read problem using bpf in freebsd kernel...

[perumal conf]

Hi all,
   I hope, someone will clarify my doubt regarding reading/writing raw ethernet packets using BPF in freeBsd kernel.
   Through BPF, We can read packets from driver. If we are receiving more number of packets at the driver level, the actual step involves reading the packet and processing and issuing again the request for reading.  There will be some delay between subsequent reads because of packet processing.  Because of this delay, some packets are getting overwritten at the driver level before the next read request from the bpf.  Because of this i am missing some of the received packets.  What should be the approach to avoid this situation?

thanks in advance
perumal.