diff mbox series

[bpf-next,v2,1/2] bpf: Show target_{obj,btf}_id in tracing link fdinfo

Message ID 20230517103126.68372-2-laoar.shao@gmail.com (mailing list archive)
State Accepted
Commit e859e429511afb21d3f784bd0ccdf500d40b73ef
Delegated to: BPF
Headers show
Series bpf: Show target_{obj,btf}_id for tracing link | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for bpf-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 10 this patch: 10
netdev/cc_maintainers success CCed 12 of 12 maintainers
netdev/build_clang success Errors and warnings before: 8 this patch: 8
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 10 this patch: 10
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 19 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
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bpf/vmtest-bpf-next-PR success PR summary
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Commit Message

Yafang Shao May 17, 2023, 10:31 a.m. UTC 
The target_btf_id can help us understand which kernel function is
linked by a tracing prog. The target_btf_id and target_obj_id have
already been exposed to userspace, so we just need to show them.

The result as follows,

$ cat /proc/10673/fdinfo/10
pos:    0
flags:  02000000
mnt_id: 15
ino:    2094
link_type:      tracing
link_id:        2
prog_tag:       a04f5eef06a7f555
prog_id:        13
attach_type:    24
target_obj_id:  1
target_btf_id:  13964

Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Song Liu <song@kernel.org>
---
 kernel/bpf/syscall.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 909c112..b262108 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -2968,10 +2968,17 @@  static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link,
 {
 	struct bpf_tracing_link *tr_link =
 		container_of(link, struct bpf_tracing_link, link.link);
+	u32 target_btf_id, target_obj_id;
 
+	bpf_trampoline_unpack_key(tr_link->trampoline->key,
+				  &target_obj_id, &target_btf_id);
 	seq_printf(seq,
-		   "attach_type:\t%d\n",
-		   tr_link->attach_type);
+		   "attach_type:\t%d\n"
+		   "target_obj_id:\t%u\n"
+		   "target_btf_id:\t%u\n",
+		   tr_link->attach_type,
+		   target_obj_id,
+		   target_btf_id);
 }
 
 static int bpf_tracing_link_fill_link_info(const struct bpf_link *link,