litex/migen/flow/perftools.py

from migen.flow.hooks import *

class EndpointReporter(EndpointSimHook):
    def __init__(self, endpoint):
        EndpointSimHook.__init__(self, endpoint)
        self.reset()

    def reset(self):
        self.inactive = 0
        self.ack = 0
        self.nack = 0

    # Total number of cycles per token (inverse token rate)
    def cpt(self):
        return (self.inactive + self.nack + self.ack)/self.ack

    # Inactivity cycles per token (slack)
    def ipt(self):
        return self.inactive/self.ack

    # NAK cycles per token (backpressure)
    def npt(self):
        return self.nack/self.ack

    def report_str(self):
        if self.ack:
            return "C/T={:.2f}\nI/T={:.2f}\nN/T={:.2f}".format(self.cpt(), self.ipt(), self.npt())
        else:
            return "N/A"

    def on_ack(self):
        self.ack += 1

    def on_nack(self):
        self.nack += 1

    def on_inactive(self):
        self.inactive += 1

class DFGReporter(DFGHook):
    def __init__(self, dfg):
        DFGHook.__init__(self, dfg, lambda u, ep, v: EndpointReporter(getattr(u, ep)))

    def get_edge_labels(self):
        d = dict()
        for (u, v), eps in self.nodepair_to_ep.items():
            if len(eps) == 1:
                d[(u, v)] = list(eps.values())[0].report_str()
            else:
                d[(u, v)] = "\n".join(ep + ":\n" + reporter.report_str()
                    for ep, reporter in eps)
        return d