Simply drop paged-pages in guest_remove_page(), and notify xenpaging to
drop reference to the gfn.
This version does not work for some reasons.
The guest hangs after pages got dropped.
Signed-off-by: Olaf Hering <olaf@xxxxxxxxx>
---
tools/xenpaging/xenpaging.c | 10 ++++++++
xen/arch/x86/mm/p2m.c | 51 +++++++++++++++++++++++++++++++++--------
xen/common/memory.c | 8 ++++++
xen/include/asm-x86/p2m.h | 4 +++
xen/include/public/mem_event.h | 1
5 files changed, 65 insertions(+), 9 deletions(-)
--- xen-unstable.hg-4.1.22344.orig/tools/xenpaging/xenpaging.c
+++ xen-unstable.hg-4.1.22344/tools/xenpaging/xenpaging.c
@@ -586,6 +586,15 @@ int main(int argc, char *argv[])
goto out;
}
+ if ( req.flags & MEM_EVENT_FLAG_DROP_PAGE )
+ {
+ DPRINTF("Dropping page %"PRIx64" p2m %x\n", req.gfn,
req.p2mt);
+
+ /* Notify policy of page being dropped */
+ policy_notify_paged_in(paging->mem_event.domain_id,
req.gfn);
+ }
+ else
+ {
/* Populate the page */
rc = xenpaging_populate_page(xch, paging, &req.gfn, fd, i);
if ( rc != 0 )
@@ -606,6 +615,7 @@ int main(int argc, char *argv[])
ERROR("Error resuming page");
goto out;
}
+ }
/* Evict a new page to replace the one we just paged in */
evict_victim(xch, paging, domain_id, &victims[i], fd, i);
--- xen-unstable.hg-4.1.22344.orig/xen/arch/x86/mm/p2m.c
+++ xen-unstable.hg-4.1.22344/xen/arch/x86/mm/p2m.c
@@ -1984,11 +1984,11 @@ static void audit_p2m(struct p2m_domain
{
mpbad++;
P2M_PRINTK("map mismatch mfn %#lx -> gfn %#lx -> mfn %#lx"
- " (-> gfn %#lx)\n",
+ " (-> gfn %#lx) p2mt %x\n",
mfn, gfn, mfn_x(p2mfn),
(mfn_valid(p2mfn)
? get_gpfn_from_mfn(mfn_x(p2mfn))
- : -1u));
+ : -1u), type);
/* This m2p entry is stale: the domain has another frame in
* this physical slot. No great disaster, but for neatness,
* blow away the m2p entry. */
@@ -2001,12 +2001,12 @@ static void audit_p2m(struct p2m_domain
if ( lp2mfn != mfn_x(p2mfn) )
{
P2M_PRINTK("linear mismatch gfn %#lx -> mfn %#lx "
- "(!= mfn %#lx)\n", gfn, lp2mfn, mfn_x(p2mfn));
+ "(!= mfn %#lx) p2mt %x\n", gfn, lp2mfn,
mfn_x(p2mfn), type);
}
}
// P2M_PRINTK("OK: mfn=%#lx, gfn=%#lx, p2mfn=%#lx, lp2mfn=%#lx\n",
- // mfn, gfn, p2mfn, lp2mfn);
+ // mfn, gfn, mfn_x(p2mfn), lp2mfn);
}
spin_unlock(&d->page_alloc_lock);
@@ -2132,11 +2132,9 @@ static void audit_p2m(struct p2m_domain
!p2m_is_shared(type) )
{
pmbad++;
- printk("mismatch: gfn %#lx -> mfn %#lx"
- " -> gfn %#lx\n", gfn, mfn, m2pfn);
P2M_PRINTK("mismatch: gfn %#lx -> mfn %#lx"
- " -> gfn %#lx\n", gfn, mfn, m2pfn);
- BUG();
+ " -> gfn %#lx (p2mt %x)\n", gfn, mfn,
m2pfn, type);
+ // BUG();
}
}
unmap_domain_page(l1e);
@@ -2168,7 +2166,7 @@ static void audit_p2m(struct p2m_domain
//P2M_PRINTK("p2m audit complete\n");
//if ( orphans_i | orphans_d | mpbad | pmbad )
// P2M_PRINTK("p2m audit found %lu orphans (%lu inval %lu debug)\n",
- // orphans_i + orphans_d, orphans_i, orphans_d,
+ // orphans_i + orphans_d, orphans_i, orphans_d);
if ( mpbad | pmbad )
P2M_PRINTK("p2m audit found %lu odd p2m, %lu bad m2p entries\n",
pmbad, mpbad);
@@ -2195,6 +2193,8 @@ p2m_remove_page(struct p2m_domain *p2m,
P2M_DEBUG("removing gfn=%#lx mfn=%#lx\n", gfn, mfn);
+ if (mfn_valid(_mfn(mfn)))
+ {
for ( i = 0; i < (1UL << page_order); i++ )
{
mfn_return = p2m->get_entry(p2m, gfn + i, &t, p2m_query);
@@ -2203,6 +2203,9 @@ p2m_remove_page(struct p2m_domain *p2m,
ASSERT( !p2m_is_valid(t) || mfn + i == mfn_x(mfn_return) );
}
set_p2m_entry(p2m, gfn, _mfn(INVALID_MFN), page_order, p2m_invalid);
+ }
+ else
+ P2M_DEBUG("set_p2m_entry %x\n", set_p2m_entry(p2m, gfn, _mfn(INVALID_MFN),
page_order, p2m_invalid));
}
void
@@ -2751,6 +2754,36 @@ int p2m_mem_paging_evict(struct p2m_doma
return 0;
}
+void p2m_mem_paging_drop_page(struct p2m_domain *p2m, unsigned long gfn)
+{
+ struct vcpu *v = current;
+ mem_event_request_t req;
+ p2m_type_t p2mt;
+ struct domain *d = p2m->domain;
+
+ memset(&req, 0, sizeof(req));
+
+ /* Check that there's space on the ring for this request */
+ if ( mem_event_check_ring(d) )
+ return;
+
+ gfn_to_mfn(p2m, gfn, &p2mt);
+ /* Pause domain */
+ if ( 0 && v->domain->domain_id == d->domain_id )
+ {
+ vcpu_pause_nosync(v);
+ req.flags |= MEM_EVENT_FLAG_VCPU_PAUSED;
+ }
+
+ /* Send request to pager */
+ req.flags |= MEM_EVENT_FLAG_DROP_PAGE;
+ req.gfn = gfn;
+ req.p2mt = p2mt;
+ req.vcpu_id = v->vcpu_id;
+
+ mem_event_put_request(d, &req);
+}
+
void p2m_mem_paging_populate(struct p2m_domain *p2m, unsigned long gfn)
{
struct vcpu *v = current;
--- xen-unstable.hg-4.1.22344.orig/xen/common/memory.c
+++ xen-unstable.hg-4.1.22344/xen/common/memory.c
@@ -162,6 +162,14 @@ int guest_remove_page(struct domain *d,
#ifdef CONFIG_X86
mfn = mfn_x(gfn_to_mfn(p2m_get_hostp2m(d), gmfn, &p2mt));
+ if ( unlikely(p2m_is_paging(p2mt)) )
+ {
+ gdprintk(XENLOG_INFO, "Domain %u invalidate paged gfn %lx/%x\n",
+ d->domain_id, gmfn, p2mt);
+ guest_physmap_remove_page(d, gmfn, mfn, 0);
+ p2m_mem_paging_drop_page(p2m_get_hostp2m(d), gmfn);
+ return 1;
+ }
#else
mfn = gmfn_to_mfn(d, gmfn);
#endif
--- xen-unstable.hg-4.1.22344.orig/xen/include/asm-x86/p2m.h
+++ xen-unstable.hg-4.1.22344/xen/include/asm-x86/p2m.h
@@ -480,6 +480,8 @@ int set_shared_p2m_entry(struct p2m_doma
int p2m_mem_paging_nominate(struct p2m_domain *p2m, unsigned long gfn);
/* Evict a frame */
int p2m_mem_paging_evict(struct p2m_domain *p2m, unsigned long gfn);
+/* Tell xenpaging to drop a paged out frame */
+void p2m_mem_paging_drop_page(struct p2m_domain *p2m, unsigned long gfn);
/* Start populating a paged out frame */
void p2m_mem_paging_populate(struct p2m_domain *p2m, unsigned long gfn);
/* Prepare the p2m for paging a frame in */
@@ -487,6 +489,8 @@ int p2m_mem_paging_prep(struct p2m_domai
/* Resume normal operation (in case a domain was paused) */
void p2m_mem_paging_resume(struct p2m_domain *p2m);
#else
+static inline void p2m_mem_paging_drop_page(struct p2m_domain *p2m, unsigned
long gfn)
+{ }
static inline void p2m_mem_paging_populate(struct p2m_domain *p2m, unsigned
long gfn)
{ }
#endif
--- xen-unstable.hg-4.1.22344.orig/xen/include/public/mem_event.h
+++ xen-unstable.hg-4.1.22344/xen/include/public/mem_event.h
@@ -37,6 +37,7 @@
#define MEM_EVENT_FLAG_VCPU_PAUSED (1 << 0)
#define MEM_EVENT_FLAG_DOM_PAUSED (1 << 1)
#define MEM_EVENT_FLAG_OUT_OF_MEM (1 << 2)
+#define MEM_EVENT_FLAG_DROP_PAGE (1 << 3)
typedef struct mem_event_shared_page {
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
|
Home