X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=TODO;h=9825200fed911631d245c7fa0048ee61476789fb;hb=dd07a992c428c400a35f132a418b2b4bb2301e6a;hp=30f324682f09fc10a05eacd400ad8f1fa1ae6422;hpb=ff076af15fa93292b8843e76bd6bab7ac5421095;p=pintos-anon

diff --git a/TODO b/TODO
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+++ b/TODO
@@ -1,30 +1,101 @@
 -*- text -*-
 
-* The p1-4.c testcase needs significant tuning.  Currently it takes
-  too long (especially when SHOW_PROGRESS is turned on) and doesn't
-  show significant improvement.
+* The tests in tests/ don't apply the grading patches.
 
-* The semantics of the join system call should change so that it only
-  returns the exit code once.
+* We need better example programs.
 
-* mmap/munmap should use segment IDs like Nachos.  Too hard otherwise.
+  - Need an mmap example program as a replacement for the crappy mmap FAQ
+    question.
 
-* Some confusion--do we really get overlapping ro/rw segment in normal
-  link?  Student example seemed to show that we don't.
+* Threads:
 
-* Finish writing the tour.
+  - join-invalid doesn't compile if tid_t is not scalar type.
 
-* Come up with a way for us to release some of the tests.
+  - mlfqs tests suck.  They aren't even correct, e.g. the amarv
+    submission from win0405 is graded incorrectly.
 
-* userprog project should mark read-only pages as actually read-only
-  in the page table
+* Userprog project:
 
-* Add src/testcases/vm, src/testcases/filesys and make it clear to use
-  them?
+  - Don't emphasize that stuff needs to be copied from user space to
+    kernel space.  Instead, emphasize validation and suggest that
+    copying is a common solution and that it will be necessary in
+    project 3 and in real OSes.  Also revise the grading criteria to
+    match.
 
-* Speed up disk routines: filling an 8 MB disk takes a long time.
+  - Move `join' implementation here, from `threads' project, to help
+    normalize the project difficulties.
 
-* Not sure that raw arc4 should really be used so much in the tests.
-  Any reason not to use random_bytes()?
+  - The semantics of the join system call should change so that it
+    only returns the exit code once.
+
+  - Mark read-only pages as actually read-only in the page table.  Or,
+    since this was consistently rated as the easiest project by the
+    students, require them to do it.
+
+  - Don't provide per-process pagedir implementation but only
+    single-process implementation and require students to implement
+    the separation?  This project was rated as the easiest after all.
+    Alternately we could just remove the synchronization on pid
+    selection and check that students fix it.
+
+* VM project:
+
+  - Discuss the perils of mixing dirty bits between kernel and user virtual
+    memory.
+
+  - Sample solution.
+
+  - Update grading/vm to reflect new mmap, munmap forms.
+
+* Filesys project:
+
+  - Increase maximum disk size from 8 MB to something that actually
+    requires doubly indirect nodes.  There is a negative pressure here
+    from the bitmap object--perhaps we need a specialized bitmap that
+    doesn't have to be all in-memory at once.
+
+    Alternatively, shrink the inode size.
+
+  - Add mkdir and ls example user programs.
+
+  - Add option to disable buffer cache.
+
+  - Get rid of "dump" commands--they're not really useful.
+
+  - Sample solution.
+
+* Documentation:
+
+  - Finish writing tour.
+
+  - Add "Digging Deeper" sections that describe the nitty-gritty x86
+    details for the benefit of those interested.
+
+  - Add explanations of what "real" OSes do to give students some
+    perspective.
+
+* Assignments:
+
+  - Add extra credit:
+
+    . Low-level x86 stuff, like paged page tables.
+
+    . Specifics on how to implement sbrk, malloc.
+
+    . Other good ideas.
+
+  - Add src/testcases/vm, src/testcases/filesys and make it clear to use
+    them?
+
+* Tests:
+
+  - Release some of them.
+
+  - The threads, userprog, vm test source files could use
+    factorization and cleanup along the lines of fslib in the filesys
+    tests.
+
+  - The p1-4.c testcase needs significant tuning.  Currently it takes
+    too long (especially when SHOW_PROGRESS is turned on) and doesn't
+    show significant improvement.
 
-* Grading script patches needed anymore?