diff mbox

[2/6] rdma: introduce ram_handle_compressed()

Message ID 1372373098-5877-3-git-send-email-mrhines@linux.vnet.ibm.com
State New
Headers show

Commit Message

mrhines@linux.vnet.ibm.com June 27, 2013, 10:44 p.m. UTC 
From: "Michael R. Hines" <mrhines@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: Juan Quintela <quintela@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Chegu Vinod <chegu_vinod@hp.com>
Tested-by: Chegu Vinod <chegu_vinod@hp.com>
Tested-by: Michael R. Hines <mrhines@us.ibm.com>
Signed-off-by: Michael R. Hines <mrhines@us.ibm.com>
---
 arch_init.c                   |   29 +++++++++++++++++++----------
 include/migration/migration.h |    2 ++
 2 files changed, 21 insertions(+), 10 deletions(-)

Comments

Peter Maydell June 27, 2013, 10:56 p.m. UTC | #1 
On 27 June 2013 23:44,  <mrhines@linux.vnet.ibm.com> wrote:
>  arch_init.c                   |   29 +++++++++++++++++++----------
>  include/migration/migration.h |    2 ++

Implementation in arch_init.c but prototype in migration.h?
The function pretty clearly has nothing to do with initialization
anyway, which suggests it's just in the wrong place (along with
a pile of other migration related code there).

thanks
-- PMM
Paolo Bonzini June 28, 2013, 7:17 a.m. UTC | #2 
Il 28/06/2013 00:56, Peter Maydell ha scritto:
> On 27 June 2013 23:44,  <mrhines@linux.vnet.ibm.com> wrote:
>>  arch_init.c                   |   29 +++++++++++++++++++----------
>>  include/migration/migration.h |    2 ++
> 
> Implementation in arch_init.c but prototype in migration.h?
> The function pretty clearly has nothing to do with initialization
> anyway, which suggests it's just in the wrong place (along with
> a pile of other migration related code there).

Yes, this used to be in vl.c, and was moved here by Blue Swirl.  We can
create a new savevm-ram.c file, but it is not really the fault of this
patch.

Paolo
diff mbox

Patch

diff --git a/arch_init.c b/arch_init.c
index ea9ddad..82657e4 100644
--- a/arch_init.c
+++ b/arch_init.c
@@ -777,6 +777,24 @@  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)
+{
+    if (ch != 0 || !is_zero_page(host)) {
+        memset(host, ch, 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
+    }
+}
+
 static int ram_load(QEMUFile *f, void *opaque, int version_id)
 {
     ram_addr_t addr;
@@ -847,16 +865,7 @@  static int ram_load(QEMUFile *f, void *opaque, int version_id)
             }
 
             ch = qemu_get_byte(f);
-            if (ch != 0 || !is_zero_page(host)) {
-                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 f0640e0..9d3cc85 100644
--- a/include/migration/migration.h
+++ b/include/migration/migration.h
@@ -109,6 +109,8 @@  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
  *