Messages in this thread | | | Subject | Re: [Xen-devel] [PATCH] xen: Add comment for missing FROZEN notifier transitions | From | Julien Grall <> | Date | Mon, 4 Apr 2016 17:21:45 +0100 |
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(CC Stefano new e-mail address)
Hello Anna-Maria,
On 04/04/2016 13:32, Anna-Maria Gleixner wrote: > 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 <david.vrabel@citrix.com> > Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> > Cc: xen-devel@lists.xenproject.org > Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> > --- > 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. > + */
NIT: The '*' is not aligned with the others.
> + > switch (action) { > case CPU_UP_PREPARE: > if (!per_cpu(cpu_control_block, cpu)) >
Regards,
-- Julien Grall
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