XDP hardware hints discussion mail archive
 help / color / mirror / Atom feed
From: Jesper Dangaard Brouer <brouer@redhat.com>
To: bpf@vger.kernel.org
Cc: Jesper Dangaard Brouer <brouer@redhat.com>,
	netdev@vger.kernel.org, xdp-hints@xdp-project.net,
	larysa.zaremba@intel.com, memxor@gmail.com,
	Lorenzo Bianconi <lorenzo@kernel.org>,
	mtahhan@redhat.com,
	Alexei Starovoitov <alexei.starovoitov@gmail.com>,
	Daniel Borkmann <borkmann@iogearbox.net>,
	Andrii Nakryiko <andrii.nakryiko@gmail.com>,
	dave@dtucker.co.uk, Magnus Karlsson <magnus.karlsson@intel.com>,
	bjorn@kernel.org
Subject: [xdp-hints] [PATCH RFCv2 bpf-next 10/18] btf: Add helper for kernel modules to lookup full BTF ID
Date: Wed, 07 Sep 2022 17:45:51 +0200	[thread overview]
Message-ID: <166256555117.1434226.17491394872817800182.stgit@firesoul> (raw)
In-Reply-To: <166256538687.1434226.15760041133601409770.stgit@firesoul>

NIC driver modules need to store the full BTF ID as the last member in
metadata area usually written as xdp_hints_common->btf_full_id.
This full BTF ID is a 64-bit value, encoding the modules own BTF object
ID as the high 32-bit and specific struct BTF type ID as lower 32-bit.

Drivers should invoke this once at init time and cache this BTF ID for
runtime usage.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 include/linux/btf.h |    1 +
 kernel/bpf/btf.c    |   23 +++++++++++++++++++++++
 2 files changed, 24 insertions(+)

diff --git a/include/linux/btf.h b/include/linux/btf.h
index a66266c00c04..b8f7c92b6767 100644
--- a/include/linux/btf.h
+++ b/include/linux/btf.h
@@ -150,6 +150,7 @@ bool btf_is_module(const struct btf *btf);
 struct module *btf_try_get_module(const struct btf *btf);
 struct btf *btf_get_module_btf(const struct module *module);
 void btf_put_module_btf(struct btf *btf);
+u64 btf_get_module_btf_full_id(struct btf *btf, const char *name);
 u32 btf_nr_types(const struct btf *btf);
 bool btf_member_is_reg_int(const struct btf *btf, const struct btf_type *s,
 			   const struct btf_member *m,
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 1e95391e0ca1..10a859943a49 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -7092,6 +7092,29 @@ struct btf *btf_get_module_btf(const struct module *module)
 }
 EXPORT_SYMBOL_GPL(btf_get_module_btf);
 
+u64 btf_get_module_btf_full_id(struct btf *btf, const char *name)
+{
+	s32 type_id;
+	u64 obj_id;
+
+	if (IS_ERR_OR_NULL(btf))
+		return 0;
+
+	obj_id  = btf_obj_id(btf);
+	type_id = btf_find_by_name_kind(btf, name, BTF_KIND_STRUCT);
+	if (type_id < 0) {
+		pr_warn("Module %s(ID:%d): BTF cannot find struct %s",
+			btf->name, (u32)obj_id, name);
+		return 0;
+	}
+
+	pr_info("Module %s(ID:%d): BTF type id %d for struct %s",
+		btf->name, (u32)obj_id, type_id, name);
+
+	return type_id | (obj_id << 32);
+}
+EXPORT_SYMBOL_GPL(btf_get_module_btf_full_id);
+
 BPF_CALL_4(bpf_btf_find_by_name_kind, char *, name, int, name_sz, u32, kind, int, flags)
 {
 	struct btf *btf = NULL;



  parent reply	other threads:[~2022-09-07 15:45 UTC|newest]

Thread overview: 57+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-09-07 15:45 [xdp-hints] [PATCH RFCv2 bpf-next 00/18] XDP-hints: XDP gaining access to HW offload hints via BTF Jesper Dangaard Brouer
2022-09-07 15:45 ` [xdp-hints] [PATCH RFCv2 bpf-next 01/18] libbpf: factor out BTF loading from load_module_btfs() Jesper Dangaard Brouer
2022-09-07 15:45 ` [xdp-hints] [PATCH RFCv2 bpf-next 02/18] libbpf: try to load vmlinux BTF from the kernel first Jesper Dangaard Brouer
2022-09-07 15:45 ` [xdp-hints] [PATCH RFCv2 bpf-next 03/18] libbpf: patch module BTF obj+type ID into BPF insns Jesper Dangaard Brouer
2022-09-07 15:45 ` [xdp-hints] [PATCH RFCv2 bpf-next 04/18] net: create xdp_hints_common and set functions Jesper Dangaard Brouer
2022-09-09 10:49   ` [xdp-hints] " Burakov, Anatoly
2022-09-09 14:13     ` Jesper Dangaard Brouer
2022-09-07 15:45 ` [xdp-hints] [PATCH RFCv2 bpf-next 05/18] net: add net_device feature flag for XDP-hints Jesper Dangaard Brouer
2022-09-07 15:45 ` [xdp-hints] [PATCH RFCv2 bpf-next 06/18] xdp: controlling XDP-hints from BPF-prog via helper Jesper Dangaard Brouer
2022-09-07 15:45 ` [xdp-hints] [PATCH RFCv2 bpf-next 07/18] i40e: Refactor i40e_ptp_rx_hwtstamp Jesper Dangaard Brouer
2022-09-07 15:45 ` [xdp-hints] [PATCH RFCv2 bpf-next 08/18] i40e: refactor i40e_rx_checksum with helper Jesper Dangaard Brouer
2022-09-07 15:45 ` [xdp-hints] [PATCH RFCv2 bpf-next 09/18] bpf: export btf functions for modules Jesper Dangaard Brouer
2022-09-07 15:45 ` Jesper Dangaard Brouer [this message]
2022-09-07 15:45 ` [xdp-hints] [PATCH RFCv2 bpf-next 11/18] i40e: add XDP-hints handling Jesper Dangaard Brouer
2022-09-07 15:46 ` [xdp-hints] [PATCH RFCv2 bpf-next 12/18] net: use XDP-hints in xdp_frame to SKB conversion Jesper Dangaard Brouer
2022-09-07 15:46 ` [xdp-hints] [PATCH RFCv2 bpf-next 13/18] mvneta: add XDP-hints support Jesper Dangaard Brouer
2022-09-07 15:46 ` [xdp-hints] [PATCH RFCv2 bpf-next 14/18] i40e: Add xdp_hints_union Jesper Dangaard Brouer
2022-09-07 15:46 ` [xdp-hints] [PATCH RFCv2 bpf-next 15/18] ixgbe: enable xdp-hints Jesper Dangaard Brouer
2022-09-07 15:46 ` [xdp-hints] [PATCH RFCv2 bpf-next 16/18] ixgbe: add rx timestamp xdp hints support Jesper Dangaard Brouer
2022-09-07 15:46 ` [xdp-hints] [PATCH RFCv2 bpf-next 17/18] xsk: AF_XDP xdp-hints support in desc options Jesper Dangaard Brouer
2022-09-08  8:06   ` [xdp-hints] " Magnus Karlsson
2022-09-08 10:10     ` Maryam Tahhan
2022-09-08 15:04       ` Jesper Dangaard Brouer
2022-09-09  6:43         ` Magnus Karlsson
2022-09-09  8:12           ` Maryam Tahhan
2022-09-09  9:42             ` Jesper Dangaard Brouer
2022-09-09 10:14               ` Magnus Karlsson
2022-09-09 12:35                 ` Jesper Dangaard Brouer
2022-09-09 12:44                   ` Magnus Karlsson
2022-09-07 15:46 ` [xdp-hints] [PATCH RFCv2 bpf-next 18/18] ixgbe: AF_XDP xdp-hints processing in ixgbe_clean_rx_irq_zc Jesper Dangaard Brouer
2022-09-08  9:30 ` [xdp-hints] Re: [PATCH RFCv2 bpf-next 00/18] XDP-hints: XDP gaining access to HW offload hints via BTF Alexander Lobakin
2022-09-09 13:48   ` Jesper Dangaard Brouer
2022-10-03 23:55 ` sdf
2022-10-04  9:29   ` Jesper Dangaard Brouer
2022-10-04 18:26     ` Stanislav Fomichev
2022-10-05  0:25       ` Martin KaFai Lau
2022-10-05  0:59         ` Jakub Kicinski
2022-10-05  1:02           ` Stanislav Fomichev
2022-10-05  1:24             ` Jakub Kicinski
2022-10-05  2:15               ` Stanislav Fomichev
2022-10-05 19:26                 ` Martin KaFai Lau
2022-10-06  9:14                   ` Magnus Karlsson
2022-10-06 15:29                     ` Jesper Dangaard Brouer
2022-10-11  6:29                       ` Martin KaFai Lau
2022-10-11 11:57                         ` Jesper Dangaard Brouer
2022-10-05 10:06             ` Toke Høiland-Jørgensen
2022-10-05 18:47               ` sdf
2022-10-06  8:19                 ` Maryam Tahhan
2022-10-06 17:22                   ` sdf
2022-10-05 14:19             ` Jesper Dangaard Brouer
2022-10-06 14:59               ` Jakub Kicinski
2022-10-05 13:43         ` Jesper Dangaard Brouer
2022-10-05 16:29       ` Jesper Dangaard Brouer
2022-10-05 18:43         ` sdf
2022-10-06 17:47           ` Jesper Dangaard Brouer
2022-10-07 15:05             ` David Ahern
2022-10-05 13:14     ` Burakov, Anatoly

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

  List information: https://lists.xdp-project.net/postorius/lists/xdp-hints.xdp-project.net/

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=166256555117.1434226.17491394872817800182.stgit@firesoul \
    --to=brouer@redhat.com \
    --cc=alexei.starovoitov@gmail.com \
    --cc=andrii.nakryiko@gmail.com \
    --cc=bjorn@kernel.org \
    --cc=borkmann@iogearbox.net \
    --cc=bpf@vger.kernel.org \
    --cc=dave@dtucker.co.uk \
    --cc=larysa.zaremba@intel.com \
    --cc=lorenzo@kernel.org \
    --cc=magnus.karlsson@intel.com \
    --cc=memxor@gmail.com \
    --cc=mtahhan@redhat.com \
    --cc=netdev@vger.kernel.org \
    --cc=xdp-hints@xdp-project.net \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox