similar to: [PATCH v2] virtio-balloon: do not call blocking ops when !TASK_RUNNING

virtio balloon has this code: wait_event_interruptible(vb->config_change, (diff = towards_target(vb)) != 0 || vb->need_stats_update || kthread_should_stop() || freezing(current)); Which is a problem because towards_target() call might block after

virtio balloon has this code: wait_event_interruptible(vb->config_change, (diff = towards_target(vb)) != 0 || vb->need_stats_update || kthread_should_stop() || freezing(current)); Which is a problem because towards_target() call might block after

On Thu, Feb 26, 2015 at 06:08:49PM +0100, Peter Zijlstra wrote: > On Thu, Feb 26, 2015 at 09:30:31AM +0100, Michael S. Tsirkin wrote: > > On Thu, Feb 26, 2015 at 11:50:42AM +1030, Rusty Russell wrote: > > > Thomas Huth <thuth at linux.vnet.ibm.com> writes: > > > > Hi all, > > > > > > > > with the recent kernel 3.19, I get a kernel

On Thu, Feb 26, 2015 at 06:08:49PM +0100, Peter Zijlstra wrote: > On Thu, Feb 26, 2015 at 09:30:31AM +0100, Michael S. Tsirkin wrote: > > On Thu, Feb 26, 2015 at 11:50:42AM +1030, Rusty Russell wrote: > > > Thomas Huth <thuth at linux.vnet.ibm.com> writes: > > > > Hi all, > > > > > > > > with the recent kernel 3.19, I get a kernel

On Wed, 25 Feb 2015 16:11:27 +0100 Cornelia Huck <cornelia.huck at de.ibm.com> wrote: > On Wed, 25 Feb 2015 15:36:02 +0100 > "Michael S. Tsirkin" <mst at redhat.com> wrote: > > > virtio balloon has this code: > > wait_event_interruptible(vb->config_change, > > (diff = towards_target(vb)) != 0 > >

On Wed, 25 Feb 2015 16:11:27 +0100 Cornelia Huck <cornelia.huck at de.ibm.com> wrote: > On Wed, 25 Feb 2015 15:36:02 +0100 > "Michael S. Tsirkin" <mst at redhat.com> wrote: > > > virtio balloon has this code: > > wait_event_interruptible(vb->config_change, > > (diff = towards_target(vb)) != 0 > >

On Wed, 25 Feb 2015 15:14:36 +0100 "Michael S. Tsirkin" <mst at redhat.com> wrote: > virtio balloon has this code: > wait_event_interruptible(vb->config_change, > (diff = towards_target(vb)) != 0 > || vb->need_stats_update > || kthread_should_stop() >

On Wed, 25 Feb 2015 15:14:36 +0100 "Michael S. Tsirkin" <mst at redhat.com> wrote: > virtio balloon has this code: > wait_event_interruptible(vb->config_change, > (diff = towards_target(vb)) != 0 > || vb->need_stats_update > || kthread_should_stop() >

On Thu, Feb 26, 2015 at 11:50:42AM +1030, Rusty Russell wrote: > Thomas Huth <thuth at linux.vnet.ibm.com> writes: > > Hi all, > > > > with the recent kernel 3.19, I get a kernel warning when I start my > > KVM guest on s390 with virtio balloon enabled: > > The deeper problem is that virtio_ccw_get_config just silently fails on > OOM. > > Neither

On Thu, Feb 26, 2015 at 11:50:42AM +1030, Rusty Russell wrote: > Thomas Huth <thuth at linux.vnet.ibm.com> writes: > > Hi all, > > > > with the recent kernel 3.19, I get a kernel warning when I start my > > KVM guest on s390 with virtio balloon enabled: > > The deeper problem is that virtio_ccw_get_config just silently fails on > OOM. > > Neither

On Wed, 25 Feb 2015 15:36:02 +0100 "Michael S. Tsirkin" <mst at redhat.com> wrote: > virtio balloon has this code: > wait_event_interruptible(vb->config_change, > (diff = towards_target(vb)) != 0 > || vb->need_stats_update > || kthread_should_stop() >

On Wed, 25 Feb 2015 15:36:02 +0100 "Michael S. Tsirkin" <mst at redhat.com> wrote: > virtio balloon has this code: > wait_event_interruptible(vb->config_change, > (diff = towards_target(vb)) != 0 > || vb->need_stats_update > || kthread_should_stop() >

Hi all, with the recent kernel 3.19, I get a kernel warning when I start my KVM guest on s390 with virtio balloon enabled: [ 0.839687] do not call blocking ops when !TASK_RUNNING; state=1 set at [<0000000000174a1e>] prepare_to_wait_event+0x7e/0x108 [ 0.839694] ------------[ cut here ]------------ [ 0.839697] WARNING: at kernel/sched/core.c:7326 [ 0.839698]

Hi all, with the recent kernel 3.19, I get a kernel warning when I start my KVM guest on s390 with virtio balloon enabled: [ 0.839687] do not call blocking ops when !TASK_RUNNING; state=1 set at [<0000000000174a1e>] prepare_to_wait_event+0x7e/0x108 [ 0.839694] ------------[ cut here ]------------ [ 0.839697] WARNING: at kernel/sched/core.c:7326 [ 0.839698]

Thomas Huth <thuth at linux.vnet.ibm.com> writes: > Hi all, > > with the recent kernel 3.19, I get a kernel warning when I start my > KVM guest on s390 with virtio balloon enabled: The deeper problem is that virtio_ccw_get_config just silently fails on OOM. Neither get_config nor set_config are expected to fail. Cornelia, I think ccw and config_area should be allocated inside

Thomas Huth <thuth at linux.vnet.ibm.com> writes: > Hi all, > > with the recent kernel 3.19, I get a kernel warning when I start my > KVM guest on s390 with virtio balloon enabled: The deeper problem is that virtio_ccw_get_config just silently fails on OOM. Neither get_config nor set_config are expected to fail. Cornelia, I think ccw and config_area should be allocated inside

Workqueues have clean and rich API for all basic operations. The code is usually easier and better readable. It can be easily tuned for the given purpose. In many cases, it allows to avoid an extra kernel thread. It helps to stop the growing number of them. Also there will be less thread-specific hacks all over the kernel code. It forces making the task selfcontained. There is no longer an

Workqueues have clean and rich API for all basic operations. The code is usually easier and better readable. It can be easily tuned for the given purpose. In many cases, it allows to avoid an extra kernel thread. It helps to stop the growing number of them. Also there will be less thread-specific hacks all over the kernel code. It forces making the task selfcontained. There is no longer an

From: Petr Mladek <pmladek at suse.cz> This patch moves the deferred work from the "vballoon" kthread into a system freezable workqueue. We do not need to maintain and run a dedicated kthread. Also the event driven workqueues API makes the logic much easier. Especially, we do not longer need an own wait queue, wait function, and freeze point. The conversion is pretty

On Fri, Dec 04, 2015 at 02:37:51PM +0100, Petr Mladek wrote: > From: Petr Mladek <pmladek at suse.cz> > > This patch moves the deferred work from the "vballoon" kthread into a > system freezable workqueue. > > We do not need to maintain and run a dedicated kthread. Also the event > driven workqueues API makes the logic much easier. Especially, we do > not