Debug tricks

# b9e416502121 => docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
b9e416502121 ubuntu23-cs144 "/bin/bash" 13 hours ago Up 13 hours hardcore_wescoff
c1b373cdc67a ubuntu23-cs144 "/bin/bash" 27 hours ago Up 17 hours reverent_maxwell


# Start Kernel
make qemu-gdb

gdb-multiarch kernel/kernel

set architecture riscv:rv64

target remote localhost:25000

# split-screen
layout split

# Start Kernel
pintos --qemu --gdb --run user_program_name
----
# Find the function you want to Debug, for example
grep -rn "timer_sleep"
...tests/threads/alarm-simultaneous.c:90: timer_sleep (sleep_until - timer_ticks ());
tests/threads/mlfqs-fair.c:101: timer_sleep (40 * TIMER_FREQ);
tests/threads/mlfqs-fair.c:116: timer_sleep (sleep_time - timer_elapsed (ti->start_time));
grep: threads/build/tests/threads/alarm-zero.o: binary file matches
grep: threads/build/tests/threads/alarm-simultaneous.o: binary file matches
grep: threads/build/tests/threads/mlfqs-fair.o: binary file matches
# We choose one arbitrarily, for example, alarm-zero

pintos --qemu --gdb -- run alarm-zero

---- cd build

# Enter gdb

pintos-gdb kernel.o

(gdb)set architecture i386

(gdb)target remote localhost:1234

# For Example

(gdb)break devices/timer.c:96

(gdb)c

(gdb)step...

# If qemu freezes, execute this to find the PID

ps aux | grep qemu

root 32 0.0 0.0 288508 5640 pts/1 S+ 03:51 0:00 make qemu-gdb

root 53 0.5 2.4 2016128 194744 pts/1 Sl+ 03:51 0:07 qemu-system-riscv64 -machine virt -bios none -kernel kernel/kernel -m 128M -smp 3 -nographic -global virtio-mmio.force-legacy=false -drive file=fs.img,if=none,format=raw,id=x0 -device virtio-blk-device,drive=x0,bus=virtio-mmio-bus.0 -S -gdb tcp::25000

root 84 60.0 0.0 288516 4704 pts/2 S+ 04:14 0:00 grep --color=auto qemu

# kill process

kill -9 32 53

pintos --qemu --run alarm-multiple

# Set breakpoint

break filename:line

# For Example

break devices/timer.c:92

# Continue running the program until the next breakpoint

continue | c

# Step through the code, entering the function

step | s

# Step through the code, but do not enter the function

next | n

# Execute the current function and return to the calling function

finish

# Run to the specified line number

until <line>

# Jump directly to the specified line number

jump <line>

# List all breakpoints

info breakpoints

# Display the contents of all registers

info registers

# Display the current stack

info frame

# Display all threads

info threads

# Display all variables in the current function

info locals

# Delete a breakpoint

delete <breakpoint_number>

# Print the variable value

print <variable>

# Display the current program code

list | l

# Display the current function call stack

backtrace | bt

# Quit

#ubuntu/debian
apt install diffstat

#Macos
brew install diffstat

# For Example
git diff | diffstat

#Commit
git show <commit_id> | diffstat
# Or
git diff <old_commit> <new_commit> | diffstat

# Git diff
git diff --stat