I know nothing about the issues behind this, but I'm forwarding it in case it's useful.
julia ---------- Forwarded message ---------- Date: Wed, 3 Aug 2016 13:26:56 +0800 From: kbuild test robot <[email protected]> To: [email protected] Cc: Julia Lawall <[email protected]> Subject: [PATCH] fix debugfs_simple_attr.cocci warnings CC: [email protected] In-Reply-To: <[email protected]> TO: Andi Kleen <[email protected]> CC: [email protected], [email protected], Andi Kleen <[email protected]> CC: [email protected], Andi Kleen <[email protected]> kernel/panic.c:561:0-23: WARNING: clear_warn_once_fops should be defined with DEFINE_DEBUGFS_ATTRIBUTE Use DEFINE_DEBUGFS_ATTRIBUTE rather than DEFINE_SIMPLE_ATTRIBUTE for debugfs files. Semantic patch information: Rationale: DEFINE_SIMPLE_ATTRIBUTE + debugfs_create_file() imposes some significant overhead as compared to DEFINE_DEBUGFS_ATTRIBUTE + debugfs_create_file_unsafe(). Generated by: scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci CC: Andi Kleen <[email protected]> Signed-off-by: Fengguang Wu <[email protected]> --- Please take the patch only if it's a positive warning. Thanks! panic.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) --- a/kernel/panic.c +++ b/kernel/panic.c @@ -558,16 +558,14 @@ static int clear_warn_once_set(void *dat return 0; } -DEFINE_SIMPLE_ATTRIBUTE(clear_warn_once_fops, - NULL, - clear_warn_once_set, - "%lld\n"); +DEFINE_DEBUGFS_ATTRIBUTE(clear_warn_once_fops, NULL, clear_warn_once_set, + "%lld\n"); static __init int register_warn_debugfs(void) { /* Don't care about failure */ - debugfs_create_file("clear_warn_once", 0644, NULL, - NULL, &clear_warn_once_fops); + debugfs_create_file_unsafe("clear_warn_once", 0644, NULL, NULL, + &clear_warn_once_fops); return 0; }
