Re: [PATCH v3] tools/sched_ext: Add SCX_OPS_OPEN_OPTS for schedulers using open opts

[Andrea Righi <arighi@nvidia.com>]

On Mon, Sep 28, 2026 at 11:09:55AM +0800, Fuyu Zhao wrote:
> Add SCX_OPS_OPEN_OPTS() and SCX_OPS_CID_OPEN_OPTS() to allow sched_ext
> schedulers to pass bpf_object_open_opts when opening BPF skeletons.
> 
> This allows sched_ext schedulers using open opts to retain the existing
> compatibility handling instead of bypassing it.
> 
> Signed-off-by: Fuyu Zhao <zhaofuyu@vivo.com>

Reviewed-by: Andrea Righi <arighi@nvidia.com>

Thanks,
-Andrea

> ---
> v3:
> - Add SCX_OPS_CID_OPEN_OPTS() to support open opts for
>   SCX_OPS_CID_OPEN() (Tejun).
> 
> v2:
> - Link: https://lore.kernel.org/sched-ext/20260923035613.20099-1-zhaofuyu@vivo.com/
> - Make SCX_OPS_OPEN() call SCX_OPS_OPEN_OPTS() with 0 as the opts
>   argument (Tejun).
> 
> v1:
> - Link: https://lore.kernel.org/sched-ext/20260922031618.2858-1-zhaofuyu@vivo.com/
> ---
>  tools/sched_ext/include/scx/compat.h | 16 +++++++++++-----
>  1 file changed, 11 insertions(+), 5 deletions(-)
> 
> diff --git a/tools/sched_ext/include/scx/compat.h b/tools/sched_ext/include/scx/compat.h
> index d2e4384df..3ae6e0ef1 100644
> --- a/tools/sched_ext/include/scx/compat.h
> +++ b/tools/sched_ext/include/scx/compat.h
> @@ -177,23 +177,23 @@ static inline long scx_hotplug_seq(void)
>   * - v7.1:  ops.sub_attach(), ops.sub_detach(), ops.sub_cgroup_id
>   * - v7.3:  ops.rescue_bandwidth_ppt, ops.rescue_quantum_us
>   */
> -#define __SCX_OPS_OPEN(__ops_name, __scx_name, __ops_struct) ({			\
> +#define __SCX_OPS_OPEN(__ops_name, __scx_name, __ops_struct, __opts) ({		\
>  	struct __scx_name *__oskel;						\
>  										\
>  	SCX_BUG_ON(!__COMPAT_struct_has_field(__ops_struct, "dump"),		\
>  		   __ops_struct ".dump() missing, kernel too old?");		\
>  										\
> -	__oskel = __scx_name##__open();						\
> +	__oskel = __scx_name##__open_opts(__opts);				\
>  	SCX_BUG_ON(!__oskel, "Could not open " #__scx_name);			\
>  	__oskel->struct_ops.__ops_name->hotplug_seq = scx_hotplug_seq();	\
>  	SCX_ENUM_INIT(__oskel);							\
>  	__oskel;								\
>  })
>  
> -#define SCX_OPS_OPEN(__ops_name, __scx_name) ({					\
> +#define SCX_OPS_OPEN_OPTS(__ops_name, __scx_name, __opts) ({			\
>  	struct __scx_name *__skel;						\
>  										\
> -	__skel = __SCX_OPS_OPEN(__ops_name, __scx_name, "sched_ext_ops");	\
> +	__skel = __SCX_OPS_OPEN(__ops_name, __scx_name, "sched_ext_ops", __opts); \
>  	if (__skel->struct_ops.__ops_name->cgroup_set_bandwidth &&		\
>  	    !__COMPAT_struct_has_field("sched_ext_ops", "cgroup_set_bandwidth")) { \
>  		fprintf(stderr, "WARNING: kernel doesn't support ops.cgroup_set_bandwidth()\n"); \
> @@ -232,12 +232,18 @@ static inline long scx_hotplug_seq(void)
>  	__skel; 								\
>  })
>  
> +#define SCX_OPS_OPEN(__ops_name, __scx_name)					\
> +	SCX_OPS_OPEN_OPTS(__ops_name, __scx_name, 0)
> +
>  /*
>   * Open a cid-form (struct sched_ext_ops_cid) skeleton. The cid form postdates
>   * every op the load-time fix-ups above handle, so none of them apply.
>   */
> +#define SCX_OPS_CID_OPEN_OPTS(__ops_name, __scx_name, __opts)			\
> +	__SCX_OPS_OPEN(__ops_name, __scx_name, "sched_ext_ops_cid", __opts)
> +
>  #define SCX_OPS_CID_OPEN(__ops_name, __scx_name)				\
> -	__SCX_OPS_OPEN(__ops_name, __scx_name, "sched_ext_ops_cid")
> +	SCX_OPS_CID_OPEN_OPTS(__ops_name, __scx_name, 0)
>  
>  /*
>   * Associate non-struct_ops BPF programs with the scheduler's struct_ops map so
> -- 
> 2.34.1
>