From: Guan Jing guanjing6@huawei.com
hulk inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I8OIT1
--------------------------------
Add user interface of task tag, bridges the information gap between user-mode and kernel mode.
Add proc interface: /proc/${pid}/task/${pid}/tag
Signed-off-by: Chen Hui judy.chenhui@huawei.com Signed-off-by: Ren Zhijie renzhijie2@huawei.com Signed-off-by: Hui Tang tanghui20@huawei.com Signed-off-by: Guan Jing guanjing6@huawei.com --- fs/proc/base.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 61 insertions(+)
diff --git a/fs/proc/base.c b/fs/proc/base.c index e04b0126334f..6f88566a4d79 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -3672,6 +3672,64 @@ static const struct inode_operations proc_tid_comm_inode_operations = { .permission = proc_tid_comm_permission, };
+#ifdef CONFIG_BPF_SCHED +static ssize_t pid_tag_write(struct file *file, const char __user *buf, + size_t count, loff_t *offset) +{ + struct inode *inode = file_inode(file); + struct task_struct *tsk; + int err = 0; + long tag = 0; + + tsk = get_proc_task(inode); + if (!tsk) + return -ESRCH; + + if (unlikely(tsk->pid == 1)) { + err = -EPERM; + goto out; + } + + err = kstrtol_from_user(buf, count, 0, &tag); + if (err) + goto out; + + sched_settag(tsk, tag); + +out: + put_task_struct(tsk); + return err < 0 ? err : count; +} + +static int pid_tag_show(struct seq_file *m, void *v) +{ + struct inode *inode = m->private; + struct task_struct *tsk; + + tsk = get_proc_task(inode); + if (!tsk) + return -ESRCH; + + seq_printf(m, "%ld\n", tsk->tag); + put_task_struct(tsk); + + return 0; +} + +static int pid_tag_open(struct inode *inode, struct file *flip) +{ + return single_open(flip, pid_tag_show, inode); +} + +static const struct file_operations proc_pid_tag_operations = { + .open = pid_tag_open, + .read = seq_read, + .write = pid_tag_write, + .llseek = seq_lseek, + .release = single_release, +}; +#endif + /* * Tasks */ @@ -3781,6 +3839,9 @@ static const struct pid_entry tid_base_stuff[] = { #ifdef CONFIG_QOS_SCHED_DYNAMIC_AFFINITY REG("preferred_cpuset", 0644, proc_preferred_cpuset_operations), #endif +#ifdef CONFIG_BPF_SCHED + REG("tag", 0644, proc_pid_tag_operations), +#endif };
static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx)