X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=TODO;h=9825200fed911631d245c7fa0048ee61476789fb;hb=dd07a992c428c400a35f132a418b2b4bb2301e6a;hp=9e332a36a320dc0d4fc6b927d2e35a0e0737e3e7;hpb=c95f2f01e84c7579f3230ae82899c907de9a2526;p=pintos-anon diff --git a/TODO b/TODO index 9e332a3..9825200 100644 --- a/TODO +++ b/TODO @@ -1,20 +1,68 @@ -*- text -*- -* Code: +* The tests in tests/ don't apply the grading patches. - - Speed up disk routines: filling an 8 MB disk takes a long time. - (They're only slow because timer_sleep always waits for at least - one timer tick.) +* We need better example programs. - - userprog project should 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. + - Need an mmap example program as a replacement for the crappy mmap FAQ + question. - - For userprog project, 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. +* Threads: + + - join-invalid doesn't compile if tid_t is not scalar type. + + - mlfqs tests suck. They aren't even correct, e.g. the amarv + submission from win0405 is graded incorrectly. + +* Userprog project: + + - 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. + + - Move `join' implementation here, from `threads' project, to help + normalize the project difficulties. + + - 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: @@ -32,13 +80,9 @@ . Low-level x86 stuff, like paged page tables. - . Other good ideas. - - - The semantics of the join system call should change so that it - only returns the exit code once. + . Specifics on how to implement sbrk, malloc. - - mmap/munmap should use segment IDs like Nachos. Too hard - otherwise. + . Other good ideas. - Add src/testcases/vm, src/testcases/filesys and make it clear to use them?