From nobody Wed Dec 17 16:10:14 2025 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2CD1A2DE1E0; Mon, 15 Dec 2025 21:15:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765833319; cv=none; b=T/T6N5dxoIB0bP9oE/odYSc1u0ScKN5tSxK+36cNW8IMoC9chbDPPrkc3UaT4Q1Lnp35Rf1FE1tc7cVJRnrsig7IuVKQu3bq3LBwIi3kR54WpEqurccyMaxzXr36Uu6rVIt5gJxgFjZBePDvHeHbnP5TUyf2W53R0N58/mHwO4M= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765833319; c=relaxed/simple; bh=p6gqLffg23UILKDsdjUK8VuxMZVSEGZ26VdVvM6E4Fc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Bj5z+FAY7LT1aI7keFzCi2IuvZ2m2EQXtkI/7Hyc1bdbWZkcivapQQKCTADIo2TfE3DbJqe6NHXVxICjpsVwZg7bRAvpqiusuXI37TJx5Ttwv10V2E1mMUdlTxzSHMFcegCYbMxGF5rgLr6i8/4jf5tIkjxUW0nEHGr4wYW7jrU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Af6OpNzq; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Af6OpNzq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 84B31C16AAE; Mon, 15 Dec 2025 21:15:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1765833318; bh=p6gqLffg23UILKDsdjUK8VuxMZVSEGZ26VdVvM6E4Fc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Af6OpNzq71MMfPjqgppB3DbyU1JFHnVbLu7u99k3Fr1SdUKtHcDJGXmpxRn40xMiQ pjuHBGySCVEXLLBXBL4iFFCHeryRxDJmIhfF+5w6edhWhhiWZZnPr4zIz//MCBAyVN j3DMzV3tdMqUij5mAbwo5nDW6G6KmYkCgaftGzyM8noRwKpcgZGK0D95geAg6pqCBa DnwxfsQTy8vctJwstW3F3wTXq22AdwtiCC04luxMnsSgoE9P/viKWRxys/Y6AiClOw 9q/rLqt1SGc0hLYDx0oVdOWPx+mklPwZCYfwZzpVLcOQL5Ld8vVtA5KS1rVVEQvCd3 65RC8yoyu5s+g== From: Jiri Olsa To: Steven Rostedt , Florent Revest , Mark Rutland Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Menglong Dong , Song Liu Subject: [PATCHv5 bpf-next 6/9] ftrace: Add update_ftrace_direct_mod function Date: Mon, 15 Dec 2025 22:13:59 +0100 Message-ID: <20251215211402.353056-7-jolsa@kernel.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251215211402.353056-1-jolsa@kernel.org> References: <20251215211402.353056-1-jolsa@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Adding update_ftrace_direct_mod function that modifies all entries (ip -> direct) provided in hash argument to direct ftrace ops and updates its attachments. The difference to current modify_ftrace_direct is: - hash argument that allows to modify multiple ip -> direct entries at once This change will allow us to have simple ftrace_ops for all bpf direct interface users in following changes. Signed-off-by: Jiri Olsa --- include/linux/ftrace.h | 6 ++++ kernel/trace/ftrace.c | 72 ++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 78 insertions(+) diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index ac4b473c7fd3..c3bf9cede1fe 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -545,6 +545,7 @@ int modify_ftrace_direct_nolock(struct ftrace_ops *ops,= unsigned long addr); =20 int update_ftrace_direct_add(struct ftrace_ops *ops, struct ftrace_hash *h= ash); int update_ftrace_direct_del(struct ftrace_ops *ops, struct ftrace_hash *h= ash); +int update_ftrace_direct_mod(struct ftrace_ops *ops, struct ftrace_hash *h= ash, bool do_direct_lock); =20 void ftrace_stub_direct_tramp(void); =20 @@ -582,6 +583,11 @@ static inline int update_ftrace_direct_del(struct ftra= ce_ops *ops, struct ftrace return -ENODEV; } =20 +static inline int update_ftrace_direct_mod(struct ftrace_ops *ops, struct = ftrace_hash *hash, bool do_direct_lock) +{ + return -ENODEV; +} + /* * This must be implemented by the architecture. * It is the way the ftrace direct_ops helper, when called diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 48dc0de5f2ce..95a38fb18ed7 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -6489,6 +6489,78 @@ int update_ftrace_direct_del(struct ftrace_ops *ops,= struct ftrace_hash *hash) return err; } =20 +int update_ftrace_direct_mod(struct ftrace_ops *ops, struct ftrace_hash *h= ash, bool do_direct_lock) +{ + struct ftrace_func_entry *entry, *tmp; + static struct ftrace_ops tmp_ops =3D { + .func =3D ftrace_stub, + .flags =3D FTRACE_OPS_FL_STUB, + }; + struct ftrace_hash *orig_hash; + unsigned long size, i; + int err =3D -EINVAL; + + if (!hash_count(hash)) + return -EINVAL; + if (check_direct_multi(ops)) + return -EINVAL; + if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) + return -EINVAL; + if (direct_functions =3D=3D EMPTY_HASH) + return -EINVAL; + + if (do_direct_lock) + mutex_lock(&direct_mutex); + + orig_hash =3D ops->func_hash ? ops->func_hash->filter_hash : NULL; + if (!orig_hash) + goto unlock; + + /* Enable the tmp_ops to have the same functions as the direct ops */ + ftrace_ops_init(&tmp_ops); + tmp_ops.func_hash =3D ops->func_hash; + + err =3D register_ftrace_function_nolock(&tmp_ops); + if (err) + goto unlock; + + /* + * Call __ftrace_hash_update_ipmodify() here, so that we can call + * ops->ops_func for the ops. This is needed because the above + * register_ftrace_function_nolock() worked on tmp_ops. + */ + err =3D __ftrace_hash_update_ipmodify(ops, orig_hash, orig_hash, true); + if (err) + goto out; + + /* + * Now the ftrace_ops_list_func() is called to do the direct callers. + * We can safely change the direct functions attached to each entry. + */ + mutex_lock(&ftrace_lock); + + size =3D 1 << hash->size_bits; + for (i =3D 0; i < size; i++) { + hlist_for_each_entry(entry, &hash->buckets[i], hlist) { + tmp =3D __ftrace_lookup_ip(direct_functions, entry->ip); + if (!tmp) + continue; + tmp->direct =3D entry->direct; + } + } + + mutex_unlock(&ftrace_lock); + +out: + /* Removing the tmp_ops will add the updated direct callers to the functi= ons */ + unregister_ftrace_function(&tmp_ops); + +unlock: + if (do_direct_lock) + mutex_unlock(&direct_mutex); + return err; +} + #endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */ =20 /** --=20 2.52.0