[CRIU] [PATCH 25/28] files: Add fake fle flag and close such fles after restore files

[Andrei Vagin]

On Mon, Jun 05, 2017 at 08:27:07PM +0300, Kirill Tkhai wrote:
> Allow to mark some fles as "fake" and close them, when they are not needed.
> 
> Signed-off-by: Kirill Tkhai <ktkhai at virtuozzo.com>
> ---
>  criu/files.c         |   14 ++++++++++++++
>  criu/include/files.h |    1 +
>  2 files changed, 15 insertions(+)
> 
> diff --git a/criu/files.c b/criu/files.c
> index a2b57ca01..f97b7a0a2 100644
> --- a/criu/files.c
> +++ b/criu/files.c
> @@ -710,6 +710,7 @@ static struct fdinfo_list_entry *alloc_fle(int pid, FdinfoEntry *fe)
>  	fle->pid = pid;
>  	fle->fe = fe;
>  	fle->received = 0;
> +	fle->fake = 0;
>  	fle->stage = FLE_INITIALIZED;
>  	fle->task = pstree_item_by_virt(pid);
>  	if (!fle->task) {
> @@ -1199,6 +1200,17 @@ static int open_fdinfos(struct pstree_item *me)
>  	return ret;
>  }
>  
> +static void close_fake_fdinfos(struct pstree_item *me)
> +{
> +	struct list_head *list = &rsti(me)->fds;
> +	struct fdinfo_list_entry *fle;
> +
> +	list_for_each_entry(fle, list, ps_list) {
> +		if (fle->fake)
> +			close(fle->fe->fd);
> +	}

Why we can't to close it immediately after sending it to all recipients?

> +}
> +
>  static struct inherit_fd *inherit_fd_lookup_fd(int fd, const char *caller);
>  
>  int close_old_fds(void)
> @@ -1268,6 +1280,8 @@ int prepare_fds(struct pstree_item *me)
>  	BUG_ON(current->pid->state == TASK_HELPER);
>  	ret = open_fdinfos(me);
>  
> +	close_fake_fdinfos(me);
> +
>  	if (rsti(me)->fdt)
>  		futex_inc_and_wake(&rsti(me)->fdt->fdt_lock);
>  out:
> diff --git a/criu/include/files.h b/criu/include/files.h
> index fd2d20761..fb47eb879 100644
> --- a/criu/include/files.h
> +++ b/criu/include/files.h
> @@ -80,6 +80,7 @@ struct fdinfo_list_entry {
>  	FdinfoEntry		*fe;
>  	u8			received:1;
>  	u8			stage:3;
> +	u8			fake:1;
>  };
>  
>  /* reports whether fd_a takes prio over fd_b */
>