// SPDX-License-Identifier: GPL-2.0 /* * trace_events_hist - trace event hist triggers * * Copyright (C) 2015 Tom Zanussi */ #include #include #include #include #include #include #include #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 ref; 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; if (strcmp(type, "gfp_t") == 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 { struct synth_field *field = event->fields[i]; u64 val = var_ref_vals[var_ref_idx + i]; switch (field->size) { case 1: *(u8 *)&entry->fields[n_u64] = (u8)val; break; case 2: *(u16 *)&entry->fields[n_u64] = (u16)val; break; case 4: *(u32 *)&entry->fields[n_u64] = (u32)val; break; default: entry->fields[n_u64] = val; break; } 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_nolock(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_nolock(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 { if (!find_synth_event(event->name)) list_add(&event->list, &synth_event_list); else free_synth_event(event); } } 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(&event_mutex); mutex_lock(&synth_event_mutex); /* * Argument syntax: * - Add synthetic event: field[;field] ... * - Remove synthetic event: ! 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: 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); } } mutex_unlock(&synth_event_mutex); mutex_unlock(&event_mutex); return ret; err: mutex_unlock(&synth_event_mutex); mutex_unlock(&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 synth_event *event, *e; int ret = 0; mutex_lock(&event_mutex); 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_for_each_entry_safe(event, e, &synth_event_list, list) { list_del(&event->list); ret = unregister_synth_event(event); add_or_delete_synth_event(event, !ret); } mutex_unlock(&synth_event_mutex); mutex_unlock(&event_mutex); 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; } /** * check_field_for_var_ref - Check if a VAR_REF field references a variable * @hist_field: The VAR_REF field to check * @var_data: The hist trigger that owns the variable * @var_idx: The trigger variable identifier * * Check the given VAR_REF field to see whether or not it references * the given variable associated with the given trigger. * * Return: The VAR_REF field if it does reference the variable, NULL if not */ 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; } /** * find_var_ref - Check if a trigger has a reference to a trigger variable * @hist_data: The hist trigger that might have a reference to the variable * @var_data: The hist trigger that owns the variable * @var_idx: The trigger variable identifier * * Check the list of var_refs[] on the first hist trigger to see * whether any of them are references to the variable on the second * trigger. * * Return: The VAR_REF field referencing the variable if so, NULL if not */ 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; } /** * find_any_var_ref - Check if there is a reference to a given trigger variable * @hist_data: The hist trigger * @var_idx: The trigger variable identifier * * Check to see whether the given variable is currently referenced by * any other trigger. * * The trigger the variable is defined on is explicitly excluded - the * assumption being that a self-reference doesn't prevent a trigger * from being removed. * * Return: The VAR_REF field referencing the variable if so, NULL if not */ 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; } /** * check_var_refs - Check if there is a reference to any of trigger's variables * @hist_data: The hist trigger * * A trigger can define one or more variables. If any one of them is * currently referenced by any other trigger, this function will * determine that. * Typically used to determine whether or not a trigger can be removed * - if there are any references to a trigger's variables, it cannot. * * Return: True if there is a reference to any of trigger's variables */ 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; lockdep_assert_held(&event_mutex); hist_field = find_var_field(hist_data, var_name); if (hist_field) return hist_field; list_for_each_entry(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; lockdep_assert_held(&event_mutex); list_for_each_entry(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; if (WARN_ON_ONCE(!elt)) return var_val; 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 (WARN_ON_ONCE(!field)) return 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 = "common_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, ""); return; } if (WARN_ON_ONCE(task->pid < 0)) { strcpy(comm, ""); 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 '-': /* * Unfortunately, the modifier ".sym-offset" * can confuse things. */ if (op - str >= 4 && !strncmp(op - 4, ".sym-offset", 11)) return FIELD_OP_NONE; 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 get_hist_field(struct hist_field *hist_field) { hist_field->ref++; } static void __destroy_hist_field(struct hist_field *hist_field) { if (--hist_field->ref > 1) return; kfree(hist_field->var.name); kfree(hist_field->name); kfree(hist_field->type); kfree(hist_field); } static void destroy_hist_field(struct hist_field *hist_field, unsigned int level) { unsigned int i; if (level > 3) return; if (!hist_field) return; if (hist_field->flags & HIST_FIELD_FL_VAR_REF) return; /* var refs will be destroyed separately */ for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) destroy_hist_field(hist_field->operands[i], level + 1); __destroy_hist_field(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->ref = 1; 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); if (!hist_field->operands[0]) goto free; 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; /* Pointers to strings are just pointers and dangerous to dereference */ if (is_string_field(field) && (field->filter_type != FILTER_PTR_STRING)) { 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; } } for (i = 0; i < hist_data->n_var_refs; i++) { WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF)); __destroy_hist_field(hist_data->var_refs[i]); hist_data->var_refs[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); ref_field->system = NULL; kfree(ref_field->event_name); ref_field->event_name = NULL; kfree(ref_field->name); ref_field->name = NULL; goto out; } /** * create_var_ref - Create a variable reference and attach it to trigger * @hist_data: The trigger that will be referencing the variable * @var_field: The VAR field to create a reference to * @system: The optional system string * @event_name: The optional event_name string * * Given a variable hist_field, create a VAR_REF hist_field that * represents a reference to it. * * This function also adds the reference to the trigger that * now references the variable. * * Return: The VAR_REF field if successful, NULL if not */ static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data, struct hist_field *var_field, char *system, char *event_name) { unsigned long flags = HIST_FIELD_FL_VAR_REF; struct hist_field *ref_field; int i; /* Check if the variable already exists */ for (i = 0; i < hist_data->n_var_refs; i++) { ref_field = hist_data->var_refs[i]; if (ref_field->var.idx == var_field->var.idx && ref_field->var.hist_data == var_field->hist_data) { get_hist_field(ref_field); return 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; } hist_data->var_refs[hist_data->n_var_refs] = ref_field; ref_field->var_ref_idx = hist_data->n_var_refs++; } 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(hist_data, 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, "common_cpu") == 0) *flags |= HIST_FIELD_FL_CPU; else { field = trace_find_event_field(file->event_call, field_name); if (!field || !field->size) { /* * For backward compatibility, if field_name * was "cpu", then we treat this the same as * common_cpu. This also works for "CPU". */ if (field && field->filter_type == FILTER_CPU) { *flags |= HIST_FIELD_FL_CPU; } else { 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; } alias->var_ref_idx = var_ref->var_ref_idx; 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) { 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; } if (operand1->flags & HIST_FIELD_FL_STRING) { /* String type can not be the operand of unary operator. */ destroy_hist_field(operand1, 0); ret = -EINVAL; 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; } if (operand1->flags & HIST_FIELD_FL_STRING) { ret = -EINVAL; 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; } if (operand2->flags & HIST_FIELD_FL_STRING) { ret = -EINVAL; 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; /* The operand sizes should be the same, so just pick one */ expr->size = operand1->size; 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; lockdep_assert_held(&event_mutex); list_for_each_entry(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; lockdep_assert_held(&event_mutex); n_keys = target_hist_data->n_fields - target_hist_data->n_vals; list_for_each_entry(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 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; } ref_field = create_var_ref(hist_data, var_field, NULL, NULL); if (!ref_field) return -ENOMEM; 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; } 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; } if (!event) goto free; /* * 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_data, 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]); hist_data->attrs->var_defs.name[n_vars] = NULL; 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 || hist_field->flags & HIST_FIELD_FL_CPU) 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_STATIC_STRING) size = field->size; /* ensure NULL-termination */ if (size > key_field->size - 1) size = key_field->size - 1; strncpy(compound_key + key_field->offset, (char *)key, size); } else 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(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, "common_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; lockdep_assert_held(&event_mutex); list_for_each_entry(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; lockdep_assert_held(&event_mutex); if (hist_data->attrs->name) named_data = find_named_trigger(hist_data->attrs->name); list_for_each_entry(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; lockdep_assert_held(&event_mutex); if (hist_data->attrs->name) named_data = find_named_trigger(hist_data->attrs->name); list_for_each_entry(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; lockdep_assert_held(&event_mutex); if (hist_data->attrs->name) named_data = find_named_trigger(hist_data->attrs->name); list_for_each_entry(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; lockdep_assert_held(&event_mutex); list_for_each_entry(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 && glob[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);