Re: [PATCH v2 17/20] doc: Add IP provider documentation
Kris Van Hees <[email protected]>
| Newsgroups | dev.linux.lists.dtrace |
|---|---|
| Message-ID | <[email protected]> |
On Thu, Oct 09, 2025 at 05:00:06PM -0400, Eugene Loh wrote: > Hmm, just to clarify... you mean pull this patch out of the patch series so > that it can be applied independently of the other fixes? Ah yes, I didn't realize it was part of the 20-patch series. I think it was an independent patch in its v1 form? If so, I prpbably was thinking about that. OK - let's keep it as part of the series and it will go in with it. > On 10/9/25 13:03, Kris Van Hees wrote: > > This patch does not apply cleanly to dev-queue. Can you look into that and > > post a v3 (keeping the R-b)? > > > > On Fri, Sep 26, 2025 at 03:05:54PM -0400, [email protected] wrote: > > > From: Eugene Loh <[email protected]> > > > > > > Signed-off-by: Eugene Loh <[email protected]> > > > Reviewed-by: Alan Maguire <[email protected]> > > > --- > > > doc/userguide/index.md | 10 + > > > doc/userguide/reference/dtrace_providers.md | 2 + > > > .../reference/dtrace_providers_ip.md | 174 ++++++++++++++++++ > > > 3 files changed, 186 insertions(+) > > > create mode 100644 doc/userguide/reference/dtrace_providers_ip.md > > > > > > diff --git a/doc/userguide/index.md b/doc/userguide/index.md > > > index f3d96a4d6..18b9bcd68 100644 > > > --- a/doc/userguide/index.md > > > +++ b/doc/userguide/index.md > > > @@ -208,6 +208,16 @@ > > > - [fileinfo\_t](reference/dtrace_providers_io.md#fileinfo_t) > > > - [io Examples](reference/dtrace_providers_io.md#io-examples) > > > - [io Stability](reference/dtrace_providers_io.md#io-stability) > > > + - [IP Provider](reference/dtrace_providers_ip.md) > > > + - [ip Probes](reference/dtrace_providers_ip.md#ip-probes) > > > + - [ip Probe Arguments](reference/dtrace_providers_ip.md#ip-probe-arguments) > > > + - [pktinfo\_t](reference/dtrace_providers_ip.md#pktinfo_t) > > > + - [csinfo\_t](reference/dtrace_providers_ip.md#csinfo_t) > > > + - [ipinfo\_t](reference/dtrace_providers_ip.md#ipinfo_t) > > > + - [ifinfo\_t](reference/dtrace_providers_ip.md#ifinfo_t) > > > + - [ipv4info\_t](reference/dtrace_providers_ip.md#ipv4info_t) > > > + - [ipv6info\_t](reference/dtrace_providers_ip.md#ipv6info_t) > > > + - [ip Stability](reference/dtrace_providers_ip.md#ip-stability) > > > - [Lockstat Provider](reference/dtrace_providers_lockstat.md) > > > - [lockstat Probes](reference/dtrace_providers_lockstat.md#lockstat-probes) > > > - [lockstat Probe Arguments](reference/dtrace_providers_lockstat.md#lockstat-probe-arguments) > > > diff --git a/doc/userguide/reference/dtrace_providers.md b/doc/userguide/reference/dtrace_providers.md > > > index 9f64935c6..54a018d5c 100644 > > > --- a/doc/userguide/reference/dtrace_providers.md > > > +++ b/doc/userguide/reference/dtrace_providers.md > > > @@ -11,6 +11,8 @@ The `dtrace` provider includes several probes that are specific to DTrace itself > > > The `fbt` \(Function Boundary Tracing\) provider includes probes that are associated with the entry to and return from most functions in the Linux kernel. Therefore, there could be tens of thousands of `fbt` probes. > > > - **[IO Provider](../reference/dtrace_providers_io.md)** > > > The `io` provider makes available probes that relate to data input and output. > > > +- **[IP Provider](../reference/dtrace_providers_ip.md)** > > > +The `ip` provider provides probes that can be used to study IP traffic. > > > - **[Lockstat Provider](../reference/dtrace_providers_lockstat.md)** > > > The `lockstat` provider provides probes that can be used to study lock usage and contention. > > > - **[Pid Provider](../reference/dtrace_providers_pid.md)** > > > diff --git a/doc/userguide/reference/dtrace_providers_ip.md b/doc/userguide/reference/dtrace_providers_ip.md > > > new file mode 100644 > > > index 000000000..4e6c47fb2 > > > --- /dev/null > > > +++ b/doc/userguide/reference/dtrace_providers_ip.md > > > @@ -0,0 +1,174 @@ > > > + > > > +# IP Provider > > > + > > > +The `ip` provider makes available a probe at IP send operations in the system and a probe at receive. > > > + > > > +**Parent topic:**[DTrace Provider Reference](../reference/dtrace_providers.md) > > > + > > > +## ip Probes > > > + > > > +The `ip` provider provides one probe for IP sends and another for IP receives. > > > +The module name is always `vmlinux` and the function name is empty. > > > + > > > +## ip Probe Arguments > > > + > > > +The following table lists the argument types for both the `send` and `receive` probes. > > > + > > > +| arg | type | > > > +| :--- | :--- | > > > +| `args[0]` | `pktinfo_t *` | > > > +| `args[1]` | `csinfo_t *` | > > > +| `args[2]` | `ipinfo_t *` | > > > +| `args[3]` | `ifinfo_t *` | > > > +| `args[4]` | `ipv4info_t *` | > > > +| `args[5]` | `ipv6sinfo_t *` | > > > + > > > +### pktinfo\_t > > > + > > > +The `pktinfo_t` structure is an abstraction that describes a packet. > > > +Detailed information about this data structure can be found in > > > +`/usr/lib64/dtrace/*version*/ip.d` or > > > +`/usr/lib64/dtrace/*version*/net.d`, depending on `dtrace` version. > > > +The definition of `pktinfo_t` is as follows: > > > + > > > +```nocopybutton > > > +typedef struct pktinfo { > > > + uintptr_t pkt_addr; > > > +} pktinfo_t; > > > +``` > > > + > > > +**Note:** > > > + > > > +DTrace translates the members of `pktinfo_t` from the `struct sk_buff *`. > > > + > > > +### csinfo\_t > > > + > > > +The `csinfo_t` structure is an abstraction that describes connection state. > > > +Detailed information about this data structure can be found in > > > +`/usr/lib64/dtrace/*version*/ip.d` or > > > +`/usr/lib64/dtrace/*version*/net.d`, depending on `dtrace` version. > > > +The definition of `csinfo_t` is as follows: > > > + > > > +```nocopybutton > > > +typedef struct csinfo { > > > + uintptr_t cs_addr; > > > + uint64_t cs_cid; > > > +} csinfo_t; > > > +``` > > > + > > > +**Note:** > > > + > > > +DTrace translates the members of `csinfo_t` from the `struct sock *`. > > > + > > > +### ipinfo\_t > > > + > > > +The `ipinfo_t` structure contains common IP info for both IPv4 and IPv6. > > > +Detailed information about this data structure can be found in `/usr/lib64/dtrace/*version*/ip.d`. > > > +The definition of `ipinfo_t` is as follows: > > > + > > > +```nocopybutton > > > +typedef struct ipinfo { > > > + uint8_t ip_ver; /* IP version (4, 6) */ > > > + uint32_t ip_plength; /* payload length */ > > > + string ip_saddr; /* source address */ > > > + string ip_daddr; /* destination address */ > > > +} ipinfo_t; > > > +``` > > > + > > > +**Note:** > > > + > > > +DTrace translates the members of `ipinfo_t` from, variously, > > > +`struct iphdr *`, `struct ipv6hdr *`, or `void_ip_t *`. > > > + > > > +### ifinfo\_t > > > + > > > +The `ifinfo_t` structure contains network interface info. > > > +Detailed information about this data structure can be found in `/usr/lib64/dtrace/*version*/ip.d`. > > > +The definition of `ifinfo_t` is as follows: > > > + > > > +```nocopybutton > > > +typedef struct ifinfo { > > > + string if_name; /* interface name */ > > > + int8_t if_local; /* is delivered locally */ > > > + netstackid_t if_ipstack; /* netns pointer on Linux */ > > > + uintptr_t if_addr; /* pointer to raw struct net_device */ > > > +} ifinfo_t; > > > +``` > > > + > > > +**Note:** > > > + > > > +DTrace translates the members of `ifinfo_t` from a `struct net_device *`. > > > + > > > +### ipv4info\_t > > > + > > > +The `ipv4info_t` structure is translated version of the IPv4 header > > > +(with raw pointer). > > > +These values are NULL if the packet is not IPv4. > > > +Detailed information about this data structure can be found in `/usr/lib64/dtrace/*version*/ip.d`. > > > +The definition of `ipv4info_t` is as follows: > > > + > > > +```nocopybutton > > > +typedef struct ipv4info { > > > + uint8_t ipv4_ver; /* IP version (4) */ > > > + uint8_t ipv4_ihl; /* header length, bytes */ > > > + uint8_t ipv4_tos; /* type of service field */ > > > + uint16_t ipv4_length; /* length (header + payload) */ > > > + uint16_t ipv4_ident; /* identification */ > > > + uint8_t ipv4_flags; /* IP flags */ > > > + uint16_t ipv4_offset; /* fragment offset */ > > > + uint8_t ipv4_ttl; /* time to live */ > > > + uint8_t ipv4_protocol; /* next level protocol */ > > > + string ipv4_protostr; /* next level protocol, as string */ > > > + uint16_t ipv4_checksum; /* header checksum */ > > > + ipaddr_t ipv4_src; /* source address */ > > > + ipaddr_t ipv4_dst; /* destination address */ > > > + string ipv4_saddr; /* source address, string */ > > > + string ipv4_daddr; /* destination address, string */ > > > + struct iphdr *ipv4_hdr; /* pointer to raw header */ > > > +} ipv4info_t; > > > +``` > > > + > > > +**Note:** > > > + > > > +DTrace translates the members of `ipv4info_t` from a `struct iphdr *`. > > > + > > > +### ipv6info\_t > > > + > > > +The `ipv6info_t` structure is translated version of the IPv6 header > > > +(with raw pointer). > > > +These values are NULL if the packet is not IPv6. > > > +Detailed information about this data structure can be found in `/usr/lib64/dtrace/*version*/ip.d`. > > > +The definition of `ipv6info_t` is as follows: > > > + > > > +```nocopybutton > > > +typedef struct ipv6info { > > > + uint8_t ipv6_ver; /* IP version (6) */ > > > + uint8_t ipv6_tclass; /* traffic class */ > > > + uint32_t ipv6_flow; /* flow label */ > > > + uint16_t ipv6_plen; /* payload length */ > > > + uint8_t ipv6_nexthdr; /* next header protocol */ > > > + string ipv6_nextstr; /* next header protocol, as string */ > > > + uint8_t ipv6_hlim; /* hop limit */ > > > + in6_addr_t *ipv6_src; /* source address */ > > > + in6_addr_t *ipv6_dst; /* destination address */ > > > + string ipv6_saddr; /* source address, string */ > > > + string ipv6_daddr; /* destination address, string */ > > > + struct ipv6hdr *ipv6_hdr; /* pointer to raw header */ > > > +} ipv6info_t; > > > +``` > > > + > > > +**Note:** > > > + > > > +DTrace translates the members of `ipv6info_t` from a `struct ipv6hdr *`. > > > + > > > +## ip Stability > > > + > > > +The `ip` provider uses DTrace's stability mechanism to describe its stabilities. These stability values are listed in the following table. > > > + > > > +| Element | Name Stability | Data Stability | Dependency Class | > > > +| :--- | :--- | :--- | :--- | > > > +| Provider | Evolving | Evolving | ISA | > > > +| Module | Private | Private | Unknown | > > > +| Function | Private | Private | Unknown | > > > +| Name | Evolving | Evolving | ISA | > > > +| Arguments | Evolving | Evolving | ISA | > > > -- > > > 2.47.3 > > >