Message ID | 20110215093527.GB8341@tiehlicka.suse.cz |
---|---|
State | Awaiting Upstream, archived |
Delegated to: | David Miller |
Headers | show |
On Tue, 15 Feb 2011 08:05:27 pm Michal Hocko wrote: > Hi, > we have started seeing a lot of allocator messages complaining about > failed allocations from virtnet_poll in soft IRQ. Could you consider the > following patch, please? Do we really want to silence this? Isn't warning about it kind of the point? Your network is probably sucking if this happens... Cheers, Rusty. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue 15-02-11 20:41:29, Rusty Russell wrote: > On Tue, 15 Feb 2011 08:05:27 pm Michal Hocko wrote: > > Hi, > > we have started seeing a lot of allocator messages complaining about > > failed allocations from virtnet_poll in soft IRQ. Could you consider the > > following patch, please? > > Do we really want to silence this? Isn't warning about it kind of the > point? Your network is probably sucking if this happens... What can user do about it? Is the low level memory allocator message very much usefull for him? Maybe we can add a printk_once in the fail path with some more useful and virtio specific message. Thanks
On Tue, 15 Feb 2011 08:55:50 pm Michal Hocko wrote: > On Tue 15-02-11 20:41:29, Rusty Russell wrote: > > On Tue, 15 Feb 2011 08:05:27 pm Michal Hocko wrote: > > > Hi, > > > we have started seeing a lot of allocator messages complaining about > > > failed allocations from virtnet_poll in soft IRQ. Could you consider the > > > following patch, please? > > > > Do we really want to silence this? Isn't warning about it kind of the > > point? Your network is probably sucking if this happens... > > What can user do about it? Is the low level memory allocator message > very much usefull for him? Maybe we can add a printk_once in the fail > path with some more useful and virtio specific message. That's an argument against ever printing any message. What we need to know is why does this happen with virtio_net and not other cards? If it happens to them too, and they silently fall back, all good. I want to make sure we're not papering over a real problem... Thanks, Rusty. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue 15-02-11 10:35:27, Michal Hocko wrote: [...] > [22798.508903] The following is only an harmless informational message. > [22798.508909] Unless you get a _continuous_flood_ of these messages it means > [22798.508911] everything is working fine. Allocations from irqs cannot be > [22798.508913] perfectly reliable and the kernel is designed to handle that. I have just realized that the above text is SLES specific so only the line below with stack trace and memory info is printed. Sorry for confusion > [22798.508917] loop3: page allocation failure. order:0, mode:0x20, alloc_flags:0x30 pflags:0x80208040
On Tue 15-02-11 21:39:03, Rusty Russell wrote: > On Tue, 15 Feb 2011 08:55:50 pm Michal Hocko wrote: > > On Tue 15-02-11 20:41:29, Rusty Russell wrote: > > > On Tue, 15 Feb 2011 08:05:27 pm Michal Hocko wrote: > > > > Hi, > > > > we have started seeing a lot of allocator messages complaining about > > > > failed allocations from virtnet_poll in soft IRQ. Could you consider the > > > > following patch, please? > > > > > > Do we really want to silence this? Isn't warning about it kind of the > > > point? Your network is probably sucking if this happens... > > > > What can user do about it? Is the low level memory allocator message > > very much usefull for him? Maybe we can add a printk_once in the fail > > path with some more useful and virtio specific message. > > That's an argument against ever printing any message. Well, honestly, I do not see much point for this message but it is there for ages so it maybe it is valueable for somebody... > > What we need to know is why does this happen with virtio_net and not other > cards? The machine just happened to be short on memory due to a strong memory pressure. > If it happens to them too, and they silently fall back, all good. > > I want to make sure we're not papering over a real problem... > > Thanks, > Rusty.
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 90a23e4..aea1e51 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -477,7 +477,7 @@ again: } if (vi->num < vi->max / 2) { - if (!try_fill_recv(vi, GFP_ATOMIC)) + if (!try_fill_recv(vi, GFP_ATOMIC|__GFP_NOWARN)) schedule_delayed_work(&vi->refill, 0); }