tracing: tprobe-events: Remove mod field from tprobe-event

Remove unneeded 'mod' struct module pointer field from trace_fprobe
because we don't need to save this info.

Link: https://lore.kernel.org/all/174343535351.843280.5868426549023332120.stgit@devnote2/
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c
index b40fa59159ac521ef17aa3318db35de5ef491576..017d6ebfdf8b63b35a770be6d5c5a334be867b19 100644 (file)
--- a/kernel/trace/trace_fprobe.c
+++ b/kernel/trace/trace_fprobe.c
@@ -46,7 +46,6 @@ struct trace_fprobe {
        struct fprobe           fp;
        const char              *symbol;
        struct tracepoint       *tpoint;
-       struct module           *mod;
        struct trace_probe      tp;
 };
 
@@ -426,7 +425,6 @@ static struct trace_fprobe *alloc_trace_fprobe(const char *group,
                                               const char *event,
                                               const char *symbol,
                                               struct tracepoint *tpoint,
-                                              struct module *mod,
                                               int nargs, bool is_return)
 {
        struct trace_fprobe *tf __free(free_trace_fprobe) = NULL;
@@ -446,7 +444,6 @@ static struct trace_fprobe *alloc_trace_fprobe(const char *group,
                tf->fp.entry_handler = fentry_dispatcher;
 
        tf->tpoint = tpoint;
-       tf->mod = mod;
 
        ret = trace_probe_init(&tf->tp, event, group, false, nargs);
        if (ret < 0)
@@ -776,7 +773,6 @@ static void __unregister_trace_fprobe(struct trace_fprobe *tf)
                        tracepoint_probe_unregister(tf->tpoint,
                                        tf->tpoint->probestub, NULL);
                        tf->tpoint = NULL;
-                       tf->mod = NULL;
                }
        }
 }
@@ -1001,23 +997,23 @@ static int __tracepoint_probe_module_cb(struct notifier_block *self,
 
        mutex_lock(&event_mutex);
        for_each_trace_fprobe(tf, pos) {
+               if (!trace_fprobe_is_tracepoint(tf))
+                       continue;
                if (val == MODULE_STATE_COMING && tf->tpoint == TRACEPOINT_STUB) {
                        tpoint = find_tracepoint_in_module(tp_mod->mod, tf->symbol);
                        if (tpoint) {
                                tf->tpoint = tpoint;
-                               tf->mod = tp_mod->mod;
                                if (!WARN_ON_ONCE(__regsiter_tracepoint_fprobe(tf)) &&
                                    trace_probe_is_enabled(&tf->tp))
                                        reenable_trace_fprobe(tf);
                        }
-               } else if (val == MODULE_STATE_GOING && tp_mod->mod == tf->mod) {
+               } else if (val == MODULE_STATE_GOING &&
+                          tf->tpoint != TRACEPOINT_STUB &&
+                          within_module((unsigned long)tf->tpoint->probestub, tp_mod->mod)) {
                        unregister_fprobe(&tf->fp);
-                       if (trace_fprobe_is_tracepoint(tf)) {
-                               tracepoint_probe_unregister(tf->tpoint,
-                                       tf->tpoint->probestub, NULL);
-                               tf->tpoint = TRACEPOINT_STUB;
-                               tf->mod = NULL;
-                       }
+                       tracepoint_probe_unregister(tf->tpoint,
+                               tf->tpoint->probestub, NULL);
+                       tf->tpoint = TRACEPOINT_STUB;
                }
        }
        mutex_unlock(&event_mutex);
@@ -1218,8 +1214,7 @@ static int trace_fprobe_create_internal(int argc, const char *argv[],
                return ret;
 
        /* setup a probe */
-       tf = alloc_trace_fprobe(group, event, symbol, tpoint, tp_mod,
-                               argc, is_return);
+       tf = alloc_trace_fprobe(group, event, symbol, tpoint, argc, is_return);
        if (IS_ERR(tf)) {
                ret = PTR_ERR(tf);
                /* This must return -ENOMEM, else there is a bug */