X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;ds=sidebyside;f=TODO;h=1999f7033692229667ea30bb5df30aab22620b1b;hb=2655ee80b0014689c2d8fffcf67e4d6b1546b298;hp=ec8df9754fac7cb4a80fbf6aef12cd73848e9e25;hpb=8925763e88de77ae041d77082d7b8d00fb58c7d2;p=pintos-anon diff --git a/TODO b/TODO index ec8df97..1999f70 100644 --- a/TODO +++ b/TODO @@ -1,10 +1,99 @@ -*- 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. + + - Need an mmap example program as a replacement for the crappy mmap FAQ + question. + +* 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. + +* 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. -* mmap/munmap should use segment IDs like Nachos. Too hard otherwise.