Patchwork [V3,2/5] xen: Introduce xen_modified_memory.

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Submitter Anthony PERARD
Date Sept. 20, 2012, 11:12 a.m.
Message ID <1348139574-23324-3-git-send-email-anthony.perard@citrix.com>
Download mbox | patch
Permalink /patch/185377/
State New
Headers show

Comments

Anthony PERARD - Sept. 20, 2012, 11:12 a.m.
This function is to be used during live migration. Every write access to the
guest memory should call this funcion so the Xen tools knows which pages are
dirty.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
---
 hw/xen.h   |  1 +
 xen-all.c  | 21 +++++++++++++++++++++
 xen-stub.c |  4 ++++
 3 files changed, 26 insertions(+)
Stefano Stabellini - Sept. 20, 2012, 12:29 p.m.
On Thu, 20 Sep 2012, Anthony PERARD wrote:
> This function is to be used during live migration. Every write access to the
> guest memory should call this funcion so the Xen tools knows which pages are
> dirty.
> 
> Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
> ---
>  hw/xen.h   |  1 +
>  xen-all.c  | 21 +++++++++++++++++++++
>  xen-stub.c |  4 ++++
>  3 files changed, 26 insertions(+)
> 
> diff --git a/hw/xen.h b/hw/xen.h
> index e5926b7..d14e92d 100644
> --- a/hw/xen.h
> +++ b/hw/xen.h
> @@ -48,6 +48,7 @@ void xenstore_store_pv_console_info(int i, struct CharDriverState *chr);
>  struct MemoryRegion;
>  void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size,
>                     struct MemoryRegion *mr);
> +void xen_modified_memory(ram_addr_t start, ram_addr_t length);
>  #endif
>  
>  struct MemoryRegion;
> diff --git a/xen-all.c b/xen-all.c
> index f75ae9f..6250593 100644
> --- a/xen-all.c
> +++ b/xen-all.c
> @@ -1228,3 +1228,24 @@ void xen_shutdown_fatal_error(const char *fmt, ...)
>      /* destroy the domain */
>      qemu_system_shutdown_request();
>  }
> +
> +void xen_modified_memory(ram_addr_t start, ram_addr_t length)
> +{
> +    if (unlikely(xen_in_migration)) {
> +        int rc;
> +        ram_addr_t start_pfn, nb_pages;
> +
> +        if (length == 0) {
> +            length = TARGET_PAGE_SIZE;
> +        }
> +        start_pfn = start >> TARGET_PAGE_BITS;
> +        nb_pages = ((start + length + TARGET_PAGE_SIZE - 1) >> TARGET_PAGE_BITS)
> +            - start_pfn;
> +        rc = xc_hvm_modified_memory(xen_xc, xen_domid, start_pfn, nb_pages);
> +        if (rc) {
> +            fprintf(stderr, "%s failed for "RAM_ADDR_FMT" ("RAM_ADDR_FMT
> +                    "): %i, %s\n", __func__,
> +                    start, nb_pages, rc, strerror(-rc));

a would prefer a more sane way of splitting this sentence in lines
Anthony PERARD - Sept. 21, 2012, 2:29 p.m.
On Thu, Sep 20, 2012 at 1:29 PM, Stefano Stabellini
<stefano.stabellini@eu.citrix.com> wrote:
>
>> +void xen_modified_memory(ram_addr_t start, ram_addr_t length)
>> +{
>> +    if (unlikely(xen_in_migration)) {
>> +        int rc;
>> +        ram_addr_t start_pfn, nb_pages;
>> +
>> +        if (length == 0) {
>> +            length = TARGET_PAGE_SIZE;
>> +        }
>> +        start_pfn = start >> TARGET_PAGE_BITS;
>> +        nb_pages = ((start + length + TARGET_PAGE_SIZE - 1) >> TARGET_PAGE_BITS)
>> +            - start_pfn;
>> +        rc = xc_hvm_modified_memory(xen_xc, xen_domid, start_pfn, nb_pages);
>> +        if (rc) {
>> +            fprintf(stderr, "%s failed for "RAM_ADDR_FMT" ("RAM_ADDR_FMT
>> +                    "): %i, %s\n", __func__,
>> +                    start, nb_pages, rc, strerror(-rc));
>
> a would prefer a more sane way of splitting this sentence in lines

Will do.

Patch

diff --git a/hw/xen.h b/hw/xen.h
index e5926b7..d14e92d 100644
--- a/hw/xen.h
+++ b/hw/xen.h
@@ -48,6 +48,7 @@  void xenstore_store_pv_console_info(int i, struct CharDriverState *chr);
 struct MemoryRegion;
 void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size,
                    struct MemoryRegion *mr);
+void xen_modified_memory(ram_addr_t start, ram_addr_t length);
 #endif
 
 struct MemoryRegion;
diff --git a/xen-all.c b/xen-all.c
index f75ae9f..6250593 100644
--- a/xen-all.c
+++ b/xen-all.c
@@ -1228,3 +1228,24 @@  void xen_shutdown_fatal_error(const char *fmt, ...)
     /* destroy the domain */
     qemu_system_shutdown_request();
 }
+
+void xen_modified_memory(ram_addr_t start, ram_addr_t length)
+{
+    if (unlikely(xen_in_migration)) {
+        int rc;
+        ram_addr_t start_pfn, nb_pages;
+
+        if (length == 0) {
+            length = TARGET_PAGE_SIZE;
+        }
+        start_pfn = start >> TARGET_PAGE_BITS;
+        nb_pages = ((start + length + TARGET_PAGE_SIZE - 1) >> TARGET_PAGE_BITS)
+            - start_pfn;
+        rc = xc_hvm_modified_memory(xen_xc, xen_domid, start_pfn, nb_pages);
+        if (rc) {
+            fprintf(stderr, "%s failed for "RAM_ADDR_FMT" ("RAM_ADDR_FMT
+                    "): %i, %s\n", __func__,
+                    start, nb_pages, rc, strerror(-rc));
+        }
+    }
+}
diff --git a/xen-stub.c b/xen-stub.c
index 5e66ba8..9214392 100644
--- a/xen-stub.c
+++ b/xen-stub.c
@@ -59,3 +59,7 @@  void xen_register_framebuffer(MemoryRegion *mr)
 void qmp_xen_set_global_dirty_log(bool enable, Error **errp)
 {
 }
+
+void xen_modified_memory(ram_addr_t start, ram_addr_t length)
+{
+}