> Anyway, a slightly related/different question: > > Should that: > WRITE_ONCE(rp->rtort_pipe_count, rp->rtort_pipe_count + 1); > > Be: > WRITE_ONCE(rp->rtort_pipe_count, READ_ONCE(rp->rtort_pipe_count) + 1); > > ?
Hi, Joel. Sorry, I am not very sure about this. I do a little research on it. I looked through all code in kernel that looks like this, both kinds are used. I also try to compile this file with and without the READ_ONCE in WRITE_ONCE using gcc-9. Their binary is just the same. Thus I think in the current compiler version, they do not have a big difference, but if the compiler wants to optimize more, maybe the latter one is better.
