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 4C1732C21C5; Thu, 7 May 2026 17:09:53 +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=1778173793; cv=none; b=iyd4Nr7DixaZpeFHFZ4rF0jbDBZH4uupcrXiPR4qY90Ke/k7gwFu/Kmqtp8RzdlHNmuWoaINf2ZMgLmjOf5gtpHainGSvgRBsF1z4DiV/+5wXg3eOw1sqKgoJIl9gW0/jW0JgKrJap6QUBOJ4w1OCJYDtKH3rsILI0XEwNe4dho= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778173793; c=relaxed/simple; bh=BnQHU3UiLfVgh8EzJY+SASyVRoECPKgyAiZaumt6cvM=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Mj+3al/wu/1Eho1x0OKXmnigw4Ef3tLay8rlSQ6E+SG3WsZWaclqJAiOMYsYhpCu2cC4CyuVhvcYB5PaxQreLsEAf7ckPhLuy9XcekOfKsfhBJqNDSUm3/ggxGP4IIrqpxEbVgiQRslJ1EjFJdy7OXqRyg48HbcEDeXWX9cGFQE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=K+fMIoTK; 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="K+fMIoTK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 128E8C2BCC9; Thu, 7 May 2026 17:09:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1778173793; bh=BnQHU3UiLfVgh8EzJY+SASyVRoECPKgyAiZaumt6cvM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=K+fMIoTK8+cYw/K12C5AbW97Q21lKJRyLSjMaJY6M1ZF90EvTag7vtXilc0Y13812 WV6AzedmGlrUGkll8Tl5tpfJXFPEog+kdbU7iQ97UvghgWNgwepI6upwPES+UEpHJ/ 07zrt0voUQBWWfCIhE8Zhzx1usxLpYJQdJ5b5GeCDMEcVwP4a+ilM79UMAcsaEpSD2 yZwSCPiYMLsJCQe/HUPKI6aXeX0HOX1Ly+0VaZFexwhVbbwNjqeYor1PXyiCH3vX6Q EMccY3AslVgPq1VMRh1MpWCP4Sy7S3p+1fYCnWq3fqJLAMP9/Rev2Mm4xKwsRHeHq6 n6dwUXQPpYDIQ== Received: by paulmck-ThinkPad-P17-Gen-1.home (Postfix, from userid 1000) id AB2A8CE0C96; Thu, 7 May 2026 10:09:52 -0700 (PDT) From: "Paul E. McKenney" To: rcu@vger.kernel.org Cc: linux-kernel@vger.kernel.org, kernel-team@meta.com, rostedt@goodmis.org, "Paul E. McKenney" , Puranjay Mohan , Andy Whitcroft , Joe Perches , Dwaipayan Ray , Lukas Bulwahn Subject: [PATCH 3/7] checkpatch: Undeprecate rcu_read_lock_trace() and rcu_read_unlock_trace() Date: Thu, 7 May 2026 10:09:46 -0700 Message-Id: <20260507170950.2040199-3-paulmck@kernel.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit It turns out that there are BPF use cases that rely on nesting RCU Tasks Trace readers. These use cases are well-served by the old rcu_read_lock_trace() and rcu_read_unlock_trace() functions that maintain a nesting counter in the task_struct structure. But these use cases incur a performance penalty when using the shiny new rcu_read_lock_tasks_trace() and rcu_read_unlock_tasks_trace() functions, which nest in the same way that SRCU does. This means that rcu_read_lock_trace() and rcu_read_unlock_trace() will be with us for some time. Therefore, remove the checkpatch.pl deprecation. Reported-by: Puranjay Mohan Signed-off-by: Paul E. McKenney Cc: Andy Whitcroft Cc: Joe Perches Cc: Dwaipayan Ray Cc: Lukas Bulwahn --- scripts/checkpatch.pl | 2 -- 1 file changed, 2 deletions(-) diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 0492d6afc9a1fc..7a0aa139a2424a 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -865,8 +865,6 @@ our %deprecated_apis = ( "DEFINE_IDR" => "DEFINE_XARRAY", "idr_init" => "xa_init", "idr_init_base" => "xa_init_flags", - "rcu_read_lock_trace" => "rcu_read_lock_tasks_trace", - "rcu_read_unlock_trace" => "rcu_read_unlock_tasks_trace", ); #Create a search pattern for all these strings to speed up a loop below -- 2.40.1