[DTrace-devel] [PATCH v2 0/4] DTrace TCP provider

[Alan Maguire]

On 01/07/2025 20:27, Kris Van Hees wrote:
> On Tue, Jul 01, 2025 at 03:08:59PM -0400, Eugene Loh wrote:
>> Incidentally, looking at the subject lines for the patch series, I see:
>>
>>         dtrace: move get_member() to dt_cg.c
>>         dt_impl: bump number of TSLOTS to 8
>>         dtrace: add tcp provider
>>         dtrace: sync dlibs with tcp.d, ip.d and net.d changes
> 
> I would suggest:
> 
> 	cg: move get_member() to dt_cg.c
> 	cg: bump number of TSLOTS to 8
> 	tcp: new provider -or- Implement the tcp provider
> 	dlibs: sync dlibs with tcp.d, ip.d and net.d changes
>

perfect, thanks!

>> That is, each line is prefixed with a component name.  We do that a lot for
>> "test:", but otherwise the practice seems to depend on... the patch author? 
>> Anyhow, I claim "dtrace:" is not very useful.  For patch 1, all the prefix
>> is saying is "there is movement in the dtrace code base."  I think the
>> subject would be more direct without the prefix.  Same for patch 2.  For
>> patch 3, if one wanted to use a component prefix, I'd think one would use
>> "tcp:".
>>
>> Historically, it looks like we've added new providers with subject lines
>> like this:
>>
>>     rawfbt: new provider
>>     Implement the io provider
>>     Implement the ip provider
>>     Implement the lockstat provider
>>     Implement the sched provider (first part)
>>     Implement the proc provider
>>     provider: Implement a rawtp provider
>>     Add a CPC provider
>>     PID provider implementation
>>     Add a profile provider
>>     Implement BEGIN and END probes for the dtrace provider
>>     Added IO provider support for 4.14 kernels
>>
>> Everyone has their own style.  Shrug.  No big deal.
>>
>> Anyhow, personally, I think the prefixes don't add much, especially for
>> "dtrace:".  My suggestion is to drop the prefixes, but... your call.
>>
>> On 6/10/25 09:58, Alan Maguire wrote:
>>
>>> This series is a first draft of TCP provider support, where the
>>> probes are implemented via underlying fbt and sdt probes.
>>>
>>> Due to the use of the sock/inet_sock_set_state tracepoint, intended
>>> for ~5.15 kernels and later.  Tried replacing this with
>>>
>>> fbt::tcp_set_state:entry
>>>
>>> but this misses a few state transitions, so stuck with using
>>> the tracepoint.
>>>
>>> All tests under test/unittest/tcp pass unmodified on an upstream
>>> (6.15) kernel and 5.15 UEK7U3 kernel.
>>>
>>> It implements all documented TCP provider probes:
>>>
>>> accept-established, accept-refused, connnect-request,
>>> connect-established, connect-refused, receive, send,
>>> state-change
>>>
>>> Changes since RFC:
>>>
>>> - fixed issues with test failures on UEK7 due to missing
>>>    SYN_RCV state change
>>> - moved get_member() to dt_cg.c (patch 1)
>>>
>>> Alan Maguire (4):
>>>    dtrace: move get_member() to dt_cg.c
>>>    dt_impl: bump number of TSLOTS to 8
>>>    dtrace: add tcp provider
>>>    dtrace: sync dlibs with tcp.d, ip.d and net.d changes
>>>
>>>   dlibs/aarch64/5.14/ip.d  |   1 -
>>>   dlibs/aarch64/5.14/net.d |   6 +-
>>>   dlibs/aarch64/5.14/tcp.d |  52 ++---
>>>   dlibs/aarch64/5.16/ip.d  |   1 -
>>>   dlibs/aarch64/5.16/net.d |   6 +-
>>>   dlibs/aarch64/5.16/tcp.d |  52 ++---
>>>   dlibs/aarch64/6.1/ip.d   |   1 -
>>>   dlibs/aarch64/6.1/net.d  |   6 +-
>>>   dlibs/aarch64/6.1/tcp.d  |  52 ++---
>>>   dlibs/aarch64/6.10/ip.d  |   1 -
>>>   dlibs/aarch64/6.10/net.d |   6 +-
>>>   dlibs/aarch64/6.10/tcp.d |  52 ++---
>>>   dlibs/x86_64/5.14/ip.d   |   1 -
>>>   dlibs/x86_64/5.14/net.d  |   6 +-
>>>   dlibs/x86_64/5.14/tcp.d  |  52 ++---
>>>   dlibs/x86_64/5.16/ip.d   |   1 -
>>>   dlibs/x86_64/5.16/net.d  |   6 +-
>>>   dlibs/x86_64/5.16/tcp.d  |  52 ++---
>>>   dlibs/x86_64/6.1/ip.d    |   1 -
>>>   dlibs/x86_64/6.1/net.d   |   6 +-
>>>   dlibs/x86_64/6.1/tcp.d   |  52 ++---
>>>   dlibs/x86_64/6.10/ip.d   |   1 -
>>>   dlibs/x86_64/6.10/net.d  |   6 +-
>>>   dlibs/x86_64/6.10/tcp.d  |  52 ++---
>>>   libdtrace/Build          |   2 +
>>>   libdtrace/dt_cg.c        |  39 ++++
>>>   libdtrace/dt_cg.h        |   2 +
>>>   libdtrace/dt_impl.h      |   2 +-
>>>   libdtrace/dt_prov_ip.c   |  45 +----
>>>   libdtrace/dt_prov_tcp.c  | 405 +++++++++++++++++++++++++++++++++++++++
>>>   libdtrace/dt_provider.c  |   1 +
>>>   libdtrace/dt_provider.h  |   1 +
>>>   libdtrace/ip.d           |   1 -
>>>   libdtrace/net.d          |   6 +-
>>>   libdtrace/tcp.d          |  52 ++---
>>>   35 files changed, 761 insertions(+), 267 deletions(-)
>>>   create mode 100644 libdtrace/dt_prov_tcp.c
>>>