[PATCH bpf-next v2 00/21] bpf: Add tracing_multi link support for bpf progs · Leon Hwang <hidden> · 2026-10-12
[PATCH bpf-next v2 01/21] bpf: Initialize ftrace_managed in bpf_trampoline_get() · Leon Hwang <hidden> · 2026-10-12
Re: [PATCH bpf-next v2 01/21] bpf: Initialize ftrace_managed in bpf_trampoline_get() · Jiri Olsa <hidden> · 2026-10-14
[PATCH bpf-next v2 02/21] bpf: Drop unnecessary ftrace_location() in register/unregister/modify_fentry_multi() · Leon Hwang <hidden> · 2026-10-12
Re: [PATCH bpf-next v2 02/21] bpf: Drop unnecessary ftrace_location() in register/unregister/modify_fentry_multi() · Jiri Olsa <hidden> · 2026-10-14
[PATCH bpf-next v2 03/21] bpf, x86: Factor out bpf_arch_text_poke_prepare_insns() helper on x86_64 · Leon Hwang <hidden> · 2026-10-12
[PATCH bpf-next v2 04/21] bpf, x86: Factor out bpf_arch_text_poke_check_ip() helper on x86_64 · Leon Hwang <hidden> · 2026-10-12
[PATCH bpf-next v2 05/21] bpf, x86: Introduce bpf_arch_text_poke_batch() on x86_64 · Leon Hwang <hidden> · 2026-10-12
[PATCH bpf-next v2 06/21] bpf: Add bpf_text_poke_batch() helper in trampoline · Leon Hwang <hidden> · 2026-10-12
Re: [PATCH bpf-next v2 06/21] bpf: Add bpf_text_poke_batch() helper in trampoline · bot+bpf-ci@kernel.org · 2026-10-12
[PATCH bpf-next v2 07/21] bpf: Check tgt_prog before is_tracing_multi_id() in verifier · Leon Hwang <hidden> · 2026-10-12
[PATCH bpf-next v2 08/21] bpf: Move helpers out of CONFIG_HAVE_SINGLE_FTRACE_DIRECT_OPS guard in trampoline · Leon Hwang <hidden> · 2026-10-12
Re: [PATCH bpf-next v2 08/21] bpf: Move helpers out of CONFIG_HAVE_SINGLE_FTRACE_DIRECT_OPS guard in trampoline · bot+bpf-ci@kernel.org · 2026-10-12
[PATCH bpf-next v2 09/21] bpf: Add bpf_trampoline_multi_prog_attach/detach() · Leon Hwang <hidden> · 2026-10-12
Re: [PATCH bpf-next v2 09/21] bpf: Add bpf_trampoline_multi_prog_attach/detach() · sashiko-bot@kernel.org · 2026-10-12
Re: [PATCH bpf-next v2 09/21] bpf: Add bpf_trampoline_multi_prog_attach/detach() · bot+bpf-ci@kernel.org · 2026-10-12
Re: [PATCH bpf-next v2 09/21] bpf: Add bpf_trampoline_multi_prog_attach/detach() · Jiri Olsa <hidden> · 2026-10-14
[PATCH bpf-next v2 10/21] bpf: Shrink CONFIG_HAVE_SINGLE_FTRACE_DIRECT_OPS guard scope for bpf_tracing_multi_attach() · Leon Hwang <hidden> · 2026-10-12
[PATCH bpf-next v2 11/21] bpf: Add tracing_multi link support for bpf progs · Leon Hwang <hidden> · 2026-10-12
Re: [PATCH bpf-next v2 11/21] bpf: Add tracing_multi link support for bpf progs · bot+bpf-ci@kernel.org · 2026-10-12
Re: [PATCH bpf-next v2 11/21] bpf: Add tracing_multi link support for bpf progs · Jiri Olsa <hidden> · 2026-10-14
[PATCH bpf-next v2 12/21] libbpf: Add tracing_multi link support for bpf progs · Leon Hwang <hidden> · 2026-10-12
[PATCH bpf-next v2 13/21] bpf: Add tracing_multi link fdinfo support for bpf progs · Leon Hwang <hidden> · 2026-10-12
[PATCH bpf-next v2 14/21] bpf: Add tracing_multi link info support for bpf progs · Leon Hwang <hidden> · 2026-10-12
Re: [PATCH bpf-next v2 14/21] bpf: Add tracing_multi link info support for bpf progs · bot+bpf-ci@kernel.org · 2026-10-12
Re: [PATCH bpf-next v2 14/21] bpf: Add tracing_multi link info support for bpf progs · sashiko-bot@kernel.org · 2026-10-12
Re: [PATCH bpf-next v2 14/21] bpf: Add tracing_multi link info support for bpf progs · Jiri Olsa <hidden> · 2026-10-14
Re: [PATCH bpf-next v2 14/21] bpf: Add tracing_multi link info support for bpf progs · kernel test robot <hidden> · 2026-10-15
[PATCH bpf-next v2 15/21] selftests/bpf: Add tracing_multi bpf prog attach test · Leon Hwang <hidden> · 2026-10-12
[PATCH bpf-next v2 16/21] selftests/bpf: Add tracing_multi bpf prog attach failure tests · Leon Hwang <hidden> · 2026-10-12
[PATCH bpf-next v2 17/21] selftests/bpf: Add tracing_multi bpf prog cookie test · Leon Hwang <hidden> · 2026-10-12
[PATCH bpf-next v2 18/21] selftests/bpf: Add tracing_multi bpf prog rollback test · Leon Hwang <hidden> · 2026-10-12
Re: [PATCH bpf-next v2 18/21] selftests/bpf: Add tracing_multi bpf prog rollback test · sashiko-bot@kernel.org · 2026-10-12
Re: [PATCH bpf-next v2 18/21] selftests/bpf: Add tracing_multi bpf prog rollback test · Jiri Olsa <hidden> · 2026-10-14
[PATCH bpf-next v2 19/21] selftests/bpf: Add tracing_multi bpf prog link info test · Leon Hwang <hidden> · 2026-10-12
Re: [PATCH bpf-next v2 19/21] selftests/bpf: Add tracing_multi bpf prog link info test · bot+bpf-ci@kernel.org · 2026-10-12
Re: [PATCH bpf-next v2 19/21] selftests/bpf: Add tracing_multi bpf prog link info test · sashiko-bot@kernel.org · 2026-10-12
[PATCH bpf-next v2 20/21] selftests/bpf: Test tailcall with fentry.multi · Leon Hwang <hidden> · 2026-10-12
[PATCH bpf-next v2 21/21] selftests/bpf: Benchmark tracing_multi bpf progs attachment · Leon Hwang <hidden> · 2026-10-12
Re: [PATCH bpf-next v2 21/21] selftests/bpf: Benchmark tracing_multi bpf progs attachment · bot+bpf-ci@kernel.org · 2026-10-12
Re: [PATCH bpf-next v2 21/21] selftests/bpf: Benchmark tracing_multi bpf progs attachment · sashiko-bot@kernel.org · 2026-10-12
Re: [PATCH bpf-next v2 00/21] bpf: Add tracing_multi link support for bpf progs · Jiri Olsa <hidden> · 2026-10-14
Re: [PATCH bpf-next v2 00/21] bpf: Add tracing_multi link support for bpf progs · Leon Hwang <hidden> · 2026-10-15
Re: [PATCH bpf-next v2 00/21] bpf: Add tracing_multi link support for bpf progs · Alexei Starovoitov <hidden> · 2026-10-15

[PATCH bpf-next v2 02/21] bpf: Drop unnecessary ftrace_location() in register/unregister/modify_fentry_multi()

COOLING5d

From: Leon Hwang <hidden>
Date: 2026-10-12 15:41:33
Also in: bpf, linux-kselftest, lkml
Subsystem: bpf [core], bpf [general] (safe dynamic programs and tools), the rest · Maintainers: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Linus Torvalds

Revision v2 of 2 in this series.

Revisions (2)

2026-08-09 v1 [diff vs current]
2026-10-12 v2 current

Since 'tr->ip' is already a 'ftrace_location()'-ed IP in
bpf_trampoline_lookup(), it is unnecessary to call ftrace_location() again
in register/unregister/modify_fentry_multi().

No functional changes intended.

Signed-off-by: Leon Hwang <redacted>
---
 kernel/bpf/trampoline.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
index 17f2a8133f61..21d460866dfe 100644
--- a/kernel/bpf/trampoline.c
+++ b/kernel/bpf/trampoline.c

@@ -1629,8 +1629,8 @@ static void ftrace_hash_add(struct ftrace_hash *hash, struct ftrace_func_entry *
 static int register_fentry_multi(struct bpf_trampoline *tr, struct bpf_tramp_image *im, void *ptr)
 {
 	unsigned long addr = (unsigned long) im->image;
-	unsigned long ip = ftrace_location(tr->ip);
 	struct bpf_tracing_multi_data *data = ptr;
+	unsigned long ip = tr->ip;
 
 	/*
 	 * Different BTF ids get different trampolines, but they can still

@@ -1651,13 +1651,12 @@ static int register_fentry_multi(struct bpf_trampoline *tr, struct bpf_tramp_ima
 static int unregister_fentry_multi(struct bpf_trampoline *tr, u32 orig_flags, void *ptr)
 {
 	unsigned long addr = (unsigned long) tr->cur_image->image;
-	unsigned long ip = ftrace_location(tr->ip);
 	struct bpf_tracing_multi_data *data = ptr;
 
 	if (bpf_trampoline_use_jmp(tr->flags))
 		addr = ftrace_jmp_set(addr);
 
-	ftrace_hash_add(data->unreg, data->entry, ip, addr);
+	ftrace_hash_add(data->unreg, data->entry, tr->ip, addr);
 	tr->cur_image = NULL;
 	return 0;
 }

@@ -1666,13 +1665,12 @@ static int modify_fentry_multi(struct bpf_trampoline *tr, u32 orig_flags, struct
 			       bool lock_direct_mutex, void *ptr)
 {
 	unsigned long addr = (unsigned long) im->image;
-	unsigned long ip = ftrace_location(tr->ip);
 	struct bpf_tracing_multi_data *data = ptr;
 
 	if (bpf_trampoline_use_jmp(tr->flags))
 		addr = ftrace_jmp_set(addr);
 
-	ftrace_hash_add(data->modify, data->entry, ip, addr);
+	ftrace_hash_add(data->modify, data->entry, tr->ip, addr);
 	tr->cur_image = im;
 	return 0;
 }

-- 
2.55.0

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