}
EXPORT_SYMBOL_GPL(unregister_ftrace_function);
- static bool is_permanent_ops_registered(void)
- {
- struct ftrace_ops *op;
-
- do_for_each_ftrace_op(op, ftrace_ops_list) {
- if (op->flags & FTRACE_OPS_FL_PERMANENT)
- return true;
- } while_for_each_ftrace_op(op);
-
- return false;
- }
-
- int
- ftrace_enable_sysctl(struct ctl_table *table, int write,
- void *buffer, size_t *lenp, loff_t *ppos)
- {
- int ret = -ENODEV;
-
- mutex_lock(&ftrace_lock);
-
- if (unlikely(ftrace_disabled))
- goto out;
-
- ret = proc_dointvec(table, write, buffer, lenp, ppos);
-
- if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled))
- goto out;
-
- if (ftrace_enabled) {
-
- /* we are starting ftrace again */
- if (rcu_dereference_protected(ftrace_ops_list,
- lockdep_is_held(&ftrace_lock)) != &ftrace_list_end)
- update_ftrace_function();
-
- ftrace_startup_sysctl();
-
- } else {
- if (is_permanent_ops_registered()) {
- ftrace_enabled = true;
- ret = -EBUSY;
- goto out;
- }
-
- /* stopping ftrace calls (just send to ftrace_stub) */
- ftrace_trace_function = ftrace_stub;
-
- ftrace_shutdown_sysctl();
- }
-
- last_ftrace_enabled = !!ftrace_enabled;
- out:
- mutex_unlock(&ftrace_lock);
- return ret;
- }
-
+static int symbols_cmp(const void *a, const void *b)
+{
+ const char **str_a = (const char **) a;
+ const char **str_b = (const char **) b;
+
+ return strcmp(*str_a, *str_b);
+}
+
+struct kallsyms_data {
+ unsigned long *addrs;
+ const char **syms;
+ size_t cnt;
+ size_t found;
+};
+
+static int kallsyms_callback(void *data, const char *name,
+ struct module *mod, unsigned long addr)
+{
+ struct kallsyms_data *args = data;
+
+ if (!bsearch(&name, args->syms, args->cnt, sizeof(*args->syms), symbols_cmp))
+ return 0;
+
+ addr = ftrace_location(addr);
+ if (!addr)
+ return 0;
+
+ args->addrs[args->found++] = addr;
+ return args->found == args->cnt ? 1 : 0;
+}
+
+/**
+ * ftrace_lookup_symbols - Lookup addresses for array of symbols
+ *
+ * @sorted_syms: array of symbols pointers symbols to resolve,
+ * must be alphabetically sorted
+ * @cnt: number of symbols/addresses in @syms/@addrs arrays
+ * @addrs: array for storing resulting addresses
+ *
+ * This function looks up addresses for array of symbols provided in
+ * @syms array (must be alphabetically sorted) and stores them in
+ * @addrs array, which needs to be big enough to store at least @cnt
+ * addresses.
+ *
+ * This function returns 0 if all provided symbols are found,
+ * -ESRCH otherwise.
+ */
+int ftrace_lookup_symbols(const char **sorted_syms, size_t cnt, unsigned long *addrs)
+{
+ struct kallsyms_data args;
+ int err;
+
+ args.addrs = addrs;
+ args.syms = sorted_syms;
+ args.cnt = cnt;
+ args.found = 0;
+ err = kallsyms_on_each_symbol(kallsyms_callback, &args);
+ if (err < 0)
+ return err;
+ return args.found == args.cnt ? 0 : -ESRCH;
+}
++
+ #ifdef CONFIG_SYSCTL
+
+ #ifdef CONFIG_DYNAMIC_FTRACE
+ static void ftrace_startup_sysctl(void)
+ {
+ int command;
+
+ if (unlikely(ftrace_disabled))
+ return;
+
+ /* Force update next time */
+ saved_ftrace_func = NULL;
+ /* ftrace_start_up is true if we want ftrace running */
+ if (ftrace_start_up) {
+ command = FTRACE_UPDATE_CALLS;
+ if (ftrace_graph_active)
+ command |= FTRACE_START_FUNC_RET;
+ ftrace_startup_enable(command);
+ }
+ }
+
+ static void ftrace_shutdown_sysctl(void)
+ {
+ int command;
+
+ if (unlikely(ftrace_disabled))
+ return;
+
+ /* ftrace_start_up is true if ftrace is running */
+ if (ftrace_start_up) {
+ command = FTRACE_DISABLE_CALLS;
+ if (ftrace_graph_active)
+ command |= FTRACE_STOP_FUNC_RET;
+ ftrace_run_update_code(command);
+ }
+ }
+ #else
+ # define ftrace_startup_sysctl() do { } while (0)
+ # define ftrace_shutdown_sysctl() do { } while (0)
+ #endif /* CONFIG_DYNAMIC_FTRACE */
+
+ static bool is_permanent_ops_registered(void)
+ {
+ struct ftrace_ops *op;
+
+ do_for_each_ftrace_op(op, ftrace_ops_list) {
+ if (op->flags & FTRACE_OPS_FL_PERMANENT)
+ return true;
+ } while_for_each_ftrace_op(op);
+
+ return false;
+ }
+
+ static int
+ ftrace_enable_sysctl(struct ctl_table *table, int write,
+ void *buffer, size_t *lenp, loff_t *ppos)
+ {
+ int ret = -ENODEV;
+
+ mutex_lock(&ftrace_lock);
+
+ if (unlikely(ftrace_disabled))
+ goto out;
+
+ ret = proc_dointvec(table, write, buffer, lenp, ppos);
+
+ if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled))
+ goto out;
+
+ if (ftrace_enabled) {
+
+ /* we are starting ftrace again */
+ if (rcu_dereference_protected(ftrace_ops_list,
+ lockdep_is_held(&ftrace_lock)) != &ftrace_list_end)
+ update_ftrace_function();
+
+ ftrace_startup_sysctl();
+
+ } else {
+ if (is_permanent_ops_registered()) {
+ ftrace_enabled = true;
+ ret = -EBUSY;
+ goto out;
+ }
+
+ /* stopping ftrace calls (just send to ftrace_stub) */
+ ftrace_trace_function = ftrace_stub;
+
+ ftrace_shutdown_sysctl();
+ }
+
+ last_ftrace_enabled = !!ftrace_enabled;
+ out:
+ mutex_unlock(&ftrace_lock);
+ return ret;
+ }
+
+ static struct ctl_table ftrace_sysctls[] = {
+ {
+ .procname = "ftrace_enabled",
+ .data = &ftrace_enabled,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = ftrace_enable_sysctl,
+ },
+ {}
+ };
+
+ static int __init ftrace_sysctl_init(void)
+ {
+ register_sysctl_init("kernel", ftrace_sysctls);
+ return 0;
+ }
+ late_initcall(ftrace_sysctl_init);
+ #endif