[Qemu-devel] [PATCH v7 1/3] migration: postcopy_place_page factoring out

[Qemu-devel] [PATCH v7 1/3] migration: postcopy_place_page factoring out

[Alexey Perevalov]

Need to mark copied pages as closer as possible to the place where it
tracks down. That will be necessary in futher patch.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
---
 migration/postcopy-ram.c | 13 +++++++------
 migration/postcopy-ram.h |  4 ++--
 migration/ram.c          |  4 ++--
 3 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c
index 7e21e6f..996e64d 100644
--- a/migration/postcopy-ram.c
+++ b/migration/postcopy-ram.c
@@ -564,9 +564,10 @@ int postcopy_ram_enable_notify(MigrationIncomingState *mis)
  * returns 0 on success
  */
 int postcopy_place_page(MigrationIncomingState *mis, void *host, void *from,
-                        size_t pagesize)
+                        RAMBlock *rb)
 {
     struct uffdio_copy copy_struct;
+    size_t pagesize = qemu_ram_pagesize(rb);
 
     copy_struct.dst = (uint64_t)(uintptr_t)host;
     copy_struct.src = (uint64_t)(uintptr_t)from;
@@ -595,11 +596,11 @@ int postcopy_place_page(MigrationIncomingState *mis, void *host, void *from,
  * returns 0 on success
  */
 int postcopy_place_page_zero(MigrationIncomingState *mis, void *host,
-                             size_t pagesize)
+                             RAMBlock *rb)
 {
     trace_postcopy_place_page_zero(host);
 
-    if (pagesize == getpagesize()) {
+    if (qemu_ram_pagesize(rb) == getpagesize()) {
         struct uffdio_zeropage zero_struct;
         zero_struct.range.start = (uint64_t)(uintptr_t)host;
         zero_struct.range.len = getpagesize();
@@ -629,7 +630,7 @@ int postcopy_place_page_zero(MigrationIncomingState *mis, void *host,
             memset(mis->postcopy_tmp_zero_page, '\0', mis->largest_page_size);
         }
         return postcopy_place_page(mis, host, mis->postcopy_tmp_zero_page,
-                                   pagesize);
+                                   rb);
     }
 
     return 0;
@@ -692,14 +693,14 @@ int postcopy_ram_enable_notify(MigrationIncomingState *mis)
 }
 
 int postcopy_place_page(MigrationIncomingState *mis, void *host, void *from,
-                        size_t pagesize)
+                        RAMBlock *rb)
 {
     assert(0);
     return -1;
 }
 
 int postcopy_place_page_zero(MigrationIncomingState *mis, void *host,
-                        size_t pagesize)
+                        RAMBlock *rb)
 {
     assert(0);
     return -1;
diff --git a/migration/postcopy-ram.h b/migration/postcopy-ram.h
index 52d51e8..78a3591 100644
--- a/migration/postcopy-ram.h
+++ b/migration/postcopy-ram.h
@@ -72,14 +72,14 @@ void postcopy_discard_send_finish(MigrationState *ms,
  * returns 0 on success
  */
 int postcopy_place_page(MigrationIncomingState *mis, void *host, void *from,
-                        size_t pagesize);
+                        RAMBlock *rb);
 
 /*
  * Place a zero page at (host) atomically
  * returns 0 on success
  */
 int postcopy_place_page_zero(MigrationIncomingState *mis, void *host,
-                             size_t pagesize);
+                             RAMBlock *rb);
 
 /* The current postcopy state is read/set by postcopy_state_get/set
  * which update it atomically.
diff --git a/migration/ram.c b/migration/ram.c
index 1b08296..9cc1b17 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -2470,10 +2470,10 @@ static int ram_load_postcopy(QEMUFile *f)
 
             if (all_zero) {
                 ret = postcopy_place_page_zero(mis, place_dest,
-                                               block->page_size);
+                                               block);
             } else {
                 ret = postcopy_place_page(mis, place_dest,
-                                          place_source, block->page_size);
+                                          place_source, block);
             }
         }
         if (!ret) {
-- 
1.8.3.1

[Qemu-devel] [PATCH v7 2/3] migration: introduce qemu_ufd_copy_ioctl helper

[Alexey Perevalov]

Just for placing auxilary operations inside helper,
auxilary operations like: track received pages,
notify about copying operation in futher patches.

Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
---
 migration/postcopy-ram.c | 34 +++++++++++++++++++++-------------
 1 file changed, 21 insertions(+), 13 deletions(-)

diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c
index 996e64d..be497bb 100644
--- a/migration/postcopy-ram.c
+++ b/migration/postcopy-ram.c
@@ -559,6 +559,25 @@ int postcopy_ram_enable_notify(MigrationIncomingState *mis)
     return 0;
 }
 
+static int qemu_ufd_copy_ioctl(int userfault_fd, void *host_addr,
+        void *from_addr, uint64_t pagesize)
+{
+    if (from_addr) {
+        struct uffdio_copy copy_struct;
+        copy_struct.dst = (uint64_t)(uintptr_t)host_addr;
+        copy_struct.src = (uint64_t)(uintptr_t)from_addr;
+        copy_struct.len = pagesize;
+        copy_struct.mode = 0;
+        return ioctl(userfault_fd, UFFDIO_COPY, &copy_struct);
+    } else {
+        struct uffdio_zeropage zero_struct;
+        zero_struct.range.start = (uint64_t)(uintptr_t)host_addr;
+        zero_struct.range.len = pagesize;
+        zero_struct.mode = 0;
+        return ioctl(userfault_fd, UFFDIO_ZEROPAGE, &zero_struct);
+    }
+}
+
 /*
  * Place a host page (from) at (host) atomically
  * returns 0 on success
@@ -566,20 +585,14 @@ int postcopy_ram_enable_notify(MigrationIncomingState *mis)
 int postcopy_place_page(MigrationIncomingState *mis, void *host, void *from,
                         RAMBlock *rb)
 {
-    struct uffdio_copy copy_struct;
     size_t pagesize = qemu_ram_pagesize(rb);
 
-    copy_struct.dst = (uint64_t)(uintptr_t)host;
-    copy_struct.src = (uint64_t)(uintptr_t)from;
-    copy_struct.len = pagesize;
-    copy_struct.mode = 0;
-
     /* copy also acks to the kernel waking the stalled thread up
      * TODO: We can inhibit that ack and only do it if it was requested
      * which would be slightly cheaper, but we'd have to be careful
      * of the order of updating our page state.
      */
-    if (ioctl(mis->userfault_fd, UFFDIO_COPY, &copy_struct)) {
+    if (qemu_ufd_copy_ioctl(mis->userfault_fd, host, from, pagesize)) {
         int e = errno;
         error_report("%s: %s copy host: %p from: %p (size: %zd)",
                      __func__, strerror(e), host, from, pagesize);
@@ -601,12 +614,7 @@ int postcopy_place_page_zero(MigrationIncomingState *mis, void *host,
     trace_postcopy_place_page_zero(host);
 
     if (qemu_ram_pagesize(rb) == getpagesize()) {
-        struct uffdio_zeropage zero_struct;
-        zero_struct.range.start = (uint64_t)(uintptr_t)host;
-        zero_struct.range.len = getpagesize();
-        zero_struct.mode = 0;
-
-        if (ioctl(mis->userfault_fd, UFFDIO_ZEROPAGE, &zero_struct)) {
+        if (qemu_ufd_copy_ioctl(mis->userfault_fd, host, NULL, getpagesize())) {
             int e = errno;
             error_report("%s: %s zero host: %p",
                          __func__, strerror(e), host);
-- 
1.8.3.1

[Qemu-devel] [PATCH v7 3/3] migration: add bitmap for received page

[Alexey Perevalov]

This patch adds ability to track down already received
pages, it's necessary for calculation vCPU block time in
postcopy migration feature, maybe for restore after
postcopy migration failure.
Also it's necessary to solve shared memory issue in
postcopy livemigration. Information about received pages
will be transferred to the software virtual bridge
(e.g. OVS-VSWITCHD), to avoid fallocate (unmap) for
already received pages. fallocate syscall is required for
remmaped shared memory, due to remmaping itself blocks
ioctl(UFFDIO_COPY, ioctl in this case will end with EEXIT
error (struct page is exists after remmap).

Bitmap is placed into RAMBlock as another postcopy/precopy
related bitmaps.

Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
---
 include/exec/ram_addr.h  | 10 ++++++++++
 migration/postcopy-ram.c | 16 +++++++++++-----
 migration/ram.c          | 43 ++++++++++++++++++++++++++++++++++++++++---
 migration/ram.h          |  6 ++++++
 4 files changed, 67 insertions(+), 8 deletions(-)

diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h
index 73d1bea..af5bf26 100644
--- a/include/exec/ram_addr.h
+++ b/include/exec/ram_addr.h
@@ -47,6 +47,8 @@ struct RAMBlock {
      * of the postcopy phase
      */
     unsigned long *unsentmap;
+    /* bitmap of already received pages in postcopy */
+    unsigned long *receivedmap;
 };
 
 static inline bool offset_in_ramblock(RAMBlock *b, ram_addr_t offset)
@@ -60,6 +62,14 @@ static inline void *ramblock_ptr(RAMBlock *block, ram_addr_t offset)
     return (char *)block->host + offset;
 }
 
+static inline unsigned long int ramblock_recv_bitmap_offset(void *host_addr,
+                                                            RAMBlock *rb)
+{
+    uint64_t host_addr_offset =
+            (uint64_t)(uintptr_t)(host_addr - (void *)rb->host);
+    return host_addr_offset >> TARGET_PAGE_BITS;
+}
+
 long qemu_getrampagesize(void);
 unsigned long last_ram_page(void);
 RAMBlock *qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c
index be497bb..276ce12 100644
--- a/migration/postcopy-ram.c
+++ b/migration/postcopy-ram.c
@@ -560,22 +560,27 @@ int postcopy_ram_enable_notify(MigrationIncomingState *mis)
 }
 
 static int qemu_ufd_copy_ioctl(int userfault_fd, void *host_addr,
-        void *from_addr, uint64_t pagesize)
+                               void *from_addr, uint64_t pagesize, RAMBlock *rb)
 {
+    int ret;
     if (from_addr) {
         struct uffdio_copy copy_struct;
         copy_struct.dst = (uint64_t)(uintptr_t)host_addr;
         copy_struct.src = (uint64_t)(uintptr_t)from_addr;
         copy_struct.len = pagesize;
         copy_struct.mode = 0;
-        return ioctl(userfault_fd, UFFDIO_COPY, &copy_struct);
+        ret = ioctl(userfault_fd, UFFDIO_COPY, &copy_struct);
     } else {
         struct uffdio_zeropage zero_struct;
         zero_struct.range.start = (uint64_t)(uintptr_t)host_addr;
         zero_struct.range.len = pagesize;
         zero_struct.mode = 0;
-        return ioctl(userfault_fd, UFFDIO_ZEROPAGE, &zero_struct);
+        ret = ioctl(userfault_fd, UFFDIO_ZEROPAGE, &zero_struct);
+    }
+    if (!ret) {
+        ramblock_recv_bitmap_set(host_addr, rb);
     }
+    return ret;
 }
 
 /*
@@ -592,7 +597,7 @@ int postcopy_place_page(MigrationIncomingState *mis, void *host, void *from,
      * which would be slightly cheaper, but we'd have to be careful
      * of the order of updating our page state.
      */
-    if (qemu_ufd_copy_ioctl(mis->userfault_fd, host, from, pagesize)) {
+    if (qemu_ufd_copy_ioctl(mis->userfault_fd, host, from, pagesize, rb)) {
         int e = errno;
         error_report("%s: %s copy host: %p from: %p (size: %zd)",
                      __func__, strerror(e), host, from, pagesize);
@@ -614,7 +619,8 @@ int postcopy_place_page_zero(MigrationIncomingState *mis, void *host,
     trace_postcopy_place_page_zero(host);
 
     if (qemu_ram_pagesize(rb) == getpagesize()) {
-        if (qemu_ufd_copy_ioctl(mis->userfault_fd, host, NULL, getpagesize())) {
+        if (qemu_ufd_copy_ioctl(mis->userfault_fd, host, NULL, getpagesize(),
+                                rb)) {
             int e = errno;
             error_report("%s: %s zero host: %p",
                          __func__, strerror(e), host);
diff --git a/migration/ram.c b/migration/ram.c
index 9cc1b17..dfbb36b 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -147,6 +147,32 @@ out:
     return ret;
 }
 
+void ramblock_recv_map_init(void)
+{
+    RAMBlock *rb;
+
+    RAMBLOCK_FOREACH(rb) {
+        assert(!rb->receivedmap);
+        rb->receivedmap = bitmap_new(rb->max_length >> TARGET_PAGE_BITS);
+    }
+}
+
+int ramblock_recv_bitmap_test(void *host_addr, RAMBlock *rb)
+{
+    return test_bit(ramblock_recv_bitmap_offset(host_addr, rb),
+                    rb->receivedmap);
+}
+
+void ramblock_recv_bitmap_set(void *host_addr, RAMBlock *rb)
+{
+    set_bit_atomic(ramblock_recv_bitmap_offset(host_addr, rb), rb->receivedmap);
+}
+
+void ramblock_recv_bitmap_clear(void *host_addr, RAMBlock *rb)
+{
+    clear_bit(ramblock_recv_bitmap_offset(host_addr, rb), rb->receivedmap);
+}
+
 /*
  * An outstanding page request, on the source, having been received
  * and queued
@@ -1793,6 +1819,8 @@ int ram_discard_range(const char *rbname, uint64_t start, size_t length)
         goto err;
     }
 
+    bitmap_clear(rb->receivedmap, start >> TARGET_PAGE_BITS,
+                 length >> TARGET_PAGE_BITS);
     ret = ram_block_discard_range(rb, start, length);
 
 err:
@@ -2324,13 +2352,20 @@ static int ram_load_setup(QEMUFile *f, void *opaque)
 {
     xbzrle_load_setup();
     compress_threads_load_setup();
+    ramblock_recv_map_init();
     return 0;
 }
 
 static int ram_load_cleanup(void *opaque)
 {
+    RAMBlock *rb;
     xbzrle_load_cleanup();
     compress_threads_load_cleanup();
+
+    RAMBLOCK_FOREACH(rb) {
+        g_free(rb->receivedmap);
+        rb->receivedmap = NULL;
+    }
     return 0;
 }
 
@@ -2521,6 +2556,7 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id)
         ram_addr_t addr, total_ram_bytes;
         void *host = NULL;
         uint8_t ch;
+        RAMBlock *rb = NULL;
 
         addr = qemu_get_be64(f);
         flags = addr & ~TARGET_PAGE_MASK;
@@ -2537,15 +2573,16 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id)
 
         if (flags & (RAM_SAVE_FLAG_ZERO | RAM_SAVE_FLAG_PAGE |
                      RAM_SAVE_FLAG_COMPRESS_PAGE | RAM_SAVE_FLAG_XBZRLE)) {
-            RAMBlock *block = ram_block_from_stream(f, flags);
+            rb = ram_block_from_stream(f, flags);
 
-            host = host_from_ram_block_offset(block, addr);
+            host = host_from_ram_block_offset(rb, addr);
             if (!host) {
                 error_report("Illegal RAM offset " RAM_ADDR_FMT, addr);
                 ret = -EINVAL;
                 break;
             }
-            trace_ram_load_loop(block->idstr, (uint64_t)addr, flags, host);
+            ramblock_recv_bitmap_set(host, rb);
+            trace_ram_load_loop(rb->idstr, (uint64_t)addr, flags, host);
         }
 
         switch (flags & ~RAM_SAVE_FLAG_CONTINUE) {
diff --git a/migration/ram.h b/migration/ram.h
index c081fde..98d68df 100644
--- a/migration/ram.h
+++ b/migration/ram.h
@@ -52,4 +52,10 @@ int ram_discard_range(const char *block_name, uint64_t start, size_t length);
 int ram_postcopy_incoming_init(MigrationIncomingState *mis);
 
 void ram_handle_compressed(void *host, uint8_t ch, uint64_t size);
+
+void ramblock_recv_map_init(void);
+int ramblock_recv_bitmap_test(void *host_addr, RAMBlock *rb);
+void ramblock_recv_bitmap_set(void *host_addr, RAMBlock *rb);
+void ramblock_recv_bitmap_clear(void *host_addr, RAMBlock *rb);
+
 #endif
-- 
1.8.3.1

Re: [Qemu-devel] [PATCH v7 3/3] migration: add bitmap for received page

[Peter Xu]

On Fri, Jun 30, 2017 at 06:18:30AM -0400, Alexey Perevalov wrote:
> This patch adds ability to track down already received
> pages, it's necessary for calculation vCPU block time in
> postcopy migration feature, maybe for restore after
> postcopy migration failure.
> Also it's necessary to solve shared memory issue in
> postcopy livemigration. Information about received pages
> will be transferred to the software virtual bridge
> (e.g. OVS-VSWITCHD), to avoid fallocate (unmap) for
> already received pages. fallocate syscall is required for
> remmaped shared memory, due to remmaping itself blocks
> ioctl(UFFDIO_COPY, ioctl in this case will end with EEXIT
> error (struct page is exists after remmap).
> 
> Bitmap is placed into RAMBlock as another postcopy/precopy
> related bitmaps.
> 
> Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
> ---
>  include/exec/ram_addr.h  | 10 ++++++++++
>  migration/postcopy-ram.c | 16 +++++++++++-----
>  migration/ram.c          | 43 ++++++++++++++++++++++++++++++++++++++++---
>  migration/ram.h          |  6 ++++++
>  4 files changed, 67 insertions(+), 8 deletions(-)
> 
> diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h
> index 73d1bea..af5bf26 100644
> --- a/include/exec/ram_addr.h
> +++ b/include/exec/ram_addr.h
> @@ -47,6 +47,8 @@ struct RAMBlock {
>       * of the postcopy phase
>       */
>      unsigned long *unsentmap;
> +    /* bitmap of already received pages in postcopy */
> +    unsigned long *receivedmap;
>  };
>  
>  static inline bool offset_in_ramblock(RAMBlock *b, ram_addr_t offset)
> @@ -60,6 +62,14 @@ static inline void *ramblock_ptr(RAMBlock *block, ram_addr_t offset)
>      return (char *)block->host + offset;
>  }
>  
> +static inline unsigned long int ramblock_recv_bitmap_offset(void *host_addr,
> +                                                            RAMBlock *rb)
> +{
> +    uint64_t host_addr_offset =
> +            (uint64_t)(uintptr_t)(host_addr - (void *)rb->host);
> +    return host_addr_offset >> TARGET_PAGE_BITS;
> +}
> +
>  long qemu_getrampagesize(void);
>  unsigned long last_ram_page(void);
>  RAMBlock *qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
> diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c
> index be497bb..276ce12 100644
> --- a/migration/postcopy-ram.c
> +++ b/migration/postcopy-ram.c
> @@ -560,22 +560,27 @@ int postcopy_ram_enable_notify(MigrationIncomingState *mis)
>  }
>  
>  static int qemu_ufd_copy_ioctl(int userfault_fd, void *host_addr,
> -        void *from_addr, uint64_t pagesize)
> +                               void *from_addr, uint64_t pagesize, RAMBlock *rb)
>  {
> +    int ret;
>      if (from_addr) {
>          struct uffdio_copy copy_struct;
>          copy_struct.dst = (uint64_t)(uintptr_t)host_addr;
>          copy_struct.src = (uint64_t)(uintptr_t)from_addr;
>          copy_struct.len = pagesize;
>          copy_struct.mode = 0;
> -        return ioctl(userfault_fd, UFFDIO_COPY, &copy_struct);
> +        ret = ioctl(userfault_fd, UFFDIO_COPY, &copy_struct);
>      } else {
>          struct uffdio_zeropage zero_struct;
>          zero_struct.range.start = (uint64_t)(uintptr_t)host_addr;
>          zero_struct.range.len = pagesize;
>          zero_struct.mode = 0;
> -        return ioctl(userfault_fd, UFFDIO_ZEROPAGE, &zero_struct);
> +        ret = ioctl(userfault_fd, UFFDIO_ZEROPAGE, &zero_struct);
> +    }
> +    if (!ret) {
> +        ramblock_recv_bitmap_set(host_addr, rb);
>      }
> +    return ret;
>  }
>  
>  /*
> @@ -592,7 +597,7 @@ int postcopy_place_page(MigrationIncomingState *mis, void *host, void *from,
>       * which would be slightly cheaper, but we'd have to be careful
>       * of the order of updating our page state.
>       */
> -    if (qemu_ufd_copy_ioctl(mis->userfault_fd, host, from, pagesize)) {
> +    if (qemu_ufd_copy_ioctl(mis->userfault_fd, host, from, pagesize, rb)) {
>          int e = errno;
>          error_report("%s: %s copy host: %p from: %p (size: %zd)",
>                       __func__, strerror(e), host, from, pagesize);
> @@ -614,7 +619,8 @@ int postcopy_place_page_zero(MigrationIncomingState *mis, void *host,
>      trace_postcopy_place_page_zero(host);
>  
>      if (qemu_ram_pagesize(rb) == getpagesize()) {
> -        if (qemu_ufd_copy_ioctl(mis->userfault_fd, host, NULL, getpagesize())) {
> +        if (qemu_ufd_copy_ioctl(mis->userfault_fd, host, NULL, getpagesize(),
> +                                rb)) {
>              int e = errno;
>              error_report("%s: %s zero host: %p",
>                           __func__, strerror(e), host);
> diff --git a/migration/ram.c b/migration/ram.c
> index 9cc1b17..dfbb36b 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -147,6 +147,32 @@ out:
>      return ret;
>  }
>  
> +void ramblock_recv_map_init(void)
> +{
> +    RAMBlock *rb;
> +
> +    RAMBLOCK_FOREACH(rb) {
> +        assert(!rb->receivedmap);
> +        rb->receivedmap = bitmap_new(rb->max_length >> TARGET_PAGE_BITS);
> +    }
> +}
> +
> +int ramblock_recv_bitmap_test(void *host_addr, RAMBlock *rb)
> +{
> +    return test_bit(ramblock_recv_bitmap_offset(host_addr, rb),
> +                    rb->receivedmap);
> +}
> +
> +void ramblock_recv_bitmap_set(void *host_addr, RAMBlock *rb)
> +{
> +    set_bit_atomic(ramblock_recv_bitmap_offset(host_addr, rb), rb->receivedmap);
> +}
> +
> +void ramblock_recv_bitmap_clear(void *host_addr, RAMBlock *rb)
> +{
> +    clear_bit(ramblock_recv_bitmap_offset(host_addr, rb), rb->receivedmap);
> +}
> +
>  /*
>   * An outstanding page request, on the source, having been received
>   * and queued
> @@ -1793,6 +1819,8 @@ int ram_discard_range(const char *rbname, uint64_t start, size_t length)
>          goto err;
>      }
>  
> +    bitmap_clear(rb->receivedmap, start >> TARGET_PAGE_BITS,
> +                 length >> TARGET_PAGE_BITS);
>      ret = ram_block_discard_range(rb, start, length);
>  
>  err:
> @@ -2324,13 +2352,20 @@ static int ram_load_setup(QEMUFile *f, void *opaque)
>  {
>      xbzrle_load_setup();
>      compress_threads_load_setup();
> +    ramblock_recv_map_init();
>      return 0;
>  }
>  
>  static int ram_load_cleanup(void *opaque)
>  {
> +    RAMBlock *rb;
>      xbzrle_load_cleanup();
>      compress_threads_load_cleanup();
> +
> +    RAMBLOCK_FOREACH(rb) {
> +        g_free(rb->receivedmap);
> +        rb->receivedmap = NULL;
> +    }
>      return 0;
>  }

Yeah, this looks much better. Thanks. Though I may not bother export
ramblock_recv_map_init(), but it's ok.

>  
> @@ -2521,6 +2556,7 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id)
>          ram_addr_t addr, total_ram_bytes;
>          void *host = NULL;
>          uint8_t ch;
> +        RAMBlock *rb = NULL;
>  
>          addr = qemu_get_be64(f);
>          flags = addr & ~TARGET_PAGE_MASK;
> @@ -2537,15 +2573,16 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id)
>  
>          if (flags & (RAM_SAVE_FLAG_ZERO | RAM_SAVE_FLAG_PAGE |
>                       RAM_SAVE_FLAG_COMPRESS_PAGE | RAM_SAVE_FLAG_XBZRLE)) {
> -            RAMBlock *block = ram_block_from_stream(f, flags);
> +            rb = ram_block_from_stream(f, flags);
>  
> -            host = host_from_ram_block_offset(block, addr);
> +            host = host_from_ram_block_offset(rb, addr);
>              if (!host) {
>                  error_report("Illegal RAM offset " RAM_ADDR_FMT, addr);
>                  ret = -EINVAL;
>                  break;
>              }
> -            trace_ram_load_loop(block->idstr, (uint64_t)addr, flags, host);
> +            ramblock_recv_bitmap_set(host, rb);

If we move this line here, then we can keep the above *block
definition, then no need to touch other lines as well, so only one new
line addition is needed in ram_load.

> +            trace_ram_load_loop(rb->idstr, (uint64_t)addr, flags, host);
>          }
>  
>          switch (flags & ~RAM_SAVE_FLAG_CONTINUE) {
> diff --git a/migration/ram.h b/migration/ram.h
> index c081fde..98d68df 100644
> --- a/migration/ram.h
> +++ b/migration/ram.h
> @@ -52,4 +52,10 @@ int ram_discard_range(const char *block_name, uint64_t start, size_t length);
>  int ram_postcopy_incoming_init(MigrationIncomingState *mis);
>  
>  void ram_handle_compressed(void *host, uint8_t ch, uint64_t size);
> +
> +void ramblock_recv_map_init(void);
> +int ramblock_recv_bitmap_test(void *host_addr, RAMBlock *rb);
> +void ramblock_recv_bitmap_set(void *host_addr, RAMBlock *rb);
> +void ramblock_recv_bitmap_clear(void *host_addr, RAMBlock *rb);
> +
>  #endif
> -- 
> 1.8.3.1
> 

Only trivial nitpicks, maybe no need to repost? Anyway:

Reviewed-by: Peter Xu <peterx@redhat.com>

-- 
Peter Xu