From nobody Tue Dec 2 02:05:19 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 952A92F12CD; Thu, 20 Nov 2025 21:25:05 +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=1763673905; cv=none; b=S8lKJZU3HwYIy8gZcMAsDaBd6pO7iXrS2xgLkvAR6LbfHRjtEzXWHlJV9KuB4ycArh8OQRtjJKDzA11nrW7SrvJULcjlhzyAk0C39HrVwpYr18d88wAl5ZgkkK206hXyZyx2+1hZw6J9NkYHdX5M6yc3ZmPkUiW63lF30kDJeb8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763673905; c=relaxed/simple; bh=Xs4AEFpvDY6JzCUFXkOpJeETRBiY34vm/qu0XZbAVcM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=sFOeCcV11DI/nm9inkO9vJmcqKKStra/mW0zy7A5/dAhPiPDQhe2lgPKIcvr7IingrpyQL6RXjgAlGhPSpDYK1lsJbarVfhMI3igJAYRty7LRu8q465JXhdHUm/Fqz7U9fxEVWirOPX5ZH4yceGI/DQqlj8FiebaPxjHPReAf5E= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=tGU9vA0u; 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="tGU9vA0u" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 10B4DC4CEF1; Thu, 20 Nov 2025 21:25:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1763673905; bh=Xs4AEFpvDY6JzCUFXkOpJeETRBiY34vm/qu0XZbAVcM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tGU9vA0ucsFWp6B9XXnY7o7XV791mPu6UI5szkwx4hc5qI4Ar7mkhIRSUqfHcfWLw WnyL2dfOIy7ul01z8SglOlCdK0BGZRvpqJoU54BdFa0Q2PIPhuM1JR7EsvAI92A5av FxJkl5TpFwECRDlW1t8ARXeNNkjehxMCh2PeMj7P/dDSIKoztchSBJse5w2EN/ZLym j68/uoJcKgzVGhGO25iu2VlMeCZ7GpgNSCojS7IJO1eIhLIKtauyBFVJ4+g3qhh2D2 D36tKfXrrYv/bPlcVgn3C47WYTGeX0GrI5ngPKba7e5YnfftsvAMWNhbs93w8F452J neOuUbAWEmc5g== 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: [PATCHv3 bpf-next 5/8] ftrace: Add update_ftrace_direct_mod function Date: Thu, 20 Nov 2025 22:23:59 +0100 Message-ID: <20251120212402.466524-6-jolsa@kernel.org> X-Mailer: git-send-email 2.51.1 In-Reply-To: <20251120212402.466524-1-jolsa@kernel.org> References: <20251120212402.466524-1-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 | 68 ++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 74 insertions(+) diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index c571deeff840..4e2c0ed769fc 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -552,6 +552,7 @@ 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 @@ -589,6 +590,11 @@ 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 cc730a8fd087..5243aefb6096 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -6486,6 +6486,74 @@ 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_hash *orig_hash =3D ops->func_hash->filter_hash; + struct ftrace_func_entry *entry, *tmp; + static struct ftrace_ops tmp_ops =3D { + .func =3D ftrace_stub, + .flags =3D FTRACE_OPS_FL_STUB, + }; + unsigned long size, i; + int err; + + 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); + + /* 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 2.51.1