From mboxrd@z Thu Jan 1 00:00:00 1970 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 A0C852C21FF; Wed, 3 Dec 2025 08:25:15 +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=1764750315; cv=none; b=PE3ud2FSc+sU5K1us3HtInTRo8DdS/Busr4XfAqrVEmamSB2I1cP/wsuvT/yLzWUWVSEPS1LG8q0CFFtxdrbLBLPnV0VDJp4S2Zeo2DrLA8lSqIkG4T0HtBUy6oIAt0al0l2Ihg8JudmAvynoIpmckvg8M7P31F8p3CxK06GrTg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764750315; c=relaxed/simple; bh=pLgdjqwxCmhdWC6Ct/H1SR3MVjIRGtL9kTHwK/vSQVg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=mLGia+tHnAUsXPhFMPjf7gvJdSQN2XfVk90imN77FHirJAJv1q2GrHmPSc/H6cMwQoVEZkREoskjPG/7lAiK3kgfyWS7YqJoT1keMsmJapLRLj2mcERSZWaGyoBeiJe72Ka/GlN6khGzv5jCvdB+1hVZ/Bk8t7G+S3FfsIiOyb0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Zn8G+9ZK; 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="Zn8G+9ZK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6150DC4CEFB; Wed, 3 Dec 2025 08:25:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1764750315; bh=pLgdjqwxCmhdWC6Ct/H1SR3MVjIRGtL9kTHwK/vSQVg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Zn8G+9ZKr+LfhPle/3GxYOBDUz5mKUF0Mk1s4FShEHpgZeVYHOL6VOMlWE22IG9G/ B/g7mAdFI2/PcqVDaurUoITlvirqRV7SiEoP1SR+d6MkLOegg97QTxRcjpP2cE2xKy 2ZUpSYz5ipWao2WmDEj54jLdc29c+5DGLib6QARHRvaRCIQKiVEyYBcSOsyWbRl8Fr MT/Mxa2X61YnLEk0mxRsa0cYLfSiR0VX5faFFUGlWukljC7DRZvtlK0tG/5iFhwOCw oGcSeLbidHqlFTcOXNiuXIqhpmuOez/zsQF5FjdF+slLyq7HdoX330uERIfaUywGU4 7t3UOHMKvV/Fw== 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: [PATCHv4 bpf-next 6/9] ftrace: Add update_ftrace_direct_mod function Date: Wed, 3 Dec 2025 09:23:59 +0100 Message-ID: <20251203082402.78816-7-jolsa@kernel.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251203082402.78816-1-jolsa@kernel.org> References: <20251203082402.78816-1-jolsa@kernel.org> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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 bac9dd784826..c27b7381c5f1 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); 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); @@ -589,6 +590,11 @@ 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 01e830be20e3..c77f620b3eb3 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -6490,6 +6490,78 @@ int update_ftrace_direct_del(struct ftrace_ops *ops, struct ftrace_hash *hash) return err; } +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; + + 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