> 1. IPC fastpath can apply in seL4_Call and seL4_Reply_Recv, is it right?
> seL4_Send, seL4_Recv can't apply IPC fastpath.
Yes. We could add fastpaths for other paths if required but they do not currently exist.
which would only happen if there was a convincing use case, which I haven’t seen yet. seL4_Send and seL4_Recv are meant to be used for setting up connections, not for performance-critical stuff.