Re: [PATCH net-next v4] net: psample: Introduce stubs to remove NIC driver dependency
From: Jakub Kicinski <kuba@kernel.org>
Date: 2021-01-29 21:51:49
On Thu, 28 Jan 2021 09:45:43 +0800 Chris Mi wrote:
In order to send sampled packets to userspace, NIC driver calls psample api directly. But it creates a hard dependency on module psample. Introduce psample_ops to remove the hard dependency. It is initialized when psample module is loaded and set to NULL when the module is unloaded. Reported-by: kernel test robot <redacted> Signed-off-by: Chris Mi <redacted> Reviewed-by: Jiri Pirko <redacted>
quoted hunk ↗ jump to hunk
diff --git a/include/net/psample.h b/include/net/psample.h index 68ae16bb0a4a..e6a73128de59 100644 --- a/include/net/psample.h +++ b/include/net/psample.h@@ -4,6 +4,7 @@ #include <uapi/linux/psample.h> #include <linux/list.h> +#include <linux/skbuff.h>
Forward declaration should be enough.
struct psample_group {
struct list_head list; static void __exit psample_module_exit(void)
{
+ RCU_INIT_POINTER(psample_ops, NULL);I think you can use rcu_assign_pointer(), it handles constants right these days. Please add a comment here saying that you depend on genl_unregister_family() executing synchronize_rcu() and name the function where it does so.
genl_unregister_family(&psample_nl_family); }
quoted hunk ↗ jump to hunk
diff --git a/net/sched/psample_stub.c b/net/sched/psample_stub.c new file mode 100644 index 000000000000..0615a7b64000 --- /dev/null +++ b/net/sched/psample_stub.c@@ -0,0 +1,7 @@ +// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB +/* Copyright (c) 2021 Mellanox Technologies. */ + +#include <net/psample.h>
Forward declaration is sufficient.
+const struct psample_ops __rcu *psample_ops __read_mostly; +EXPORT_SYMBOL_GPL(psample_ops);