[PATCH] Reduce bkl usage in do_coredump

A patch that reduces bkl usage in do_coredump.  I don't see anywhere that
it is necessary except for the call to format_corename, which is controlled
via sysctl (sys_sysctl holds the bkl).

Also make format_corename() static.
Signed-off-by: Josh Aas <josha@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

fs/exec.c

@@ -1211,7 +1211,7 @@ EXPORT_SYMBOL(set_binfmt);
  * name into corename, which must have space for at least
  * CORENAME_MAX_SIZE bytes plus one byte for the zero terminator.
  */
-void format_corename(char *corename, const char *pattern, long signr)
+static void format_corename(char *corename, const char *pattern, long signr)
 {
 	const char *pat_ptr = pattern;
 	char *out_ptr = corename;
@@ -1375,7 +1375,6 @@ int do_coredump(long signr, int exit_code, struct pt_regs * regs)
 	struct file * file;
 	int retval = 0;
 
-	lock_kernel();
 	binfmt = current->binfmt;
 	if (!binfmt || !binfmt->core_dump)
 		goto fail;
@@ -1393,7 +1392,13 @@ int do_coredump(long signr, int exit_code, struct pt_regs * regs)
 	if (current->rlim[RLIMIT_CORE].rlim_cur < binfmt->min_coredump)
 		goto fail_unlock;
 
- 	format_corename(corename, core_pattern, signr);
+	/*
+	 * lock_kernel() because format_corename() is controlled by sysctl, which
+	 * uses lock_kernel()
+	 */
+ 	lock_kernel();
+	format_corename(corename, core_pattern, signr);
+	unlock_kernel();
 	file = filp_open(corename, O_CREAT | 2 | O_NOFOLLOW | O_LARGEFILE, 0600);
 	if (IS_ERR(file))
 		goto fail_unlock;
@@ -1420,6 +1425,5 @@ int do_coredump(long signr, int exit_code, struct pt_regs * regs)
 fail_unlock:
 	complete_all(&mm->core_done);
 fail:
-	unlock_kernel();
 	return retval;
 }