Add a document describing the padata interface

This originally appeared as http://lwn.net/Articles/382257/.

Cc: Steffen Klassert <[email protected]>
Signed-off-by: Jonathan Corbet <[email protected]>
diff --git a/Documentation/00-INDEX b/Documentation/00-INDEX
index 06b982af..dd10b51 100644
--- a/Documentation/00-INDEX
+++ b/Documentation/00-INDEX
@@ -250,6 +250,8 @@
 	- info on how to read Numa policy hit/miss statistics in sysfs.
 oops-tracing.txt
 	- how to decode those nasty internal kernel error dump messages.
+padata.txt
+	- An introduction to the "padata" parallel execution API
 parisc/
 	- directory with info on using Linux on PA-RISC architecture.
 parport.txt