Merge branch 'linus' into tracing/core
[firefly-linux-kernel-4.4.55.git] / kernel / trace / trace_events.c
index e75276a49cf5cfa2fb968609602621fa8e5a5da3..56c260b83a9cc8a4fa76a44a387cbc68691ae2ff 100644 (file)
 #include <linux/ctype.h>
 #include <linux/delay.h>
 
+#include <asm/setup.h>
+
 #include "trace_output.h"
 
+#undef TRACE_SYSTEM
 #define TRACE_SYSTEM "TRACE_SYSTEM"
 
 DEFINE_MUTEX(event_mutex);
 
 LIST_HEAD(ftrace_events);
 
-int trace_define_field(struct ftrace_event_call *call, char *type,
-                      char *name, int offset, int size, int is_signed)
+int trace_define_field(struct ftrace_event_call *call, const char *type,
+                      const char *name, int offset, int size, int is_signed,
+                      int filter_type)
 {
        struct ftrace_event_field *field;
 
@@ -42,9 +46,15 @@ int trace_define_field(struct ftrace_event_call *call, char *type,
        if (!field->type)
                goto err;
 
+       if (filter_type == FILTER_OTHER)
+               field->filter_type = filter_assign_type(type);
+       else
+               field->filter_type = filter_type;
+
        field->offset = offset;
        field->size = size;
        field->is_signed = is_signed;
+
        list_add(&field->link, &call->fields);
 
        return 0;
@@ -60,6 +70,29 @@ err:
 }
 EXPORT_SYMBOL_GPL(trace_define_field);
 
+#define __common_field(type, item)                                     \
+       ret = trace_define_field(call, #type, "common_" #item,          \
+                                offsetof(typeof(ent), item),           \
+                                sizeof(ent.item),                      \
+                                is_signed_type(type), FILTER_OTHER);   \
+       if (ret)                                                        \
+               return ret;
+
+int trace_define_common_fields(struct ftrace_event_call *call)
+{
+       int ret;
+       struct trace_entry ent;
+
+       __common_field(unsigned short, type);
+       __common_field(unsigned char, flags);
+       __common_field(unsigned char, preempt_count);
+       __common_field(int, pid);
+       __common_field(int, lock_depth);
+
+       return ret;
+}
+EXPORT_SYMBOL_GPL(trace_define_common_fields);
+
 #ifdef CONFIG_MODULES
 
 static void trace_destroy_fields(struct ftrace_event_call *call)
@@ -84,14 +117,14 @@ static void ftrace_event_enable_disable(struct ftrace_event_call *call,
                if (call->enabled) {
                        call->enabled = 0;
                        tracing_stop_cmdline_record();
-                       call->unregfunc();
+                       call->unregfunc(call->data);
                }
                break;
        case 1:
                if (!call->enabled) {
                        call->enabled = 1;
                        tracing_start_cmdline_record();
-                       call->regfunc();
+                       call->regfunc(call->data);
                }
                break;
        }
@@ -198,11 +231,9 @@ static ssize_t
 ftrace_event_write(struct file *file, const char __user *ubuf,
                   size_t cnt, loff_t *ppos)
 {
+       struct trace_parser parser;
        size_t read = 0;
-       int i, set = 1;
        ssize_t ret;
-       char *buf;
-       char ch;
 
        if (!cnt || cnt < 0)
                return 0;
@@ -211,60 +242,28 @@ ftrace_event_write(struct file *file, const char __user *ubuf,
        if (ret < 0)
                return ret;
 
-       ret = get_user(ch, ubuf++);
-       if (ret)
-               return ret;
-       read++;
-       cnt--;
-
-       /* skip white space */
-       while (cnt && isspace(ch)) {
-               ret = get_user(ch, ubuf++);
-               if (ret)
-                       return ret;
-               read++;
-               cnt--;
-       }
-
-       /* Only white space found? */
-       if (isspace(ch)) {
-               file->f_pos += read;
-               ret = read;
-               return ret;
-       }
-
-       buf = kmalloc(EVENT_BUF_SIZE+1, GFP_KERNEL);
-       if (!buf)
+       if (trace_parser_get_init(&parser, EVENT_BUF_SIZE + 1))
                return -ENOMEM;
 
-       if (cnt > EVENT_BUF_SIZE)
-               cnt = EVENT_BUF_SIZE;
+       read = trace_get_user(&parser, ubuf, cnt, ppos);
+
+       if (trace_parser_loaded((&parser))) {
+               int set = 1;
 
-       i = 0;
-       while (cnt && !isspace(ch)) {
-               if (!i && ch == '!')
+               if (*parser.buffer == '!')
                        set = 0;
-               else
-                       buf[i++] = ch;
 
-               ret = get_user(ch, ubuf++);
+               parser.buffer[parser.idx] = 0;
+
+               ret = ftrace_set_clr_event(parser.buffer + !set, set);
                if (ret)
-                       goto out_free;
-               read++;
-               cnt--;
+                       goto out_put;
        }
-       buf[i] = 0;
-
-       file->f_pos += read;
-
-       ret = ftrace_set_clr_event(buf, set);
-       if (ret)
-               goto out_free;
 
        ret = read;
 
- out_free:
-       kfree(buf);
+ out_put:
+       trace_parser_put(&parser);
 
        return ret;
 }
@@ -546,7 +545,7 @@ static int trace_write_header(struct trace_seq *s)
                                FIELD(unsigned char, flags),
                                FIELD(unsigned char, preempt_count),
                                FIELD(int, pid),
-                               FIELD(int, tgid));
+                               FIELD(int, lock_depth));
 }
 
 static ssize_t
@@ -574,7 +573,7 @@ event_format_read(struct file *filp, char __user *ubuf, size_t cnt,
        trace_seq_printf(s, "format:\n");
        trace_write_header(s);
 
-       r = call->show_format(s);
+       r = call->show_format(call, s);
        if (!r) {
                /*
                 * ug!  The format output is bigger than a PAGE!!
@@ -849,8 +848,10 @@ event_subsystem_dir(const char *name, struct dentry *d_events)
 
        /* First see if we did not already create this dir */
        list_for_each_entry(system, &event_subsystems, list) {
-               if (strcmp(system->name, name) == 0)
+               if (strcmp(system->name, name) == 0) {
+                       system->nr_events++;
                        return system->entry;
+               }
        }
 
        /* need to create new entry */
@@ -869,6 +870,7 @@ event_subsystem_dir(const char *name, struct dentry *d_events)
                return d_events;
        }
 
+       system->nr_events = 1;
        system->name = kstrdup(name, GFP_KERNEL);
        if (!system->name) {
                debugfs_remove(system->entry);
@@ -920,15 +922,6 @@ event_create_dir(struct ftrace_event_call *call, struct dentry *d_events,
        if (strcmp(call->system, TRACE_SYSTEM) != 0)
                d_events = event_subsystem_dir(call->system, d_events);
 
-       if (call->raw_init) {
-               ret = call->raw_init();
-               if (ret < 0) {
-                       pr_warning("Could not initialize trace point"
-                                  " events/%s\n", call->name);
-                       return ret;
-               }
-       }
-
        call->dir = debugfs_create_dir(call->name, d_events);
        if (!call->dir) {
                pr_warning("Could not create debugfs "
@@ -945,7 +938,7 @@ event_create_dir(struct ftrace_event_call *call, struct dentry *d_events,
                                          id);
 
        if (call->define_fields) {
-               ret = call->define_fields();
+               ret = call->define_fields(call);
                if (ret < 0) {
                        pr_warning("Could not initialize trace point"
                                   " events/%s\n", call->name);
@@ -987,6 +980,32 @@ struct ftrace_module_file_ops {
        struct file_operations          filter;
 };
 
+static void remove_subsystem_dir(const char *name)
+{
+       struct event_subsystem *system;
+
+       if (strcmp(name, TRACE_SYSTEM) == 0)
+               return;
+
+       list_for_each_entry(system, &event_subsystems, list) {
+               if (strcmp(system->name, name) == 0) {
+                       if (!--system->nr_events) {
+                               struct event_filter *filter = system->filter;
+
+                               debugfs_remove_recursive(system->entry);
+                               list_del(&system->list);
+                               if (filter) {
+                                       kfree(filter->filter_string);
+                                       kfree(filter);
+                               }
+                               kfree(system->name);
+                               kfree(system);
+                       }
+                       break;
+               }
+       }
+}
+
 static struct ftrace_module_file_ops *
 trace_create_file_ops(struct module *mod)
 {
@@ -1027,6 +1046,7 @@ static void trace_module_add_events(struct module *mod)
        struct ftrace_module_file_ops *file_ops = NULL;
        struct ftrace_event_call *call, *start, *end;
        struct dentry *d_events;
+       int ret;
 
        start = mod->trace_events;
        end = mod->trace_events + mod->num_trace_events;
@@ -1042,7 +1062,15 @@ static void trace_module_add_events(struct module *mod)
                /* The linker may leave blanks */
                if (!call->name)
                        continue;
-
+               if (call->raw_init) {
+                       ret = call->raw_init();
+                       if (ret < 0) {
+                               if (ret != -ENOSYS)
+                                       pr_warning("Could not initialize trace "
+                                       "point events/%s\n", call->name);
+                               continue;
+                       }
+               }
                /*
                 * This module has events, create file ops for this module
                 * if not already done.
@@ -1077,6 +1105,7 @@ static void trace_module_remove_events(struct module *mod)
                        list_del(&call->list);
                        trace_destroy_fields(call);
                        destroy_preds(call);
+                       remove_subsystem_dir(call->system);
                }
        }
 
@@ -1125,7 +1154,7 @@ static int trace_module_notify(struct notifier_block *self,
 }
 #endif /* CONFIG_MODULES */
 
-struct notifier_block trace_module_nb = {
+static struct notifier_block trace_module_nb = {
        .notifier_call = trace_module_notify,
        .priority = 0,
 };
@@ -1133,6 +1162,18 @@ struct notifier_block trace_module_nb = {
 extern struct ftrace_event_call __start_ftrace_events[];
 extern struct ftrace_event_call __stop_ftrace_events[];
 
+static char bootup_event_buf[COMMAND_LINE_SIZE] __initdata;
+
+static __init int setup_trace_event(char *str)
+{
+       strlcpy(bootup_event_buf, str, COMMAND_LINE_SIZE);
+       ring_buffer_expanded = 1;
+       tracing_selftest_disabled = 1;
+
+       return 1;
+}
+__setup("trace_event=", setup_trace_event);
+
 static __init int event_trace_init(void)
 {
        struct ftrace_event_call *call;
@@ -1140,6 +1181,8 @@ static __init int event_trace_init(void)
        struct dentry *entry;
        struct dentry *d_events;
        int ret;
+       char *buf = bootup_event_buf;
+       char *token;
 
        d_tracer = tracing_init_dentry();
        if (!d_tracer)
@@ -1179,12 +1222,34 @@ static __init int event_trace_init(void)
                /* The linker may leave blanks */
                if (!call->name)
                        continue;
+               if (call->raw_init) {
+                       ret = call->raw_init();
+                       if (ret < 0) {
+                               if (ret != -ENOSYS)
+                                       pr_warning("Could not initialize trace "
+                                       "point events/%s\n", call->name);
+                               continue;
+                       }
+               }
                list_add(&call->list, &ftrace_events);
                event_create_dir(call, d_events, &ftrace_event_id_fops,
                                 &ftrace_enable_fops, &ftrace_event_filter_fops,
                                 &ftrace_event_format_fops);
        }
 
+       while (true) {
+               token = strsep(&buf, ",");
+
+               if (!token)
+                       break;
+               if (!*token)
+                       continue;
+
+               ret = ftrace_set_clr_event(token, 1);
+               if (ret)
+                       pr_warning("Failed to enable trace event: %s\n", token);
+       }
+
        ret = register_module_notifier(&trace_module_nb);
        if (ret)
                pr_warning("Failed to register trace events module notifier\n");
@@ -1261,6 +1326,18 @@ static __init void event_trace_self_tests(void)
                if (!call->regfunc)
                        continue;
 
+/*
+ * Testing syscall events here is pretty useless, but
+ * we still do it if configured. But this is time consuming.
+ * What we really need is a user thread to perform the
+ * syscalls as we test.
+ */
+#ifndef CONFIG_EVENT_TRACE_TEST_SYSCALLS
+               if (call->system &&
+                   strcmp(call->system, "syscalls") == 0)
+                       continue;
+#endif
+
                pr_info("Testing event %s: ", call->name);
 
                /*
@@ -1334,12 +1411,13 @@ static __init void event_trace_self_tests(void)
 
 #ifdef CONFIG_FUNCTION_TRACER
 
-static DEFINE_PER_CPU(atomic_t, test_event_disable);
+static DEFINE_PER_CPU(atomic_t, ftrace_test_event_disable);
 
 static void
 function_test_events_call(unsigned long ip, unsigned long parent_ip)
 {
        struct ring_buffer_event *event;
+       struct ring_buffer *buffer;
        struct ftrace_entry *entry;
        unsigned long flags;
        long disabled;
@@ -1350,14 +1428,15 @@ function_test_events_call(unsigned long ip, unsigned long parent_ip)
        pc = preempt_count();
        resched = ftrace_preempt_disable();
        cpu = raw_smp_processor_id();
-       disabled = atomic_inc_return(&per_cpu(test_event_disable, cpu));
+       disabled = atomic_inc_return(&per_cpu(ftrace_test_event_disable, cpu));
 
        if (disabled != 1)
                goto out;
 
        local_save_flags(flags);
 
-       event = trace_current_buffer_lock_reserve(TRACE_FN, sizeof(*entry),
+       event = trace_current_buffer_lock_reserve(&buffer,
+                                                 TRACE_FN, sizeof(*entry),
                                                  flags, pc);
        if (!event)
                goto out;
@@ -1365,10 +1444,10 @@ function_test_events_call(unsigned long ip, unsigned long parent_ip)
        entry->ip                       = ip;
        entry->parent_ip                = parent_ip;
 
-       trace_nowake_buffer_unlock_commit(event, flags, pc);
+       trace_nowake_buffer_unlock_commit(buffer, event, flags, pc);
 
  out:
-       atomic_dec(&per_cpu(test_event_disable, cpu));
+       atomic_dec(&per_cpu(ftrace_test_event_disable, cpu));
        ftrace_preempt_enable(resched);
 }
 
@@ -1392,10 +1471,10 @@ static __init void event_trace_self_test_with_function(void)
 
 static __init int event_trace_self_tests_init(void)
 {
-
-       event_trace_self_tests();
-
-       event_trace_self_test_with_function();
+       if (!tracing_selftest_disabled) {
+               event_trace_self_tests();
+               event_trace_self_test_with_function();
+       }
 
        return 0;
 }