From: Keir Fraser <keir.fraser@eu.citrix.com>
To: Jan Beulich <JBeulich@novell.com>,
"xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>
Subject: Re: [PATCH] don't save Xen heap pages during domain save
Date: Tue, 15 Jun 2010 13:22:59 +0100 [thread overview]
Message-ID: <C83D2F33.17896%keir.fraser@eu.citrix.com> (raw)
In-Reply-To: <4C1783FB0200007800006777@vpn.id2.novell.com>
I've applied all your patches as of xen-unstable:21621. Are they all
suitable for Xen 4.0.x do you think? What about 3.4.x?
Thanks,
Keir
On 15/06/2010 12:45, "Jan Beulich" <JBeulich@novell.com> wrote:
> As discussed in the thread starting at
> http://lists.xensource.com/archives/html/xen-devel/2010-05/msg01383.html,
> don't save Xen heap pages in order to avoid overallocation when the
> domain gets restored, as those pages would get (temporarily) backed
> with normal RAM pages by the restore code.
>
> This requires making DOMCTL_getpageframeinfo{2,3} usable for HVM guests,
> meaning that the input to these must be treated as GMFNs.
>
> Signed-off-by: Jan Beulich <jbeulich@novell.com>
>
> --- 2010-06-15.orig/tools/libxc/xc_domain_save.c 2010-06-01 13:39:57.000000000
> +0200
> +++ 2010-06-15/tools/libxc/xc_domain_save.c 2010-06-15 09:32:42.000000000
> +0200
> @@ -1288,58 +1288,64 @@ int xc_domain_save(xc_interface *xch, in
> goto out;
> }
>
> - if ( hvm )
> + /* Get page types */
> + if ( xc_get_pfn_type_batch(xch, dom, batch, pfn_type) )
> {
> - /* Look for and skip completely empty batches. */
> - for ( j = 0; j < batch; j++ )
> - {
> - if ( !pfn_err[j] )
> - break;
> - pfn_type[j] |= XEN_DOMCTL_PFINFO_XTAB;
> - }
> - if ( j == batch )
> - {
> - munmap(region_base, batch*PAGE_SIZE);
> - continue; /* bail on this batch: no valid pages */
> - }
> - for ( ; j < batch; j++ )
> - if ( pfn_err[j] )
> - pfn_type[j] |= XEN_DOMCTL_PFINFO_XTAB;
> + PERROR("get_pfn_type_batch failed");
> + goto out;
> }
> - else
> +
> + for ( run = j = 0; j < batch; j++ )
> {
> - /* Get page types */
> - if ( xc_get_pfn_type_batch(xch, dom, batch, pfn_type) )
> - {
> - PERROR("get_pfn_type_batch failed");
> - goto out;
> - }
> + unsigned long gmfn = pfn_batch[j];
>
> - for ( j = 0; j < batch; j++ )
> + if ( !hvm )
> + gmfn = pfn_to_mfn(gmfn);
> +
> + if ( pfn_err[j] )
> {
> - unsigned long mfn = pfn_to_mfn(pfn_batch[j]);
> -
> if ( pfn_type[j] == XEN_DOMCTL_PFINFO_XTAB )
> - {
> - DPRINTF("type fail: page %i mfn %08lx\n",
> - j, mfn);
> continue;
> - }
> -
> - if ( debug )
> + DPRINTF("map fail: page %i mfn %08lx err %d\n",
> + j, gmfn, pfn_err[j]);
> + pfn_type[j] = XEN_DOMCTL_PFINFO_XTAB;
> + continue;
> + }
> +
> + if ( pfn_type[j] == XEN_DOMCTL_PFINFO_XTAB )
> + {
> + DPRINTF("type fail: page %i mfn %08lx\n", j, gmfn);
> + continue;
> + }
> +
> + /* canonicalise mfn->pfn */
> + pfn_type[j] |= pfn_batch[j];
> + ++run;
> +
> + if ( debug )
> + {
> + if ( hvm )
> + DPRINTF("%d pfn=%08lx sum=%08lx\n",
> + iter,
> + pfn_type[j],
> + csum_page(region_base + (PAGE_SIZE*j)));
> + else
> DPRINTF("%d pfn= %08lx mfn= %08lx [mfn]= %08lx"
> " sum= %08lx\n",
> iter,
> - pfn_type[j] | pfn_batch[j],
> - mfn,
> - mfn_to_pfn(mfn),
> + pfn_type[j],
> + gmfn,
> + mfn_to_pfn(gmfn),
> csum_page(region_base + (PAGE_SIZE*j)));
> -
> - /* canonicalise mfn->pfn */
> - pfn_type[j] |= pfn_batch[j];
> }
> }
>
> + if ( !run )
> + {
> + munmap(region_base, batch*PAGE_SIZE);
> + continue; /* bail on this batch: no valid pages */
> + }
> +
> if ( wrexact(io_fd, &batch, sizeof(unsigned int)) )
> {
> PERROR("Error when writing to state file (2)");
> --- 2010-06-15.orig/xen/arch/x86/domctl.c 2010-03-02 09:11:28.000000000 +0100
> +++ 2010-06-15/xen/arch/x86/domctl.c 2010-06-15 09:32:42.000000000 +0200
> @@ -207,11 +207,12 @@ long arch_do_domctl(
>
> for ( j = 0; j < k; j++ )
> {
> - unsigned long type = 0, mfn = arr[j];
> + unsigned long type = 0, mfn = gmfn_to_mfn(d, arr[j]);
>
> page = mfn_to_page(mfn);
>
> - if ( unlikely(!mfn_valid(mfn)) )
> + if ( unlikely(!mfn_valid(mfn)) ||
> + unlikely(is_xen_heap_mfn(mfn)) )
> type = XEN_DOMCTL_PFINFO_XTAB;
> else if ( xsm_getpageframeinfo(page) != 0 )
> ;
> @@ -306,14 +307,15 @@ long arch_do_domctl(
> for ( j = 0; j < k; j++ )
> {
> struct page_info *page;
> - unsigned long mfn = arr32[j];
> + unsigned long mfn = gmfn_to_mfn(d, arr32[j]);
>
> page = mfn_to_page(mfn);
>
> if ( domctl->cmd == XEN_DOMCTL_getpageframeinfo3)
> arr32[j] = 0;
>
> - if ( unlikely(!mfn_valid(mfn)) )
> + if ( unlikely(!mfn_valid(mfn)) ||
> + unlikely(is_xen_heap_mfn(mfn)) )
> arr32[j] |= XEN_DOMCTL_PFINFO_XTAB;
> else if ( xsm_getpageframeinfo(page) != 0 )
> continue;
>
>
next prev parent reply other threads:[~2010-06-15 12:22 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-06-15 11:45 [PATCH] don't save Xen heap pages during domain save Jan Beulich
2010-06-15 12:22 ` Keir Fraser [this message]
2010-06-15 12:39 ` Jan Beulich
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