Re: [PATCH 04/13] tracing: Rename kvfree_rcu() to kvfree_rcu_mightsleep()

From: Steven Rostedt
Date: Wed Mar 15 2023 - 18:37:02 EST


On Thu, 9 Mar 2023 14:45:21 +0100
Uladzislau Rezki <urezki@xxxxxxxxx> wrote:

> > The kvfree_rcu()'s single argument name is deprecated therefore
> > rename it to kvfree_rcu_mightsleep() variant. The goal is explicitly
> > underline that it is for sleepable contexts.
> >
> > Cc: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
> > Signed-off-by: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx>
> >
> Could you please add you reviwed-by or Acked-by tags so we can bring
> our series with renaming for the next merge window?

I don't know. Perhaps we should just apply this patch and not worry about
sleeping and whatnot.

-- Steve

diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c
index 04f0fdae19a1..5de945a8f61d 100644
--- a/kernel/trace/trace_osnoise.c
+++ b/kernel/trace/trace_osnoise.c
@@ -76,6 +76,7 @@ static unsigned long osnoise_options = OSN_DEFAULT_OPTIONS;
struct osnoise_instance {
struct list_head list;
struct trace_array *tr;
+ struct rcu_head rcu;
};

static struct list_head osnoise_instances;
@@ -159,7 +160,7 @@ static void osnoise_unregister_instance(struct trace_array *tr)
if (!found)
return;

- kvfree_rcu(inst);
+ kvfree_rcu(inst, rcu);
}

/*
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 20d0c4a97633..ef5fafb40c76 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -1172,7 +1172,7 @@ int trace_probe_remove_file(struct trace_probe *tp,
return -ENOENT;

list_del_rcu(&link->list);
- kvfree_rcu(link);
+ kvfree_rcu(link, rcu);

if (list_empty(&tp->event->files))
trace_probe_clear_flag(tp, TP_FLAG_TRACE);
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index ef8ed3b65d05..e6037752dcf0 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -256,6 +256,7 @@ struct trace_probe {
struct event_file_link {
struct trace_event_file *file;
struct list_head list;
+ struct rcu_head rcu;
};

static inline bool trace_probe_test_flag(struct trace_probe *tp,