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authorDr. David Alan Gilbert <dgilbert@redhat.com>2017-02-24 18:28:37 +0000
committerDr. David Alan Gilbert <dgilbert@redhat.com>2017-02-28 11:30:23 +0000
commit28abd2001445d4e702b1dc9147d0015b189cd37a (patch)
tree254587e36a3666b1517d65de0fad61cda0df3099 /migration
parent41d84210d403a686052fb5fc4c9f027e13e92185 (diff)
postcopy: Load huge pages in one go
The existing postcopy RAM load loop already ensures that it glues together whole host-pages from the target page size chunks sent over the wire. Modify the definition of host page that it uses to be the RAM block page size and thus be huge pages where appropriate. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Laurent Vivier <lvivier@redhat.com> Message-Id: <20170224182844.32452-10-dgilbert@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Diffstat (limited to 'migration')
-rw-r--r--migration/ram.c13
1 files changed, 8 insertions, 5 deletions
diff --git a/migration/ram.c b/migration/ram.c
index ff866643b6..9f28da2eab 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -2390,7 +2390,7 @@ static int ram_load_postcopy(QEMUFile *f)
{
int flags = 0, ret = 0;
bool place_needed = false;
- bool matching_page_sizes = qemu_host_page_size == TARGET_PAGE_SIZE;
+ bool matching_page_sizes = false;
MigrationIncomingState *mis = migration_incoming_get_current();
/* Temporary page that is later 'placed' */
void *postcopy_host_page = postcopy_get_tmp_page(mis);
@@ -2420,8 +2420,11 @@ static int ram_load_postcopy(QEMUFile *f)
ret = -EINVAL;
break;
}
+ matching_page_sizes = block->page_size == TARGET_PAGE_SIZE;
/*
- * Postcopy requires that we place whole host pages atomically.
+ * Postcopy requires that we place whole host pages atomically;
+ * these may be huge pages for RAMBlocks that are backed by
+ * hugetlbfs.
* To make it atomic, the data is read into a temporary page
* that's moved into place later.
* The migration protocol uses, possibly smaller, target-pages
@@ -2429,9 +2432,9 @@ static int ram_load_postcopy(QEMUFile *f)
* of a host page in order.
*/
page_buffer = postcopy_host_page +
- ((uintptr_t)host & ~qemu_host_page_mask);
+ ((uintptr_t)host & (block->page_size - 1));
/* If all TP are zero then we can optimise the place */
- if (!((uintptr_t)host & ~qemu_host_page_mask)) {
+ if (!((uintptr_t)host & (block->page_size - 1))) {
all_zero = true;
} else {
/* not the 1st TP within the HP */
@@ -2449,7 +2452,7 @@ static int ram_load_postcopy(QEMUFile *f)
* page
*/
place_needed = (((uintptr_t)host + TARGET_PAGE_SIZE) &
- ~qemu_host_page_mask) == 0;
+ (block->page_size - 1)) == 0;
place_source = postcopy_host_page;
}
last_host = host;