uprobes/tracing: Kill uprobe_trace_consumer, embed uprobe_consumer into trace_uprobe

trace_uprobe->consumer and "struct uprobe_trace_consumer" add the
unnecessary indirection and complicate the code for no reason.

This patch simply embeds uprobe_consumer into "struct trace_uprobe",
all other changes only fix the compilation errors.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>

1 files changed, 6 insertions, 29 deletions

diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index d6c6e2a345a7..9c8babbfd11b 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -31,17 +31,11 @@
 /*
  * uprobe event core functions
  */
-struct trace_uprobe;
-struct uprobe_trace_consumer {
-        struct uprobe_consumer          cons;
-        struct trace_uprobe             *tu;
-};
-
 struct trace_uprobe {
         struct list_head                list;
         struct ftrace_event_class       class;
         struct ftrace_event_call        call;
-        struct uprobe_trace_consumer    *consumer;
+        struct uprobe_consumer          consumer;
         struct inode                    *inode;
         char                            *filename;
         unsigned long                   offset;
@@ -92,6 +86,7 @@ alloc_trace_uprobe(const char *group, const char *event, int nargs)
                 goto error;
 
         INIT_LIST_HEAD(&tu->list);
+        tu->consumer.handler = uprobe_dispatcher;
         return tu;
 
 error:
@@ -546,27 +541,15 @@ static inline bool is_trace_uprobe_enabled(struct trace_uprobe *tu)
 
 static int probe_event_enable(struct trace_uprobe *tu, int flag)
 {
-        struct uprobe_trace_consumer *utc;
         int ret = 0;
 
         if (is_trace_uprobe_enabled(tu))
                 return -EINTR;
 
-        utc = kzalloc(sizeof(struct uprobe_trace_consumer), GFP_KERNEL);
-        if (!utc)
-                return -EINTR;
-
-        utc->cons.handler = uprobe_dispatcher;
-        utc->tu = tu;
-        tu->consumer = utc;
         tu->flags |= flag;
-
-        ret = uprobe_register(tu->inode, tu->offset, &utc->cons);
-        if (ret) {
-                tu->consumer = NULL;
+        ret = uprobe_register(tu->inode, tu->offset, &tu->consumer);
+        if (ret)
                 tu->flags &= ~flag;
-                kfree(utc);
-        }
 
         return ret;
 }
@@ -576,10 +559,8 @@ static void probe_event_disable(struct trace_uprobe *tu, int flag)
         if (!is_trace_uprobe_enabled(tu))
                 return;
 
-        uprobe_unregister(tu->inode, tu->offset, &tu->consumer->cons);
+        uprobe_unregister(tu->inode, tu->offset, &tu->consumer);
         tu->flags &= ~flag;
-        kfree(tu->consumer);
-        tu->consumer = NULL;
 }
 
 static int uprobe_event_define_fields(struct ftrace_event_call *event_call)
@@ -717,13 +698,9 @@ int trace_uprobe_register(struct ftrace_event_call *event, enum trace_reg type,
 
 static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs)
 {
-        struct uprobe_trace_consumer *utc;
         struct trace_uprobe *tu;
 
-        utc = container_of(con, struct uprobe_trace_consumer, cons);
-        tu = utc->tu;
-        if (!tu || tu->consumer != utc)
-                return 0;
+        tu = container_of(con, struct trace_uprobe, consumer);
 
         if (tu->flags & TP_FLAG_TRACE)
                 uprobe_trace_func(tu, regs);