Merge tag 'trace-3.15-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull more tracing updates from Steven Rostedt:
 "This includes the final patch to clean up and fix the issue with the
  design of tracepoints and how a user could register a tracepoint and
  have that tracepoint not be activated but no error was shown.

  The design was for an out of tree module but broke in tree users.  The
  clean up was to remove the saving of the hash table of tracepoint
  names such that they can be enabled before they exist (enabling a
  module tracepoint before that module is loaded).  This added more
  complexity than needed.  The clean up was to remove that code and just
  enable tracepoints that exist or fail if they do not.

  This removed a lot of code as well as the complexity that it brought.
  As a side effect, instead of registering a tracepoint by its name, the
  tracepoint needs to be registered with the tracepoint descriptor.
  This removes having to duplicate the tracepoint names that are
  enabled.

  The second patch was added that simplified the way modules were
  searched for.

  This cleanup required changes that were in the 3.15 queue as well as
  some changes that were added late in the 3.14-rc cycle.  This final
  change waited till the two were merged in upstream and then the change
  was added and full tests were run.  Unfortunately, the test found some
  errors, but after it was already submitted to the for-next branch and
  not to be rebased.  Sparse errors were detected by Fengguang Wu's bot
  tests, and my internal tests discovered that the anonymous union
  initialization triggered a bug in older gcc compilers.  Luckily, there
  was a bugzilla for the gcc bug which gave a work around to the
  problem.  The third and fourth patch handled the sparse error and the
  gcc bug respectively.

  A final patch was tagged along to fix a missing documentation for the
  README file"

* tag 'trace-3.15-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Add missing function triggers dump and cpudump to README
  tracing: Fix anonymous unions in struct ftrace_event_call
  tracepoint: Fix sparse warnings in tracepoint.c
  tracepoint: Simplify tracepoint module search
  tracepoint: Use struct pointer instead of name hash for reg/unreg tracepoints

7 files changed, 66 insertions, 42 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 9be67c5e5b0f..e3e665685ee5 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3611,6 +3611,8 @@ static const char readme_msg[] =
 #ifdef CONFIG_TRACER_SNAPSHOT
         "\t\t      snapshot\n"
 #endif
+        "\t\t      dump\n"
+        "\t\t      cpudump\n"
         "\t     example: echo do_fault:traceoff > set_ftrace_filter\n"
         "\t              echo do_trap:traceoff:3 > set_ftrace_filter\n"
         "\t     The first one will disable tracing every time do_fault is hit\n"
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 83a4378dc5e0..3ddfd8f62c05 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -223,24 +223,25 @@ int ftrace_event_reg(struct ftrace_event_call *call,
 {
         struct ftrace_event_file *file = data;
 
+        WARN_ON(!(call->flags & TRACE_EVENT_FL_TRACEPOINT));
         switch (type) {
         case TRACE_REG_REGISTER:
-                return tracepoint_probe_register(call->name,
+                return tracepoint_probe_register(call->tp,
                                                  call->class->probe,
                                                  file);
         case TRACE_REG_UNREGISTER:
-                tracepoint_probe_unregister(call->name,
+                tracepoint_probe_unregister(call->tp,
                                             call->class->probe,
                                             file);
                 return 0;
 
 #ifdef CONFIG_PERF_EVENTS
         case TRACE_REG_PERF_REGISTER:
-                return tracepoint_probe_register(call->name,
+                return tracepoint_probe_register(call->tp,
                                                  call->class->perf_probe,
                                                  call);
         case TRACE_REG_PERF_UNREGISTER:
-                tracepoint_probe_unregister(call->name,
+                tracepoint_probe_unregister(call->tp,
                                             call->class->perf_probe,
                                             call);
                 return 0;
@@ -352,7 +353,7 @@ static int __ftrace_event_enable_disable(struct ftrace_event_file *file,
                         if (ret) {
                                 tracing_stop_cmdline_record();
                                 pr_info("event trace: Could not enable event "
-                                        "%s\n", call->name);
+                                        "%s\n", ftrace_event_name(call));
                                 break;
                         }
                         set_bit(FTRACE_EVENT_FL_ENABLED_BIT, &file->flags);
@@ -481,27 +482,29 @@ __ftrace_set_clr_event_nolock(struct trace_array *tr, const char *match,
 {
         struct ftrace_event_file *file;
         struct ftrace_event_call *call;
+        const char *name;
         int ret = -EINVAL;
 
         list_for_each_entry(file, &tr->events, list) {
 
                 call = file->event_call;
+                name = ftrace_event_name(call);
 
-                if (!call->name || !call->class || !call->class->reg)
+                if (!name || !call->class || !call->class->reg)
                         continue;
 
                 if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)
                         continue;
 
                 if (match &&
-                    strcmp(match, call->name) != 0 &&
+                    strcmp(match, name) != 0 &&
                     strcmp(match, call->class->system) != 0)
                         continue;
 
                 if (sub && strcmp(sub, call->class->system) != 0)
                         continue;
 
-                if (event && strcmp(event, call->name) != 0)
+                if (event && strcmp(event, name) != 0)
                         continue;
 
                 ftrace_event_enable_disable(file, set);
@@ -699,7 +702,7 @@ static int t_show(struct seq_file *m, void *v)
 
         if (strcmp(call->class->system, TRACE_SYSTEM) != 0)
                 seq_printf(m, "%s:", call->class->system);
-        seq_printf(m, "%s\n", call->name);
+        seq_printf(m, "%s\n", ftrace_event_name(call));
 
         return 0;
 }
@@ -792,7 +795,7 @@ system_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
         mutex_lock(&event_mutex);
         list_for_each_entry(file, &tr->events, list) {
                 call = file->event_call;
-                if (!call->name || !call->class || !call->class->reg)
+                if (!ftrace_event_name(call) || !call->class || !call->class->reg)
                         continue;
 
                 if (system && strcmp(call->class->system, system->name) != 0)
@@ -907,7 +910,7 @@ static int f_show(struct seq_file *m, void *v)
 
         switch ((unsigned long)v) {
         case FORMAT_HEADER:
-                seq_printf(m, "name: %s\n", call->name);
+                seq_printf(m, "name: %s\n", ftrace_event_name(call));
                 seq_printf(m, "ID: %d\n", call->event.type);
                 seq_printf(m, "format:\n");
                 return 0;
@@ -1527,6 +1530,7 @@ event_create_dir(struct dentry *parent, struct ftrace_event_file *file)
         struct trace_array *tr = file->tr;
         struct list_head *head;
         struct dentry *d_events;
+        const char *name;
         int ret;
 
         /*
@@ -1540,10 +1544,11 @@ event_create_dir(struct dentry *parent, struct ftrace_event_file *file)
         } else
                 d_events = parent;
 
-        file->dir = debugfs_create_dir(call->name, d_events);
+        name = ftrace_event_name(call);
+        file->dir = debugfs_create_dir(name, d_events);
         if (!file->dir) {
                 pr_warning("Could not create debugfs '%s' directory\n",
-                           call->name);
+                           name);
                 return -1;
         }
 
@@ -1567,7 +1572,7 @@ event_create_dir(struct dentry *parent, struct ftrace_event_file *file)
                 ret = call->class->define_fields(call);
                 if (ret < 0) {
                         pr_warning("Could not initialize trace point"
-                                   " events/%s\n", call->name);
+                                   " events/%s\n", name);
                         return -1;
                 }
         }
@@ -1631,15 +1636,17 @@ static void event_remove(struct ftrace_event_call *call)
 static int event_init(struct ftrace_event_call *call)
 {
         int ret = 0;
+        const char *name;
 
-        if (WARN_ON(!call->name))
+        name = ftrace_event_name(call);
+        if (WARN_ON(!name))
                 return -EINVAL;
 
         if (call->class->raw_init) {
                 ret = call->class->raw_init(call);
                 if (ret < 0 && ret != -ENOSYS)
                         pr_warn("Could not initialize trace events/%s\n",
-                                call->name);
+                                name);
         }
 
         return ret;
@@ -1885,7 +1892,7 @@ __trace_add_event_dirs(struct trace_array *tr)
                 ret = __trace_add_new_event(call, tr);
                 if (ret < 0)
                         pr_warning("Could not create directory for event %s\n",
-                                   call->name);
+                                   ftrace_event_name(call));
         }
 }
 
@@ -1894,18 +1901,20 @@ find_event_file(struct trace_array *tr, const char *system,  const char *event)
 {
         struct ftrace_event_file *file;
         struct ftrace_event_call *call;
+        const char *name;
 
         list_for_each_entry(file, &tr->events, list) {
 
                 call = file->event_call;
+                name = ftrace_event_name(call);
 
-                if (!call->name || !call->class || !call->class->reg)
+                if (!name || !call->class || !call->class->reg)
                         continue;
 
                 if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)
                         continue;
 
-                if (strcmp(event, call->name) == 0 &&
+                if (strcmp(event, name) == 0 &&
                     strcmp(system, call->class->system) == 0)
                         return file;
         }
@@ -1973,7 +1982,7 @@ event_enable_print(struct seq_file *m, unsigned long ip,
         seq_printf(m, "%s:%s:%s",
                    data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR,
                    data->file->event_call->class->system,
-                   data->file->event_call->name);
+                   ftrace_event_name(data->file->event_call));
 
         if (data->count == -1)
                 seq_printf(m, ":unlimited\n");
@@ -2193,7 +2202,7 @@ __trace_early_add_event_dirs(struct trace_array *tr)
                 ret = event_create_dir(tr->event_dir, file);
                 if (ret < 0)
                         pr_warning("Could not create directory for event %s\n",
-                                   file->event_call->name);
+                                   ftrace_event_name(file->event_call));
         }
 }
 
@@ -2217,7 +2226,7 @@ __trace_early_add_events(struct trace_array *tr)
                 ret = __trace_early_add_new_event(call, tr);
                 if (ret < 0)
                         pr_warning("Could not create early event %s\n",
-                                   call->name);
+                                   ftrace_event_name(call));
         }
 }
 
@@ -2549,7 +2558,7 @@ static __init void event_trace_self_tests(void)
                         continue;
 #endif
 
-                pr_info("Testing event %s: ", call->name);
+                pr_info("Testing event %s: ", ftrace_event_name(call));
 
                 /*
                  * If an event is already enabled, someone is using
diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
index 8efbb69b04f0..925f537f07d1 100644
--- a/kernel/trace/trace_events_trigger.c
+++ b/kernel/trace/trace_events_trigger.c
@@ -1095,7 +1095,7 @@ event_enable_trigger_print(struct seq_file *m, struct event_trigger_ops *ops,
         seq_printf(m, "%s:%s:%s",
                    enable_data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR,
                    enable_data->file->event_call->class->system,
-                   enable_data->file->event_call->name);
+                   ftrace_event_name(enable_data->file->event_call));
 
         if (data->count == -1)
                 seq_puts(m, ":unlimited");
diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c
index ee0a5098ac43..d4ddde28a81a 100644
--- a/kernel/trace/trace_export.c
+++ b/kernel/trace/trace_export.c
@@ -173,9 +173,11 @@ struct ftrace_event_class __refdata event_class_ftrace_##call = {	\
 };                                                                      \
                                                                         \
 struct ftrace_event_call __used event_##call = {                        \
-        .name                   = #call,                                \
-        .event.type             = etype,                                \
         .class                  = &event_class_ftrace_##call,           \
+        {                                                               \
+                .name                   = #call,                        \
+        },                                                              \
+        .event.type             = etype,                                \
         .print_fmt              = print,                                \
         .flags                  = TRACE_EVENT_FL_IGNORE_ENABLE | TRACE_EVENT_FL_USE_CALL_FILTER, \
 };                                                                      \
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index d021d21dd150..903ae28962be 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -341,7 +341,7 @@ static struct trace_kprobe *find_trace_kprobe(const char *event,
         struct trace_kprobe *tk;
 
         list_for_each_entry(tk, &probe_list, list)
-                if (strcmp(tk->tp.call.name, event) == 0 &&
+                if (strcmp(ftrace_event_name(&tk->tp.call), event) == 0 &&
                     strcmp(tk->tp.call.class->system, group) == 0)
                         return tk;
         return NULL;
@@ -516,7 +516,8 @@ static int register_trace_kprobe(struct trace_kprobe *tk)
         mutex_lock(&probe_lock);
 
         /* Delete old (same name) event if exist */
-        old_tk = find_trace_kprobe(tk->tp.call.name, tk->tp.call.class->system);
+        old_tk = find_trace_kprobe(ftrace_event_name(&tk->tp.call),
+                        tk->tp.call.class->system);
         if (old_tk) {
                 ret = unregister_trace_kprobe(old_tk);
                 if (ret < 0)
@@ -564,7 +565,8 @@ static int trace_kprobe_module_callback(struct notifier_block *nb,
                         if (ret)
                                 pr_warning("Failed to re-register probe %s on"
                                            "%s: %d\n",
-                                           tk->tp.call.name, mod->name, ret);
+                                           ftrace_event_name(&tk->tp.call),
+                                           mod->name, ret);
                 }
         }
         mutex_unlock(&probe_lock);
@@ -818,7 +820,8 @@ static int probes_seq_show(struct seq_file *m, void *v)
         int i;
 
         seq_printf(m, "%c", trace_kprobe_is_return(tk) ? 'r' : 'p');
-        seq_printf(m, ":%s/%s", tk->tp.call.class->system, tk->tp.call.name);
+        seq_printf(m, ":%s/%s", tk->tp.call.class->system,
+                        ftrace_event_name(&tk->tp.call));
 
         if (!tk->symbol)
                 seq_printf(m, " 0x%p", tk->rp.kp.addr);
@@ -876,7 +879,8 @@ static int probes_profile_seq_show(struct seq_file *m, void *v)
 {
         struct trace_kprobe *tk = v;
 
-        seq_printf(m, "  %-44s %15lu %15lu\n", tk->tp.call.name, tk->nhit,
+        seq_printf(m, "  %-44s %15lu %15lu\n",
+                   ftrace_event_name(&tk->tp.call), tk->nhit,
                    tk->rp.kp.nmissed);
 
         return 0;
@@ -1011,7 +1015,7 @@ print_kprobe_event(struct trace_iterator *iter, int flags,
         field = (struct kprobe_trace_entry_head *)iter->ent;
         tp = container_of(event, struct trace_probe, call.event);
 
-        if (!trace_seq_printf(s, "%s: (", tp->call.name))
+        if (!trace_seq_printf(s, "%s: (", ftrace_event_name(&tp->call)))
                 goto partial;
 
         if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET))
@@ -1047,7 +1051,7 @@ print_kretprobe_event(struct trace_iterator *iter, int flags,
         field = (struct kretprobe_trace_entry_head *)iter->ent;
         tp = container_of(event, struct trace_probe, call.event);
 
-        if (!trace_seq_printf(s, "%s: (", tp->call.name))
+        if (!trace_seq_printf(s, "%s: (", ftrace_event_name(&tp->call)))
                 goto partial;
 
         if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET))
@@ -1286,7 +1290,8 @@ static int register_kprobe_event(struct trace_kprobe *tk)
         call->data = tk;
         ret = trace_add_event_call(call);
         if (ret) {
-                pr_info("Failed to register kprobe event: %s\n", call->name);
+                pr_info("Failed to register kprobe event: %s\n",
+                        ftrace_event_name(call));
                 kfree(call->print_fmt);
                 unregister_ftrace_event(&call->event);
         }
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index ca0e79e2abaa..a436de18aa99 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -431,7 +431,7 @@ int ftrace_raw_output_prep(struct trace_iterator *iter,
         }
 
         trace_seq_init(p);
-        ret = trace_seq_printf(s, "%s: ", event->name);
+        ret = trace_seq_printf(s, "%s: ", ftrace_event_name(event));
         if (!ret)
                 return TRACE_TYPE_PARTIAL_LINE;
 
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index e4473367e7a4..930e51462dc8 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -294,7 +294,7 @@ static struct trace_uprobe *find_probe_event(const char *event, const char *grou
         struct trace_uprobe *tu;
 
         list_for_each_entry(tu, &uprobe_list, list)
-                if (strcmp(tu->tp.call.name, event) == 0 &&
+                if (strcmp(ftrace_event_name(&tu->tp.call), event) == 0 &&
                     strcmp(tu->tp.call.class->system, group) == 0)
                         return tu;
 
@@ -324,7 +324,8 @@ static int register_trace_uprobe(struct trace_uprobe *tu)
         mutex_lock(&uprobe_lock);
 
         /* register as an event */
-        old_tu = find_probe_event(tu->tp.call.name, tu->tp.call.class->system);
+        old_tu = find_probe_event(ftrace_event_name(&tu->tp.call),
+                        tu->tp.call.class->system);
         if (old_tu) {
                 /* delete old event */
                 ret = unregister_trace_uprobe(old_tu);
@@ -599,7 +600,8 @@ static int probes_seq_show(struct seq_file *m, void *v)
         char c = is_ret_probe(tu) ? 'r' : 'p';
         int i;
 
-        seq_printf(m, "%c:%s/%s", c, tu->tp.call.class->system, tu->tp.call.name);
+        seq_printf(m, "%c:%s/%s", c, tu->tp.call.class->system,
+                        ftrace_event_name(&tu->tp.call));
         seq_printf(m, " %s:0x%p", tu->filename, (void *)tu->offset);
 
         for (i = 0; i < tu->tp.nr_args; i++)
@@ -649,7 +651,8 @@ static int probes_profile_seq_show(struct seq_file *m, void *v)
 {
         struct trace_uprobe *tu = v;
 
-        seq_printf(m, "  %s %-44s %15lu\n", tu->filename, tu->tp.call.name, tu->nhit);
+        seq_printf(m, "  %s %-44s %15lu\n", tu->filename,
+                        ftrace_event_name(&tu->tp.call), tu->nhit);
         return 0;
 }
 
@@ -844,12 +847,14 @@ print_uprobe_event(struct trace_iterator *iter, int flags, struct trace_event *e
         tu = container_of(event, struct trace_uprobe, tp.call.event);
 
         if (is_ret_probe(tu)) {
-                if (!trace_seq_printf(s, "%s: (0x%lx <- 0x%lx)", tu->tp.call.name,
+                if (!trace_seq_printf(s, "%s: (0x%lx <- 0x%lx)",
+                                        ftrace_event_name(&tu->tp.call),
                                         entry->vaddr[1], entry->vaddr[0]))
                         goto partial;
                 data = DATAOF_TRACE_ENTRY(entry, true);
         } else {
-                if (!trace_seq_printf(s, "%s: (0x%lx)", tu->tp.call.name,
+                if (!trace_seq_printf(s, "%s: (0x%lx)",
+                                        ftrace_event_name(&tu->tp.call),
                                         entry->vaddr[0]))
                         goto partial;
                 data = DATAOF_TRACE_ENTRY(entry, false);
@@ -1275,7 +1280,8 @@ static int register_uprobe_event(struct trace_uprobe *tu)
         ret = trace_add_event_call(call);
 
         if (ret) {
-                pr_info("Failed to register uprobe event: %s\n", call->name);
+                pr_info("Failed to register uprobe event: %s\n",
+                        ftrace_event_name(call));
                 kfree(call->print_fmt);
                 unregister_ftrace_event(&call->event);
         }