Re: [RFD] workqueue: WQ_MEM_RECLAIM usage in network drivers

2016-03-24 Thread Johannes Berg
On Sun, 2016-03-20 at 14:55 -0400, Tejun Heo wrote: > If everything else is working, I'd be happy to throw in > WQ_MEM_RECLAIM but I really don't want to add it if it doesn't > actually achieve the goal.  Can a wireless person chime in here? > I think for many wireless devices the workqueue,

Re: [RFD] workqueue: WQ_MEM_RECLAIM usage in network drivers

2016-03-24 Thread Johannes Berg
On Sun, 2016-03-20 at 14:55 -0400, Tejun Heo wrote: > If everything else is working, I'd be happy to throw in > WQ_MEM_RECLAIM but I really don't want to add it if it doesn't > actually achieve the goal.  Can a wireless person chime in here? > I think for many wireless devices the workqueue,

Re: [RFD] workqueue: WQ_MEM_RECLAIM usage in network drivers

2016-03-20 Thread Tejun Heo
Hello, On Fri, Mar 18, 2016 at 05:24:05PM -0400, J. Bruce Fields wrote: > > But does that actually work? It's pointless to add WQ_MEM_RECLAIM to > > workqueues unless all other things are also guaranteed to make forward > > progress regardless of memory pressure. > > It's supposed to work. > >

Re: [RFD] workqueue: WQ_MEM_RECLAIM usage in network drivers

2016-03-20 Thread Tejun Heo
Hello, On Fri, Mar 18, 2016 at 05:24:05PM -0400, J. Bruce Fields wrote: > > But does that actually work? It's pointless to add WQ_MEM_RECLAIM to > > workqueues unless all other things are also guaranteed to make forward > > progress regardless of memory pressure. > > It's supposed to work. > >

Re: [RFD] workqueue: WQ_MEM_RECLAIM usage in network drivers

2016-03-19 Thread Tejun Heo
Hello, Jeff. On Thu, Mar 17, 2016 at 09:32:16PM -0400, Jeff Layton wrote: > > * Are network devices expected to be able to serve as a part of > > storage stack which is depended upon for memory reclamation? > > I think they should be. Cached NFS pages can consume a lot of memory, > and

Re: [RFD] workqueue: WQ_MEM_RECLAIM usage in network drivers

2016-03-19 Thread Tejun Heo
Hello, Jeff. On Thu, Mar 17, 2016 at 09:32:16PM -0400, Jeff Layton wrote: > > * Are network devices expected to be able to serve as a part of > > storage stack which is depended upon for memory reclamation? > > I think they should be. Cached NFS pages can consume a lot of memory, > and

[RFD] workqueue: WQ_MEM_RECLAIM usage in network drivers

2016-03-19 Thread Tejun Heo
Hello, Years ago, workqueue got reimplemented to use common worker pools across different workqueues and a new set of more expressive workqueue creation APIs, alloc_*workqueue() were introduced. The old create_*workqueue() became simple wrappers around alloc_*workqueue() with the most

[RFD] workqueue: WQ_MEM_RECLAIM usage in network drivers

2016-03-19 Thread Tejun Heo
Hello, Years ago, workqueue got reimplemented to use common worker pools across different workqueues and a new set of more expressive workqueue creation APIs, alloc_*workqueue() were introduced. The old create_*workqueue() became simple wrappers around alloc_*workqueue() with the most

Re: [RFD] workqueue: WQ_MEM_RECLAIM usage in network drivers

2016-03-19 Thread Jeff Layton
On Thu, 17 Mar 2016 09:45:46 -0700 Tejun Heo wrote: > Hello, > > Years ago, workqueue got reimplemented to use common worker pools > across different workqueues and a new set of more expressive workqueue > creation APIs, alloc_*workqueue() were introduced. The old >

Re: [RFD] workqueue: WQ_MEM_RECLAIM usage in network drivers

2016-03-19 Thread Jeff Layton
On Thu, 17 Mar 2016 09:45:46 -0700 Tejun Heo wrote: > Hello, > > Years ago, workqueue got reimplemented to use common worker pools > across different workqueues and a new set of more expressive workqueue > creation APIs, alloc_*workqueue() were introduced. The old > create_*workqueue() became

Re: [RFD] workqueue: WQ_MEM_RECLAIM usage in network drivers

2016-03-19 Thread J. Bruce Fields
On Fri, Mar 18, 2016 at 04:46:23PM -0400, Tejun Heo wrote: > Hello, Jeff. > > On Thu, Mar 17, 2016 at 09:32:16PM -0400, Jeff Layton wrote: > > > * Are network devices expected to be able to serve as a part of > > > storage stack which is depended upon for memory reclamation? > > > > I think

Re: [RFD] workqueue: WQ_MEM_RECLAIM usage in network drivers

2016-03-19 Thread J. Bruce Fields
On Fri, Mar 18, 2016 at 04:46:23PM -0400, Tejun Heo wrote: > Hello, Jeff. > > On Thu, Mar 17, 2016 at 09:32:16PM -0400, Jeff Layton wrote: > > > * Are network devices expected to be able to serve as a part of > > > storage stack which is depended upon for memory reclamation? > > > > I think