[CRIU] [PATCH] aio: Add plugin for waiting AIO in-flight reqs

[Kirill Tkhai]

This should go on top of "[PATCH] Add pr_info_once()"

On 05.04.2016 13:10, Kirill Tkhai wrote:
> This is possibility to wait AIO in-flight reqs before
> we collect AIO rings info.
> 
> Signed-off-by: Kirill Tkhai <ktkhai at virtuozzo.com>
> ---
>  criu/aio.c                 |   13 +++++++++++--
>  criu/cr-dump.c             |    2 +-
>  criu/include/aio.h         |    2 +-
>  criu/include/criu-plugin.h |    3 +++
>  4 files changed, 16 insertions(+), 4 deletions(-)
> 
> diff --git a/criu/aio.c b/criu/aio.c
> index 888a640..6bee66d 100644
> --- a/criu/aio.c
> +++ b/criu/aio.c
> @@ -3,6 +3,7 @@
>  #include <stdbool.h>
>  #include "vma.h"
>  #include "xmalloc.h"
> +#include "plugin.h"
>  #include "aio.h"
>  #include "parasite.h"
>  #include "parasite-syscall.h"
> @@ -70,12 +71,12 @@ unsigned long aio_rings_args_size(struct vm_area_list *vmas)
>  		vmas->nr_aios * sizeof(struct parasite_aio);
>  }
>  
> -int parasite_collect_aios(struct parasite_ctl *ctl, struct vm_area_list *vmas)
> +int parasite_collect_aios(struct parasite_ctl *ctl, pid_t pid, struct vm_area_list *vmas)
>  {
>  	struct vma_area *vma;
>  	struct parasite_check_aios_args *aa;
>  	struct parasite_aio *pa;
> -	int i;
> +	int i, ret;
>  
>  	if (!vmas->nr_aios)
>  		return 0;
> @@ -106,6 +107,14 @@ int parasite_collect_aios(struct parasite_ctl *ctl, struct vm_area_list *vmas)
>  	}
>  	aa->nr_rings = vmas->nr_aios;
>  
> +	ret = run_plugins(AIO_WAIT_REQS, pid);
> +	if (ret == -ENOTSUP) {
> +		pr_info_once("AIO_WAIT_REQS plugin was not found\n");
> +	} else if (ret < 0) {
> +		pr_err("Can't execute AIO_WAIT_REQS plugin: ret=%d\n", ret);
> +		return -1;
> +	}
> +
>  	if (parasite_execute_daemon(PARASITE_CMD_CHECK_AIOS, ctl))
>  		return -1;
>  
> diff --git a/criu/cr-dump.c b/criu/cr-dump.c
> index 6d3ccd1..623e6ed 100644
> --- a/criu/cr-dump.c
> +++ b/criu/cr-dump.c
> @@ -1263,7 +1263,7 @@ static int dump_one_task(struct pstree_item *item)
>  		goto err_cure_imgset;
>  	}
>  
> -	ret = parasite_collect_aios(parasite_ctl, &vmas); /* FIXME -- merge with above */
> +	ret = parasite_collect_aios(parasite_ctl, pid, &vmas); /* FIXME -- merge with above */
>  	if (ret) {
>  		pr_err("Failed to check aio rings (pid: %d)\n", pid);
>  		goto err_cure_imgset;
> diff --git a/criu/include/aio.h b/criu/include/aio.h
> index 1e08775..3124164 100644
> --- a/criu/include/aio.h
> +++ b/criu/include/aio.h
> @@ -6,7 +6,7 @@
>  int dump_aio_ring(MmEntry *mme, struct vma_area *vma);
>  void free_aios(MmEntry *mme);
>  struct parasite_ctl;
> -int parasite_collect_aios(struct parasite_ctl *, struct vm_area_list *);
> +int parasite_collect_aios(struct parasite_ctl *, pid_t pid, struct vm_area_list *);
>  unsigned long aio_rings_args_size(struct vm_area_list *);
>  
>  struct aio_ring {
> diff --git a/criu/include/criu-plugin.h b/criu/include/criu-plugin.h
> index b76f5f8..1d06a94 100644
> --- a/criu/include/criu-plugin.h
> +++ b/criu/include/criu-plugin.h
> @@ -50,6 +50,8 @@ enum {
>  
>  	CR_PLUGIN_HOOK__DUMP_EXT_LINK		= 6,
>  
> +	CR_PLUGIN_HOOK__AIO_WAIT_REQS		= 7,
> +
>  	CR_PLUGIN_HOOK__MAX
>  };
>  
> @@ -63,6 +65,7 @@ DECLARE_PLUGIN_HOOK_ARGS(CR_PLUGIN_HOOK__RESTORE_EXT_FILE, int id);
>  DECLARE_PLUGIN_HOOK_ARGS(CR_PLUGIN_HOOK__DUMP_EXT_MOUNT, char *mountpoint, int id);
>  DECLARE_PLUGIN_HOOK_ARGS(CR_PLUGIN_HOOK__RESTORE_EXT_MOUNT, int id, char *mountpoint, char *old_root, int *is_file);
>  DECLARE_PLUGIN_HOOK_ARGS(CR_PLUGIN_HOOK__DUMP_EXT_LINK, int index, int type, char *kind);
> +DECLARE_PLUGIN_HOOK_ARGS(CR_PLUGIN_HOOK__AIO_WAIT_REQS, pid_t pid);
>  
>  enum {
>  	CR_PLUGIN_STAGE__DUMP,
>