[QUESTION] BPF trampoline limits

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Hello! If I can I would like to ask one question about the BPF
trampoline. Reading the description of this commit [0] I noticed the
following statement:

- Detach of a BPF program from the trampoline should not fail. To avoid memory
allocation in detach path the half of the page is used as a reserve and flipped
after each attach/detach. 2k bytes is enough to call 40+ BPF programs directly
which is enough for BPF tracing use cases. This limit can be increased in the
future.

Looking at the kernel code, I found only this limit
BPF_MAX_TRAMP_LINKS. If I understood correctly, this limit denies us
the use of the same trampoline for more than 38 bpf programs. So my
question is, does the commit description refer to another limit or
does this "call 40+ BPF programs" refer to the BPF_MAX_TRAMP_LINKS
macro?

Thank you in advance for your time,
Andrea

0: https://github.com/torvalds/linux/commit/fec56f5890d93fc2ed74166c397dc186b1c25951



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