Note that struct file, struct dir are per-thread.

[pintos-anon] / doc / filesys.texi

diff --git a/doc/filesys.texi b/doc/filesys.texi
index 1605b2d9b88638fd36ae37a332de85e214120293..f245daa48ea1e6d592a86146ddddf9947ca9cffe 100644 (file)
--- a/doc/filesys.texi
+++ b/doc/filesys.texi
@@ -394,6 +394,10 @@ if B's data is all nonzero bytes, A is not allowed to see any zeros.
 Operations on different directories should take place concurrently.
 Operations on the same directory may wait for one another.
 
+Keep in mind that only data shared by multiple threads needs to be
+synchronized.  In the base file system, @struct{file} and @struct{dir}
+are accessed only by a single thread.
+
 @node Project 4 FAQ
 @section FAQ