migration: update comments of migration bitmap

[Qemu-devel] [PATCH] migration: update comments of migration bitmap

Posted by Yi Wang 5 years ago

Since the ram bitmap and the unsent bitmap are split by RAMBlock
in commit 6b6712e, it's better to update the comments about them.

Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
---
 migration/ram.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/migration/ram.c b/migration/ram.c
index 1ca9ba7..24ab23d 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -1630,8 +1630,6 @@ static int save_xbzrle_page(RAMState *rs, uint8_t **current_data,
 /**
  * migration_bitmap_find_dirty: find the next dirty page from start
  *
- * Called with rcu_read_lock() to protect migration_bitmap
- *
  * Returns the byte offset within memory region of the start of a dirty page
  *
  * @rs: current RAM state
@@ -2681,7 +2679,7 @@ static void ram_save_cleanup(void *opaque)
     RAMBlock *block;
 
     /* caller have hold iothread lock or is in a bh, so there is
-     * no writing race against this migration_bitmap
+     * no writing race against the migration bitmap
      */
     memory_global_dirty_log_stop();
 
-- 
1.8.3.1

Re: [Qemu-devel] [PATCH] migration: update comments of migration bitmap

Posted by Dr. David Alan Gilbert 4 years, 11 months ago

* Yi Wang (wang.yi59@zte.com.cn) wrote:
> Since the ram bitmap and the unsent bitmap are split by RAMBlock
> in commit 6b6712e, it's better to update the comments about them.
> 
> Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

> ---
>  migration/ram.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/migration/ram.c b/migration/ram.c
> index 1ca9ba7..24ab23d 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -1630,8 +1630,6 @@ static int save_xbzrle_page(RAMState *rs, uint8_t **current_data,
>  /**
>   * migration_bitmap_find_dirty: find the next dirty page from start
>   *
> - * Called with rcu_read_lock() to protect migration_bitmap
> - *
>   * Returns the byte offset within memory region of the start of a dirty page
>   *
>   * @rs: current RAM state
> @@ -2681,7 +2679,7 @@ static void ram_save_cleanup(void *opaque)
>      RAMBlock *block;
>  
>      /* caller have hold iothread lock or is in a bh, so there is
> -     * no writing race against this migration_bitmap
> +     * no writing race against the migration bitmap
>       */
>      memory_global_dirty_log_stop();
>  
> -- 
> 1.8.3.1
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK

Re: [Qemu-devel] [PATCH] migration: update comments of migration bitmap

Posted by Dr. David Alan Gilbert 4 years, 11 months ago

* Yi Wang (wang.yi59@zte.com.cn) wrote:
> Since the ram bitmap and the unsent bitmap are split by RAMBlock
> in commit 6b6712e, it's better to update the comments about them.
> 
> Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>

Queued

> ---
>  migration/ram.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/migration/ram.c b/migration/ram.c
> index 1ca9ba7..24ab23d 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -1630,8 +1630,6 @@ static int save_xbzrle_page(RAMState *rs, uint8_t **current_data,
>  /**
>   * migration_bitmap_find_dirty: find the next dirty page from start
>   *
> - * Called with rcu_read_lock() to protect migration_bitmap
> - *
>   * Returns the byte offset within memory region of the start of a dirty page
>   *
>   * @rs: current RAM state
> @@ -2681,7 +2679,7 @@ static void ram_save_cleanup(void *opaque)
>      RAMBlock *block;
>  
>      /* caller have hold iothread lock or is in a bh, so there is
> -     * no writing race against this migration_bitmap
> +     * no writing race against the migration bitmap
>       */
>      memory_global_dirty_log_stop();
>  
> -- 
> 1.8.3.1
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK