X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=doc%2Fthreads.texi;h=1905707ffa09a631d2a7114febf6472438b52d93;hb=18654de05aa2c2fa2cc63e2c9c30b9dc536a33d7;hp=dae47bb908a2fb87430c114e39efe15246e00c1f;hpb=19df3c4b3fe74917695b4557f98393fbf35193e9;p=pintos-anon

diff --git a/doc/threads.texi b/doc/threads.texi
index dae47bb..1905707 100644
--- a/doc/threads.texi
+++ b/doc/threads.texi
@@ -157,9 +157,9 @@ the kernel.
 Basic interrupt handling and functions for turning interrupts on and
 off.
 
-@item intr-stubs.pl
+@item intr-stubs.S
 @itemx intr-stubs.h
-A Perl program that outputs assembly for low-level interrupt handling.
+Assembly code for low-level interrupt handling.
 
 @item synch.c
 @itemx synch.h
@@ -487,7 +487,10 @@ exited at the time of the later joins.  Thus, joins on T after the
 first should return immediately.
 
 Calling @func{thread_join} on an thread that is not the caller's
-child should cause the caller to return immediately.
+child should cause the caller to return immediately.  For this purpose,
+children are not inherited, that is, if @var{A} has child @var{B} and
+@var{B} has child @var{C}, then @var{A} always returns immediately
+should it try to join @var{C}, even if @var{B} is dead.
 
 Consider all the ways a join can occur: nested joins (@var{A} joins
 @var{B}, then @var{B} joins @var{C}), multiple joins (@var{A} joins
@@ -495,15 +498,10 @@ Consider all the ways a join can occur: nested joins (@var{A} joins
 if @func{thread_join} is called on a thread that has not yet been
 scheduled for the first time?  You should handle all of these cases.
 Write test code that demonstrates the cases your join works for.
-Don't overdo the output volume, please!
 
 Be careful to program this function correctly.  You will need its
 functionality for project 2.
 
-Once you've implemented @func{thread_join}, define
-@code{THREAD_JOIN_IMPLEMENTED} in @file{constants.h}.
-@xref{Conditional Compilation}, for more information.
-
 @node Problem 1-3 Priority Scheduling
 @section Problem 1-3: Priority Scheduling
 
@@ -527,7 +525,9 @@ than the currently running thread, the current thread should
 immediately yield the processor to the new thread.  Similarly, when
 threads are waiting for a lock, semaphore or condition variable, the
 highest priority waiting thread should be woken up first.  A thread
-may set its priority at any time.
+may raise or lower its own priority at any time, but lowering its
+priority such that it no longer has the highest priority must cause it
+to immediately yield the CPU.
 
 One issue with priority scheduling is ``priority inversion'': if a
 high priority thread needs to wait for a low priority thread (for
@@ -555,10 +555,6 @@ implement this fix for semaphores, condition variables, or joins,
 although you are welcome to do so.  However, you do need to implement
 priority scheduling in all cases.
 
-You may assume a static priority for priority donation, that is, it is
-not necessary to ``re-donate'' a thread's priority if it changes
-(although you are free to do so).
-
 @node Problem 1-4 Advanced Scheduler
 @section Problem 1-4: Advanced Scheduler