From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (bilbo.ozlabs.org [103.22.144.67]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3zVGN95tJLzDqlb for ; Mon, 29 Jan 2018 15:13:45 +1100 (AEDT) In-Reply-To: <2142489eb41f758b5d04919a8efbb16794f16b0f.1490135047.git.julia@ni.com> To: Julia Cartwright , Anatolij Gustschin , Benjamin Herrenschmidt , Paul Mackerras From: Michael Ellerman Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org Subject: Re: [v2,3/9] powerpc: mpc52xx_gpt: make use of raw_spinlock variants Message-Id: <3zVGN94KNbz9sP9@ozlabs.org> Date: Mon, 29 Jan 2018 15:13:45 +1100 (AEDT) List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, 2017-03-21 at 22:43:03 UTC, Julia Cartwright wrote: > The mpc52xx_gpt code currently implements an irq_chip for handling > interrupts; due to how irq_chip handling is done, it's necessary for the > irq_chip methods to be invoked from hardirq context, even on a a > real-time kernel. Because the spinlock_t type becomes a "sleeping" > spinlock w/ RT kernels, it is not suitable to be used with irq_chips. > > A quick audit of the operations under the lock reveal that they do only > minimal, bounded work, and are therefore safe to do under a raw spinlock. > > Signed-off-by: Julia Cartwright Applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/77720c82915a8b7797e0041af95707 cheers