| Poor-man's Ftrace is a live printk function tracer. It does not handle |
| concurrency well, whether that is interleaved IRQs or especially parallelism. |
| Everything gets printed at the same time, and shares the same global |
| indentation variable. Still, it works reasonably well for IRQs, ktasks, and |
| syscalls. |
| |
| Careful using this on certain devices in k/d/dev/, like acpi and console. One |
| of the devs locks up if you try to print. |
| |
| I usually turn off the 'print' bool in kdebug.c for booting, then turn it on |
| via 'kfunc toggle_print_func'. |
| |
| To spatch the networking code, try something like: |
| |
| $ for i in kern/src/net kern/drivers/net kern/drivers/dev/ether.c; do |
| spatch --sp-file scripts/spatch/poor-ftrace.cocci --in-place $i; done |