From: "Michael R. Hines" <mrhi...@us.ibm.com>
This gives RDMA shared access to madvise() on the destination side
when an entire chunk is found to be zero.
Reviewed-by: Paolo Bonzini <pbonz...@redhat.com>
Signed-off-by: Michael R. Hines <mrhi...@us.ibm.com>
---
arch_init.c | 24 ++++++++++++++++--------
include/migration/migration.h | 2 ++
2 files changed, 18 insertions(+), 8 deletions(-)
diff --git a/arch_init.c b/arch_init.c
index 819ca5a..2f1fdd3 100644
--- a/arch_init.c
+++ b/arch_init.c
@@ -782,6 +782,21 @@ static inline void *host_from_stream_offset(QEMUFile *f,
return NULL;
}
+/*
+ * If a page (or a whole RDMA chunk) has been
+ * determined to be zero, then zap it.
+ */
+void ram_handle_compressed(void *host, uint8_t ch, uint64_t size)
+{
+ memset(host, ch, TARGET_PAGE_SIZE);
+#ifndef _WIN32
+ if (ch == 0 && (!kvm_enabled() || kvm_has_sync_mmu()) &&
+ getpagesize() <= TARGET_PAGE_SIZE) {
+ qemu_madvise(host, size, QEMU_MADV_DONTNEED);
+ }
+#endif
+}
+
static int ram_load(QEMUFile *f, void *opaque, int version_id)
{
ram_addr_t addr;
@@ -849,14 +864,7 @@ static int ram_load(QEMUFile *f, void *opaque, int
version_id)
}
ch = qemu_get_byte(f);
- memset(host, ch, TARGET_PAGE_SIZE);
-#ifndef _WIN32
- if (ch == 0 &&
- (!kvm_enabled() || kvm_has_sync_mmu()) &&
- getpagesize() <= TARGET_PAGE_SIZE) {
- qemu_madvise(host, TARGET_PAGE_SIZE, QEMU_MADV_DONTNEED);
- }
-#endif
+ ram_handle_compressed(host, ch, TARGET_PAGE_SIZE);
} else if (flags & RAM_SAVE_FLAG_PAGE) {
void *host;
diff --git a/include/migration/migration.h b/include/migration/migration.h
index 1eeaa40..110f4ad 100644
--- a/include/migration/migration.h
+++ b/include/migration/migration.h
@@ -108,6 +108,8 @@ uint64_t xbzrle_mig_pages_transferred(void);
uint64_t xbzrle_mig_pages_overflow(void);
uint64_t xbzrle_mig_pages_cache_miss(void);
+void ram_handle_compressed(void *host, uint8_t ch, uint64_t size);
+
/**
* @migrate_add_blocker - prevent migration from proceeding
*
--
1.7.10.4
