[LTP] [PATCH v9 2/2] tst_cgroup.c: Add a cgroup pseudo controller

[Cyril Hrubis]

Hi!
> For new test case such as kill01.c no need specific controller, it just
> need LTP cgroup library start work, so we need add a "cgroup" pseudo
> controller.

Can we please call it "base" controller? Or something better fitting?

> Signed-off-by: Wei Gao <wegao@suse.com>
> ---
>  lib/tst_cgroup.c | 47 ++++++++++++++++++++++++++++++++---------------
>  1 file changed, 32 insertions(+), 15 deletions(-)
> 
> diff --git a/lib/tst_cgroup.c b/lib/tst_cgroup.c
> index 77575431d..ed3e0758f 100644
> --- a/lib/tst_cgroup.c
> +++ b/lib/tst_cgroup.c
> @@ -94,9 +94,10 @@ enum cgroup_ctrl_indx {
>  	CTRL_MISC,
>  	CTRL_PERFEVENT,
>  	CTRL_DEBUG,
> -	CTRL_RDMA
> +	CTRL_RDMA,
> +	CTRL_PSEUDO
>  };
> -#define CTRLS_MAX CTRL_RDMA
> +#define CTRLS_MAX CTRL_PSEUDO
>  
>  /* At most we can have one cgroup V1 tree for each controller and one
>   * (empty) v2 tree.
> @@ -259,6 +260,10 @@ static const struct cgroup_file rdma_ctrl_files[] = {
>  	{ }
>  };
>  
> +static const struct cgroup_file pseudo_ctrl_files[] = {
> +	{ }
> +};
> +
>  #define CTRL_NAME_MAX 31
>  #define CGROUP_CTRL_MEMBER(x, y)[y] = { .ctrl_name = #x, .files = \
>  	x ## _ctrl_files, .ctrl_indx = y, NULL, 0 }
> @@ -282,6 +287,7 @@ static struct cgroup_ctrl controllers[] = {
>  	CGROUP_CTRL_MEMBER(perf_event, CTRL_PERFEVENT),
>  	CGROUP_CTRL_MEMBER(debug, CTRL_DEBUG),
>  	CGROUP_CTRL_MEMBER(rdma, CTRL_RDMA),
> +	CGROUP_CTRL_MEMBER(pseudo, CTRL_PSEUDO),
>  	{ }
>  };
>  
> @@ -798,6 +804,10 @@ void tst_cg_require(const char *const ctrl_name,
>  	const char *const cgsc = "cgroup.subtree_control";
>  	struct cgroup_ctrl *const ctrl = cgroup_find_ctrl(ctrl_name);
>  	struct cgroup_root *root;
> +	int pseudo = !strcmp(ctrl->ctrl_name, "pseudo");
> +
> +	if (pseudo && options->needs_ver != TST_CG_V2)
> +		tst_brk(TCONF, "pseudo control only support needs_ver TST_CG_V2!");
>  
>  	if (!ctrl) {
>  		tst_brk(TBROK, "'%s' controller is unknown to LTP", ctrl_name);
> @@ -827,6 +837,9 @@ void tst_cg_require(const char *const ctrl_name,
>  	if (options->needs_ver != TST_CG_V2)
>  		cgroup_mount_v1(ctrl);
>  
> +	if (pseudo)
> +		ctrl->ctrl_root = roots;
> +
>  	if (!ctrl->ctrl_root) {
>  		tst_brk(TCONF,
>  			"'%s' controller required, but not available",
> @@ -849,13 +862,13 @@ mkdirs:
>  			ctrl->ctrl_name);
>  	}
>  
> -	if (cgroup_ctrl_on_v2(ctrl)) {
> +	if (cgroup_ctrl_on_v2(ctrl) && !pseudo) {
>  		if (root->we_mounted_it) {
>  			SAFE_FILE_PRINTFAT(root->mnt_dir.dir_fd,
> -					   cgsc, "+%s", ctrl->ctrl_name);
> +					cgsc, "+%s", ctrl->ctrl_name);
>  		} else {
>  			tst_file_printfat(root->mnt_dir.dir_fd,
> -					  cgsc, "+%s", ctrl->ctrl_name);
> +					cgsc, "+%s", ctrl->ctrl_name);
>  		}
>  	}
>  
> @@ -864,15 +877,17 @@ mkdirs:
>  	else
>  		root->ltp_dir.ctrl_field |= root->mnt_dir.ctrl_field;
>  
> -	if (cgroup_ctrl_on_v2(ctrl)) {
> -		SAFE_FILE_PRINTFAT(root->ltp_dir.dir_fd,
> -				   cgsc, "+%s", ctrl->ctrl_name);
> -	} else {
> -		SAFE_FILE_PRINTFAT(root->ltp_dir.dir_fd,
> -				   "cgroup.clone_children", "%d", 1);
> +	if (!pseudo) {
> +		if (cgroup_ctrl_on_v2(ctrl)) {
> +			SAFE_FILE_PRINTFAT(root->ltp_dir.dir_fd,
> +					cgsc, "+%s", ctrl->ctrl_name);
> +		} else {
> +			SAFE_FILE_PRINTFAT(root->ltp_dir.dir_fd,
> +					"cgroup.clone_children", "%d", 1);
>  
> -		if (ctrl->ctrl_indx == CTRL_CPUSET)
> -			cgroup_copy_cpuset(root);
> +			if (ctrl->ctrl_indx == CTRL_CPUSET)
> +				cgroup_copy_cpuset(root);
> +		}
>  	}
>  
>  	cgroup_dir_mk(&root->ltp_dir, cgroup_ltp_drain_dir, &root->drain_dir);
> @@ -1050,8 +1065,10 @@ static void cgroup_group_add_dir(const struct tst_cg_group *const parent,
>  		if (!parent || dir->dir_root->ver == TST_CG_V1)
>  			continue;
>  
> -		SAFE_CG_PRINTF(parent, "cgroup.subtree_control",
> -				   "+%s", ctrl->ctrl_name);
> +		if (strcmp(ctrl->ctrl_name, "pseudo")) {
> +			SAFE_CG_PRINTF(parent, "cgroup.subtree_control",
> +					"+%s", ctrl->ctrl_name);
> +		}
>  	}
>  
>  	for (i = 0; cg->dirs[i]; i++)
> -- 
> 2.35.3
> 
> 
> -- 
> Mailing list info: https://lists.linux.it/listinfo/ltp

-- 
Cyril Hrubis
chrubis@suse.cz