sched: programmable: add bpf_sched_task_tag_of helper function

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I5KUFB
CVE: NA

--------------------------------

This helper function read the tag of the struct task.
The bpf prog obtains the tags to detect different workloads.
Signed-off-by: NChen Hui <judy.chenhui@huawei.com>
Signed-off-by: NRen Zhijie <renzhijie2@huawei.com>

include/uapi/linux/bpf.h

@@ -3785,6 +3785,13 @@ union bpf_attr {
  *	Return
  *		Task group tag, if CONFIG_CGROUP_SCHED enabled, 0 as default tag, or
  *		a negative error in case of failure.
+ *
+ * long bpf_sched_task_tag_of(struct task_struct *tsk)
+ *	Description
+ *		Return task tag of *tsk*.The bpf prog obtains the tags to detect
+ *		different workloads.
+ *	Return
+ *		Task tag, if used, 0 as default tag, or a negative error in case of failure.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\
@@ -3949,6 +3956,7 @@ union bpf_attr {
 	FN(sched_entity_to_cgrpid),		\
 	FN(sched_entity_belongs_to_cgrp),	\
 	FN(sched_tg_tag_of),	\
+	FN(sched_task_tag_of),	\
 	/* */
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper

kernel/bpf/helpers.c

@@ -659,6 +659,7 @@ const struct bpf_func_proto bpf_probe_read_user_str_proto __weak;
 const struct bpf_func_proto bpf_probe_read_kernel_proto __weak;
 const struct bpf_func_proto bpf_probe_read_kernel_str_proto __weak;
 const struct bpf_func_proto bpf_sched_tg_tag_of_proto __weak;
+const struct bpf_func_proto bpf_sched_task_tag_of_proto __weak;
 
 const struct bpf_func_proto *
 bpf_base_func_proto(enum bpf_func_id func_id)
@@ -700,6 +701,8 @@ bpf_base_func_proto(enum bpf_func_id func_id)
 		return &bpf_ringbuf_query_proto;
 	case BPF_FUNC_sched_tg_tag_of:
 		return &bpf_sched_tg_tag_of_proto;
+	case BPF_FUNC_sched_task_tag_of:
+		return &bpf_sched_task_tag_of_proto;
 	default:
 		break;
 	}

kernel/sched/bpf_sched.c

@@ -135,6 +135,23 @@ const struct bpf_func_proto bpf_sched_tg_tag_of_proto = {
 	.arg1_btf_id	= &btf_sched_tg_ids[0],
 };
 
+BPF_CALL_1(bpf_sched_task_tag_of, struct task_struct *, tsk)
+{
+	if (tsk == NULL)
+		return -EINVAL;
+	return tsk->tag;
+}
+
+BTF_ID_LIST_SINGLE(btf_sched_task_ids, struct, task_struct)
+
+const struct bpf_func_proto bpf_sched_task_tag_of_proto = {
+	.func		= bpf_sched_task_tag_of,
+	.gpl_only	= false,
+	.ret_type	= RET_INTEGER,
+	.arg1_type	= PTR_MAYBE_NULL | ARG_PTR_TO_BTF_ID,
+	.arg1_btf_id	= &btf_sched_task_ids[0],
+};
+
 static const struct bpf_func_proto *
 bpf_sched_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 {

tools/include/uapi/linux/bpf.h

@@ -3785,6 +3785,13 @@ union bpf_attr {
  *	Return
  *		Task group tag, if CONFIG_CGROUP_SCHED enabled, 0 as default tag, or
  *		a negative error in case of failure.
+ *
+ * long bpf_sched_task_tag_of(struct task_struct *tsk)
+ *	Description
+ *		Return task tag of *tsk*.The bpf prog obtains the tags to detect
+ *		different workloads.
+ *	Return
+ *		Task tag, if used, 0 as default tag, or a negative error in case of failure.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\
@@ -3949,6 +3956,7 @@ union bpf_attr {
 	FN(sched_entity_to_cgrpid),		\
 	FN(sched_entity_belongs_to_cgrp),	\
 	FN(sched_tg_tag_of),	\
+	FN(sched_task_tag_of),	\
 	/* */
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper