panic: add cpu/pid to warn_slowpath_common in WARNING printk()s

Add the cpu/pid that called WARN() so that the stack traces can be
matched up with the WARNING messages.

[akpm@linux-foundation.org: remove stray quote]
Signed-off-by: Alex Thorlton <athorlton@sgi.com>
Reviewed-by: Robin Holt <holt@sgi.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Vikram Mulukutla <markivx@codeaurora.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/panic.c b/kernel/panic.c
index 167ec097..9771231 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -399,8 +399,9 @@
 static void warn_slowpath_common(const char *file, int line, void *caller,
 				 unsigned taint, struct slowpath_args *args)
 {
-	printk(KERN_WARNING "------------[ cut here ]------------\n");
-	printk(KERN_WARNING "WARNING: at %s:%d %pS()\n", file, line, caller);
+	pr_warn("------------[ cut here ]------------\n");
+	pr_warn("WARNING: CPU: %d PID: %d at %s:%d %pS()\n",
+		raw_smp_processor_id(), current->pid, file, line, caller);
 
 	if (args)
 		vprintk(args->fmt, args->args);