Each live discussion section is conducted by a TA. Below is a list showing which TA is responsible for which discussion section:

• Fri 10:00am - 10:50am OHE 132, lead by Zhuojin Li (live discussion can be accessed via D2L)
• Fri 12:00pm - 12:50pm SOS B46, lead by Zhuojin Li (live discussion can be accessed via Zoom)

During a live discussion section, the TA will answer questions about the pre-recorded video and answer your questions about programming assignments. If you have a particular topic that you would like the TA to discuss in class (including stuff like something covered in lectures that you would like the TA to explain further), you should send email to the TA before 6PM on Thursday. The TA will try his/her best to cover such requests.

Please note that programming assignments are due on Fridays. Since you are expected to have finished the an assignment before its due date, on the due date of a programming assignment, the TA will be focusing on the next programming assignment and that takes priority over the current assignment. If there is time left, the TA can discuss the current assignment.

To download all the PDF and text files below in one command, do the following inside a terminal in Ubuntu 16.04:

    wget -r -l 1 --user=USERID --password=PASSWORD http://merlot.usc.edu/cs402-f24/discussions.html

where USERID and PASSWORD are the user ID and password used to access protected content from our class web site. But please note that the slides can change at any time without notice. Therefore, it's a good idea to re-run the above command often to synchroniza your copy with the server!

Recordings of the Friday live discussion sections are posted in Lecture Slides & Videos.

The following are tentative discussion section slides (in PDF and TXT formats) for this semester.

Please note that the source code below is for the purpose of discussions and may not be identical to the code in your assignments. It would be a really bad idea (because you can lose a lot of points) to replace the code in your assignments with the code here! So, please do not replace the code in your assignments with the code here.

• Week 1 (PDF) - gdb, warmup #1

  Demo (for live discussion section):

  • linux-demo.txt
  • hello.c
  • crash.c
  • gdb-demo.txt

• Week 2 (PDF) - parsing text input in C, Unix/Linux commands
• Week 3 (PDF) - introduction to warmup #2
• Week 4 (PDF) - warmup #2 (catching SIGINT and pthread cancellation), introduction to kernel assignments (part 1)

  Code in slides:

  • defs.h
  • fork-wait.c
  • cat.c
  • redirect.c
  • thr-term.c
  • busywait.c
  • join.c
  • deadlock.c
  • trylock.c
  • whoopee.c
  • status-update.c
  • sigblock.c
  • sigwait.c
  • direct.c
  • cancel.c
  • three-threads.c

• Week 5 (PDF) - introduction to kernel assignments (part 2)
• Week 6 (PDF) - kernel 1, kmain.c, kmain_aux.c

  Code in slides:

  • kmain.c
  • kmain_aux.c

  Code (kernel)

  • kmain.c

• Week 7 (PDF) - more on kernel 1, faber_test.c

  Code (kernel)

  • faber_test.c

• Week 8 (PDF) - introduction to kernel 2

  Code (kernel):

  • namev.c (path name resolution code)

• Week 9 (TXT) - kernel 2 polymorphism, vfs.c, vnode.c, vn_special.c, file.c, vfs_syscall.c, vn_mmobj_ops.c, ramfs.c, vfstest.c, faber_fs_test

  Code (kernel):

  • vfs.c
  • vnode.c
  • vn_special.c
  • file.c
  • vfs_syscall.c
  • vn_mmobj_ops.c
  • ramfs.c (also look for any "_ops_t" in "kernel/include/fs/*.h", "kernel/fs/*.c" and "kernel/fs/ramfs/*.c")
  • vfstest.c
  • faber_fs_test.c

• Week 10 (PDF) - introduction to kernel 3, the elf32 loader

  Code (kernel):

  • elf32.c - the elf32 loader
  • exec.c
  • access.c

• Week 11 (PDF) - more on kernel 3, address space implementation (vmarea, mmobj, pframe, page table)

  Code (kernel):

  • vn_mmobj_ops.c - code for the mmobj inside a vnode
  • syscall.c (in the kernel)

  
  Code (user):

  • syscall.c (in the libc user space library)

  
  Kernel 3 FAQ:

  • meaning of pagenum

• Week 12 (TXT) - objdump, page fault handling, hello

  Code (kernel):

  • pagefault.c
  • syscall.c (in the kernel)
  • vn_mmobj_ops.c - code for the mmobj inside a vnode

  
  Code (user):

  • hello.c
  • syscall.c (in the libc user space library)

  
  Kernel 3 FAQ:

  • handle the first page fault
  • meaning of pagenum
  • page faults

  
  Useful Linux commands:

      objdump --disassemble --section=".text" user/usr/bin/hello.exec
      objdump --disassemble --section=".text" -S user/usr/bin/hello.exec
      objdump --headers user/usr/bin/hello.exec
      xxd -g 1 user/usr/bin/hello.exec

  Useful GDB commands:

      add-symbol-file user/usr/bin/hello.exec 0x08048094
      b __libc_static_entry
      b main
      b *0x12345678
      layout asm
      layout next
      si
      info registers
      kernel info vmmap_mapping_info curproc->p_vmmap

• Week 13 (TXT) - fork(), user space shell

  Code (user):

  • fork-and-wait.c
  • /sbin/init.c

  
  Kernel 3 FAQ:

  • do_fork()
  • "/sbin/init" not working

  Remaining user space programs:

  Code (user):

  • memtest.c
  • eatmem.c
  • forkbomb.c

  
  Kernel 3 FAQ:

  • dynamic region and do_brk()
  • make forkbomb run forever

• Week 14 - (no discussion section this week)
• Week 15 - (no discussion section this week)

Below is the tentative quiz schedule for this semester.

Week #		Quiz #		Dates		Coverage
1		Quiz 0		8/30		Lectures 1/2, Week 1 discussion
2		Quiz 1		9/6		Lectures 3/4, Week 2 discussion
3		-		9/13		no quiz (warmup1 due on Fri)
4		Quiz 2		9/20		Lectures 5/6/7/8, Weeks 3/4 discussion
5		Quiz 3		9/27		Lectures 9/10, Week 5 discussion
6		-		10/4		no quiz (warmup2 due on Fri)
7		-		10/11		no quiz (Fall recess on Fri)
8		Quiz 4		10/18		Lectures 11/12/13/14/15/16, Weeks 6/7 discussion
9		-		10/25		no quiz (kernel1 due on Fri)
10		-		11/1		no quiz (midterm on Wed)
11		Quiz 5		11/8		Lectures 17/18/19/20, Week 8/9 discussion
12		-		11/15		no quiz (kernel2 due on Fri)
13		Quiz 6		11/22		Lectures 21/22/23/24, Weeks 10/11 discussions
14		-		11/29		no quiz (Thanksgiving)
15		-		12/6		no quiz (kernel3 due on Fri)