Dtrace TCP Provider

Now that some of the hard work of getting 3.0 kernels working is out
of the way, I am now looking to add the TCP provider.

Heres the first very simple cut:

$ dtrace -l -P tcp
   ID   PROVIDER            MODULE                          FUNCTION NAME         48        tcp                                                     state-change
$ dtrace -P tcp
dtrace: description 'tcp' matched 1 probe

CPU     ID                    FUNCTION:NAME
  0     48                    :state-change
  0     48                    :state-change
  0     48                    :state-change
  0     48                    :state-change
...

It doesnt provide the arg0/arg1 values in the probe callback, but will
see what I can do.

Nigel just reported that the new release is better (thanks for the quick
feedback Nigel), but that this is showing a problem:

$ dtrace -n 'fbt:kernel:: BEGIN {exit(0);}'

On my kernel, it slowed down enormously, but after 60s of no RCU response,
the kernel just hangs. So, off to fix that.


Post created by CRiSP v10.0.17a-b6103