From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9A096EE0209 for ; Tue, 30 Dec 2025 14:51:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Eoaapz9EtK3TAhRmsenoXM7ALjqOcunzvkSGndUIVq8=; b=KV+0fcpJbLZT3muZdWgDbcGs1W mKaex7NYITyupkvCbM0FFiEBY1C5dXiQtn04AiwJDJyv1MyTHUSD6Ma2325YJb0F/YMkzJwHJK5qj pUB42a2vDf0KQgTHEANrrENi4LHv6/IdeVRDtUVFSLAA+P7ALVhzns6CooILQq4GJ6j7QxoNitw5J uZqlPOV2t+v9m4J6TNX1M5EoO71WeNBVf4fJuwbt9iuThEHmBfrfqbRCfRkCxjMRjFMz13xyG8CVB S8tK2vehQD9uimDBgG4lGEVHunu+V+QFyixcqhD1PSoRZjUZ3RxxNeR87ZEofczV1SeecBQsfJ4AF cFYFxPxg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vab4K-00000004xQf-0SOs; Tue, 30 Dec 2025 14:51:30 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vab4F-00000004xOU-3I1R for linux-arm-kernel@lists.infradead.org; Tue, 30 Dec 2025 14:51:24 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 124F540C36; Tue, 30 Dec 2025 14:51:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E0177C4CEFB; Tue, 30 Dec 2025 14:51:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1767106282; bh=rQ2iTT+yI1RxB3ZOf5yqVU+kkCf2GWoXN4fuBj4HQFM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fUXc+yTIU2u3TkJ9XVhrI2uuB61jgcjXj9LT+fxq6j8kT3aank129i3vbPoPDsGh8 iA+eOIcmv/NEB08NF1hoIaB6WqJJ6Vpv/m0Fjy9fwuS4tINMiaxzSwmIUXdjKKvkqh 4SOEqRfvQs3aVq0YHp+ymoyR0T4JdJ8oNgA4NgegoMTHSuhnpWwybfKvRxmH+hmViw 0QtJ7mdqFGPp9baHWyprwzi+5I0E6HIqsB5R6ZtHgCDwL72GBIsC8PDpE/gUGOh2zy ZFUodG0rRVZGRVilXIpPTRzIFuBGU3U73P8knefkOMGE3L4IiQgkfk4u+qeJEXDqa9 AShJM3+0Xillw== 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: [PATCHv6 bpf-next 6/9] ftrace: Add update_ftrace_direct_mod function Date: Tue, 30 Dec 2025 15:50:07 +0100 Message-ID: <20251230145010.103439-7-jolsa@kernel.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251230145010.103439-1-jolsa@kernel.org> References: <20251230145010.103439-1-jolsa@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251230_065123_866103_09BF0160 X-CRM114-Status: GOOD ( 19.63 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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 | 94 ++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 100 insertions(+) diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index a3cc1b48c9fc..6c1680ab8bf9 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); int update_ftrace_direct_add(struct ftrace_ops *ops, struct ftrace_hash *hash); int update_ftrace_direct_del(struct ftrace_ops *ops, struct ftrace_hash *hash); +int update_ftrace_direct_mod(struct ftrace_ops *ops, struct ftrace_hash *hash, bool do_direct_lock); void ftrace_stub_direct_tramp(void); @@ -582,6 +583,11 @@ static inline int update_ftrace_direct_del(struct ftrace_ops *ops, struct ftrace return -ENODEV; } +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 8b75166fb223..d24f28677007 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -6542,6 +6542,100 @@ int update_ftrace_direct_del(struct ftrace_ops *ops, struct ftrace_hash *hash) return err; } +/** + * update_ftrace_direct_mod - Updates @ops by modifing its direct + * callers provided in @hash + * @ops: The address of the struct ftrace_ops object + * @hash: The address of the struct ftrace_hash object + * @do_direct_lock: If true lock the direct_mutex + * + * This is used to modify custom direct callers (ip -> addr) in + * @ops specified via @hash. + * + * This can be called from within ftrace ops_func callback with + * direct_mutex already locked, in which case @do_direct_lock + * needs to be false. + * + * Returns: zero on success. Non zero on error, which includes: + * -EINVAL - The @hash is empty + * -EINVAL - The @ops is not registered + */ +int update_ftrace_direct_mod(struct ftrace_ops *ops, struct ftrace_hash *hash, bool do_direct_lock) +{ + struct ftrace_func_entry *entry, *tmp; + static struct ftrace_ops tmp_ops = { + .func = ftrace_stub, + .flags = FTRACE_OPS_FL_STUB, + }; + struct ftrace_hash *orig_hash; + unsigned long size, i; + int err = -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 == EMPTY_HASH) + return -EINVAL; + + /* + * We can be called from within ops_func callback with direct_mutex + * already taken. + */ + if (do_direct_lock) + mutex_lock(&direct_mutex); + + orig_hash = 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 = ops->func_hash; + + err = 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 = __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 = 1 << hash->size_bits; + for (i = 0; i < size; i++) { + hlist_for_each_entry(entry, &hash->buckets[i], hlist) { + tmp = __ftrace_lookup_ip(direct_functions, entry->ip); + if (!tmp) + continue; + tmp->direct = entry->direct; + } + } + + mutex_unlock(&ftrace_lock); + +out: + /* Removing the tmp_ops will add the updated direct callers to the functions */ + unregister_ftrace_function(&tmp_ops); + +unlock: + if (do_direct_lock) + mutex_unlock(&direct_mutex); + return err; +} + #endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */ /** -- 2.52.0