[CRIU] Re: [PATCH] restore: Order file restoring by their type

[Pavel Emelyanov]

On 04/28/2012 05:36 PM, Cyrill Gorcunov wrote:
> We need the files being restored in order of their
> type. In particular when we restore eventpoll file
> we expect every file descriptor the epoll watches on
> is already created and opened.

I'd explicitly restore only eventpoll files at the very
end instead.

> Signed-off-by: Cyrill Gorcunov <gorcunov at openvz.org>
> ---
>  files.c           |   27 +++++++++++++++++++--------
>  include/crtools.h |    2 +-
>  2 files changed, 20 insertions(+), 9 deletions(-)
> 
> diff --git a/files.c b/files.c
> index 2fd4ec0..b5e7508 100644
> --- a/files.c
> +++ b/files.c
> @@ -373,9 +373,11 @@ static int collect_fd(int pid, struct fdinfo_entry *e, struct list_head *fds)
>  int prepare_fd_pid(int pid, struct rst_info *rst_info)
>  {
>  	int fdinfo_fd, ret = 0;
> +	unsigned int i;
>  	u32 type = 0;
>  
> -	INIT_LIST_HEAD(&rst_info->fds);
> +	for (i = 0; i < ARRAY_SIZE(rst_info->fds); i++)
> +		INIT_LIST_HEAD(&rst_info->fds[i]);
>  
>  	fdinfo_fd = open_image_ro(CR_FD_FDINFO, pid);
>  	if (fdinfo_fd < 0) {
> @@ -391,8 +393,14 @@ int prepare_fd_pid(int pid, struct rst_info *rst_info)
>  		ret = read_img_eof(fdinfo_fd, &e);
>  		if (ret <= 0)
>  			break;
> +		if (e.type >= FD_INFO_MAX) {
> +			ret = -1;
> +			pr_err("Unexpected file type found %d [%#x]\n",
> +			       e.fd, e.type);
> +			break;
> +		}
>  
> -		ret = collect_fd(pid, &e, &rst_info->fds);
> +		ret = collect_fd(pid, &e, &rst_info->fds[e.type]);
>  		if (ret < 0)
>  			break;
>  	}
> @@ -648,18 +656,21 @@ static int open_fdinfo(int pid, struct fdinfo_entry *fe, int state)
>  int prepare_fds(struct pstree_item *me)
>  {
>  	u32 type = 0, ret;
> -	int state;
> +	int state, i;
>  	struct fdinfo_list_entry *fle;
>  	int nr = 0;
>  
>  	pr_info("%d: Opening fdinfo-s\n", me->pid);
>  
> -	for (state = 0; state < FD_STATE_MAX; state++)
> -		list_for_each_entry(fle, &me->rst->fds, ps_list) {
> -			ret = open_fdinfo(me->pid, &fle->fe, state);
> -			if (ret)
> -				goto done;
> +	for (state = 0; state < FD_STATE_MAX; state++) {
> +		for (i = 0; i < (int)ARRAY_SIZE(me->rst->fds); i++) {
> +			list_for_each_entry(fle, &me->rst->fds[i], ps_list) {
> +				ret = open_fdinfo(me->pid, &fle->fe, state);
> +				if (ret)
> +					goto done;
> +			}
>  		}
> +	}
>  
>  	ret = run_unix_connections();
>  done:
> diff --git a/include/crtools.h b/include/crtools.h
> index 291c880..99bd69f 100644
> --- a/include/crtools.h
> +++ b/include/crtools.h
> @@ -193,7 +193,7 @@ struct vma_area {
>  #define vma_area_len(vma_area)		vma_entry_len(&((vma_area)->vma))
>  
>  struct rst_info {
> -	struct list_head	fds;
> +	struct list_head	fds[FD_INFO_MAX];
>  };
>  
>  struct pstree_item {