diff options
Diffstat (limited to 'kernel/trace/trace_fprobe.c')
| -rw-r--r-- | kernel/trace/trace_fprobe.c | 30 |
1 files changed, 14 insertions, 16 deletions
diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c index e27305d31fc5..985ff98272da 100644 --- a/kernel/trace/trace_fprobe.c +++ b/kernel/trace/trace_fprobe.c @@ -920,13 +920,8 @@ static void __find_tracepoint_module_cb(struct tracepoint *tp, struct module *mo if (!data->tpoint && !strcmp(data->tp_name, tp->name)) { data->tpoint = tp; - if (!data->mod) { + if (!data->mod) data->mod = mod; - if (!try_module_get(data->mod)) { - data->tpoint = NULL; - data->mod = NULL; - } - } } } @@ -938,13 +933,7 @@ static void __find_tracepoint_cb(struct tracepoint *tp, void *priv) data->tpoint = tp; } -/* - * Find a tracepoint from kernel and module. If the tracepoint is in a module, - * this increments the module refcount to prevent unloading until the - * trace_fprobe is registered to the list. After registering the trace_fprobe - * on the trace_fprobe list, the module refcount is decremented because - * tracepoint_probe_module_cb will handle it. - */ +/* Find a tracepoint from kernel and module. */ static struct tracepoint *find_tracepoint(const char *tp_name, struct module **tp_mod) { @@ -973,6 +962,7 @@ static void reenable_trace_fprobe(struct trace_fprobe *tf) } } +/* Find a tracepoint from specified module. */ static struct tracepoint *find_tracepoint_in_module(struct module *mod, const char *tp_name) { @@ -1008,10 +998,13 @@ static int __tracepoint_probe_module_cb(struct notifier_block *self, reenable_trace_fprobe(tf); } } else if (val == MODULE_STATE_GOING && tp_mod->mod == tf->mod) { - tracepoint_probe_unregister(tf->tpoint, + unregister_fprobe(&tf->fp); + if (trace_fprobe_is_tracepoint(tf)) { + tracepoint_probe_unregister(tf->tpoint, tf->tpoint->probestub, NULL); - tf->tpoint = NULL; - tf->mod = NULL; + tf->tpoint = TRACEPOINT_STUB; + tf->mod = NULL; + } } } mutex_unlock(&event_mutex); @@ -1176,6 +1169,11 @@ static int trace_fprobe_create_internal(int argc, const char *argv[], if (is_tracepoint) { ctx->flags |= TPARG_FL_TPOINT; tpoint = find_tracepoint(symbol, &tp_mod); + /* lock module until register this tprobe. */ + if (tp_mod && !try_module_get(tp_mod)) { + tpoint = NULL; + tp_mod = NULL; + } if (tpoint) { ctx->funcname = kallsyms_lookup( (unsigned long)tpoint->probestub, |