They will be used in task_diag
Signed-off-by: Andrey Vagin <ava...@openvz.org>
---
fs/proc/base.c | 79 ++-----------------------------------------------
include/linux/proc_fs.h | 4 +++
kernel/pid.c | 76 +++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 82 insertions(+), 77 deletions(-)
diff --git a/fs/proc/base.c b/fs/proc/base.c
index af797d9..4b72053 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -3213,81 +3213,6 @@ out_no_task:
return ERR_PTR(result);
}
-/*
- * Find the first tid of a thread group to return to user space.
- *
- * Usually this is just the thread group leader, but if the users
- * buffer was too small or there was a seek into the middle of the
- * directory we have more work todo.
- *
- * In the case of a short read we start with find_task_by_pid.
- *
- * In the case of a seek we start with the leader and walk nr
- * threads past it.
- */
-static struct task_struct *
-first_tid(struct task_struct *task, int tid, loff_t f_pos,
- struct pid_namespace *ns)
-{
- struct task_struct *pos;
- unsigned long nr = f_pos;
-
- if (nr != f_pos) /* 32bit overflow? */
- return NULL;
-
- rcu_read_lock();
-
- /* Attempt to start with the tid of a thread */
- if (tid && nr) {
- pos = find_task_by_pid_ns(tid, ns);
- if (pos && same_thread_group(pos, task))
- goto found;
- }
-
- /* If nr exceeds the number of threads there is nothing todo */
- if (nr >= get_nr_threads(task))
- goto fail;
-
- /* If we haven't found our starting place yet start
- * with the leader and walk nr threads forward.
- */
- pos = task = task->group_leader;
- do {
- if (!nr--)
- goto found;
- } while_each_thread(task, pos);
-fail:
- pos = NULL;
- goto out;
-found:
- get_task_struct(pos);
-out:
- rcu_read_unlock();
- return pos;
-}
-
-/*
- * Find the next thread in the thread list.
- * Return NULL if there is an error or no next thread.
- *
- * The reference to the input task_struct is released.
- */
-static struct task_struct *next_tid(struct task_struct *start)
-{
- struct task_struct *pos = NULL;
- rcu_read_lock();
- if (pid_alive(start)) {
- pos = next_thread(start);
- if (thread_group_leader(pos))
- pos = NULL;
- else
- get_task_struct(pos);
- }
- rcu_read_unlock();
- put_task_struct(start);
- return pos;
-}
-
/* for the /proc/TGID/task/ directories */
static int proc_task_readdir(struct file *file, struct dir_context *ctx)
{
@@ -3312,9 +3237,9 @@ static int proc_task_readdir(struct file *file, struct
dir_context *ctx)
ns = inode->i_sb->s_fs_info;
tid = (int)file->f_version;
file->f_version = 0;
- for (task = first_tid(start, tid, ctx->pos - 2, ns);
+ for (task = task_first_tid(start, tid, ctx->pos - 2, ns);
task;
- task = next_tid(task), ctx->pos++) {
+ task = task_next_tid(task), ctx->pos++) {
char name[PROC_NUMBUF];
int len;
tid = task_pid_nr_ns(task, ns);
diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h
index 62d0079..178f526 100644
--- a/include/linux/proc_fs.h
+++ b/include/linux/proc_fs.h
@@ -92,6 +92,10 @@ struct tgid_iter next_tgid(struct pid_namespace *ns, struct
tgid_iter iter);
struct task_struct *
task_next_child(struct task_struct *parent, struct task_struct *prev, unsigned
int pos);
+struct task_struct *task_first_tid(struct task_struct *task, int tid, loff_t
f_pos,
+ struct pid_namespace *ns);
+struct task_struct *task_next_tid(struct task_struct *start);
+
struct mem_size_stats {
unsigned long resident;
unsigned long shared_clean;
diff --git a/kernel/pid.c b/kernel/pid.c
index 42a6b40..b66f370 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -661,6 +661,82 @@ out:
}
/*
+ * Find the first tid of a thread group to return to user space.
+ *
+ * Usually this is just the thread group leader, but if the users
+ * buffer was too small or there was a seek into the middle of the
+ * directory we have more work todo.
+ *
+ * In the case of a short read we start with find_task_by_pid.
+ *
+ * In the case of a seek we start with the leader and walk nr
+ * threads past it.
+ */
+struct task_struct *
+task_first_tid(struct task_struct *task, int tid, loff_t f_pos,
+ struct pid_namespace *ns)
+{
+ struct task_struct *pos;
+ unsigned long nr = f_pos;
+
+ if (nr != f_pos) /* 32bit overflow? */
+ return NULL;
+
+ rcu_read_lock();
+
+ /* Attempt to start with the tid of a thread */
+ if (tid && nr) {
+ pos = find_task_by_pid_ns(tid, ns);
+ if (pos && same_thread_group(pos, task))
+ goto found;
+ }
+
+ /* If nr exceeds the number of threads there is nothing todo */
+ if (nr >= get_nr_threads(task))
+ goto fail;
+
+ /* If we haven't found our starting place yet start
+ * with the leader and walk nr threads forward.
+ */
+ pos = task = task->group_leader;
+ do {
+ if (!nr--)
+ goto found;
+ } while_each_thread(task, pos);
+fail:
+ pos = NULL;
+ goto out;
+found:
+ get_task_struct(pos);
+out:
+ rcu_read_unlock();
+ return pos;
+}
+
+/*
+ * Find the next thread in the thread list.
+ * Return NULL if there is an error or no next thread.
+ *
+ * The reference to the input task_struct is released.
+ */
+struct task_struct *task_next_tid(struct task_struct *start)
+{
+ struct task_struct *pos = NULL;
+ rcu_read_lock();
+ if (pid_alive(start)) {
+ pos = next_thread(start);
+ if (thread_group_leader(pos))
+ pos = NULL;
+ else
+ get_task_struct(pos);
+ }
+ rcu_read_unlock();
+ put_task_struct(start);
+ return pos;
+}
+
+
+/*
* The pid hash table is scaled according to the amount of memory in the
* machine. From a minimum of 16 slots up to 4096 slots at one gigabyte or
* more.
--
2.1.0
--
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