Possible performance bug

[Chris Wright]

* Steve Grubb (sgrubb at redhat.com) wrote:
> On Friday 09 September 2005 17:10, Chris Wright wrote:
> > How's this one go?
> 
> I did the decision at the fork code to avoid pushing vars, doing call, doing 
> return, and popping the stack. I think we need to start doing that to avoid 
> overhead.

OK, just don't clutter core code with audit enabled tests.

thanks,
-chris
--

 include/linux/audit.h |   10 +++++++++-
 kernel/auditsc.c      |    8 +-------
 2 files changed, 10 insertions(+), 8 deletions(-)

Index: linus-2.6/kernel/auditsc.c
===================================================================
--- linus-2.6.orig/kernel/auditsc.c
+++ linus-2.6/kernel/auditsc.c
@@ -47,9 +47,6 @@
 */
 #define AUDIT_DEBUG 0
 
-/* No syscall auditing will take place unless audit_enabled != 0. */
-extern int audit_enabled;
-
 /* AUDIT_NAMES is the number of slots we reserve in the audit_context
  * for saving names from getname(). */
 #define AUDIT_NAMES    20
@@ -601,14 +598,11 @@ static inline struct audit_context *audi
  * if necessary.  Doing so turns on system call auditing for the
  * specified task.  This is called from copy_process, so no lock is
  * needed. */
-int audit_alloc(struct task_struct *tsk)
+int do_audit_alloc(struct task_struct *tsk)
 {
 	struct audit_context *context;
 	enum audit_state     state;
 
-	if (likely(!audit_enabled))
-		return 0; /* Return if not auditing. */
-
 	state = audit_filter_task(tsk);
 	if (likely(state == AUDIT_DISABLED))
 		return 0;
Index: linus-2.6/include/linux/audit.h
===================================================================
--- linus-2.6.orig/include/linux/audit.h
+++ linus-2.6/include/linux/audit.h
@@ -200,6 +200,8 @@ struct audit_buffer;
 struct audit_context;
 struct inode;
 
+extern int audit_enabled;
+
 #define AUDITSC_INVALID 0
 #define AUDITSC_SUCCESS 1
 #define AUDITSC_FAILURE 2
@@ -207,7 +209,13 @@ struct inode;
 #ifdef CONFIG_AUDITSYSCALL
 /* These are defined in auditsc.c */
 				/* Public API */
-extern int  audit_alloc(struct task_struct *task);
+extern int  do_audit_alloc(struct task_struct *task);
+static inline int  audit_alloc(struct task_struct *task) {
+	if (likely(!audit_enabled))
+		clear_tsk_thread_flag(task, TIF_SYSCALL_AUDIT);
+		return 0;
+	return do_audit_alloc(task);	
+}
 extern void audit_free(struct task_struct *task);
 extern void audit_syscall_entry(struct task_struct *task, int arch,
 				int major, unsigned long a0, unsigned long a1,