"objfollow" not "objtrace"

[chensong2000]

instead of searching the function arguments for "obj", we should just
read the obj value at every function and report when it changed,

cat-117 [002] ...2. 1.602245: bio_add_page <-ext4_mpage_readpages object:0xffff88811bee4000 value:0x2000 (last value:0x1000 at [002] __bio_add_page <-bio_add_page ts: 1.602245)

? you can't really trust the arguments
are what you are tracing. I would hold off on that until we have a good BTF
tracing infrastructure in the function tracer.

https://lore.kernel.org/all/20221017154057.78babf40@gandalf.local.home/

[chensong2000]

you can't really trust the arguments， why？
until we have a good BTF tracing infrastructure怎么理解