[PATCH] x86: all cpu backtrace
When a spinlock lockup occurs, arrange for the NMI code to emit an all-cpu
backtrace, so we get to see which CPU is holding the lock, and where.
Cc: Andi Kleen <ak@muc.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Andi Kleen <ak@suse.de>
diff --git a/lib/spinlock_debug.c b/lib/spinlock_debug.c
index b6c4f89..479fd46 100644
--- a/lib/spinlock_debug.c
+++ b/lib/spinlock_debug.c
@@ -7,6 +7,7 @@
*/
#include <linux/spinlock.h>
+#include <linux/nmi.h>
#include <linux/interrupt.h>
#include <linux/debug_locks.h>
#include <linux/delay.h>
@@ -117,6 +118,9 @@
raw_smp_processor_id(), current->comm,
current->pid, lock);
dump_stack();
+#ifdef CONFIG_SMP
+ trigger_all_cpu_backtrace();
+#endif
}
}
}