
+ void *event)
+{
+ struct hist_field *operand1 = hist_field->operands[0];
+ struct hist_field *operand2 = hist_field->operands[1];
+
+ u64 val1 = operand1->fn(operand1, elt, rbe, event);
+ u64 val2 = operand2->fn(operand2, elt, rbe, event);
+
+ return val1 - val2;
+}
+
+static u64 hist_field_unary_minus(struct hist_field *hist_field,
+ struct tracing_map_elt *elt,
+ struct ring_buffer_event *rbe,
+ void *event)
+{
+ struct hist_field *operand = hist_field->operands[0];
+
+ s64 sval = (s64)operand->fn(operand, elt, rbe, event);
+ u64 val = (u64)-sval;
+
+ return val;
+}
+
+#define DEFINE_HIST_FIELD_FN(type) \
+ static u64 hist_field_##type(struct hist_field *hist_field, \
+ struct tracing_map_elt *elt, \
+ struct ring_buffer_event *rbe, \
+ 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 << 0,
+ HIST_FIELD_FL_KEY = 1 << 1,
+ HIST_FIELD_FL_STRING = 1 << 2,
+ HIST_FIELD_FL_HEX = 1 << 3,
+ HIST_FIELD_FL_SYM = 1 << 4,
+ HIST_FIELD_FL_SYM_OFFSET = 1 << 5,
+ HIST_FIELD_FL_EXECNAME = 1 << 6,
+ HIST_FIELD_FL_SYSCALL = 1 << 7,
+ HIST_FIELD_FL_STACKTRACE = 1 << 8,
+ HIST_FIELD_FL_LOG2 = 1 << 9,
+ HIST_FIELD_FL_TIMESTAMP = 1 << 10,
+ HIST_FIELD_FL_TIMESTAMP_USECS = 1 << 11,
+ HIST_FIELD_FL_VAR = 1 << 12,
+ HIST_FIELD_FL_EXPR = 1 << 13,
+ HIST_FIELD_FL_VAR_REF = 1 << 14,
+ HIST_FIELD_FL_CPU = 1 << 15,
+ HIST_FIELD_FL_ALIAS = 1 << 16,
+};
+
+struct var_defs {
+ unsigned int n_vars;
+ char *name[TRACING_MAP_VARS_MAX];
+ char *expr[TRACING_MAP_VARS_MAX];
+};
+
+struct hist_trigger_attrs {
+ char *keys_str;
+ char *vals_str;
+ char *sort_key_str;
+ char *name;
+ char *clock;
+ bool pause;
+ bool cont;
+ bool clear;
+ bool ts_in_usecs;
+ unsigned int map_bits;
+
+ char *assignment_str[TRACING_MAP_VARS_MAX];
+ unsigned int n_assignments;
+
+ char *action_str[HIST_ACTIONS_MAX];
+ unsigned int n_actions;
+
+ struct var_defs var_defs;
+};
+
+struct field_var {
+ struct hist_field *var;
+ struct hist_field *val;
+};
+
+struct field_var_hist {
+ struct hist_trigger_data *hist_data;
+ char *cmd;
+};
+
+struct hist_trigger_data {
+ struct hist_field *fields[HIST_FIELDS_MAX];
+ unsigned int n_vals;
+ unsigned int n_keys;
+ unsigned int n_fields;
+ unsigned int n_vars;
+ 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;
+ bool enable_timestamps;
+ bool remove;
+ struct hist_field *var_refs[TRACING_MAP_VARS_MAX];
+ unsigned int n_var_refs;
+
+ struct action_data *actions[HIST_ACTIONS_MAX];
+ unsigned int n_actions;
+
+ struct hist_field *synth_var_refs[SYNTH_FIELDS_MAX];
+ unsigned int n_synth_var_refs;
+ struct field_var *field_vars[SYNTH_FIELDS_MAX];
+ unsigned int n_field_vars;
+ unsigned int n_field_var_str;
+ struct field_var_hist *field_var_hists[SYNTH_FIELDS_MAX];
+ unsigned int n_field_var_hists;
+
+ struct field_var *max_vars[SYNTH_FIELDS_MAX];
+ unsigned int n_max_vars;
+ unsigned int n_max_var_str;
+};
+
+struct synth_field {
+ char *type;
+ char *name;
+ size_t size;
+ bool is_signed;
+ bool is_string;
+};
+
+struct synth_event {
+ struct list_head list;
+ int ref;
+ char *name;
+ struct synth_field **fields;
+ unsigned int n_fields;
+ unsigned int n_u64;
+ struct trace_event_class class;
+ struct trace_event_call call;
+ struct tracepoint *tp;
+};
+
+struct action_data;
+
+typedef void (*action_fn_t) (struct hist_trigger_data *hist_data,
+ struct tracing_map_elt *elt, void *rec,
+ struct ring_buffer_event *rbe,
+ struct action_data *data, u64 *var_ref_vals);
+
+struct action_data {
+ action_fn_t fn;
+ unsigned int n_params;
+ char *params[SYNTH_FIELDS_MAX];
+
+ union {
+ struct {
+ unsigned int var_ref_idx;
+ char *match_event;
+ char *match_event_system;
+ char *synth_event_name;
+ struct synth_event *synth_event;
+ } onmatch;
+
+ struct {
+ char *var_str;
+ char *fn_name;
+ unsigned int max_var_ref_idx;
+ struct hist_field *max_var;
+ struct hist_field *var;
+ } onmax;
+ };
+};
+
+
+static char last_hist_cmd[MAX_FILTER_STR_VAL];
+static char hist_err_str[MAX_FILTER_STR_VAL];
+
+static void last_cmd_set(char *str)
+{
+ if (!str)
+ return;
+
+ strncpy(last_hist_cmd, str, MAX_FILTER_STR_VAL - 1);
+}
+
+static void hist_err(char *str, char *var)
+{
+ int maxlen = MAX_FILTER_STR_VAL - 1;
+
+ if (!str)
+ return;
+
+ if (strlen(hist_err_str))
+ return;
+
+ if (!var)
+ var = "";
+
+ if (strlen(hist_err_str) + strlen(str) + strlen(var) > maxlen)
+ return;
+
+ strcat(hist_err_str, str);
+ strcat(hist_err_str, var);
+}
+
+static void hist_err_event(char *str, char *system, char *event, char *var)
+{
+ char err[MAX_FILTER_STR_VAL];
+
+ if (system && var)
+ snprintf(err, MAX_FILTER_STR_VAL, "%s.%s.%s", system, event, var);
+ else if (system)
+ snprintf(err, MAX_FILTER_STR_VAL, "%s.%s", system, event);
+ else
+ strscpy(err, var, MAX_FILTER_STR_VAL);
+
+ hist_err(str, err);
+}
+
+static void hist_err_clear(void)
+{
+ hist_err_str[0] = '\0';
+}
+
+static bool have_hist_err(void)
+{
+ if (strlen(hist_err_str))
+ return true;
+
+ return false;
+}
+
+static LIST_HEAD(synth_event_list);
+static DEFINE_MUTEX(synth_event_mutex);
+
+struct synth_trace_event {
+ struct trace_entry ent;
+ u64 fields[];
+};
+
+static int synth_event_define_fields(struct trace_event_call *call)
+{
+ struct synth_trace_event trace;
+ int offset = offsetof(typeof(trace), fields);
+ struct synth_event *event = call->data;
+ unsigned int i, size, n_u64;
+ char *name, *type;
+ bool is_signed;
+ int ret = 0;
+
+ for (i = 0, n_u64 = 0; i < event->n_fields; i++) {
+ size = event->fields[i]->size;
+ is_signed = event->fields[i]->is_signed;
+ type = event->fields[i]->type;
+ name = event->fields[i]->name;
+ ret = trace_define_field(call, type, name, offset, size,
+ is_signed, FILTER_OTHER);
+ if (ret)
+ break;
+
+ if (event->fields[i]->is_string) {
+ offset += STR_VAR_LEN_MAX;
+ n_u64 += STR_VAR_LEN_MAX / sizeof(u64);
+ } else {
+ offset += sizeof(u64);
+ n_u64++;
+ }
+ }
+
+ event->n_u64 = n_u64;
+
+ return ret;
+}
+
+static bool synth_field_signed(char *type)
+{
+ if (strncmp(type, "u", 1) == 0)
+ return false;
+
+ return true;
+}
+
+static int synth_field_is_string(char *type)
+{
+ if (strstr(type, "char[") != NULL)
+ return true;
+
+ return false;
+}
+
+static int synth_field_string_size(char *type)
+{
+ char buf[4], *end, *start;
+ unsigned int len;
+ int size, err;
+
+ start = strstr(type, "char[");
+ if (start == NULL)
+ return -EINVAL;
+ start += strlen("char[");
+
+ end = strchr(type, ']');
+ if (!end || end < start)
+ return -EINVAL;
+
+ len = end - start;
+ if (len > 3)
+ return -EINVAL;
+
+ strncpy(buf, start, len);
+ buf[len] = '\0';
+
+ err = kstrtouint(buf, 0, &size);
+ if (err)
+ return err;
+
+ if (size > STR_VAR_LEN_MAX)
+ return -EINVAL;
+
+ return size;
+}
+
+static int synth_field_size(char *type)
+{
+ int size = 0;
+
+ if (strcmp(type, "s64") == 0)
+ size = sizeof(s64);
+ else if (strcmp(type, "u64") == 0)
+ size = sizeof(u64);
+ else if (strcmp(type, "s32") == 0)
+ size = sizeof(s32);
+ else if (strcmp(type, "u32") == 0)
+ size = sizeof(u32);
+ else if (strcmp(type, "s16") == 0)
+ size = sizeof(s16);
+ else if (strcmp(type, "u16") == 0)
+ size = sizeof(u16);
+ else if (strcmp(type, "s8") == 0)
+ size = sizeof(s8);
+ else if (strcmp(type, "u8") == 0)
+ size = sizeof(u8);
+ else if (strcmp(type, "char") == 0)
+ size = sizeof(char);
+ else if (strcmp(type, "unsigned char") == 0)
+ size = sizeof(unsigned char);
+ else if (strcmp(type, "int") == 0)
+ size = sizeof(int);
+ else if (strcmp(type, "unsigned int") == 0)
+ size = sizeof(unsigned int);
+ else if (strcmp(type, "long") == 0)
+ size = sizeof(long);
+ else if (strcmp(type, "unsigned long") == 0)
+ size = sizeof(unsigned long);
+ else if (strcmp(type, "pid_t") == 0)
+ size = sizeof(pid_t);
+ else if (synth_field_is_string(type))
+ size = synth_field_string_size(type);
+
+ return size;
+}
+
+static const char *synth_field_fmt(char *type)
+{
+ const char *fmt = "%llu";
+
+ if (strcmp(type, "s64") == 0)
+ fmt = "%lld";
+ else if (strcmp(type, "u64") == 0)
+ fmt = "%llu";
+ else if (strcmp(type, "s32") == 0)
+ fmt = "%d";
+ else if (strcmp(type, "u32") == 0)
+ fmt = "%u";
+ else if (strcmp(type, "s16") == 0)
+ fmt = "%d";
+ else if (strcmp(type, "u16") == 0)
+ fmt = "%u";
+ else if (strcmp(type, "s8") == 0)
+ fmt = "%d";
+ else if (strcmp(type, "u8") == 0)
+ fmt = "%u";
+ else if (strcmp(type, "char") == 0)
+ fmt = "%d";
+ else if (strcmp(type, "unsigned char") == 0)
+ fmt = "%u";
+ else if (strcmp(type, "int") == 0)
+ fmt = "%d";
+ else if (strcmp(type, "unsigned int") == 0)
+ fmt = "%u";
+ else if (strcmp(type, "long") == 0)
+ fmt = "%ld";
+ else if (strcmp(type, "unsigned long") == 0)
+ fmt = "%lu";
+ else if (strcmp(type, "pid_t") == 0)
+ fmt = "%d";
+ else if (synth_field_is_string(type))
+ fmt = "%s";
+
+ return fmt;
+}
+
+static enum print_line_t print_synth_event(struct trace_iterator *iter,
+ int flags,
+ struct trace_event *event)
+{
+ struct trace_array *tr = iter->tr;
+ struct trace_seq *s = &iter->seq;
+ struct synth_trace_event *entry;
+ struct synth_event *se;
+ unsigned int i, n_u64;
+ char print_fmt[32];
+ const char *fmt;
+
+ entry = (struct synth_trace_event *)iter->ent;
+ se = container_of(event, struct synth_event, call.event);
+
+ trace_seq_printf(s, "%s: ", se->name);
+
+ for (i = 0, n_u64 = 0; i < se->n_fields; i++) {
+ if (trace_seq_has_overflowed(s))
+ goto end;
+
+ fmt = synth_field_fmt(se->fields[i]->type);
+
+ /* parameter types */
+ if (tr->trace_flags & TRACE_ITER_VERBOSE)
+ trace_seq_printf(s, "%s ", fmt);
+
+ snprintf(print_fmt, sizeof(print_fmt), "%%s=%s%%s", fmt);
+
+ /* parameter values */
+ if (se->fields[i]->is_string) {
+ trace_seq_printf(s, print_fmt, se->fields[i]->name,
+ (char *)&entry->fields[n_u64],
+ i == se->n_fields - 1 ? "" : " ");
+ n_u64 += STR_VAR_LEN_MAX / sizeof(u64);
+ } else {
+ trace_seq_printf(s, print_fmt, se->fields[i]->name,
+ entry->fields[n_u64],
+ i == se->n_fields - 1 ? "" : " ");
+ n_u64++;
+ }
+ }
+end:
+ trace_seq_putc(s, '\n');
+
+ return trace_handle_return(s);
+}
+
+static struct trace_event_functions synth_event_funcs = {
+ .trace = print_synth_event
+};
+
+static notrace void trace_event_raw_event_synth(void *__data,
+ u64 *var_ref_vals,
+ unsigned int var_ref_idx)
+{
+ struct trace_event_file *trace_file = __data;
+ struct synth_trace_event *entry;
+ struct trace_event_buffer fbuffer;
+ struct ring_buffer *buffer;
+ struct synth_event *event;
+ unsigned int i, n_u64;
+ int fields_size = 0;
+
+ event = trace_file->event_call->data;
+
+ if (trace_trigger_soft_disabled(trace_file))
+ return;
+
+ fields_size = event->n_u64 * sizeof(u64);
+
+ /*
+ * Avoid ring buffer recursion detection, as this event
+ * is being performed within another event.
+ */
+ buffer = trace_file->tr->trace_buffer.buffer;
+ ring_buffer_nest_start(buffer);
+
+ entry = trace_event_buffer_reserve(&fbuffer, trace_file,
+ sizeof(*entry) + fields_size);
+ if (!entry)
+ goto out;
+
+ for (i = 0, n_u64 = 0; i < event->n_fields; i++) {
+ if (event->fields[i]->is_string) {
+ char *str_val = (char *)(long)var_ref_vals[var_ref_idx + i];
+ char *str_field = (char *)&entry->fields[n_u64];
+
+ strscpy(str_field, str_val, STR_VAR_LEN_MAX);
+ n_u64 += STR_VAR_LEN_MAX / sizeof(u64);
+ } else {
+ entry->fields[n_u64] = var_ref_vals[var_ref_idx + i];
+ n_u64++;
+ }
+ }
+
+ trace_event_buffer_commit(&fbuffer);
+out:
+ ring_buffer_nest_end(buffer);
+}
+
+static void free_synth_event_print_fmt(struct trace_event_call *call)
+{
+ if (call) {
+ kfree(call->print_fmt);
+ call->print_fmt = NULL;
+ }
+}
+
+static int __set_synth_event_print_fmt(struct synth_event *event,
+ char *buf, int len)
+{
+ const char *fmt;
+ int pos = 0;
+ int i;
+
+ /* When len=0, we just calculate the needed length */
+#define LEN_OR_ZERO (len ? len - pos : 0)
+
+ pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
+ for (i = 0; i < event->n_fields; i++) {
+ fmt = synth_field_fmt(event->fields[i]->type);
+ pos += snprintf(buf + pos, LEN_OR_ZERO, "%s=%s%s",
+ event->fields[i]->name, fmt,
+ i == event->n_fields - 1 ? "" : ", ");
+ }
+ pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
+
+ for (i = 0; i < event->n_fields; i++) {
+ pos += snprintf(buf + pos, LEN_OR_ZERO,
+ ", REC->%s", event->fields[i]->name);
+ }
+
+#undef LEN_OR_ZERO
+
+ /* return the length of print_fmt */
+ return pos;
+}
+
+static int set_synth_event_print_fmt(struct trace_event_call *call)
+{
+ struct synth_event *event = call->data;
+ char *print_fmt;
+ int len;
+
+ /* First: called with 0 length to calculate the needed length */
+ len = __set_synth_event_print_fmt(event, NULL, 0);
+
+ print_fmt = kmalloc(len + 1, GFP_KERNEL);
+ if (!print_fmt)
+ return -ENOMEM;
+
+ /* Second: actually write the @print_fmt */
+ __set_synth_event_print_fmt(event, print_fmt, len + 1);
+ call->print_fmt = print_fmt;
+
+ return 0;
+}
+
+static void free_synth_field(struct synth_field *field)
+{
+ kfree(field->type);
+ kfree(field->name);
+ kfree(field);
+}
+
+static struct synth_field *parse_synth_field(int argc, char **argv,
+ int *consumed)
+{
+ struct synth_field *field;
+ const char *prefix = NULL;
+ char *field_type = argv[0], *field_name;
+ int len, ret = 0;
+ char *array;
+
+ if (field_type[0] == ';')
+ field_type++;
+
+ if (!strcmp(field_type, "unsigned")) {
+ if (argc < 3)
+ return ERR_PTR(-EINVAL);
+ prefix = "unsigned ";
+ field_type = argv[1];
+ field_name = argv[2];
+ *consumed = 3;
+ } else {
+ field_name = argv[1];
+ *consumed = 2;
+ }
+
+ len = strlen(field_name);
+ if (field_name[len - 1] == ';')
+ field_name[len - 1] = '\0';
+
+ field = kzalloc(sizeof(*field), GFP_KERNEL);
+ if (!field)
+ return ERR_PTR(-ENOMEM);
+
+ len = strlen(field_type) + 1;
+ array = strchr(field_name, '[');
+ if (array)
+ len += strlen(array);
+ if (prefix)
+ len += strlen(prefix);
+ field->type = kzalloc(len, GFP_KERNEL);
+ if (!field->type) {
+ ret = -ENOMEM;
+ goto free;
+ }
+ if (prefix)
+ strcat(field->type, prefix);
+ strcat(field->type, field_type);
+ if (array) {
+ strcat(field->type, array);
+ *array = '\0';
+ }
+
+ field->size = synth_field_size(field->type);
+ if (!field->size) {
+ ret = -EINVAL;
+ goto free;
+ }
+
+ if (synth_field_is_string(field->type))
+ field->is_string = true;
+
+ field->is_signed = synth_field_signed(field->type);
+
+ field->name = kstrdup(field_name, GFP_KERNEL);
+ if (!field->name) {
+ ret = -ENOMEM;
+ goto free;
+ }
+ out:
+ return field;
+ free:
+ free_synth_field(field);
+ field = ERR_PTR(ret);
+ goto out;
+}
+
+static void free_synth_tracepoint(struct tracepoint *tp)
+{
+ if (!tp)
+ return;
+
+ kfree(tp->name);
+ kfree(tp);
+}
+
+static struct tracepoint *alloc_synth_tracepoint(char *name)
+{
+ struct tracepoint *tp;
+
+ tp = kzalloc(sizeof(*tp), GFP_KERNEL);
+ if (!tp)
+ return ERR_PTR(-ENOMEM);
+
+ tp->name = kstrdup(name, GFP_KERNEL);
+ if (!tp->name) {
+ kfree(tp);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ return tp;
+}
+
+typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals,
+ unsigned int var_ref_idx);
+
+static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals,
+ unsigned int var_ref_idx)
+{
+ struct tracepoint *tp = event->tp;
+
+ if (unlikely(atomic_read(&tp->key.enabled) > 0)) {
+ struct tracepoint_func *probe_func_ptr;
+ synth_probe_func_t probe_func;
+ void *__data;
+
+ if (!(cpu_online(raw_smp_processor_id())))
+ return;
+
+ probe_func_ptr = rcu_dereference_sched((tp)->funcs);
+ if (probe_func_ptr) {
+ do {
+ probe_func = probe_func_ptr->func;
+ __data = probe_func_ptr->data;
+ probe_func(__data, var_ref_vals, var_ref_idx);
+ } while ((++probe_func_ptr)->func);
+ }
+ }
+}
+
+static struct synth_event *find_synth_event(const char *name)
+{
+ struct synth_event *event;
+
+ list_for_each_entry(event, &synth_event_list, list) {
+ if (strcmp(event->name, name) == 0)
+ return event;
+ }
+
+ return NULL;
+}
+
+static int register_synth_event(struct synth_event *event)
+{
+ struct trace_event_call *call = &event->call;
+ int ret = 0;
+
+ event->call.class = &event->class;
+ event->class.system = kstrdup(SYNTH_SYSTEM, GFP_KERNEL);
+ if (!event->class.system) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ event->tp = alloc_synth_tracepoint(event->name);
+ if (IS_ERR(event->tp)) {
+ ret = PTR_ERR(event->tp);
+ event->tp = NULL;
+ goto out;
+ }
+
+ INIT_LIST_HEAD(&call->class->fields);
+ call->event.funcs = &synth_event_funcs;
+ call->class->define_fields = synth_event_define_fields;
+
+ ret = register_trace_event(&call->event);
+ if (!ret) {
+ ret = -ENODEV;
+ goto out;
+ }
+ call->flags = TRACE_EVENT_FL_TRACEPOINT;
+ call->class->reg = trace_event_reg;
+ call->class->probe = trace_event_raw_event_synth;
+ call->data = event;
+ call->tp = event->tp;
+
+ ret = trace_add_event_call(call);
+ if (ret) {
+ pr_warn("Failed to register synthetic event: %s\n",
+ trace_event_name(call));
+ goto err;
+ }
+
+ ret = set_synth_event_print_fmt(call);
+ if (ret < 0) {
+ trace_remove_event_call(call);
+ goto err;
+ }
+ out:
+ return ret;
+ err:
+ unregister_trace_event(&call->event);
+ goto out;
+}
+
+static int unregister_synth_event(struct synth_event *event)
+{
+ struct trace_event_call *call = &event->call;
+ int ret;
+
+ ret = trace_remove_event_call(call);
+
+ return ret;
+}
+
+static void free_synth_event(struct synth_event *event)
+{
+ unsigned int i;
+
+ if (!event)
+ return;
+
+ for (i = 0; i < event->n_fields; i++)
+ free_synth_field(event->fields[i]);
+
+ kfree(event->fields);
+ kfree(event->name);
+ kfree(event->class.system);
+ free_synth_tracepoint(event->tp);
+ free_synth_event_print_fmt(&event->call);
+ kfree(event);
+}
+
+static struct synth_event *alloc_synth_event(char *event_name, int n_fields,
+ struct synth_field **fields)
+{
+ struct synth_event *event;
+ unsigned int i;
+
+ event = kzalloc(sizeof(*event), GFP_KERNEL);
+ if (!event) {
+ event = ERR_PTR(-ENOMEM);
+ goto out;
+ }
+
+ event->name = kstrdup(event_name, GFP_KERNEL);
+ if (!event->name) {
+ kfree(event);
+ event = ERR_PTR(-ENOMEM);
+ goto out;
+ }
+
+ event->fields = kcalloc(n_fields, sizeof(*event->fields), GFP_KERNEL);
+ if (!event->fields) {
+ free_synth_event(event);
+ event = ERR_PTR(-ENOMEM);
+ goto out;
+ }
+
+ for (i = 0; i < n_fields; i++)
+ event->fields[i] = fields[i];
+
+ event->n_fields = n_fields;
+ out:
+ return event;
+}
+
+static void action_trace(struct hist_trigger_data *hist_data,
+ struct tracing_map_elt *elt, void *rec,
+ struct ring_buffer_event *rbe,
+ struct action_data *data, u64 *var_ref_vals)
+{
+ struct synth_event *event = data->onmatch.synth_event;
+
+ trace_synth(event, var_ref_vals, data->onmatch.var_ref_idx);
+}
+
+struct hist_var_data {
+ struct list_head list;
+ struct hist_trigger_data *hist_data;
+};
+
+static void add_or_delete_synth_event(struct synth_event *event, int delete)
+{
+ if (delete)
+ free_synth_event(event);
+ else {
+ mutex_lock(&synth_event_mutex);
+ if (!find_synth_event(event->name))
+ list_add(&event->list, &synth_event_list);
+ else
+ free_synth_event(event);
+ mutex_unlock(&synth_event_mutex);
+ }
+}
+
+static int create_synth_event(int argc, char **argv)
+{
+ struct synth_field *field, *fields[SYNTH_FIELDS_MAX];
+ struct synth_event *event = NULL;
+ bool delete_event = false;
+ int i, consumed = 0, n_fields = 0, ret = 0;
+ char *name;
+
+ mutex_lock(&synth_event_mutex);
+
+ /*
+ * Argument syntax:
+ * - Add synthetic event: <event_name> field[;field] ...
+ * - Remove synthetic event: !<event_name> field[;field] ...
+ * where 'field' = type field_name
+ */
+ if (argc < 1) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ name = argv[0];
+ if (name[0] == '!') {
+ delete_event = true;
+ name++;
+ }
+
+ event = find_synth_event(name);
+ if (event) {
+ if (delete_event) {
+ if (event->ref) {
+ event = NULL;
+ ret = -EBUSY;
+ goto out;
+ }
+ list_del(&event->list);
+ goto out;
+ }
+ event = NULL;
+ ret = -EEXIST;
+ goto out;
+ } else if (delete_event) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+ if (argc < 2) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ for (i = 1; i < argc - 1; i++) {
+ if (strcmp(argv[i], ";") == 0)
+ continue;
+ if (n_fields == SYNTH_FIELDS_MAX) {
+ ret = -EINVAL;
+ goto err;
+ }
+
+ field = parse_synth_field(argc - i, &argv[i], &consumed);
+ if (IS_ERR(field)) {
+ ret = PTR_ERR(field);
+ goto err;
+ }
+ fields[n_fields++] = field;
+ i += consumed - 1;
+ }
+
+ if (i < argc && strcmp(argv[i], ";") != 0) {
+ ret = -EINVAL;
+ goto err;
+ }
+
+ event = alloc_synth_event(name, n_fields, fields);
+ if (IS_ERR(event)) {
+ ret = PTR_ERR(event);
+ event = NULL;
+ goto err;
+ }
+ out:
+ mutex_unlock(&synth_event_mutex);
+
+ if (event) {
+ if (delete_event) {
+ ret = unregister_synth_event(event);
+ add_or_delete_synth_event(event, !ret);
+ } else {
+ ret = register_synth_event(event);
+ add_or_delete_synth_event(event, ret);
+ }
+ }
+
+ return ret;
+ err:
+ mutex_unlock(&synth_event_mutex);
+
+ for (i = 0; i < n_fields; i++)
+ free_synth_field(fields[i]);
+ free_synth_event(event);
+
+ return ret;
+}
+
+static int release_all_synth_events(void)
+{
+ struct list_head release_events;
+ struct synth_event *event, *e;
+ int ret = 0;
+
+ INIT_LIST_HEAD(&release_events);
+
+ mutex_lock(&synth_event_mutex);
+
+ list_for_each_entry(event, &synth_event_list, list) {
+ if (event->ref) {
+ mutex_unlock(&synth_event_mutex);
+ return -EBUSY;
+ }
+ }
+
+ list_splice_init(&event->list, &release_events);
+
+ mutex_unlock(&synth_event_mutex);
+
+ list_for_each_entry_safe(event, e, &release_events, list) {
+ list_del(&event->list);
+
+ ret = unregister_synth_event(event);
+ add_or_delete_synth_event(event, !ret);
+ }
+
+ return ret;
+}
+
+
+static void *synth_events_seq_start(struct seq_file *m, loff_t *pos)
+{
+ mutex_lock(&synth_event_mutex);
+
+ return seq_list_start(&synth_event_list, *pos);
+}
+
+static void *synth_events_seq_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ return seq_list_next(v, &synth_event_list, pos);
+}
+
+static void synth_events_seq_stop(struct seq_file *m, void *v)
+{
+ mutex_unlock(&synth_event_mutex);
+}
+
+static int synth_events_seq_show(struct seq_file *m, void *v)
+{
+ struct synth_field *field;
+ struct synth_event *event = v;
+ unsigned int i;
+
+ seq_printf(m, "%s\t", event->name);
+
+ for (i = 0; i < event->n_fields; i++) {
+ field = event->fields[i];
+
+ /* parameter values */
+ seq_printf(m, "%s %s%s", field->type, field->name,
+ i == event->n_fields - 1 ? "" : "; ");
+ }
+
+ seq_putc(m, '\n');
+
+ return 0;
+}
+
+static const struct seq_operations synth_events_seq_op = {
+ .start = synth_events_seq_start,
+ .next = synth_events_seq_next,
+ .stop = synth_events_seq_stop,
+ .show = synth_events_seq_show
+};
+
+static int synth_events_open(struct inode *inode, struct file *file)
+{
+ int ret;
+
+ if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
+ ret = release_all_synth_events();
+ if (ret < 0)
+ return ret;
+ }
+
+ return seq_open(file, &synth_events_seq_op);
+}
+
+static ssize_t synth_events_write(struct file *file,
+ const char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ return trace_parse_run_command(file, buffer, count, ppos,
+ create_synth_event);
+}
+
+static const struct file_operations synth_events_fops = {
+ .open = synth_events_open,
+ .write = synth_events_write,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static u64 hist_field_timestamp(struct hist_field *hist_field,
+ struct tracing_map_elt *elt,
+ struct ring_buffer_event *rbe,
+ void *event)
+{
+ struct hist_trigger_data *hist_data = hist_field->hist_data;
+ struct trace_array *tr = hist_data->event_file->tr;
+
+ u64 ts = ring_buffer_event_time_stamp(rbe);
+
+ if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr))
+ ts = ns2usecs(ts);
+
+ return ts;
+}
+
+static u64 hist_field_cpu(struct hist_field *hist_field,
+ struct tracing_map_elt *elt,
+ struct ring_buffer_event *rbe,
+ void *event)
+{
+ int cpu = smp_processor_id();
+
+ return cpu;
+}
+
+static struct hist_field *
+check_field_for_var_ref(struct hist_field *hist_field,
+ struct hist_trigger_data *var_data,
+ unsigned int var_idx)
+{
+ struct hist_field *found = NULL;
+
+ if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF) {
+ if (hist_field->var.idx == var_idx &&
+ hist_field->var.hist_data == var_data) {
+ found = hist_field;
+ }
+ }
+
+ return found;
+}
+
+static struct hist_field *
+check_field_for_var_refs(struct hist_trigger_data *hist_data,
+ struct hist_field *hist_field,
+ struct hist_trigger_data *var_data,
+ unsigned int var_idx,
+ unsigned int level)
+{
+ struct hist_field *found = NULL;
+ unsigned int i;
+
+ if (level > 3)
+ return found;
+
+ if (!hist_field)
+ return found;
+
+ found = check_field_for_var_ref(hist_field, var_data, var_idx);
+ if (found)
+ return found;
+
+ for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) {
+ struct hist_field *operand;
+
+ operand = hist_field->operands[i];
+ found = check_field_for_var_refs(hist_data, operand, var_data,
+ var_idx, level + 1);
+ if (found)
+ return found;
+ }
+
+ return found;
+}
+
+static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data,
+ struct hist_trigger_data *var_data,
+ unsigned int var_idx)
+{
+ struct hist_field *hist_field, *found = NULL;
+ unsigned int i;
+
+ for_each_hist_field(i, hist_data) {
+ hist_field = hist_data->fields[i];
+ found = check_field_for_var_refs(hist_data, hist_field,
+ var_data, var_idx, 0);
+ if (found)
+ return found;
+ }
+
+ for (i = 0; i < hist_data->n_synth_var_refs; i++) {
+ hist_field = hist_data->synth_var_refs[i];
+ found = check_field_for_var_refs(hist_data, hist_field,
+ var_data, var_idx, 0);
+ if (found)
+ return found;
+ }
+
+ return found;
+}
+
+static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data,
+ unsigned int var_idx)
+{
+ struct trace_array *tr = hist_data->event_file->tr;
+ struct hist_field *found = NULL;
+ struct hist_var_data *var_data;
+
+ list_for_each_entry(var_data, &tr->hist_vars, list) {
+ if (var_data->hist_data == hist_data)
+ continue;
+ found = find_var_ref(var_data->hist_data, hist_data, var_idx);
+ if (found)
+ break;
+ }
+
+ return found;
+}
+
+static bool check_var_refs(struct hist_trigger_data *hist_data)
+{
+ struct hist_field *field;
+ bool found = false;
+ int i;
+
+ for_each_hist_field(i, hist_data) {
+ field = hist_data->fields[i];
+ if (field && field->flags & HIST_FIELD_FL_VAR) {
+ if (find_any_var_ref(hist_data, field->var.idx)) {
+ found = true;
+ break;
+ }
+ }
+ }
+
+ return found;
+}
+
+static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data)
+{
+ struct trace_array *tr = hist_data->event_file->tr;
+ struct hist_var_data *var_data, *found = NULL;
+
+ list_for_each_entry(var_data, &tr->hist_vars, list) {
+ if (var_data->hist_data == hist_data) {
+ found = var_data;
+ break;
+ }
+ }
+
+ return found;
+}
+
+static bool field_has_hist_vars(struct hist_field *hist_field,
+ unsigned int level)
+{
+ int i;
+
+ if (level > 3)
+ return false;
+
+ if (!hist_field)
+ return false;
+
+ if (hist_field->flags & HIST_FIELD_FL_VAR ||
+ hist_field->flags & HIST_FIELD_FL_VAR_REF)
+ return true;
+
+ for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) {
+ struct hist_field *operand;
+
+ operand = hist_field->operands[i];
+ if (field_has_hist_vars(operand, level + 1))
+ return true;
+ }
+
+ return false;
+}
+
+static bool has_hist_vars(struct hist_trigger_data *hist_data)
+{
+ struct hist_field *hist_field;
+ int i;
+
+ for_each_hist_field(i, hist_data) {
+ hist_field = hist_data->fields[i];
+ if (field_has_hist_vars(hist_field, 0))
+ return true;
+ }
+
+ return false;
+}
+
+static int save_hist_vars(struct hist_trigger_data *hist_data)
+{
+ struct trace_array *tr = hist_data->event_file->tr;
+ struct hist_var_data *var_data;
+
+ var_data = find_hist_vars(hist_data);
+ if (var_data)
+ return 0;
+
+ if (trace_array_get(tr) < 0)
+ return -ENODEV;
+
+ var_data = kzalloc(sizeof(*var_data), GFP_KERNEL);
+ if (!var_data) {
+ trace_array_put(tr);
+ return -ENOMEM;
+ }
+
+ var_data->hist_data = hist_data;
+ list_add(&var_data->list, &tr->hist_vars);
+
+ return 0;
+}
+
+static void remove_hist_vars(struct hist_trigger_data *hist_data)
+{
+ struct trace_array *tr = hist_data->event_file->tr;
+ struct hist_var_data *var_data;
+
+ var_data = find_hist_vars(hist_data);
+ if (!var_data)
+ return;
+
+ if (WARN_ON(check_var_refs(hist_data)))
+ return;
+
+ list_del(&var_data->list);
+
+ kfree(var_data);
+
+ trace_array_put(tr);
+}
+
+static struct hist_field *find_var_field(struct hist_trigger_data *hist_data,
+ const char *var_name)
+{
+ struct hist_field *hist_field, *found = NULL;
+ int i;
+
+ for_each_hist_field(i, hist_data) {
+ hist_field = hist_data->fields[i];
+ if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR &&
+ strcmp(hist_field->var.name, var_name) == 0) {
+ found = hist_field;
+ break;
+ }
+ }
+
+ return found;
+}
+
+static struct hist_field *find_var(struct hist_trigger_data *hist_data,
+ struct trace_event_file *file,
+ const char *var_name)
+{
+ struct hist_trigger_data *test_data;
+ struct event_trigger_data *test;
+ struct hist_field *hist_field;
+
+ hist_field = find_var_field(hist_data, var_name);
+ if (hist_field)
+ return hist_field;
+
+ list_for_each_entry_rcu(test, &file->triggers, list) {
+ if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
+ test_data = test->private_data;
+ hist_field = find_var_field(test_data, var_name);
+ if (hist_field)
+ return hist_field;
+ }
+ }
+
+ return NULL;
+}
+
+static struct trace_event_file *find_var_file(struct trace_array *tr,
+ char *system,
+ char *event_name,
+ char *var_name)
+{
+ struct hist_trigger_data *var_hist_data;
+ struct hist_var_data *var_data;
+ struct trace_event_file *file, *found = NULL;
+
+ if (system)
+ return find_event_file(tr, system, event_name);
+
+ list_for_each_entry(var_data, &tr->hist_vars, list) {
+ var_hist_data = var_data->hist_data;
+ file = var_hist_data->event_file;
+ if (file == found)
+ continue;
+
+ if (find_var_field(var_hist_data, var_name)) {
+ if (found) {
+ hist_err_event("Variable name not unique, need to use fully qualified name (subsys.event.var) for variable: ", system, event_name, var_name);
+ return NULL;
+ }
+
+ found = file;
+ }
+ }
+
+ return found;
+}
+
+static struct hist_field *find_file_var(struct trace_event_file *file,
+ const char *var_name)
+{
+ struct hist_trigger_data *test_data;
+ struct event_trigger_data *test;
+ struct hist_field *hist_field;
+
+ list_for_each_entry_rcu(test, &file->triggers, list) {
+ if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
+ test_data = test->private_data;
+ hist_field = find_var_field(test_data, var_name);
+ if (hist_field)
+ return hist_field;
+ }
+ }
+
+ return NULL;
+}
+
+static struct hist_field *
+find_match_var(struct hist_trigger_data *hist_data, char *var_name)
+{
+ struct trace_array *tr = hist_data->event_file->tr;
+ struct hist_field *hist_field, *found = NULL;
+ struct trace_event_file *file;
+ unsigned int i;
+
+ for (i = 0; i < hist_data->n_actions; i++) {
+ struct action_data *data = hist_data->actions[i];
+
+ if (data->fn == action_trace) {
+ char *system = data->onmatch.match_event_system;
+ char *event_name = data->onmatch.match_event;
+
+ file = find_var_file(tr, system, event_name, var_name);
+ if (!file)
+ continue;
+ hist_field = find_file_var(file, var_name);
+ if (hist_field) {
+ if (found) {
+ hist_err_event("Variable name not unique, need to use fully qualified name (subsys.event.var) for variable: ", system, event_name, var_name);
+ return ERR_PTR(-EINVAL);
+ }
+
+ found = hist_field;
+ }
+ }
+ }
+ return found;
+}
+
+static struct hist_field *find_event_var(struct hist_trigger_data *hist_data,
+ char *system,
+ char *event_name,
+ char *var_name)
+{
+ struct trace_array *tr = hist_data->event_file->tr;
+ struct hist_field *hist_field = NULL;
+ struct trace_event_file *file;
+
+ if (!system || !event_name) {
+ hist_field = find_match_var(hist_data, var_name);
+ if (IS_ERR(hist_field))
+ return NULL;
+ if (hist_field)
+ return hist_field;
+ }
+
+ file = find_var_file(tr, system, event_name, var_name);
+ if (!file)
+ return NULL;
+
+ hist_field = find_file_var(file, var_name);
+
+ return hist_field;
+}
+
+struct hist_elt_data {
+ char *comm;
+ u64 *var_ref_vals;
+ char *field_var_str[SYNTH_FIELDS_MAX];
+};
+
+static u64 hist_field_var_ref(struct hist_field *hist_field,
+ struct tracing_map_elt *elt,
+ struct ring_buffer_event *rbe,
+ void *event)
+{
+ struct hist_elt_data *elt_data;
+ u64 var_val = 0;
+
+ elt_data = elt->private_data;
+ var_val = elt_data->var_ref_vals[hist_field->var_ref_idx];
+
+ return var_val;
+}
+
+static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key,
+ u64 *var_ref_vals, bool self)
+{
+ struct hist_trigger_data *var_data;
+ struct tracing_map_elt *var_elt;
+ struct hist_field *hist_field;
+ unsigned int i, var_idx;
+ bool resolved = true;
+ u64 var_val = 0;
+
+ for (i = 0; i < hist_data->n_var_refs; i++) {
+ hist_field = hist_data->var_refs[i];
+ var_idx = hist_field->var.idx;
+ var_data = hist_field->var.hist_data;
+
+ if (var_data == NULL) {
+ resolved = false;
+ break;
+ }
+
+ if ((self && var_data != hist_data) ||
+ (!self && var_data == hist_data))
+ continue;
+
+ var_elt = tracing_map_lookup(var_data->map, key);
+ if (!var_elt) {
+ resolved = false;
+ break;
+ }
+
+ if (!tracing_map_var_set(var_elt, var_idx)) {
+ resolved = false;
+ break;
+ }
+
+ if (self || !hist_field->read_once)
+ var_val = tracing_map_read_var(var_elt, var_idx);
+ else
+ var_val = tracing_map_read_var_once(var_elt, var_idx);
+
+ var_ref_vals[i] = var_val;
+ }
+
+ return resolved;
+}
+
+static const char *hist_field_name(struct hist_field *field,
+ unsigned int level)
+{
+ const char *field_name = "";
+
+ if (level > 1)
+ return field_name;
+
+ if (field->field)
+ field_name = field->field->name;
+ else if (field->flags & HIST_FIELD_FL_LOG2 ||
+ field->flags & HIST_FIELD_FL_ALIAS)
+ field_name = hist_field_name(field->operands[0], ++level);
+ else if (field->flags & HIST_FIELD_FL_CPU)
+ field_name = "cpu";
+ else if (field->flags & HIST_FIELD_FL_EXPR ||
+ field->flags & HIST_FIELD_FL_VAR_REF) {
+ if (field->system) {
+ static char full_name[MAX_FILTER_STR_VAL];
+
+ strcat(full_name, field->system);
+ strcat(full_name, ".");
+ strcat(full_name, field->event_name);
+ strcat(full_name, ".");
+ strcat(full_name, field->name);
+ field_name = full_name;
+ } else
+ field_name = field->name;
+ } else if (field->flags & HIST_FIELD_FL_TIMESTAMP)
+ field_name = "common_timestamp";
+
+ if (field_name == NULL)
+ field_name = "";
+
+ return field_name;
+}
+
+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)
+{
+ unsigned int i;
+
+ if (!attrs)
+ return;
+
+ for (i = 0; i < attrs->n_assignments; i++)
+ kfree(attrs->assignment_str[i]);
+
+ for (i = 0; i < attrs->n_actions; i++)
+ kfree(attrs->action_str[i]);
+
+ kfree(attrs->name);
+ kfree(attrs->sort_key_str);
+ kfree(attrs->keys_str);
+ kfree(attrs->vals_str);
+ kfree(attrs->clock);
+ kfree(attrs);
+}
+
+static int parse_action(char *str, struct hist_trigger_attrs *attrs)
+{
+ int ret = -EINVAL;
+
+ if (attrs->n_actions >= HIST_ACTIONS_MAX)
+ return ret;
+
+ if ((strncmp(str, "onmatch(", strlen("onmatch(")) == 0) ||
+ (strncmp(str, "onmax(", strlen("onmax(")) == 0)) {
+ attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL);
+ if (!attrs->action_str[attrs->n_actions]) {
+ ret = -ENOMEM;
+ return ret;
+ }
+ attrs->n_actions++;
+ ret = 0;
+ }
+
+ return ret;
+}
+
+static int parse_assignment(char *str, struct hist_trigger_attrs *attrs)
+{
+ int ret = 0;
+
+ if ((strncmp(str, "key=", strlen("key=")) == 0) ||
+ (strncmp(str, "keys=", strlen("keys=")) == 0)) {
+ attrs->keys_str = kstrdup(str, GFP_KERNEL);
+ if (!attrs->keys_str) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ } 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);
+ if (!attrs->vals_str) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ } else if (strncmp(str, "sort=", strlen("sort=")) == 0) {
+ attrs->sort_key_str = kstrdup(str, GFP_KERNEL);
+ if (!attrs->sort_key_str) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ } else if (strncmp(str, "name=", strlen("name=")) == 0) {
+ attrs->name = kstrdup(str, GFP_KERNEL);
+ if (!attrs->name) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ } else if (strncmp(str, "clock=", strlen("clock=")) == 0) {
+ strsep(&str, "=");
+ if (!str) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ str = strstrip(str);
+ attrs->clock = kstrdup(str, GFP_KERNEL);
+ if (!attrs->clock) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ } else if (strncmp(str, "size=", strlen("size=")) == 0) {
+ int map_bits = parse_map_size(str);
+
+ if (map_bits < 0) {
+ ret = map_bits;
+ goto out;
+ }
+ attrs->map_bits = map_bits;
+ } else {
+ char *assignment;
+
+ if (attrs->n_assignments == TRACING_MAP_VARS_MAX) {
+ hist_err("Too many variables defined: ", str);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ assignment = kstrdup(str, GFP_KERNEL);
+ if (!assignment) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ attrs->assignment_str[attrs->n_assignments++] = assignment;
+ }
+ out:
+ return ret;
+}
+
+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 (strchr(str, '=')) {
+ ret = parse_assignment(str, attrs);
+ if (ret)
+ goto free;
+ } 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 {
+ ret = parse_action(str, attrs);
+ if (ret)
+ goto free;
+ }
+ }
+
+ if (!attrs->keys_str) {
+ ret = -EINVAL;
+ goto free;
+ }
+
+ if (!attrs->clock) {
+ attrs->clock = kstrdup("global", GFP_KERNEL);
+ if (!attrs->clock) {
+ ret = -ENOMEM;
+ 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_elt_data_free(struct hist_elt_data *elt_data)
+{
+ unsigned int i;
+
+ for (i = 0; i < SYNTH_FIELDS_MAX; i++)
+ kfree(elt_data->field_var_str[i]);
+
+ kfree(elt_data->comm);
+ kfree(elt_data);
+}
+
+static void hist_trigger_elt_data_free(struct tracing_map_elt *elt)
+{
+ struct hist_elt_data *elt_data = elt->private_data;
+
+ hist_elt_data_free(elt_data);
+}
+
+static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt)
+{
+ struct hist_trigger_data *hist_data = elt->map->private_data;
+ unsigned int size = TASK_COMM_LEN;
+ struct hist_elt_data *elt_data;
+ struct hist_field *key_field;
+ unsigned int i, n_str;
+
+ elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL);
+ if (!elt_data)
+ return -ENOMEM;
+
+ for_each_hist_key_field(i, hist_data) {
+ key_field = hist_data->fields[i];
+
+ if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
+ elt_data->comm = kzalloc(size, GFP_KERNEL);
+ if (!elt_data->comm) {
+ kfree(elt_data);
+ return -ENOMEM;
+ }
+ break;
+ }
+ }
+
+ n_str = hist_data->n_field_var_str + hist_data->n_max_var_str;
+
+ size = STR_VAR_LEN_MAX;
+
+ for (i = 0; i < n_str; i++) {
+ elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL);
+ if (!elt_data->field_var_str[i]) {
+ hist_elt_data_free(elt_data);
+ return -ENOMEM;
+ }
+ }
+
+ elt->private_data = elt_data;
+
+ return 0;
+}
+
+static void hist_trigger_elt_data_init(struct tracing_map_elt *elt)
+{
+ struct hist_elt_data *elt_data = elt->private_data;
+
+ if (elt_data->comm)
+ save_comm(elt_data->comm, current);
+}
+
+static const struct tracing_map_ops hist_trigger_elt_data_ops = {
+ .elt_alloc = hist_trigger_elt_data_alloc,
+ .elt_free = hist_trigger_elt_data_free,
+ .elt_init = hist_trigger_elt_data_init,
+};
+
+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";
+ else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS)
+ flags_str = "usecs";
+
+ return flags_str;
+}
+
+static void expr_field_str(struct hist_field *field, char *expr)
+{
+ if (field->flags & HIST_FIELD_FL_VAR_REF)
+ strcat(expr, "$");
+
+ strcat(expr, hist_field_name(field, 0));
+
+ if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) {
+ const char *flags_str = get_hist_field_flags(field);
+
+ if (flags_str) {
+ strcat(expr, ".");
+ strcat(expr, flags_str);
+ }
+ }
+}
+
+static char *expr_str(struct hist_field *field, unsigned int level)
+{
+ char *expr;
+
+ if (level > 1)
+ return NULL;
+
+ expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
+ if (!expr)
+ return NULL;
+
+ if (!field->operands[0]) {
+ expr_field_str(field, expr);
+ return expr;
+ }
+
+ if (field->operator == FIELD_OP_UNARY_MINUS) {
+ char *subexpr;
+
+ strcat(expr, "-(");
+ subexpr = expr_str(field->operands[0], ++level);
+ if (!subexpr) {
+ kfree(expr);
+ return NULL;
+ }
+ strcat(expr, subexpr);
+ strcat(expr, ")");
+
+ kfree(subexpr);
+
+ return expr;
+ }
+
+ expr_field_str(field->operands[0], expr);
+
+ switch (field->operator) {
+ case FIELD_OP_MINUS:
+ strcat(expr, "-");
+ break;
+ case FIELD_OP_PLUS:
+ strcat(expr, "+");
+ break;
+ default:
+ kfree(expr);
+ return NULL;
+ }
+
+ expr_field_str(field->operands[1], expr);
+
+ return expr;
+}
+
+static int contains_operator(char *str)
+{
+ enum field_op_id field_op = FIELD_OP_NONE;
+ char *op;
+
+ op = strpbrk(str, "+-");
+ if (!op)
+ return FIELD_OP_NONE;
+
+ switch (*op) {
+ case '-':
+ if (*str == '-')
+ field_op = FIELD_OP_UNARY_MINUS;
+ else
+ field_op = FIELD_OP_MINUS;
+ break;
+ case '+':
+ field_op = FIELD_OP_PLUS;
+ break;
+ default:
+ break;
+ }
+
+ return field_op;
+}
+
+static void destroy_hist_field(struct hist_field *hist_field,
+ unsigned int level)
+{
+ unsigned int i;
+
+ if (level > 3)
+ return;
+
+ if (!hist_field)
+ return;
+
+ for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++)
+ destroy_hist_field(hist_field->operands[i], level + 1);
+
+ kfree(hist_field->var.name);
+ kfree(hist_field->name);
+ kfree(hist_field->type);
+
+ kfree(hist_field);
+}
+
+static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
+ struct ftrace_event_field *field,
+ unsigned long flags,
+ char *var_name)
+{
+ 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;
+
+ hist_field->hist_data = hist_data;
+
+ if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS)
+ goto out; /* caller will populate */
+
+ if (flags & HIST_FIELD_FL_VAR_REF) {
+ hist_field->fn = hist_field_var_ref;
+ goto out;
+ }
+
+ if (flags & HIST_FIELD_FL_HITCOUNT) {
+ hist_field->fn = hist_field_counter;
+ hist_field->size = sizeof(u64);
+ hist_field->type = kstrdup("u64", GFP_KERNEL);
+ if (!hist_field->type)
+ goto free;
+ goto out;
+ }
+
+ if (flags & HIST_FIELD_FL_STACKTRACE) {
+ hist_field->fn = hist_field_none;
+ goto out;
+ }
+
+ if (flags & HIST_FIELD_FL_LOG2) {
+ unsigned long fl = flags & ~HIST_FIELD_FL_LOG2;
+ hist_field->fn = hist_field_log2;
+ hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL);
+ hist_field->size = hist_field->operands[0]->size;
+ hist_field->type = kstrdup(hist_field->operands[0]->type, GFP_KERNEL);
+ if (!hist_field->type)
+ goto free;
+ goto out;
+ }
+
+ if (flags & HIST_FIELD_FL_TIMESTAMP) {
+ hist_field->fn = hist_field_timestamp;
+ hist_field->size = sizeof(u64);
+ hist_field->type = kstrdup("u64", GFP_KERNEL);
+ if (!hist_field->type)
+ goto free;
+ goto out;
+ }
+
+ if (flags & HIST_FIELD_FL_CPU) {
+ hist_field->fn = hist_field_cpu;
+ hist_field->size = sizeof(int);
+ hist_field->type = kstrdup("unsigned int", GFP_KERNEL);
+ if (!hist_field->type)
+ goto free;
+ goto out;
+ }
+
+ if (WARN_ON_ONCE(!field))
+ goto out;
+
+ if (is_string_field(field)) {
+ flags |= HIST_FIELD_FL_STRING;
+
+ hist_field->size = MAX_FILTER_STR_VAL;
+ hist_field->type = kstrdup(field->type, GFP_KERNEL);
+ if (!hist_field->type)
+ goto free;
+
+ 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->size = field->size;
+ hist_field->is_signed = field->is_signed;
+ hist_field->type = kstrdup(field->type, GFP_KERNEL);
+ if (!hist_field->type)
+ goto free;
+
+ hist_field->fn = select_value_fn(field->size,
+ field->is_signed);
+ if (!hist_field->fn) {
+ destroy_hist_field(hist_field, 0);
+ return NULL;
+ }
+ }
+ out:
+ hist_field->field = field;
+ hist_field->flags = flags;
+
+ if (var_name) {
+ hist_field->var.name = kstrdup(var_name, GFP_KERNEL);
+ if (!hist_field->var.name)
+ goto free;
+ }
+
+ return hist_field;
+ free:
+ destroy_hist_field(hist_field, 0);
+ return NULL;
+}
+
+static void destroy_hist_fields(struct hist_trigger_data *hist_data)
+{
+ unsigned int i;
+
+ for (i = 0; i < HIST_FIELDS_MAX; i++) {
+ if (hist_data->fields[i]) {
+ destroy_hist_field(hist_data->fields[i], 0);
+ hist_data->fields[i] = NULL;
+ }
+ }
+}
+
+static int init_var_ref(struct hist_field *ref_field,
+ struct hist_field *var_field,
+ char *system, char *event_name)
+{
+ int err = 0;
+
+ ref_field->var.idx = var_field->var.idx;
+ ref_field->var.hist_data = var_field->hist_data;
+ ref_field->size = var_field->size;
+ ref_field->is_signed = var_field->is_signed;
+ ref_field->flags |= var_field->flags &
+ (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
+
+ if (system) {
+ ref_field->system = kstrdup(system, GFP_KERNEL);
+ if (!ref_field->system)
+ return -ENOMEM;
+ }
+
+ if (event_name) {
+ ref_field->event_name = kstrdup(event_name, GFP_KERNEL);
+ if (!ref_field->event_name) {
+ err = -ENOMEM;
+ goto free;
+ }
+ }
+
+ if (var_field->var.name) {
+ ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL);
+ if (!ref_field->name) {
+ err = -ENOMEM;
+ goto free;
+ }
+ } else if (var_field->name) {
+ ref_field->name = kstrdup(var_field->name, GFP_KERNEL);
+ if (!ref_field->name) {
+ err = -ENOMEM;
+ goto free;
+ }
+ }
+
+ ref_field->type = kstrdup(var_field->type, GFP_KERNEL);
+ if (!ref_field->type) {
+ err = -ENOMEM;
+ goto free;
+ }
+ out:
+ return err;
+ free:
+ kfree(ref_field->system);
+ kfree(ref_field->event_name);
+ kfree(ref_field->name);
+
+ goto out;
+}
+
+static struct hist_field *create_var_ref(struct hist_field *var_field,
+ char *system, char *event_name)
+{
+ unsigned long flags = HIST_FIELD_FL_VAR_REF;
+ struct hist_field *ref_field;
+
+ ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL);
+ if (ref_field) {
+ if (init_var_ref(ref_field, var_field, system, event_name)) {
+ destroy_hist_field(ref_field, 0);
+ return NULL;
+ }
+ }
+
+ return ref_field;
+}
+
+static bool is_var_ref(char *var_name)
+{
+ if (!var_name || strlen(var_name) < 2 || var_name[0] != '$')
+ return false;
+
+ return true;
+}
+
+static char *field_name_from_var(struct hist_trigger_data *hist_data,
+ char *var_name)
+{
+ char *name, *field;
+ unsigned int i;
+
+ for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) {
+ name = hist_data->attrs->var_defs.name[i];
+
+ if (strcmp(var_name, name) == 0) {
+ field = hist_data->attrs->var_defs.expr[i];
+ if (contains_operator(field) || is_var_ref(field))
+ continue;
+ return field;
+ }
+ }
+
+ return NULL;
+}
+
+static char *local_field_var_ref(struct hist_trigger_data *hist_data,
+ char *system, char *event_name,
+ char *var_name)
+{
+ struct trace_event_call *call;
+
+ if (system && event_name) {
+ call = hist_data->event_file->event_call;
+
+ if (strcmp(system, call->class->system) != 0)
+ return NULL;
+
+ if (strcmp(event_name, trace_event_name(call)) != 0)
+ return NULL;
+ }
+
+ if (!!system != !!event_name)
+ return NULL;
+
+ if (!is_var_ref(var_name))
+ return NULL;
+
+ var_name++;
+
+ return field_name_from_var(hist_data, var_name);
+}
+
+static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data,
+ char *system, char *event_name,
+ char *var_name)
+{
+ struct hist_field *var_field = NULL, *ref_field = NULL;
+
+ if (!is_var_ref(var_name))
+ return NULL;
+
+ var_name++;
+
+ var_field = find_event_var(hist_data, system, event_name, var_name);
+ if (var_field)
+ ref_field = create_var_ref(var_field, system, event_name);
+
+ if (!ref_field)
+ hist_err_event("Couldn't find variable: $",
+ system, event_name, var_name);
+
+ return ref_field;
+}
+
+static struct ftrace_event_field *
+parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file,
+ char *field_str, unsigned long *flags)
+{
+ struct ftrace_event_field *field = NULL;
+ char *field_name, *modifier, *str;
+
+ modifier = str = kstrdup(field_str, GFP_KERNEL);
+ if (!modifier)
+ return ERR_PTR(-ENOMEM);
+
+ field_name = strsep(&modifier, ".");
+ if (modifier) {
+ if (strcmp(modifier, "hex") == 0)
+ *flags |= HIST_FIELD_FL_HEX;
+ else if (strcmp(modifier, "sym") == 0)
+ *flags |= HIST_FIELD_FL_SYM;
+ else if (strcmp(modifier, "sym-offset") == 0)
+ *flags |= HIST_FIELD_FL_SYM_OFFSET;
+ else if ((strcmp(modifier, "execname") == 0) &&
+ (strcmp(field_name, "common_pid") == 0))
+ *flags |= HIST_FIELD_FL_EXECNAME;
+ else if (strcmp(modifier, "syscall") == 0)
+ *flags |= HIST_FIELD_FL_SYSCALL;
+ else if (strcmp(modifier, "log2") == 0)
+ *flags |= HIST_FIELD_FL_LOG2;
+ else if (strcmp(modifier, "usecs") == 0)
+ *flags |= HIST_FIELD_FL_TIMESTAMP_USECS;
+ else {
+ hist_err("Invalid field modifier: ", modifier);
+ field = ERR_PTR(-EINVAL);
+ goto out;
+ }
+ }
+
+ if (strcmp(field_name, "common_timestamp") == 0) {
+ *flags |= HIST_FIELD_FL_TIMESTAMP;
+ hist_data->enable_timestamps = true;
+ if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS)
+ hist_data->attrs->ts_in_usecs = true;
+ } else if (strcmp(field_name, "cpu") == 0)
+ *flags |= HIST_FIELD_FL_CPU;
+ else {
+ field = trace_find_event_field(file->event_call, field_name);
+ if (!field || !field->size) {
+ hist_err("Couldn't find field: ", field_name);
+ field = ERR_PTR(-EINVAL);
+ goto out;
+ }
+ }
+ out:
+ kfree(str);
+
+ return field;
+}
+
+static struct hist_field *create_alias(struct hist_trigger_data *hist_data,
+ struct hist_field *var_ref,
+ char *var_name)
+{
+ struct hist_field *alias = NULL;
+ unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR;
+
+ alias = create_hist_field(hist_data, NULL, flags, var_name);
+ if (!alias)
+ return NULL;
+
+ alias->fn = var_ref->fn;
+ alias->operands[0] = var_ref;
+
+ if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) {
+ destroy_hist_field(alias, 0);
+ return NULL;
+ }
+
+ return alias;
+}
+
+static struct hist_field *parse_atom(struct hist_trigger_data *hist_data,
+ struct trace_event_file *file, char *str,
+ unsigned long *flags, char *var_name)
+{
+ char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str;
+ struct ftrace_event_field *field = NULL;
+ struct hist_field *hist_field = NULL;
+ int ret = 0;
+
+ s = strchr(str, '.');
+ if (s) {
+ s = strchr(++s, '.');
+ if (s) {
+ ref_system = strsep(&str, ".");
+ if (!str) {
+ ret = -EINVAL;
+ goto out;
+ }
+ ref_event = strsep(&str, ".");
+ if (!str) {
+ ret = -EINVAL;
+ goto out;
+ }
+ ref_var = str;
+ }
+ }
+
+ s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var);
+ if (!s) {
+ hist_field = parse_var_ref(hist_data, ref_system, ref_event, ref_var);
+ if (hist_field) {
+ hist_data->var_refs[hist_data->n_var_refs] = hist_field;
+ hist_field->var_ref_idx = hist_data->n_var_refs++;
+ if (var_name) {
+ hist_field = create_alias(hist_data, hist_field, var_name);
+ if (!hist_field) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ }
+ return hist_field;
+ }
+ } else
+ str = s;
+
+ field = parse_field(hist_data, file, str, flags);
+ if (IS_ERR(field)) {
+ ret = PTR_ERR(field);
+ goto out;
+ }
+
+ hist_field = create_hist_field(hist_data, field, *flags, var_name);
+ if (!hist_field) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ return hist_field;
+ out:
+ return ERR_PTR(ret);
+}
+
+static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
+ struct trace_event_file *file,
+ char *str, unsigned long flags,
+ char *var_name, unsigned int level);
+
+static struct hist_field *parse_unary(struct hist_trigger_data *hist_data,
+ struct trace_event_file *file,
+ char *str, unsigned long flags,
+ char *var_name, unsigned int level)
+{
+ struct hist_field *operand1, *expr = NULL;
+ unsigned long operand_flags;
+ int ret = 0;
+ char *s;
+
+ /* we support only -(xxx) i.e. explicit parens required */
+
+ if (level > 3) {
+ hist_err("Too many subexpressions (3 max): ", str);
+ ret = -EINVAL;
+ goto free;
+ }
+
+ str++; /* skip leading '-' */
+
+ s = strchr(str, '(');
+ if (s)
+ str++;
+ else {
+ ret = -EINVAL;
+ goto free;
+ }
+
+ s = strrchr(str, ')');
+ if (s)
+ *s = '\0';
+ else {
+ ret = -EINVAL; /* no closing ')' */
+ goto free;
+ }
+
+ flags |= HIST_FIELD_FL_EXPR;
+ expr = create_hist_field(hist_data, NULL, flags, var_name);
+ if (!expr) {
+ ret = -ENOMEM;
+ goto free;
+ }
+
+ operand_flags = 0;
+ operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level);
+ if (IS_ERR(operand1)) {
+ ret = PTR_ERR(operand1);
+ goto free;
+ }
+
+ expr->flags |= operand1->flags &
+ (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
+ expr->fn = hist_field_unary_minus;
+ expr->operands[0] = operand1;
+ expr->operator = FIELD_OP_UNARY_MINUS;
+ expr->name = expr_str(expr, 0);
+ expr->type = kstrdup(operand1->type, GFP_KERNEL);
+ if (!expr->type) {
+ ret = -ENOMEM;
+ goto free;
+ }
+
+ return expr;
+ free:
+ destroy_hist_field(expr, 0);
+ return ERR_PTR(ret);
+}
+
+static int check_expr_operands(struct hist_field *operand1,
+ struct hist_field *operand2)
+{
+ unsigned long operand1_flags = operand1->flags;
+ unsigned long operand2_flags = operand2->flags;
+
+ if ((operand1_flags & HIST_FIELD_FL_VAR_REF) ||
+ (operand1_flags & HIST_FIELD_FL_ALIAS)) {
+ struct hist_field *var;
+
+ var = find_var_field(operand1->var.hist_data, operand1->name);
+ if (!var)
+ return -EINVAL;
+ operand1_flags = var->flags;
+ }
+
+ if ((operand2_flags & HIST_FIELD_FL_VAR_REF) ||
+ (operand2_flags & HIST_FIELD_FL_ALIAS)) {
+ struct hist_field *var;
+
+ var = find_var_field(operand2->var.hist_data, operand2->name);
+ if (!var)
+ return -EINVAL;
+ operand2_flags = var->flags;
+ }
+
+ if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) !=
+ (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) {
+ hist_err("Timestamp units in expression don't match", NULL);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
+ struct trace_event_file *file,
+ char *str, unsigned long flags,
+ char *var_name, unsigned int level)
+{
+ struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL;
+ unsigned long operand_flags;
+ int field_op, ret = -EINVAL;
+ char *sep, *operand1_str;
+
+ if (level > 3) {
+ hist_err("Too many subexpressions (3 max): ", str);
+ return ERR_PTR(-EINVAL);
+ }
+
+ field_op = contains_operator(str);
+
+ if (field_op == FIELD_OP_NONE)
+ return parse_atom(hist_data, file, str, &flags, var_name);
+
+ if (field_op == FIELD_OP_UNARY_MINUS)
+ return parse_unary(hist_data, file, str, flags, var_name, ++level);
+
+ switch (field_op) {
+ case FIELD_OP_MINUS:
+ sep = "-";
+ break;
+ case FIELD_OP_PLUS:
+ sep = "+";
+ break;
+ default:
+ goto free;
+ }
+
+ operand1_str = strsep(&str, sep);
+ if (!operand1_str || !str)
+ goto free;
+
+ operand_flags = 0;
+ operand1 = parse_atom(hist_data, file, operand1_str,
+ &operand_flags, NULL);
+ if (IS_ERR(operand1)) {
+ ret = PTR_ERR(operand1);
+ operand1 = NULL;
+ goto free;
+ }
+
+ /* rest of string could be another expression e.g. b+c in a+b+c */
+ operand_flags = 0;
+ operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level);
+ if (IS_ERR(operand2)) {
+ ret = PTR_ERR(operand2);
+ operand2 = NULL;
+ goto free;
+ }
+
+ ret = check_expr_operands(operand1, operand2);
+ if (ret)
+ goto free;
+
+ flags |= HIST_FIELD_FL_EXPR;
+
+ flags |= operand1->flags &
+ (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
+
+ expr = create_hist_field(hist_data, NULL, flags, var_name);
+ if (!expr) {
+ ret = -ENOMEM;
+ goto free;
+ }
+
+ operand1->read_once = true;
+ operand2->read_once = true;
+
+ expr->operands[0] = operand1;
+ expr->operands[1] = operand2;
+ expr->operator = field_op;
+ expr->name = expr_str(expr, 0);
+ expr->type = kstrdup(operand1->type, GFP_KERNEL);
+ if (!expr->type) {
+ ret = -ENOMEM;
+ goto free;
+ }
+
+ switch (field_op) {
+ case FIELD_OP_MINUS:
+ expr->fn = hist_field_minus;
+ break;
+ case FIELD_OP_PLUS:
+ expr->fn = hist_field_plus;
+ break;
+ default:
+ ret = -EINVAL;
+ goto free;
+ }
+
+ return expr;
+ free:
+ destroy_hist_field(operand1, 0);
+ destroy_hist_field(operand2, 0);
+ destroy_hist_field(expr, 0);
+
+ return ERR_PTR(ret);
+}
+
+static char *find_trigger_filter(struct hist_trigger_data *hist_data,
+ 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) {
+ if (test->private_data == hist_data)
+ return test->filter_str;
+ }
+ }
+
+ return NULL;
+}
+
+static struct event_command trigger_hist_cmd;
+static int event_hist_trigger_func(struct event_command *cmd_ops,
+ struct trace_event_file *file,
+ char *glob, char *cmd, char *param);
+
+static bool compatible_keys(struct hist_trigger_data *target_hist_data,
+ struct hist_trigger_data *hist_data,
+ unsigned int n_keys)
+{
+ struct hist_field *target_hist_field, *hist_field;
+ unsigned int n, i, j;
+
+ if (hist_data->n_fields - hist_data->n_vals != n_keys)
+ return false;
+
+ i = hist_data->n_vals;
+ j = target_hist_data->n_vals;
+
+ for (n = 0; n < n_keys; n++) {
+ hist_field = hist_data->fields[i + n];
+ target_hist_field = target_hist_data->fields[j + n];
+
+ if (strcmp(hist_field->type, target_hist_field->type) != 0)
+ return false;
+ if (hist_field->size != target_hist_field->size)
+ return false;
+ if (hist_field->is_signed != target_hist_field->is_signed)
+ return false;
+ }
+
+ return true;
+}
+
+static struct hist_trigger_data *
+find_compatible_hist(struct hist_trigger_data *target_hist_data,
+ struct trace_event_file *file)
+{
+ struct hist_trigger_data *hist_data;
+ struct event_trigger_data *test;
+ unsigned int n_keys;
+
+ n_keys = target_hist_data->n_fields - target_hist_data->n_vals;
+
+ list_for_each_entry_rcu(test, &file->triggers, list) {
+ if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
+ hist_data = test->private_data;
+
+ if (compatible_keys(target_hist_data, hist_data, n_keys))
+ return hist_data;
+ }
+ }
+
+ return NULL;
+}
+
+static struct trace_event_file *event_file(struct trace_array *tr,
+ char *system, char *event_name)
+{
+ struct trace_event_file *file;
+
+ file = __find_event_file(tr, system, event_name);
+ if (!file)
+ return ERR_PTR(-EINVAL);
+
+ return file;
+}
+
+static struct hist_field *
+find_synthetic_field_var(struct hist_trigger_data *target_hist_data,
+ char *system, char *event_name, char *field_name)
+{
+ struct hist_field *event_var;
+ char *synthetic_name;
+
+ synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
+ if (!synthetic_name)
+ return ERR_PTR(-ENOMEM);
+
+ strcpy(synthetic_name, "synthetic_");
+ strcat(synthetic_name, field_name);
+
+ event_var = find_event_var(target_hist_data, system, event_name, synthetic_name);
+
+ kfree(synthetic_name);
+
+ return event_var;
+}
+
+/**
+ * create_field_var_hist - Automatically create a histogram and var for a field
+ * @target_hist_data: The target hist trigger
+ * @subsys_name: Optional subsystem name
+ * @event_name: Optional event name
+ * @field_name: The name of the field (and the resulting variable)
+ *
+ * Hist trigger actions fetch data from variables, not directly from
+ * events. However, for convenience, users are allowed to directly
+ * specify an event field in an action, which will be automatically
+ * converted into a variable on their behalf.
+
+ * If a user specifies a field on an event that isn't the event the
+ * histogram currently being defined (the target event histogram), the
+ * only way that can be accomplished is if a new hist trigger is
+ * created and the field variable defined on that.
+ *
+ * This function creates a new histogram compatible with the target
+ * event (meaning a histogram with the same key as the target
+ * histogram), and creates a variable for the specified field, but
+ * with 'synthetic_' prepended to the variable name in order to avoid
+ * collision with normal field variables.
+ *
+ * Return: The variable created for the field.
+ */
+static struct hist_field *
+create_field_var_hist(struct hist_trigger_data *target_hist_data,
+ char *subsys_name, char *event_name, char *field_name)
+{
+ struct trace_array *tr = target_hist_data->event_file->tr;
+ struct hist_field *event_var = ERR_PTR(-EINVAL);
+ struct hist_trigger_data *hist_data;
+ unsigned int i, n, first = true;
+ struct field_var_hist *var_hist;
+ struct trace_event_file *file;
+ struct hist_field *key_field;
+ char *saved_filter;
+ char *cmd;
+ int ret;
+
+ if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) {
+ hist_err_event("onmatch: Too many field variables defined: ",
+ subsys_name, event_name, field_name);
+ return ERR_PTR(-EINVAL);
+ }
+
+ file = event_file(tr, subsys_name, event_name);
+
+ if (IS_ERR(file)) {
+ hist_err_event("onmatch: Event file not found: ",
+ subsys_name, event_name, field_name);
+ ret = PTR_ERR(file);
+ return ERR_PTR(ret);
+ }
+
+ /*
+ * Look for a histogram compatible with target. We'll use the
+ * found histogram specification to create a new matching
+ * histogram with our variable on it. target_hist_data is not
+ * yet a registered histogram so we can't use that.
+ */
+ hist_data = find_compatible_hist(target_hist_data, file);
+ if (!hist_data) {
+ hist_err_event("onmatch: Matching event histogram not found: ",
+ subsys_name, event_name, field_name);
+ return ERR_PTR(-EINVAL);
+ }
+
+ /* See if a synthetic field variable has already been created */
+ event_var = find_synthetic_field_var(target_hist_data, subsys_name,
+ event_name, field_name);
+ if (!IS_ERR_OR_NULL(event_var))
+ return event_var;
+
+ var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL);
+ if (!var_hist)
+ return ERR_PTR(-ENOMEM);
+
+ cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
+ if (!cmd) {
+ kfree(var_hist);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ /* Use the same keys as the compatible histogram */
+ strcat(cmd, "keys=");
+
+ for_each_hist_key_field(i, hist_data) {
+ key_field = hist_data->fields[i];
+ if (!first)
+ strcat(cmd, ",");
+ strcat(cmd, key_field->field->name);
+ first = false;
+ }
+
+ /* Create the synthetic field variable specification */
+ strcat(cmd, ":synthetic_");
+ strcat(cmd, field_name);
+ strcat(cmd, "=");
+ strcat(cmd, field_name);
+
+ /* Use the same filter as the compatible histogram */
+ saved_filter = find_trigger_filter(hist_data, file);
+ if (saved_filter) {
+ strcat(cmd, " if ");
+ strcat(cmd, saved_filter);
+ }
+
+ var_hist->cmd = kstrdup(cmd, GFP_KERNEL);
+ if (!var_hist->cmd) {
+ kfree(cmd);
+ kfree(var_hist);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ /* Save the compatible histogram information */
+ var_hist->hist_data = hist_data;
+
+ /* Create the new histogram with our variable */
+ ret = event_hist_trigger_func(&trigger_hist_cmd, file,
+ "", "hist", cmd);
+ if (ret) {
+ kfree(cmd);
+ kfree(var_hist->cmd);
+ kfree(var_hist);
+ hist_err_event("onmatch: Couldn't create histogram for field: ",
+ subsys_name, event_name, field_name);
+ return ERR_PTR(ret);
+ }
+
+ kfree(cmd);
+
+ /* If we can't find the variable, something went wrong */
+ event_var = find_synthetic_field_var(target_hist_data, subsys_name,
+ event_name, field_name);
+ if (IS_ERR_OR_NULL(event_var)) {
+ kfree(var_hist->cmd);
+ kfree(var_hist);
+ hist_err_event("onmatch: Couldn't find synthetic variable: ",
+ subsys_name, event_name, field_name);
+ return ERR_PTR(-EINVAL);
+ }
+
+ n = target_hist_data->n_field_var_hists;
+ target_hist_data->field_var_hists[n] = var_hist;
+ target_hist_data->n_field_var_hists++;
+
+ return event_var;
+}
+
+static struct hist_field *
+find_target_event_var(struct hist_trigger_data *hist_data,
+ char *subsys_name, char *event_name, char *var_name)
+{
+ struct trace_event_file *file = hist_data->event_file;
+ struct hist_field *hist_field = NULL;
+
+ if (subsys_name) {
+ struct trace_event_call *call;
+
+ if (!event_name)
+ return NULL;
+
+ call = file->event_call;
+
+ if (strcmp(subsys_name, call->class->system) != 0)
+ return NULL;
+
+ if (strcmp(event_name, trace_event_name(call)) != 0)
+ return NULL;
+ }
+
+ hist_field = find_var_field(hist_data, var_name);
+
+ return hist_field;
+}
+
+static inline void __update_field_vars(struct tracing_map_elt *elt,
+ struct ring_buffer_event *rbe,
+ void *rec,
+ struct field_var **field_vars,
+ unsigned int n_field_vars,
+ unsigned int field_var_str_start)
+{
+ struct hist_elt_data *elt_data = elt->private_data;
+ unsigned int i, j, var_idx;
+ u64 var_val;
+
+ for (i = 0, j = field_var_str_start; i < n_field_vars; i++) {
+ struct field_var *field_var = field_vars[i];
+ struct hist_field *var = field_var->var;
+ struct hist_field *val = field_var->val;
+
+ var_val = val->fn(val, elt, rbe, rec);
+ var_idx = var->var.idx;
+
+ if (val->flags & HIST_FIELD_FL_STRING) {
+ char *str = elt_data->field_var_str[j++];
+ char *val_str = (char *)(uintptr_t)var_val;
+
+ strscpy(str, val_str, STR_VAR_LEN_MAX);
+ var_val = (u64)(uintptr_t)str;
+ }
+ tracing_map_set_var(elt, var_idx, var_val);
+ }
+}
+
+static void update_field_vars(struct hist_trigger_data *hist_data,
+ struct tracing_map_elt *elt,
+ struct ring_buffer_event *rbe,
+ void *rec)
+{
+ __update_field_vars(elt, rbe, rec, hist_data->field_vars,
+ hist_data->n_field_vars, 0);
+}
+
+static void update_max_vars(struct hist_trigger_data *hist_data,
+ struct tracing_map_elt *elt,
+ struct ring_buffer_event *rbe,
+ void *rec)
+{
+ __update_field_vars(elt, rbe, rec, hist_data->max_vars,
+ hist_data->n_max_vars, hist_data->n_field_var_str);
+}
+
+static struct hist_field *create_var(struct hist_trigger_data *hist_data,
+ struct trace_event_file *file,
+ char *name, int size, const char *type)
+{
+ struct hist_field *var;
+ int idx;
+
+ if (find_var(hist_data, file, name) && !hist_data->remove) {
+ var = ERR_PTR(-EINVAL);
+ goto out;
+ }
+
+ var = kzalloc(sizeof(struct hist_field), GFP_KERNEL);
+ if (!var) {
+ var = ERR_PTR(-ENOMEM);
+ goto out;
+ }
+
+ idx = tracing_map_add_var(hist_data->map);
+ if (idx < 0) {
+ kfree(var);
+ var = ERR_PTR(-EINVAL);
+ goto out;
+ }
+
+ var->flags = HIST_FIELD_FL_VAR;
+ var->var.idx = idx;
+ var->var.hist_data = var->hist_data = hist_data;
+ var->size = size;
+ var->var.name = kstrdup(name, GFP_KERNEL);
+ var->type = kstrdup(type, GFP_KERNEL);
+ if (!var->var.name || !var->type) {
+ kfree(var->var.name);
+ kfree(var->type);
+ kfree(var);
+ var = ERR_PTR(-ENOMEM);
+ }
+ out:
+ return var;
+}
+
+static struct field_var *create_field_var(struct hist_trigger_data *hist_data,
+ struct trace_event_file *file,
+ char *field_name)
+{
+ struct hist_field *val = NULL, *var = NULL;
+ unsigned long flags = HIST_FIELD_FL_VAR;
+ struct field_var *field_var;
+ int ret = 0;
+
+ if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) {
+ hist_err("Too many field variables defined: ", field_name);
+ ret = -EINVAL;
+ goto err;
+ }
+
+ val = parse_atom(hist_data, file, field_name, &flags, NULL);
+ if (IS_ERR(val)) {
+ hist_err("Couldn't parse field variable: ", field_name);
+ ret = PTR_ERR(val);
+ goto err;
+ }
+
+ var = create_var(hist_data, file, field_name, val->size, val->type);
+ if (IS_ERR(var)) {
+ hist_err("Couldn't create or find variable: ", field_name);
+ kfree(val);
+ ret = PTR_ERR(var);
+ goto err;
+ }
+
+ field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL);
+ if (!field_var) {
+ kfree(val);
+ kfree(var);
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ field_var->var = var;
+ field_var->val = val;
+ out:
+ return field_var;
+ err:
+ field_var = ERR_PTR(ret);
+ goto out;
+}
+
+/**
+ * create_target_field_var - Automatically create a variable for a field
+ * @target_hist_data: The target hist trigger
+ * @subsys_name: Optional subsystem name
+ * @event_name: Optional event name
+ * @var_name: The name of the field (and the resulting variable)
+ *
+ * Hist trigger actions fetch data from variables, not directly from
+ * events. However, for convenience, users are allowed to directly
+ * specify an event field in an action, which will be automatically
+ * converted into a variable on their behalf.
+
+ * This function creates a field variable with the name var_name on
+ * the hist trigger currently being defined on the target event. If
+ * subsys_name and event_name are specified, this function simply
+ * verifies that they do in fact match the target event subsystem and
+ * event name.
+ *
+ * Return: The variable created for the field.
+ */
+static struct field_var *
+create_target_field_var(struct hist_trigger_data *target_hist_data,
+ char *subsys_name, char *event_name, char *var_name)
+{
+ struct trace_event_file *file = target_hist_data->event_file;
+
+ if (subsys_name) {
+ struct trace_event_call *call;
+
+ if (!event_name)
+ return NULL;
+
+ call = file->event_call;
+
+ if (strcmp(subsys_name, call->class->system) != 0)
+ return NULL;
+
+ if (strcmp(event_name, trace_event_name(call)) != 0)
+ return NULL;
+ }
+
+ return create_field_var(target_hist_data, file, var_name);
+}
+
+static void onmax_print(struct seq_file *m,
+ struct hist_trigger_data *hist_data,
+ struct tracing_map_elt *elt,
+ struct action_data *data)
+{
+ unsigned int i, save_var_idx, max_idx = data->onmax.max_var->var.idx;
+
+ seq_printf(m, "\n\tmax: %10llu", tracing_map_read_var(elt, max_idx));
+
+ for (i = 0; i < hist_data->n_max_vars; i++) {
+ struct hist_field *save_val = hist_data->max_vars[i]->val;
+ struct hist_field *save_var = hist_data->max_vars[i]->var;
+ u64 val;
+
+ save_var_idx = save_var->var.idx;
+
+ val = tracing_map_read_var(elt, save_var_idx);
+
+ if (save_val->flags & HIST_FIELD_FL_STRING) {
+ seq_printf(m, " %s: %-32s", save_var->var.name,
+ (char *)(uintptr_t)(val));
+ } else
+ seq_printf(m, " %s: %10llu", save_var->var.name, val);
+ }
+}
+
+static void onmax_save(struct hist_trigger_data *hist_data,
+ struct tracing_map_elt *elt, void *rec,
+ struct ring_buffer_event *rbe,
+ struct action_data *data, u64 *var_ref_vals)
+{
+ unsigned int max_idx = data->onmax.max_var->var.idx;
+ unsigned int max_var_ref_idx = data->onmax.max_var_ref_idx;
+
+ u64 var_val, max_val;
+
+ var_val = var_ref_vals[max_var_ref_idx];
+ max_val = tracing_map_read_var(elt, max_idx);
+
+ if (var_val <= max_val)
+ return;
+
+ tracing_map_set_var(elt, max_idx, var_val);
+
+ update_max_vars(hist_data, elt, rbe, rec);
+}
+
+static void onmax_destroy(struct action_data *data)
+{
+ unsigned int i;
+
+ destroy_hist_field(data->onmax.max_var, 0);
+ destroy_hist_field(data->onmax.var, 0);
+
+ kfree(data->onmax.var_str);
+ kfree(data->onmax.fn_name);
+
+ for (i = 0; i < data->n_params; i++)
+ kfree(data->params[i]);
+
+ kfree(data);
+}
+
+static int onmax_create(struct hist_trigger_data *hist_data,
+ struct action_data *data)
+{
+ struct trace_event_file *file = hist_data->event_file;
+ struct hist_field *var_field, *ref_field, *max_var;
+ unsigned int var_ref_idx = hist_data->n_var_refs;
+ struct field_var *field_var;
+ char *onmax_var_str, *param;
+ unsigned long flags;
+ unsigned int i;
+ int ret = 0;
+
+ onmax_var_str = data->onmax.var_str;
+ if (onmax_var_str[0] != '$') {
+ hist_err("onmax: For onmax(x), x must be a variable: ", onmax_var_str);
+ return -EINVAL;
+ }
+ onmax_var_str++;
+
+ var_field = find_target_event_var(hist_data, NULL, NULL, onmax_var_str);
+ if (!var_field) {
+ hist_err("onmax: Couldn't find onmax variable: ", onmax_var_str);
+ return -EINVAL;
+ }
+
+ flags = HIST_FIELD_FL_VAR_REF;
+ ref_field = create_hist_field(hist_data, NULL, flags, NULL);
+ if (!ref_field)
+ return -ENOMEM;
+
+ if (init_var_ref(ref_field, var_field, NULL, NULL)) {
+ destroy_hist_field(ref_field, 0);
+ ret = -ENOMEM;
+ goto out;
+ }
+ hist_data->var_refs[hist_data->n_var_refs] = ref_field;
+ ref_field->var_ref_idx = hist_data->n_var_refs++;
+ data->onmax.var = ref_field;
+
+ data->fn = onmax_save;
+ data->onmax.max_var_ref_idx = var_ref_idx;
+ max_var = create_var(hist_data, file, "max", sizeof(u64), "u64");
+ if (IS_ERR(max_var)) {
+ hist_err("onmax: Couldn't create onmax variable: ", "max");
+ ret = PTR_ERR(max_var);
+ goto out;
+ }
+ data->onmax.max_var = max_var;
+
+ for (i = 0; i < data->n_params; i++) {
+ param = kstrdup(data->params[i], GFP_KERNEL);
+ if (!param) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ field_var = create_target_field_var(hist_data, NULL, NULL, param);
+ if (IS_ERR(field_var)) {
+ hist_err("onmax: Couldn't create field variable: ", param);
+ ret = PTR_ERR(field_var);
+ kfree(param);
+ goto out;
+ }
+
+ hist_data->max_vars[hist_data->n_max_vars++] = field_var;
+ if (field_var->val->flags & HIST_FIELD_FL_STRING)
+ hist_data->n_max_var_str++;
+
+ kfree(param);
+ }
+ out:
+ return ret;
+}
+
+static int parse_action_params(char *params, struct action_data *data)
+{
+ char *param, *saved_param;
+ int ret = 0;
+
+ while (params) {
+ if (data->n_params >= SYNTH_FIELDS_MAX)
+ goto out;
+
+ param = strsep(¶ms, ",");
+ if (!param) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ param = strstrip(param);
+ if (strlen(param) < 2) {
+ hist_err("Invalid action param: ", param);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ saved_param = kstrdup(param, GFP_KERNEL);
+ if (!saved_param) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ data->params[data->n_params++] = saved_param;
+ }
+ out:
+ return ret;
+}
+
+static struct action_data *onmax_parse(char *str)
+{
+ char *onmax_fn_name, *onmax_var_str;
+ struct action_data *data;
+ int ret = -EINVAL;
+
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return ERR_PTR(-ENOMEM);
+
+ onmax_var_str = strsep(&str, ")");
+ if (!onmax_var_str || !str) {
+ ret = -EINVAL;
+ goto free;
+ }
+
+ data->onmax.var_str = kstrdup(onmax_var_str, GFP_KERNEL);
+ if (!data->onmax.var_str) {
+ ret = -ENOMEM;
+ goto free;
+ }
+
+ strsep(&str, ".");
+ if (!str)
+ goto free;
+
+ onmax_fn_name = strsep(&str, "(");
+ if (!onmax_fn_name || !str)
+ goto free;
+
+ if (strncmp(onmax_fn_name, "save", strlen("save")) == 0) {
+ char *params = strsep(&str, ")");
+
+ if (!params) {
+ ret = -EINVAL;
+ goto free;
+ }
+
+ ret = parse_action_params(params, data);
+ if (ret)
+ goto free;
+ } else
+ goto free;
+
+ data->onmax.fn_name = kstrdup(onmax_fn_name, GFP_KERNEL);
+ if (!data->onmax.fn_name) {
+ ret = -ENOMEM;
+ goto free;
+ }
+ out:
+ return data;
+ free:
+ onmax_destroy(data);
+ data = ERR_PTR(ret);
+ goto out;
+}
+
+static void onmatch_destroy(struct action_data *data)
+{
+ unsigned int i;
+
+ mutex_lock(&synth_event_mutex);
+
+ kfree(data->onmatch.match_event);
+ kfree(data->onmatch.match_event_system);
+ kfree(data->onmatch.synth_event_name);
+
+ for (i = 0; i < data->n_params; i++)
+ kfree(data->params[i]);
+
+ if (data->onmatch.synth_event)
+ data->onmatch.synth_event->ref--;
+
+ kfree(data);
+
+ mutex_unlock(&synth_event_mutex);
+}
+
+static void destroy_field_var(struct field_var *field_var)
+{
+ if (!field_var)
+ return;
+
+ destroy_hist_field(field_var->var, 0);
+ destroy_hist_field(field_var->val, 0);
+
+ kfree(field_var);
+}
+
+static void destroy_field_vars(struct hist_trigger_data *hist_data)
+{
+ unsigned int i;
+
+ for (i = 0; i < hist_data->n_field_vars; i++)
+ destroy_field_var(hist_data->field_vars[i]);
+}
+
+static void save_field_var(struct hist_trigger_data *hist_data,
+ struct field_var *field_var)
+{
+ hist_data->field_vars[hist_data->n_field_vars++] = field_var;
+
+ if (field_var->val->flags & HIST_FIELD_FL_STRING)
+ hist_data->n_field_var_str++;
+}
+
+
+static void destroy_synth_var_refs(struct hist_trigger_data *hist_data)
+{
+ unsigned int i;
+
+ for (i = 0; i < hist_data->n_synth_var_refs; i++)
+ destroy_hist_field(hist_data->synth_var_refs[i], 0);
+}
+
+static void save_synth_var_ref(struct hist_trigger_data *hist_data,
+ struct hist_field *var_ref)
+{
+ hist_data->synth_var_refs[hist_data->n_synth_var_refs++] = var_ref;
+
+ hist_data->var_refs[hist_data->n_var_refs] = var_ref;
+ var_ref->var_ref_idx = hist_data->n_var_refs++;
+}
+
+static int check_synth_field(struct synth_event *event,
+ struct hist_field *hist_field,
+ unsigned int field_pos)
+{
+ struct synth_field *field;
+
+ if (field_pos >= event->n_fields)
+ return -EINVAL;
+
+ field = event->fields[field_pos];
+
+ if (strcmp(field->type, hist_field->type) != 0)
+ return -EINVAL;
+
+ return 0;
+}
+
+static struct hist_field *
+onmatch_find_var(struct hist_trigger_data *hist_data, struct action_data *data,
+ char *system, char *event, char *var)
+{
+ struct hist_field *hist_field;
+
+ var++; /* skip '$' */
+
+ hist_field = find_target_event_var(hist_data, system, event, var);
+ if (!hist_field) {
+ if (!system) {
+ system = data->onmatch.match_event_system;
+ event = data->onmatch.match_event;
+ }
+
+ hist_field = find_event_var(hist_data, system, event, var);
+ }
+
+ if (!hist_field)
+ hist_err_event("onmatch: Couldn't find onmatch param: $", system, event, var);
+
+ return hist_field;
+}
+
+static struct hist_field *
+onmatch_create_field_var(struct hist_trigger_data *hist_data,
+ struct action_data *data, char *system,
+ char *event, char *var)
+{
+ struct hist_field *hist_field = NULL;
+ struct field_var *field_var;
+
+ /*
+ * First try to create a field var on the target event (the
+ * currently being defined). This will create a variable for
+ * unqualified fields on the target event, or if qualified,
+ * target fields that have qualified names matching the target.
+ */
+ field_var = create_target_field_var(hist_data, system, event, var);
+
+ if (field_var && !IS_ERR(field_var)) {
+ save_field_var(hist_data, field_var);
+ hist_field = field_var->var;
+ } else {
+ field_var = NULL;
+ /*
+ * If no explicit system.event is specfied, default to
+ * looking for fields on the onmatch(system.event.xxx)
+ * event.
+ */
+ if (!system) {
+ system = data->onmatch.match_event_system;
+ event = data->onmatch.match_event;
+ }
+
+ /*
+ * At this point, we're looking at a field on another
+ * event. Because we can't modify a hist trigger on
+ * another event to add a variable for a field, we need
+ * to create a new trigger on that event and create the
+ * variable at the same time.
+ */
+ hist_field = create_field_var_hist(hist_data, system, event, var);
+ if (IS_ERR(hist_field))
+ goto free;
+ }
+ out:
+ return hist_field;
+ free:
+ destroy_field_var(field_var);
+ hist_field = NULL;
+ goto out;
+}
+
+static int onmatch_create(struct hist_trigger_data *hist_data,
+ struct trace_event_file *file,
+ struct action_data *data)
+{
+ char *event_name, *param, *system = NULL;
+ struct hist_field *hist_field, *var_ref;
+ unsigned int i, var_ref_idx;
+ unsigned int field_pos = 0;
+ struct synth_event *event;
+ int ret = 0;
+
+ mutex_lock(&synth_event_mutex);
+ event = find_synth_event(data->onmatch.synth_event_name);
+ if (!event) {
+ hist_err("onmatch: Couldn't find synthetic event: ", data->onmatch.synth_event_name);
+ mutex_unlock(&synth_event_mutex);
+ return -EINVAL;
+ }
+ event->ref++;
+ mutex_unlock(&synth_event_mutex);
+
+ var_ref_idx = hist_data->n_var_refs;
+
+ for (i = 0; i < data->n_params; i++) {
+ char *p;
+
+ p = param = kstrdup(data->params[i], GFP_KERNEL);
+ if (!param) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ system = strsep(¶m, ".");
+ if (!param) {
+ param = (char *)system;
+ system = event_name = NULL;
+ } else {
+ event_name = strsep(¶m, ".");
+ if (!param) {
+ kfree(p);
+ ret = -EINVAL;
+ goto err;
+ }
+ }
+
+ if (param[0] == '$')
+ hist_field = onmatch_find_var(hist_data, data, system,
+ event_name, param);
+ else
+ hist_field = onmatch_create_field_var(hist_data, data,
+ system,
+ event_name,
+ param);
+
+ if (!hist_field) {
+ kfree(p);
+ ret = -EINVAL;
+ goto err;
+ }
+
+ if (check_synth_field(event, hist_field, field_pos) == 0) {
+ var_ref = create_var_ref(hist_field, system, event_name);
+ if (!var_ref) {
+ kfree(p);
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ save_synth_var_ref(hist_data, var_ref);
+ field_pos++;
+ kfree(p);
+ continue;
+ }
+
+ hist_err_event("onmatch: Param type doesn't match synthetic event field type: ",
+ system, event_name, param);
+ kfree(p);
+ ret = -EINVAL;
+ goto err;
+ }
+
+ if (field_pos != event->n_fields) {
+ hist_err("onmatch: Param count doesn't match synthetic event field count: ", event->name);
+ ret = -EINVAL;
+ goto err;
+ }
+
+ data->fn = action_trace;
+ data->onmatch.synth_event = event;
+ data->onmatch.var_ref_idx = var_ref_idx;
+ out:
+ return ret;
+ err:
+ mutex_lock(&synth_event_mutex);
+ event->ref--;
+ mutex_unlock(&synth_event_mutex);
+
+ goto out;
+}
+
+static struct action_data *onmatch_parse(struct trace_array *tr, char *str)
+{
+ char *match_event, *match_event_system;
+ char *synth_event_name, *params;
+ struct action_data *data;
+ int ret = -EINVAL;
+
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return ERR_PTR(-ENOMEM);
+
+ match_event = strsep(&str, ")");
+ if (!match_event || !str) {
+ hist_err("onmatch: Missing closing paren: ", match_event);
+ goto free;
+ }
+
+ match_event_system = strsep(&match_event, ".");
+ if (!match_event) {
+ hist_err("onmatch: Missing subsystem for match event: ", match_event_system);
+ goto free;
+ }
+
+ if (IS_ERR(event_file(tr, match_event_system, match_event))) {
+ hist_err_event("onmatch: Invalid subsystem or event name: ",
+ match_event_system, match_event, NULL);
+ goto free;
+ }
+
+ data->onmatch.match_event = kstrdup(match_event, GFP_KERNEL);
+ if (!data->onmatch.match_event) {
+ ret = -ENOMEM;
+ goto free;
+ }
+
+ data->onmatch.match_event_system = kstrdup(match_event_system, GFP_KERNEL);
+ if (!data->onmatch.match_event_system) {
+ ret = -ENOMEM;
+ goto free;
+ }
+
+ strsep(&str, ".");
+ if (!str) {
+ hist_err("onmatch: Missing . after onmatch(): ", str);
+ goto free;
+ }
+
+ synth_event_name = strsep(&str, "(");
+ if (!synth_event_name || !str) {
+ hist_err("onmatch: Missing opening paramlist paren: ", synth_event_name);
+ goto free;
+ }
+
+ data->onmatch.synth_event_name = kstrdup(synth_event_name, GFP_KERNEL);
+ if (!data->onmatch.synth_event_name) {
+ ret = -ENOMEM;
+ goto free;
+ }
+
+ params = strsep(&str, ")");
+ if (!params || !str || (str && strlen(str))) {
+ hist_err("onmatch: Missing closing paramlist paren: ", params);
+ goto free;
+ }
+
+ ret = parse_action_params(params, data);
+ if (ret)
+ goto free;
+ out:
+ return data;
+ free:
+ onmatch_destroy(data);
+ data = ERR_PTR(ret);
+ goto out;
+}
+
+static int create_hitcount_val(struct hist_trigger_data *hist_data)
+{
+ hist_data->fields[HITCOUNT_IDX] =
+ create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL);
+ if (!hist_data->fields[HITCOUNT_IDX])
+ return -ENOMEM;
+
+ hist_data->n_vals++;
+ hist_data->n_fields++;
+
+ 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 *var_name, char *field_str,
+ unsigned long flags)
+{
+ struct hist_field *hist_field;
+ int ret = 0;
+
+ hist_field = parse_expr(hist_data, file, field_str, flags, var_name, 0);
+ if (IS_ERR(hist_field)) {
+ ret = PTR_ERR(hist_field);
+ goto out;
+ }
+
+ hist_data->fields[val_idx] = hist_field;
+
+ ++hist_data->n_vals;
+ ++hist_data->n_fields;
+
+ if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX))
+ ret = -EINVAL;
+ out:
+ return ret;
+}
+
+static int create_val_field(struct hist_trigger_data *hist_data,
+ unsigned int val_idx,
+ struct trace_event_file *file,
+ char *field_str)
+{
+ if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX))
+ return -EINVAL;
+
+ return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0);
+}
+
+static int create_var_field(struct hist_trigger_data *hist_data,
+ unsigned int val_idx,
+ struct trace_event_file *file,
+ char *var_name, char *expr_str)
+{
+ unsigned long flags = 0;
+
+ if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX))
+ return -EINVAL;
+
+ if (find_var(hist_data, file, var_name) && !hist_data->remove) {
+ hist_err("Variable already defined: ", var_name);
+ return -EINVAL;
+ }
+
+ flags |= HIST_FIELD_FL_VAR;
+ hist_data->n_vars++;
+ if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX))
+ return -EINVAL;
+
+ return __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags);
+}
+
+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 = 1;
+ 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 hist_field *hist_field = NULL;
+
+ unsigned long flags = 0;
+ unsigned int key_size;
+ int ret = 0;
+
+ if (WARN_ON(key_idx >= HIST_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;
+ hist_field = create_hist_field(hist_data, NULL, flags, NULL);
+ } else {
+ hist_field = parse_expr(hist_data, file, field_str, flags,
+ NULL, 0);
+ if (IS_ERR(hist_field)) {
+ ret = PTR_ERR(hist_field);
+ goto out;
+ }
+
+ if (hist_field->flags & HIST_FIELD_FL_VAR_REF) {
+ hist_err("Using variable references as keys not supported: ", field_str);
+ destroy_hist_field(hist_field, 0);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ key_size = hist_field->size;
+ }
+
+ hist_data->fields[key_idx] = hist_field;
+
+ 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++;
+ hist_data->n_fields++;
+
+ 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_var_fields(struct hist_trigger_data *hist_data,
+ struct trace_event_file *file)
+{
+ unsigned int i, j = hist_data->n_vals;
+ int ret = 0;
+
+ unsigned int n_vars = hist_data->attrs->var_defs.n_vars;
+
+ for (i = 0; i < n_vars; i++) {
+ char *var_name = hist_data->attrs->var_defs.name[i];
+ char *expr = hist_data->attrs->var_defs.expr[i];
+
+ ret = create_var_field(hist_data, j++, file, var_name, expr);
+ if (ret)
+ goto out;
+ }
+ out:
+ return ret;
+}
+
+static void free_var_defs(struct hist_trigger_data *hist_data)
+{
+ unsigned int i;
+
+ for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) {
+ kfree(hist_data->attrs->var_defs.name[i]);
+ kfree(hist_data->attrs->var_defs.expr[i]);
+ }
+
+ hist_data->attrs->var_defs.n_vars = 0;
+}
+
+static int parse_var_defs(struct hist_trigger_data *hist_data)
+{
+ char *s, *str, *var_name, *field_str;
+ unsigned int i, j, n_vars = 0;
+ int ret = 0;
+
+ for (i = 0; i < hist_data->attrs->n_assignments; i++) {
+ str = hist_data->attrs->assignment_str[i];
+ for (j = 0; j < TRACING_MAP_VARS_MAX; j++) {
+ field_str = strsep(&str, ",");
+ if (!field_str)
+ break;
+
+ var_name = strsep(&field_str, "=");
+ if (!var_name || !field_str) {
+ hist_err("Malformed assignment: ", var_name);
+ ret = -EINVAL;
+ goto free;
+ }
+
+ if (n_vars == TRACING_MAP_VARS_MAX) {
+ hist_err("Too many variables defined: ", var_name);
+ ret = -EINVAL;
+ goto free;
+ }
+
+ s = kstrdup(var_name, GFP_KERNEL);
+ if (!s) {
+ ret = -ENOMEM;
+ goto free;
+ }
+ hist_data->attrs->var_defs.name[n_vars] = s;
+
+ s = kstrdup(field_str, GFP_KERNEL);
+ if (!s) {
+ kfree(hist_data->attrs->var_defs.name[n_vars]);
+ ret = -ENOMEM;
+ goto free;
+ }
+ hist_data->attrs->var_defs.expr[n_vars++] = s;
+
+ hist_data->attrs->var_defs.n_vars = n_vars;
+ }
+ }
+
+ return ret;
+ free:
+ free_var_defs(hist_data);
+
+ return ret;
+}
+
+static int create_hist_fields(struct hist_trigger_data *hist_data,
+ struct trace_event_file *file)
+{
+ int ret;
+
+ ret = parse_var_defs(hist_data);
+ if (ret)
+ goto out;
+
+ ret = create_val_fields(hist_data, file);
+ if (ret)
+ goto out;
+
+ ret = create_var_fields(hist_data, file);
+ if (ret)
+ goto out;
+
+ ret = create_key_fields(hist_data, file);
+ if (ret)
+ goto out;
+ out:
+ free_var_defs(hist_data);
+
+ 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 tracing_map_sort_key *sort_key;
+ int descending, ret = 0;
+ unsigned int i, j, k;
+
+ 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++) {
+ struct hist_field *hist_field;
+ char *field_str, *field_name;
+ const char *test_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, k = 1; j < hist_data->n_fields; j++) {
+ unsigned int idx;
+
+ hist_field = hist_data->fields[j];
+ if (hist_field->flags & HIST_FIELD_FL_VAR)
+ continue;
+
+ idx = k++;
+
+ test_name = hist_field_name(hist_field, 0);
+
+ if (strcmp(field_name, test_name) == 0) {
+ sort_key->field_idx = idx;
+ 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_actions(struct hist_trigger_data *hist_data)
+{
+ unsigned int i;
+
+ for (i = 0; i < hist_data->n_actions; i++) {
+ struct action_data *data = hist_data->actions[i];
+
+ if (data->fn == action_trace)
+ onmatch_destroy(data);
+ else if (data->fn == onmax_save)
+ onmax_destroy(data);
+ else
+ kfree(data);
+ }
+}
+
+static int parse_actions(struct hist_trigger_data *hist_data)
+{
+ struct trace_array *tr = hist_data->event_file->tr;
+ struct action_data *data;
+ unsigned int i;
+ int ret = 0;
+ char *str;
+
+ for (i = 0; i < hist_data->attrs->n_actions; i++) {
+ str = hist_data->attrs->action_str[i];
+
+ if (strncmp(str, "onmatch(", strlen("onmatch(")) == 0) {
+ char *action_str = str + strlen("onmatch(");
+
+ data = onmatch_parse(tr, action_str);
+ if (IS_ERR(data)) {
+ ret = PTR_ERR(data);
+ break;
+ }
+ data->fn = action_trace;
+ } else if (strncmp(str, "onmax(", strlen("onmax(")) == 0) {
+ char *action_str = str + strlen("onmax(");
+
+ data = onmax_parse(action_str);
+ if (IS_ERR(data)) {
+ ret = PTR_ERR(data);
+ break;
+ }
+ data->fn = onmax_save;
+ } else {
+ ret = -EINVAL;
+ break;
+ }
+
+ hist_data->actions[hist_data->n_actions++] = data;
+ }
+
+ return ret;
+}
+
+static int create_actions(struct hist_trigger_data *hist_data,
+ struct trace_event_file *file)
+{
+ struct action_data *data;
+ unsigned int i;
+ int ret = 0;
+
+ for (i = 0; i < hist_data->attrs->n_actions; i++) {
+ data = hist_data->actions[i];
+
+ if (data->fn == action_trace) {
+ ret = onmatch_create(hist_data, file, data);
+ if (ret)
+ return ret;
+ } else if (data->fn == onmax_save) {
+ ret = onmax_create(hist_data, data);
+ if (ret)
+ return ret;
+ }
+ }
+
+ return ret;
+}
+
+static void print_actions(struct seq_file *m,
+ struct hist_trigger_data *hist_data,
+ struct tracing_map_elt *elt)
+{
+ unsigned int i;
+
+ for (i = 0; i < hist_data->n_actions; i++) {
+ struct action_data *data = hist_data->actions[i];
+
+ if (data->fn == onmax_save)
+ onmax_print(m, hist_data, elt, data);
+ }
+}
+
+static void print_onmax_spec(struct seq_file *m,
+ struct hist_trigger_data *hist_data,
+ struct action_data *data)
+{
+ unsigned int i;
+
+ seq_puts(m, ":onmax(");
+ seq_printf(m, "%s", data->onmax.var_str);
+ seq_printf(m, ").%s(", data->onmax.fn_name);
+
+ for (i = 0; i < hist_data->n_max_vars; i++) {
+ seq_printf(m, "%s", hist_data->max_vars[i]->var->var.name);
+ if (i < hist_data->n_max_vars - 1)
+ seq_puts(m, ",");
+ }
+ seq_puts(m, ")");
+}
+
+static void print_onmatch_spec(struct seq_file *m,
+ struct hist_trigger_data *hist_data,
+ struct action_data *data)
+{
+ unsigned int i;
+
+ seq_printf(m, ":onmatch(%s.%s).", data->onmatch.match_event_system,
+ data->onmatch.match_event);
+
+ seq_printf(m, "%s(", data->onmatch.synth_event->name);
+
+ for (i = 0; i < data->n_params; i++) {
+ if (i)
+ seq_puts(m, ",");
+ seq_printf(m, "%s", data->params[i]);
+ }
+
+ seq_puts(m, ")");
+}
+
+static bool actions_match(struct hist_trigger_data *hist_data,
+ struct hist_trigger_data *hist_data_test)
+{
+ unsigned int i, j;
+
+ if (hist_data->n_actions != hist_data_test->n_actions)
+ return false;
+
+ for (i = 0; i < hist_data->n_actions; i++) {
+ struct action_data *data = hist_data->actions[i];
+ struct action_data *data_test = hist_data_test->actions[i];
+
+ if (data->fn != data_test->fn)
+ return false;
+
+ if (data->n_params != data_test->n_params)
+ return false;
+
+ for (j = 0; j < data->n_params; j++) {
+ if (strcmp(data->params[j], data_test->params[j]) != 0)
+ return false;
+ }
+
+ if (data->fn == action_trace) {
+ if (strcmp(data->onmatch.synth_event_name,
+ data_test->onmatch.synth_event_name) != 0)
+ return false;
+ if (strcmp(data->onmatch.match_event_system,
+ data_test->onmatch.match_event_system) != 0)
+ return false;
+ if (strcmp(data->onmatch.match_event,
+ data_test->onmatch.match_event) != 0)
+ return false;
+ } else if (data->fn == onmax_save) {
+ if (strcmp(data->onmax.var_str,
+ data_test->onmax.var_str) != 0)
+ return false;
+ if (strcmp(data->onmax.fn_name,
+ data_test->onmax.fn_name) != 0)
+ return false;
+ }
+ }
+
+ return true;
+}
+
+
+static void print_actions_spec(struct seq_file *m,
+ struct hist_trigger_data *hist_data)
+{
+ unsigned int i;
+
+ for (i = 0; i < hist_data->n_actions; i++) {
+ struct action_data *data = hist_data->actions[i];
+
+ if (data->fn == action_trace)
+ print_onmatch_spec(m, hist_data, data);
+ else if (data->fn == onmax_save)
+ print_onmax_spec(m, hist_data, data);
+ }
+}
+
+static void destroy_field_var_hists(struct hist_trigger_data *hist_data)
+{
+ unsigned int i;
+
+ for (i = 0; i < hist_data->n_field_var_hists; i++) {
+ kfree(hist_data->field_var_hists[i]->cmd);
+ kfree(hist_data->field_var_hists[i]);
+ }
+}
+
+static void destroy_hist_data(struct hist_trigger_data *hist_data)
+{
+ if (!hist_data)
+ return;
+
+ destroy_hist_trigger_attrs(hist_data->attrs);
+ destroy_hist_fields(hist_data);
+ tracing_map_destroy(hist_data->map);
+
+ destroy_actions(hist_data);
+ destroy_field_vars(hist_data);
+ destroy_field_var_hists(hist_data);
+ destroy_synth_var_refs(hist_data);
+
+ 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 = 0;
+
+ 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 (!field)
+ cmp_fn = tracing_map_cmp_num(hist_field->size,
+ hist_field->is_signed);
+ 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 if (!(hist_field->flags & HIST_FIELD_FL_VAR))
+ idx = tracing_map_add_sum_field(map);
+
+ if (idx < 0)
+ return idx;
+
+ if (hist_field->flags & HIST_FIELD_FL_VAR) {
+ idx = tracing_map_add_var(map);
+ if (idx < 0)
+ return idx;
+ hist_field->var.idx = idx;
+ hist_field->var.hist_data = hist_data;
+ }
+ }
+
+ return 0;
+}
+
+static struct hist_trigger_data *
+create_hist_data(unsigned int map_bits,
+ struct hist_trigger_attrs *attrs,
+ struct trace_event_file *file,
+ bool remove)
+{
+ 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;
+ hist_data->remove = remove;
+ hist_data->event_file = file;
+
+ ret = parse_actions(hist_data);
+ if (ret)
+ goto free;
+
+ ret = create_hist_fields(hist_data, file);
+ if (ret)
+ goto free;
+
+ ret = create_sort_keys(hist_data);
+ if (ret)
+ goto free;
+
+ map_ops = &hist_trigger_elt_data_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;
+ 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 ring_buffer_event *rbe,
+ u64 *var_ref_vals)
+{
+ struct hist_elt_data *elt_data;
+ struct hist_field *hist_field;
+ unsigned int i, var_idx;
+ u64 hist_val;
+
+ elt_data = elt->private_data;
+ elt_data->var_ref_vals = var_ref_vals;
+
+ for_each_hist_val_field(i, hist_data) {
+ hist_field = hist_data->fields[i];
+ hist_val = hist_field->fn(hist_field, elt, rbe, rec);
+ if (hist_field->flags & HIST_FIELD_FL_VAR) {
+ var_idx = hist_field->var.idx;
+ tracing_map_set_var(elt, var_idx, hist_val);
+ continue;
+ }
+ tracing_map_update_sum(elt, i, hist_val);
+ }
+
+ for_each_hist_key_field(i, hist_data) {
+ hist_field = hist_data->fields[i];
+ if (hist_field->flags & HIST_FIELD_FL_VAR) {
+ hist_val = hist_field->fn(hist_field, elt, rbe, rec);
+ var_idx = hist_field->var.idx;
+ tracing_map_set_var(elt, var_idx, hist_val);
+ }
+ }
+
+ update_field_vars(hist_data, elt, rbe, rec);
+}
+
+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
+hist_trigger_actions(struct hist_trigger_data *hist_data,
+ struct tracing_map_elt *elt, void *rec,
+ struct ring_buffer_event *rbe, u64 *var_ref_vals)
+{
+ struct action_data *data;
+ unsigned int i;
+
+ for (i = 0; i < hist_data->n_actions; i++) {
+ data = hist_data->actions[i];
+ data->fn(hist_data, elt, rec, rbe, data, var_ref_vals);
+ }
+}
+
+static void event_hist_trigger(struct event_trigger_data *data, void *rec,
+ struct ring_buffer_event *rbe)
+{
+ struct hist_trigger_data *hist_data = data->private_data;
+ bool use_compound_key = (hist_data->n_keys > 1);
+ unsigned long entries[HIST_STACKTRACE_DEPTH];
+ u64 var_ref_vals[TRACING_MAP_VARS_MAX];
+ char compound_key[HIST_KEY_SIZE_MAX];
+ struct tracing_map_elt *elt = NULL;
+ struct stack_trace stacktrace;
+ struct hist_field *key_field;
+ 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, elt, rbe, 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;
+
+ if (hist_data->n_var_refs &&
+ !resolve_var_refs(hist_data, key, var_ref_vals, false))
+ return;
+
+ elt = tracing_map_insert(hist_data->map, key);
+ if (!elt)
+ return;
+
+ hist_trigger_elt_update(hist_data, elt, rec, rbe, var_ref_vals);
+
+ if (resolve_var_refs(hist_data, key, var_ref_vals, true))
+ hist_trigger_actions(hist_data, elt, rec, rbe, var_ref_vals);
+}
+
+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;
+ const char *field_name;
+ 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, ", ");
+
+ field_name = hist_field_name(key_field, 0);
+
+ if (key_field->flags & HIST_FIELD_FL_HEX) {
+ uval = *(u64 *)(key + key_field->offset);
+ seq_printf(m, "%s: %llx", 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", 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", field_name,
+ uval, str);
+ } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
+ struct hist_elt_data *elt_data = elt->private_data;
+ char *comm;
+
+ if (WARN_ON_ONCE(!elt_data))
+ return;
+
+ comm = elt_data->comm;
+
+ uval = *(u64 *)(key + key_field->offset);
+ seq_printf(m, "%s: %-16s[%10llu]", 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]", 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", field_name,
+ *(u64 *)(key + key_field->offset));
+ } else if (key_field->flags & HIST_FIELD_FL_STRING) {
+ seq_printf(m, "%s: %-50s", field_name,
+ (char *)(key + key_field->offset));
+ } else {
+ uval = *(u64 *)(key + key_field->offset);
+ seq_printf(m, "%s: %10llu", 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++) {
+ field_name = hist_field_name(hist_data->fields[i], 0);
+
+ if (hist_data->fields[i]->flags & HIST_FIELD_FL_VAR ||
+ hist_data->fields[i]->flags & HIST_FIELD_FL_EXPR)
+ continue;
+
+ if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) {
+ seq_printf(m, " %s: %10llx", field_name,
+ tracing_map_read_sum(elt, i));
+ } else {
+ seq_printf(m, " %s: %10llu", field_name,
+ tracing_map_read_sum(elt, i));
+ }
+ }
+
+ print_actions(m, hist_data, elt);
+
+ 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;
+
+ 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)
+ 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++);
+ }
+
+ if (have_hist_err()) {
+ seq_printf(m, "\nERROR: %s\n", hist_err_str);
+ seq_printf(m, " Last command: %s\n", last_hist_cmd);
+ }
+
+ 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 void hist_field_print(struct seq_file *m, struct hist_field *hist_field)
+{
+ const char *field_name = hist_field_name(hist_field, 0);
+
+ if (hist_field->var.name)
+ seq_printf(m, "%s=", hist_field->var.name);
+
+ if (hist_field->flags & HIST_FIELD_FL_CPU)
+ seq_puts(m, "cpu");
+ else if (field_name) {
+ if (hist_field->flags & HIST_FIELD_FL_VAR_REF ||
+ hist_field->flags & HIST_FIELD_FL_ALIAS)
+ seq_putc(m, '$');
+ seq_printf(m, "%s", field_name);
+ } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP)
+ seq_puts(m, "common_timestamp");
+
+ if (hist_field->flags) {
+ if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) &&
+ !(hist_field->flags & HIST_FIELD_FL_EXPR)) {
+ const char *flags = get_hist_field_flags(hist_field);
+
+ if (flags)
+ seq_printf(m, ".%s", flags);
+ }
+ }
+}
+
+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 *field;
+ bool have_var = false;
+ 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) {
+ field = hist_data->fields[i];
+
+ if (i > hist_data->n_vals)
+ seq_puts(m, ",");
+
+ if (field->flags & HIST_FIELD_FL_STACKTRACE)
+ seq_puts(m, "stacktrace");
+ else
+ hist_field_print(m, field);
+ }
+
+ seq_puts(m, ":vals=");
+
+ for_each_hist_val_field(i, hist_data) {
+ field = hist_data->fields[i];
+ if (field->flags & HIST_FIELD_FL_VAR) {
+ have_var = true;
+ continue;
+ }
+
+ if (i == HITCOUNT_IDX)
+ seq_puts(m, "hitcount");
+ else {
+ seq_puts(m, ",");
+ hist_field_print(m, field);
+ }
+ }
+
+ if (have_var) {
+ unsigned int n = 0;
+
+ seq_puts(m, ":");
+
+ for_each_hist_val_field(i, hist_data) {
+ field = hist_data->fields[i];
+
+ if (field->flags & HIST_FIELD_FL_VAR) {
+ if (n++)
+ seq_puts(m, ",");
+ hist_field_print(m, field);
+ }
+ }
+ }
+
+ seq_puts(m, ":sort=");
+
+ for (i = 0; i < hist_data->n_sort_keys; i++) {
+ struct tracing_map_sort_key *sort_key;
+ unsigned int idx, first_key_idx;
+
+ /* skip VAR vals */
+ first_key_idx = hist_data->n_vals - hist_data->n_vars;
+
+ sort_key = &hist_data->sort_keys[i];
+ idx = sort_key->field_idx;
+
+ if (WARN_ON(idx >= HIST_FIELDS_MAX))
+ return -EINVAL;
+
+ if (i > 0)
+ seq_puts(m, ",");
+
+ if (idx == HITCOUNT_IDX)
+ seq_puts(m, "hitcount");
+ else {
+ if (idx >= first_key_idx)
+ idx += hist_data->n_vars;
+ 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 (hist_data->enable_timestamps)
+ seq_printf(m, ":clock=%s", hist_data->attrs->clock);
+
+ print_actions_spec(m, hist_data);
+
+ 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 unregister_field_var_hists(struct hist_trigger_data *hist_data)
+{
+ struct trace_event_file *file;
+ unsigned int i;
+ char *cmd;
+ int ret;
+
+ for (i = 0; i < hist_data->n_field_var_hists; i++) {
+ file = hist_data->field_var_hists[i]->hist_data->event_file;
+ cmd = hist_data->field_var_hists[i]->cmd;
+ ret = event_hist_trigger_func(&trigger_hist_cmd, file,
+ "!hist", "hist", cmd);
+ }
+}
+
+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);
+
+ remove_hist_vars(hist_data);
+
+ unregister_field_var_hists(hist_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);
+
+ tracepoint_synchronize_unregister();
+
+ 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;
+ if (key_field->size != key_field_test->size)
+ return false;
+ if (key_field->is_signed != key_field_test->is_signed)
+ return false;
+ if (!!key_field->var.name != !!key_field_test->var.name)
+ return false;
+ if (key_field->var.name &&
+ strcmp(key_field->var.name, key_field_test->var.name) != 0)
+ 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;
+
+ if (!actions_match(hist_data, hist_data_test))
+ 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)) {
+ hist_err("Named hist trigger doesn't match existing named trigger (includes variables): ", hist_data->attrs->name);
+ 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 {
+ hist_err("Hist trigger already exists", NULL);
+ ret = -EEXIST;
+ }
+ goto out;
+ }
+ }
+ new:
+ if (hist_data->attrs->cont || hist_data->attrs->clear) {
+ hist_err("Can't clear or continue a nonexistent hist trigger", NULL);
+ ret = -ENOENT;
+ goto out;
+ }
+
+ if (hist_data->attrs->pause)
+ data->paused = true;
+
+ if (named_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;
+ }
+
+ if (hist_data->enable_timestamps) {
+ char *clock = hist_data->attrs->clock;
+
+ ret = tracing_set_clock(file->tr, hist_data->attrs->clock);
+ if (ret) {
+ hist_err("Couldn't set trace_clock: ", clock);
+ goto out;
+ }
+
+ tracing_set_time_stamp_abs(file->tr, true);
+ }
+
+ if (named_data)
+ destroy_hist_data(hist_data);
+
+ ret++;
+ out:
+ return ret;
+}
+
+static int hist_trigger_enable(struct event_trigger_data *data,
+ struct trace_event_file *file)
+{
+ int ret = 0;
+
+ list_add_tail_rcu(&data->list, &file->triggers);
+
+ update_cond_flag(file);
+
+ if (trace_event_trigger_enable_disable(file, 1) < 0) {
+ list_del_rcu(&data->list);
+ update_cond_flag(file);
+ ret--;
+ }
+
+ return ret;
+}
+
+static bool have_hist_trigger_match(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 match = 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)) {
+ match = true;
+ break;
+ }
+ }
+ }
+
+ return match;
+}
+
+static bool hist_trigger_check_refs(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;
+
+ 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;
+ hist_data = test->private_data;
+ if (check_var_refs(hist_data))
+ return true;
+ break;
+ }
+ }
+
+ return false;
+}
+
+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);
+
+ if (hist_data->enable_timestamps) {
+ if (!hist_data->remove || unregistered)
+ tracing_set_time_stamp_abs(file->tr, false);
+ }
+}
+
+static bool hist_file_check_refs(struct trace_event_file *file)
+{
+ struct hist_trigger_data *hist_data;
+ struct event_trigger_data *test;
+
+ list_for_each_entry_rcu(test, &file->triggers, list) {
+ if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
+ hist_data = test->private_data;
+ if (check_var_refs(hist_data))
+ return true;
+ }
+ }
+
+ return false;
+}
+
+static void hist_unreg_all(struct trace_event_file *file)
+{
+ struct event_trigger_data *test, *n;
+ struct hist_trigger_data *hist_data;
+ struct synth_event *se;
+ const char *se_name;
+
+ if (hist_file_check_refs(file))
+ return;
+
+ list_for_each_entry_safe(test, n, &file->triggers, list) {
+ if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
+ hist_data = test->private_data;
+ list_del_rcu(&test->list);
+ trace_event_trigger_enable_disable(file, 0);
+
+ mutex_lock(&synth_event_mutex);
+ se_name = trace_event_name(file->event_call);
+ se = find_synth_event(se_name);
+ if (se)
+ se->ref--;
+ mutex_unlock(&synth_event_mutex);
+
+ update_cond_flag(file);
+ if (hist_data->enable_timestamps)
+ tracing_set_time_stamp_abs(file->tr, false);
+ 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;
+ struct synth_event *se;
+ const char *se_name;
+ bool remove = false;
+ char *trigger, *p;
+ int ret = 0;
+
+ if (glob && strlen(glob)) {
+ last_cmd_set(param);
+ hist_err_clear();
+ }
+
+ if (!param)
+ return -EINVAL;
+
+ if (glob[0] == '!')
+ remove = true;
+
+ /*
+ * separate the trigger from the filter (k:v [if filter])
+ * allowing for whitespace in the trigger
+ */
+ p = trigger = param;
+ do {
+ p = strstr(p, "if");
+ if (!p)
+ break;
+ if (p == param)
+ return -EINVAL;
+ if (*(p - 1) != ' ' && *(p - 1) != '\t') {
+ p++;
+ continue;
+ }
+ if (p >= param + strlen(param) - strlen("if") - 1)
+ return -EINVAL;
+ if (*(p + strlen("if")) != ' ' && *(p + strlen("if")) != '\t') {
+ p++;
+ continue;
+ }
+ break;
+ } while (p);
+
+ if (!p)
+ param = NULL;
+ else {
+ *(p - 1) = '\0';
+ param = strstrip(p);
+ trigger = strstrip(trigger);
+ }
+
+ 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, remove);
+ if (IS_ERR(hist_data)) {
+ destroy_hist_trigger_attrs(attrs);
+ return PTR_ERR(hist_data);
+ }
+
+ trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger);
+
+ trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL);
+ if (!trigger_data) {
+ ret = -ENOMEM;
+ 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 (remove) {
+ if (!have_hist_trigger_match(trigger_data, file))
+ goto out_free;
+
+ if (hist_trigger_check_refs(trigger_data, file)) {
+ ret = -EBUSY;
+ goto out_free;
+ }
+
+ cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file);
+
+ mutex_lock(&synth_event_mutex);
+ se_name = trace_event_name(file->event_call);
+ se = find_synth_event(se_name);
+ if (se)
+ se->ref--;
+ mutex_unlock(&synth_event_mutex);
+
+ 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;
+
+ if (get_named_trigger_data(trigger_data))
+ goto enable;
+
+ if (has_hist_vars(hist_data))
+ save_hist_vars(hist_data);
+
+ ret = create_actions(hist_data, file);
+ if (ret)
+ goto out_unreg;
+
+ ret = tracing_map_init(hist_data->map);
+ if (ret)
+ goto out_unreg;
+enable:
+ ret = hist_trigger_enable(trigger_data, file);
+ if (ret)
+ goto out_unreg;
+
+ mutex_lock(&synth_event_mutex);
+ se_name = trace_event_name(file->event_call);
+ se = find_synth_event(se_name);
+ if (se)
+ se->ref++;
+ mutex_unlock(&synth_event_mutex);
+
+ /* Just return zero, not the number of registered triggers */
+ ret = 0;
+ out:
+ if (ret == 0)
+ hist_err_clear();
+
+ return ret;
+ out_unreg:
+ cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file);
+ out_free:
+ if (cmd_ops->set_filter)
+ cmd_ops->set_filter(NULL, trigger_data, NULL);
+
+ remove_hist_vars(hist_data);
+
+ 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 ring_buffer_event *event)
+{
+ 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,
+ struct ring_buffer_event *event)
+{
+ if (!data->count)
+ return;
+
+ if (data->count != -1)
+ (data->count)--;
+
+ hist_enable_trigger(data, rec, event);
+}
+
+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;
+}
+
+static __init int trace_events_hist_init(void)
+{
+ struct dentry *entry = NULL;
+ struct dentry *d_tracer;
+ int err = 0;
+
+ d_tracer = tracing_init_dentry();
+ if (IS_ERR(d_tracer)) {
+ err = PTR_ERR(d_tracer);
+ goto err;
+ }
+
+ entry = tracefs_create_file("synthetic_events", 0644, d_tracer,
+ NULL, &synth_events_fops);
+ if (!entry) {
+ err = -ENODEV;
+ goto err;
+ }
+
+ return err;
+ err:
+ pr_warn("Could not create tracefs 'synthetic_events' entry\n");
+
+ return err;
+}
+
+fs_initcall(trace_events_hist_init);