Re: missing SDT_PROVIDER_DEFINE(sdt)

[Taylor R Campbell <campbell%mumble.net@localhost>]

   Date: Fri, 1 Apr 2016 12:29:19 +0900
   From: Kengo NAKAHARA <k-nakahara%iij.ad.jp@localhost>

   There is SDT_PROVIDER_DECLARE(sdt) in sdt.h.
       http://nxr.netbsd.org/xref/src/sys/sys/sdt.h#416
   However, there is no SDT_PROVIDER_DEFINE(sdt). I think this is
   inconsistent.

   Currently, "sdt" provider is not used yet, so this inconsistency doesn't
   cause problems. "sdt" provider will be used by ipf if it enable sdt.
   That is, when it enabled the following macros.
       http://nxr.netbsd.org/xref/src/sys/external/bsd/ipf/netinet/ip_compat.h#2831

   I think the following patch is required to prevent future problems such
   as ipf enabled sdt.

I'm actually a little puzzled by all that.  Why doesn't ipf just
define its own provider?  ipf appears to be the only use of the sdt
provider.  I'd sooner get rid of DTRACE_PROBE* altogether and just
adapt ipf to use its own provider.  But I have no objection if you'd
rather just add an SDT_PROVIDER_DEFINE(sdt).