Re: [PATCH v17 4/6] virtio-balloon: VIRTIO_BALLOON_F_SG

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 11/04/2017 07:28 PM, Tetsuo Handa wrote:
Wei Wang wrote:
On 11/03/2017 07:25 PM, Tetsuo Handa wrote:

If this is inside vb->balloon_lock mutex (isn't this?), xb_set_page() must not
use __GFP_DIRECT_RECLAIM allocation, for leak_balloon_sg_oom() will be blocked
on vb->balloon_lock mutex.
OK. Since the preload() doesn't need too much memory (< 4K in total),
how about GFP_NOWAIT here?
Maybe GFP_NOWAIT | __GFP_NOWARN ?

Sounds good to me. I also plan to move "xb_set_page()" under mutex_lock, that is,

    fill_balloon()
    {
        ...
        mutex_lock(&vb->balloon_lock);

        vb->num_pfns = 0;
        while ((page = balloon_page_pop(&pages))) {
==>        xb_set_page(..,page,..);
                balloon_page_enqueue(&vb->vb_dev_info, page);
        ...
    }

As explained in the xbitmap patch, we need the lock to avoid concurrent access to the bitmap.

Best,
Wei
_______________________________________________
Virtualization mailing list
Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx
https://lists.linuxfoundation.org/mailman/listinfo/virtualization



[Index of Archives]     [KVM Development]     [Libvirt Development]     [Libvirt Users]     [CentOS Virtualization]     [Netdev]     [Ethernet Bridging]     [Linux Wireless]     [Kernel Newbies]     [Security]     [Linux for Hams]     [Netfilter]     [Bugtraq]     [Yosemite Forum]     [MIPS Linux]     [ARM Linux]     [Linux RAID]     [Linux Admin]     [Samba]

  Powered by Linux