xl: export 'outstanding_pages' value from xcinfo

This patch provides the value of the currently outstanding pages
claimed for a specific domain. This is a value that influences
the global outstanding claims value (See patch: "xl: 'xl info'
print outstanding claims if enabled") returned via
xc_domain_get_outstanding_pages hypercall. This domain value
decrements as the memory is populated for the guest and
eventually reaches zero.

With this patch it is possible to utilize this field.

Acked-by: Ian Campbell <ian.campbell@citrix.com>
[v2: s/unclaimed/outstanding/ per Tim's suggestion]
[v3: Don't use SXP printout file per Ian's suggestion]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>

tools/libxl/libxl.c

@@ -528,6 +528,7 @@ static void xcinfo2xlinfo(const xc_domaininfo_t *xcinfo,
     else
         xlinfo->shutdown_reason  = ~0;
 
+    xlinfo->outstanding_memkb = PAGE_TO_MEMKB(xcinfo->outstanding_pages);
     xlinfo->current_memkb = PAGE_TO_MEMKB(xcinfo->tot_pages);
     xlinfo->shared_memkb = PAGE_TO_MEMKB(xcinfo->shr_pages);
     xlinfo->paged_memkb = PAGE_TO_MEMKB(xcinfo->paged_pages);

tools/libxl/libxl_types.idl

@@ -196,6 +196,7 @@ libxl_dominfo = Struct("dominfo",[
     # Otherwise set to a value guaranteed not to clash with any valid
     # LIBXL_SHUTDOWN_REASON_* constant.
     ("shutdown_reason", libxl_shutdown_reason),
+    ("outstanding_memkb",  MemKB),
     ("current_memkb",   MemKB),
     ("shared_memkb", MemKB),
     ("paged_memkb", MemKB),