[CRIU] [PATCH 2/5] page-server: Unify async/sync calls

[Mike Rapoport]

On Wed, Jun 14, 2017 at 01:14:46PM +0300, Pavel Emelyanov wrote:
> The newly introduced sync-read call may look exactly
> the same as its async pair by using the respective
> complete callback.
> 
> Signed-off-by: Pavel Emelyanov <xemul at virtuozzo.com>

Acked-by: Mike Rapoport <rppt at linux.vnet.ibm.com>

> ---
>  criu/include/page-xfer.h | 3 ++-
>  criu/page-xfer.c         | 9 +++++++--
>  criu/pagemap.c           | 8 ++------
>  3 files changed, 11 insertions(+), 9 deletions(-)
> 
> diff --git a/criu/include/page-xfer.h b/criu/include/page-xfer.h
> index 5d8dc81..4ccefee 100644
> --- a/criu/include/page-xfer.h
> +++ b/criu/include/page-xfer.h
> @@ -64,6 +64,7 @@ extern int request_remote_pages(int pid, unsigned long addr, int nr_pages);
>  typedef int (*ps_async_read_complete)(int pid, unsigned long vaddr, int nr_pages, void *);
>  extern int page_server_start_async_read(void *buf, int nr_pages,
>  		ps_async_read_complete complete, void *priv);
> -extern int page_server_start_sync_read(void *buf, int nr_pages, unsigned long *vaddr);
> +extern int page_server_start_sync_read(void *buf, int nr_pages,
> +		ps_async_read_complete complete, void *priv);
>  
>  #endif /* __CR_PAGE_XFER__H__ */
> diff --git a/criu/page-xfer.c b/criu/page-xfer.c
> index 761985a..067b7d3 100644
> --- a/criu/page-xfer.c
> +++ b/criu/page-xfer.c
> @@ -1204,20 +1204,25 @@ static int receive_remote_pages(int len, void *buf)
>  	return 0;
>  }
>  
> -int page_server_start_sync_read(void *buf, int nr, unsigned long *vaddr)
> +int page_server_start_sync_read(void *buf, int nr,
> +		ps_async_read_complete complete, void *priv)
>  {
>  	int ret, pid, new_nr;
> +	unsigned long vaddr;
>  
>  	/*
>  	 * Note, that for async remote page_read, the actual
>  	 * transfer happens in the lazy-pages daemon
>  	 */
> -	ret = receive_remote_pages_info(&new_nr, vaddr, &pid);
> +	ret = receive_remote_pages_info(&new_nr, &vaddr, &pid);
>  	if (ret == 0) {
>  		if (new_nr < 0 || new_nr > nr)
>  			return -1;
>  		ret = receive_remote_pages(nr * PAGE_SIZE, buf);
>  	}
>  
> +	if (ret == 0)
> +		ret = complete(pid, vaddr, nr, priv);
> +
>  	return ret;
>  }
> diff --git a/criu/pagemap.c b/criu/pagemap.c
> index 06264a1..8a2cce9 100644
> --- a/criu/pagemap.c
> +++ b/criu/pagemap.c
> @@ -474,12 +474,8 @@ static int maybe_read_page_remote(struct page_read *pr, unsigned long vaddr,
>  		return ret;
>  	if (flags & PR_ASYNC)
>  		return page_server_start_async_read(buf, nr, read_page_complete, pr);
> -
> -	ret = page_server_start_sync_read(buf, nr, &vaddr);
> -	if (ret == 0 && pr->io_complete)
> -		ret = pr->io_complete(pr, vaddr, nr);
> -
> -	return ret;
> +	else
> +		return page_server_start_sync_read(buf, nr, read_page_complete, pr);
>  }
>  
>  static int read_pagemap_page(struct page_read *pr, unsigned long vaddr, int nr,
> -- 
> 2.1.4
> 
> _______________________________________________
> CRIU mailing list
> CRIU at openvz.org
> https://lists.openvz.org/mailman/listinfo/criu