Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754211AbcDDMcd (ORCPT ); Mon, 4 Apr 2016 08:32:33 -0400 Received: from www.linutronix.de ([62.245.132.108]:33533 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751968AbcDDMcc (ORCPT ); Mon, 4 Apr 2016 08:32:32 -0400 From: Anna-Maria Gleixner To: linux-kernel@vger.kernel.org Cc: rt@linutronix.de, Anna-Maria Gleixner , David Vrabel , Stefano Stabellini , xen-devel@lists.xenproject.org Subject: [PATCH] xen: Add comment for missing FROZEN notifier transitions Date: Mon, 4 Apr 2016 14:32:20 +0200 Message-Id: <1459773140-43707-1-git-send-email-anna-maria@linutronix.de> X-Mailer: git-send-email 2.7.0 X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001,URIBL_BLOCKED=0.001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1823 Lines: 61 Xen guests do not offline/online CPUs during suspend/resume and therefore FROZEN notifier transitions are not required. Add this explanation as a comment in the code to get not confused why CPU_TASKS_FROZEN masked transitions are not considered. Cc: David Vrabel Cc: Stefano Stabellini Cc: xen-devel@lists.xenproject.org Signed-off-by: Anna-Maria Gleixner --- arch/arm/xen/enlighten.c | 6 ++++++ arch/x86/xen/enlighten.c | 7 +++++++ drivers/xen/events/events_fifo.c | 6 ++++++ 3 files changed, 19 insertions(+) --- a/arch/arm/xen/enlighten.c +++ b/arch/arm/xen/enlighten.c @@ -213,6 +213,12 @@ static int xen_cpu_notification(struct n unsigned long action, void *hcpu) { + /* + * Xen guests do not offline/online CPUs during + * suspend/resume, thus CPU_TASKS_FROZEN masked transitions + * are not considered. + */ + switch (action) { case CPU_STARTING: xen_percpu_init(); --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -1788,6 +1788,13 @@ static int xen_hvm_cpu_notify(struct not void *hcpu) { int cpu = (long)hcpu; + + /* + * Xen guests do not offline/online CPUs during + * suspend/resume, thus CPU_TASKS_FROZEN masked transitions + * are not considered. + */ + switch (action) { case CPU_UP_PREPARE: xen_vcpu_setup(cpu); --- a/drivers/xen/events/events_fifo.c +++ b/drivers/xen/events/events_fifo.c @@ -425,6 +425,12 @@ static int evtchn_fifo_cpu_notification( int cpu = (long)hcpu; int ret = 0; + /* + * Xen guests do not offline/online CPUs during + * suspend/resume, thus CPU_TASKS_FROZEN masked transitions + * are not considered. + */ + switch (action) { case CPU_UP_PREPARE: if (!per_cpu(cpu_control_block, cpu))