From fb5a613b4f310d6d520daf295547ab35b0ac58a3 Mon Sep 17 00:00:00 2001 From: Andreea-Cristina Bernat Date: Fri, 22 Aug 2014 17:28:22 +0300 Subject: [PATCH] kernel: trace_syscalls: Replace rcu_assign_pointer() with RCU_INIT_POINTER() The uses of "rcu_assign_pointer()" are NULLing out the pointers. According to RCU_INIT_POINTER()'s block comment: "1. This use of RCU_INIT_POINTER() is NULLing out the pointer" it is better to use it instead of rcu_assign_pointer() because it has a smaller overhead. The following Coccinelle semantic patch was used: @@ @@ - rcu_assign_pointer + RCU_INIT_POINTER (..., NULL) Link: http://lkml.kernel.org/p/20140822142822.GA32391@ada Signed-off-by: Andreea-Cristina Bernat Signed-off-by: Steven Rostedt --- kernel/trace/trace_syscalls.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index 759d5e004517..4dc8b79c5f75 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -425,7 +425,7 @@ static void unreg_event_syscall_enter(struct ftrace_event_file *file, return; mutex_lock(&syscall_trace_lock); tr->sys_refcount_enter--; - rcu_assign_pointer(tr->enter_syscall_files[num], NULL); + RCU_INIT_POINTER(tr->enter_syscall_files[num], NULL); if (!tr->sys_refcount_enter) unregister_trace_sys_enter(ftrace_syscall_enter, tr); mutex_unlock(&syscall_trace_lock); @@ -463,7 +463,7 @@ static void unreg_event_syscall_exit(struct ftrace_event_file *file, return; mutex_lock(&syscall_trace_lock); tr->sys_refcount_exit--; - rcu_assign_pointer(tr->exit_syscall_files[num], NULL); + RCU_INIT_POINTER(tr->exit_syscall_files[num], NULL); if (!tr->sys_refcount_exit) unregister_trace_sys_exit(ftrace_syscall_exit, tr); mutex_unlock(&syscall_trace_lock); -- 2.39.5